From 762a5e638314efa0f7a070e8568bfaf35bc87315 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 14 Apr 2024 14:53:35 +0200 Subject: Adding upstream version 1.24.1. Signed-off-by: Daniel Baumann --- AUTHORS | 7 + COPYING | 338 +++++++++ ChangeLog | 350 +++++++++ INSTALL | 82 +++ Makefile.in | 135 ++++ NEWS | 20 + README | 135 ++++ arg_parser.cc | 197 +++++ arg_parser.h | 110 +++ configure | 231 ++++++ decoder.cc | 276 +++++++ decoder.h | 346 +++++++++ doc/lzip.1 | 137 ++++ doc/lzip.info | 1728 ++++++++++++++++++++++++++++++++++++++++++++ doc/lzip.texi | 1800 ++++++++++++++++++++++++++++++++++++++++++++++ encoder.cc | 594 +++++++++++++++ encoder.h | 290 ++++++++ encoder_base.cc | 192 +++++ encoder_base.h | 482 +++++++++++++ fast_encoder.cc | 184 +++++ fast_encoder.h | 61 ++ list.cc | 114 +++ lzip.h | 372 ++++++++++ lzip_index.cc | 218 ++++++ lzip_index.h | 93 +++ main.cc | 1109 ++++++++++++++++++++++++++++ testsuite/check.sh | 478 ++++++++++++ testsuite/fox.lz | Bin 0 -> 80 bytes testsuite/fox6.lz | Bin 0 -> 480 bytes testsuite/fox6_mark.lz | Bin 0 -> 480 bytes testsuite/fox_bcrc.lz | Bin 0 -> 80 bytes testsuite/fox_crc0.lz | Bin 0 -> 80 bytes testsuite/fox_das46.lz | Bin 0 -> 80 bytes testsuite/fox_de20.lz | Bin 0 -> 80 bytes testsuite/fox_mes81.lz | Bin 0 -> 80 bytes testsuite/fox_s11.lz | Bin 0 -> 80 bytes testsuite/fox_v2.lz | Bin 0 -> 80 bytes testsuite/test.txt | 676 +++++++++++++++++ testsuite/test.txt.lz | Bin 0 -> 7376 bytes testsuite/test_em.txt.lz | Bin 0 -> 14024 bytes 40 files changed, 10755 insertions(+) create mode 100644 AUTHORS create mode 100644 COPYING create mode 100644 ChangeLog create mode 100644 INSTALL create mode 100644 Makefile.in create mode 100644 NEWS create mode 100644 README create mode 100644 arg_parser.cc create mode 100644 arg_parser.h create mode 100755 configure create mode 100644 decoder.cc create mode 100644 decoder.h create mode 100644 doc/lzip.1 create mode 100644 doc/lzip.info create mode 100644 doc/lzip.texi create mode 100644 encoder.cc create mode 100644 encoder.h create mode 100644 encoder_base.cc create mode 100644 encoder_base.h create mode 100644 fast_encoder.cc create mode 100644 fast_encoder.h create mode 100644 list.cc create mode 100644 lzip.h create mode 100644 lzip_index.cc create mode 100644 lzip_index.h create mode 100644 main.cc create mode 100755 testsuite/check.sh create mode 100644 testsuite/fox.lz create mode 100644 testsuite/fox6.lz create mode 100644 testsuite/fox6_mark.lz create mode 100644 testsuite/fox_bcrc.lz create mode 100644 testsuite/fox_crc0.lz create mode 100644 testsuite/fox_das46.lz create mode 100644 testsuite/fox_de20.lz create mode 100644 testsuite/fox_mes81.lz create mode 100644 testsuite/fox_s11.lz create mode 100644 testsuite/fox_v2.lz create mode 100644 testsuite/test.txt create mode 100644 testsuite/test.txt.lz create mode 100644 testsuite/test_em.txt.lz diff --git a/AUTHORS b/AUTHORS new file mode 100644 index 0000000..e08809c --- /dev/null +++ b/AUTHORS @@ -0,0 +1,7 @@ +Lzip was written by Antonio Diaz Diaz. + +The ideas embodied in lzip are due to (at least) the following people: +Abraham Lempel and Jacob Ziv (for the LZ algorithm), Andrei Markov (for the +definition of Markov chains), G.N.N. Martin (for the definition of range +encoding), Igor Pavlov (for putting all the above together in LZMA), and +Julian Seward (for bzip2's CLI). diff --git a/COPYING b/COPYING new file mode 100644 index 0000000..4ad17ae --- /dev/null +++ b/COPYING @@ -0,0 +1,338 @@ + GNU GENERAL PUBLIC LICENSE + Version 2, June 1991 + + Copyright (C) 1989, 1991 Free Software Foundation, Inc., + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The licenses for most software are designed to take away your +freedom to share and change it. By contrast, the GNU General Public +License is intended to guarantee your freedom to share and change free +software--to make sure the software is free for all its users. This +General Public License applies to most of the Free Software +Foundation's software and to any other program whose authors commit to +using it. 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If this is what you want to do, use the GNU Lesser General +Public License instead of this License. diff --git a/ChangeLog b/ChangeLog new file mode 100644 index 0000000..6a6e1ab --- /dev/null +++ b/ChangeLog @@ -0,0 +1,350 @@ +2024-03-01 Antonio Diaz Diaz + + * Version 1.24.1 released. + * main.cc: Fix compilation failure on MinGW because of mkdir. + +2024-01-26 Antonio Diaz Diaz + + * Version 1.24 released. + * New options '--empty-error' and '--marking-error'. + * main.cc: Reformat file diagnostics as 'PROGRAM: FILE: MESSAGE'. + (show_option_error): New function showing argument and option name. + (main): Make -o preserve date/mode/owner if 1 input file. + (open_outstream): Create missing intermediate directories. + * lzip.h: Rename verify_* to check_*. + * configure, Makefile.in: New variable 'MAKEINFO'. + * testsuite: New test files fox6.lz, fox6_mark.lz. + +2022-01-24 Antonio Diaz Diaz + + * Version 1.23 released. + * Decompression time has been reduced by 5-12% depending on the file. + * main.cc (getnum): Show option name and valid range if error. + * Improve several descriptions in manual, '--help', and man page. + * lzip.texi: Change GNU Texinfo category to 'Compression'. + (Reported by Alfred M. Szmidt). + +2021-01-04 Antonio Diaz Diaz + + * Version 1.22 released. + * main.cc (main): Report an error if a file name is empty. + Make '-o' behave like '-c', but writing to file instead of stdout. + Make '-c' and '-o' check whether the output is a terminal only once. + Do not open output if input is a terminal. + * configure: Build, check, and install without 'make'. + * Replace 'decompressed', 'compressed' with 'out', 'in' in output. + * lzip_index.cc: Improve messages for corruption in last header. + * main.cc: Set a valid invocation_name even if argc == 0. + * Document extraction from tar.lz in manual, '--help', and man page. + * lzip.texi (Introduction): Mention plzip and tarlz as alternatives. + * lzip.texi: Several fixes and improvements. + * testsuite: Add 9 new test files. + +2019-01-03 Antonio Diaz Diaz + + * Version 1.21 released. + * Rename File_* to Lzip_*. + * lzip.h (Lzip_trailer): New function 'verify_consistency'. + * lzip_index.cc: Detect some kinds of corrupt trailers. + * main.cc (main): Check return value of close( infd ). + * main.cc: Compile on DOS with DJGPP. + * Fix a GCC warning about catching std::bad_alloc by value. + * lzip.texi: Improve description of '-0..-9', '-m', and '-s'. + * configure: Accept appending to CXXFLAGS; 'CXXFLAGS+=OPTIONS'. + * INSTALL: Document use of CXXFLAGS+='-D __USE_MINGW_ANSI_STDIO'. + +2018-02-11 Antonio Diaz Diaz + + * Version 1.20 released. + * New option '--loose-trailing'. + * Improve corrupt header detection to HD=3. + * main.cc: Show corrupt or truncated header in multimember file. + * main.cc (main): Option '-S, --volume-size' now keeps input files. + * encoder_base.*: Adjust dictionary size for each member. + * Replace 'bits/byte' with inverse compression ratio in output. + * Show progress of decompression at verbosity level 2 (-vv). + * Show progress of (de)compression only if stderr is a terminal. + * main.cc: Show final diagnostic when testing multiple files. + * main.cc: Do not add a second extension '.lz' to the arg of '-o'. + * decoder.cc (verify_trailer): Show stored sizes also in hex. + Show dictionary size at verbosity level 4 (-vvvv). + * lzip.texi: New chapter 'Meaning of lzip's output'. + +2017-04-13 Antonio Diaz Diaz + + * Version 1.19 released. + * The option '-l, --list' has been ported from lziprecover. + * Don't allow mixing different operations (-d, -l or -t). + * Compression time of option '-0' has been slightly reduced. + * Decompression time has been reduced by 2%. + * main.cc: Continue testing if any input file is a terminal. + * main.cc: Show trailing data in both hexadecimal and ASCII. + * encoder.cc (Matchfinder_base): Check the size passed to new. + * lzip_index.cc: Improve detection of bad dict and trailing data. + * lzip.h: Unify messages for bad magic, trailing data, etc. + +2016-05-14 Antonio Diaz Diaz + + * Version 1.18 released. + * New option '-a, --trailing-error'. + * Decompression time has been reduced by 2%. + * decoder.cc (verify_trailer): Remove test of final code. + * main.cc (main): Delete '--output' file if infd is a terminal. + * main.cc (main): Don't use stdin more than once. + * Remove decompression support for version 0 files. + * lzip.texi: New chapter 'Trailing data'. + * configure: Avoid warning on some shells when testing for g++. + * Makefile.in: Detect the existence of install-info. + * check.sh: A POSIX shell is required to run the tests. + * check.sh: Don't check error messages. + +2015-07-12 Antonio Diaz Diaz + + * Version 1.17 released. + * Reorganization of the compression code. + * lzip.texi: New chapter 'Quality assurance'. + * Makefile.in: New targets 'install*-compress'. + +2014-08-26 Antonio Diaz Diaz + + * Version 1.16 released. + * Compression ratio of option '-9' has been slightly increased. + * Compression time has been reduced by 4%. + * Compression time of option '-0' has been reduced by 2%. + * main.cc (close_and_set_permissions): Behave like 'cp -p'. + * Minor improvements. + * lzip.texinfo: Rename to lzip.texi. + * Change license to GPL version 2 or later. + +2013-09-20 Antonio Diaz Diaz + + * Version 1.15 released. + * Show progress of compression at verbosity level 2 (-vv). + * main.cc (show_header): Don't show header version. + * Ignore option '-n, --threads' for compatibility with plzip. + * configure: Options now accept a separate argument. + * lzip.texinfo: New chapter 'Stream format' and appendix + 'Reference source code'. + +2013-02-17 Antonio Diaz Diaz + + * Version 1.14 released. + * Multi-step trials have been implemented. + * Compression ratio has been slightly increased. + * Compression time has been reduced by 5%. + * Decompression time has been reduced by 12%. + * Makefile.in: New target 'install-bin'. + * main.cc: Use 'setmode' instead of '_setmode' on Windows and OS/2. + * main.cc: Define 'strtoull' to 'std::strtoul' on Windows. + +2012-02-24 Antonio Diaz Diaz + + * Version 1.13 released. + * Lziprecover has been moved to its own package. + * main.cc (close_and_set_permissions): Inability to change output + file attributes has been downgraded from error to warning. + * Compression time of option '-0' has been reduced by 2%. + * Reorganization of the compression code. + * Small change in '--help' output and man page. + * Change quote characters in messages as advised by GNU Standards. + * configure: Rename 'datadir' to 'datarootdir'. + * 'unzcrash.cc' has been moved to package 'lziprecover'. + +2011-04-30 Antonio Diaz Diaz + + * Version 1.12 released. + * New option '-F, --recompress'. + * encoder.h (update_prices): Update high length symbol prices + independently of the value of 'pos_state'. This gives better + compression for large values of '--match-length' without being + slower. + * encoder.h, encoder.cc: Optimize pair price calculations, reducing + compression time for large values of '--match-length' by up to 6%. + * Compression time of option '-0' has been reduced by 2%. + * main.cc (decompress): Print only one status line for each + multimember file when only one '-v' is specified. + * main.cc (decompress): Print up to 6 bytes of trailing data when + '-vvvv' is specified. + * main.cc (open_instream): Don't show the message + " and '--stdout' was not specified" for directories, etc. + * lziprecover.cc: If '-v' is not specified show errors only. + * unzcrash.cc: Use Arg_parser. + * unzcrash.cc: New options '-b, --bits', '-p, --position', and + '-s, --size'. + +2010-09-16 Antonio Diaz Diaz + + * Version 1.11 released. + * New option '-0', which produces a compression speed and ratio + comparable to those of 'gzip -9'. + * fast_encoder.h, fast_encoder.cc: New files. + * main.cc: Match length limit set by options -1 to -8 has been + reduced to extend range of use towards gzip. Lower numbers now + compress less but faster. (-1 now takes 43% less time for only 20% + larger compressed size). + Exit with status 1 if any output file exists and is skipped. + * Compression ratio of option '-9' has been slightly increased. + * lziprecover.cc: New option '-m, --merge', which tries to produce a + correct file by merging the good parts of two or more damaged copies. + * lziprecover.cc: New option '-R, --repair' for repairing a + 1-byte error in single-member files. + * decoder.cc (decode_member): Detect file errors earlier to improve + efficiency of lziprecover's new repair capability. + This change also prevents (harmless) access to uninitialized + memory when decompressing a corrupt file. + * lziprecover.cc: New options '-f, --force' and '-o, --output'. + * lziprecover.cc: New option '-s, --split' to select the until now + only operation of splitting multimember files. + * lziprecover.cc: If no operation is specified, warn the user and do + nothing. + * main.cc: Fix warning about fchown's return value being ignored. + * decoder.cc: '-tvvvv' now also shows compression ratio. + * main.cc: Set stdin/stdout in binary mode on MSVC and OS2. + * lzip.texinfo: New examples. + * testsuite: Rename 'test1' to 'test.txt'. New tests. + * Matchfinder types HC4 (4 bytes hash-chain) and HT4 (4 bytes + hash-table) have been tested and found no better than the current + BT4. + +2010-04-05 Antonio Diaz Diaz + + * Version 1.10 released. + * decoder.h: Input_buffer integrated in Range_decoder. + * main.cc: File specified with option '-o' is now created with mode + 0666 if umask allows it, deleted if interrupted by user. + * main.cc: New constant 'o_binary'. + * main.cc: Dictionary size for options -2, -3, -4 and -8 has been + changed to improve linearity of compressed sizes. + * lzip.h: Fix warnings produced by over-optimization (-O3). + * Makefile.in: Add quotes to directory names. + +2010-01-17 Antonio Diaz Diaz + + * Version 1.9 released. + * main.cc (main): Return at least 1 if closing stdout fails. + * Makefile.in: Add option '--name' to help2man invocation. + * check.sh: Use 'test1' instead of 'COPYING' for testing. + +2009-09-02 Antonio Diaz Diaz + + * Version 1.8 released. + * Compression time has been reduced by 4%. + * Lzdiff and lzgrep have been moved to the new package zutils. + * Fix warnings on systems where uint32_t != unsigned int. + +2009-06-25 Antonio Diaz Diaz + + * Version 1.7 released. + * decoder.h (copy_block): Fix memcpy overlap introduced in 1.6. + +2009-06-22 Antonio Diaz Diaz + + * Version 1.6 released. + * Decompression time has been reduced by 17%. + * Add decompression support for Sync Flush marker. + * Add support for the extension '.tbz' to lzdiff and lzgrep. + * Add man pages for lzdiff, lzgrep and lziprecover. + * encoder.cc (Matchfinder): Reduce memory use to 9x if input file is + smaller than dictionary size limit. + * decoder.cc: Add extra flush calls to improve partial decompression + of corrupt files. + * '--test' no longer needs '/dev/null'. + * Remove some 'bashisms' from lzdiff and lzgrep. + * Dictionary size for options '-1' to '-4' has been changed. + * main.cc (signal_handler): Declare as 'extern "C"'. + * Makefile.in: Extra files are now installed by default. + * check.sh: Test lziprecover. + * Add 'export LC_ALL=C' to all scripts. + +2009-04-12 Antonio Diaz Diaz + + * Version 1.5 released. + * lzip.h: Implement coded dictionary size in Lzip_header. + * Fix some includes that prevented compilation with GCC 4.4. + * 'member_size' and 'volume_size' are now accurate limits. + * Compression speed has been improved. + * Implement bt4 type matchfinder. + * lzip.texinfo: New chapter 'Algorithm'. + * Lzdiff and lzgrep now accept '-h' for '--help' and + '-V' for '--version'. + * Makefile.in: Man page is now installed by default. + * check.sh: Check that files are opened in binary mode. + +2009-01-24 Antonio Diaz Diaz + + * Version 1.4 released. + * Implement compression of version 1 files. + * New options '-b, --member-size', '-S, --volume-size', and + '-o, --output'. + * main.cc: Read from non-regular files if '--stdout' is specified. + * Add 'lziprecover', a member recoverer program. + * unzcrash.cc: Test all 1-byte errors. + +2008-12-21 Antonio Diaz Diaz + + * Version 1.3 released. + * This version automatically chooses the smallest possible + dictionary size for each file during compression, saving memory + during decompression. + * Implement decompression of version 1 files. + * check.sh: Replace 'diff -q' with 'cmp'. + +2008-12-10 Antonio Diaz Diaz + + * Version 1.2 released. + * encoder.cc: A 1-byte read outside allocated memory has been fixed. + * lzip.h: Dictionary size limit has been reduced to 512 MiB because + setting it to 1 GiB causes overflow of a 32 bit integer. + * Add 'lzdiff', a diff/cmp wrapper for gzip, bzip2, lzip and + non-compressed files. + * Add 'lzgrep', a grep wrapper for gzip, bzip2, lzip and + non-compressed files. + * 'make install-info' should now work on Debian and OS X. + +2008-11-17 Antonio Diaz Diaz + + * Version 1.1 released. + * Change short name of option '--dictionary-size' to '-s'. + * Change short name of option '--match-length' to '-m'. + * Change LONG_LONG_MAX to LLONG_MAX. + +2008-10-14 Antonio Diaz Diaz + + * Version 1.0 released. + * '-tvv' shows file version and dictionary size. + +2008-09-30 Antonio Diaz Diaz + + * Version 0.5 released. + * Decompression is now 1% faster. + +2008-09-23 Antonio Diaz Diaz + + * Version 0.4 released. + * Code cleanup for global variable 'verbosity'. + * Regain the compression ratio of 0.2 with 5% faster speed. + * lzip.h: Fix compilation on systems where size_t != unsigned int. + +2008-09-15 Antonio Diaz Diaz + + * Version 0.3 released. + * encoder.cc: Compression is now 15% faster, 1% worse. + * main.cc (main): Make option '-t' override '-c'. + * main.cc (decompress): Show 'done' instead of 'ok' when not testing. + * encoder.h: Use trials[] to return the list of pairs. + +2008-09-09 Antonio Diaz Diaz + + * Version 0.2 released. + * encoder.cc: Small improvements in compression speed. + * Small documentation changes. + +2008-08-20 Antonio Diaz Diaz + + * Version 0.1 released. + + +Copyright (C) 2008-2024 Antonio Diaz Diaz. + +This file is a collection of facts, and thus it is not copyrightable, but just +in case, you have unlimited permission to copy, distribute, and modify it. diff --git a/INSTALL b/INSTALL new file mode 100644 index 0000000..a289e1c --- /dev/null +++ b/INSTALL @@ -0,0 +1,82 @@ +Requirements +------------ +You will need a C++98 compiler with support for 'long long'. +(gcc 3.3.6 or newer is recommended). +I use gcc 6.1.0 and 3.3.6, but the code should compile with any standards +compliant compiler. +Gcc is available at http://gcc.gnu.org. + +The operating system must allow signal handlers read access to objects with +static storage duration so that the cleanup handler for Control-C can delete +the partial output file. + + +Procedure +--------- +1. Unpack the archive if you have not done so already: + + tar -xf lzip[version].tar.lz +or + lzip -cd lzip[version].tar.lz | tar -xf - + +This creates the directory ./lzip[version] containing the source code +extracted from the archive. + +2. Change to lzip directory and run configure. + (Try 'configure --help' for usage instructions). + + cd lzip[version] + ./configure + + If you are compiling on MinGW, use: + + ./configure CXXFLAGS+='-D __USE_MINGW_ANSI_STDIO' + +3. Run make. + + make + +4. Optionally, type 'make check' to run the tests that come with lzip. + +5. Type 'make install' to install the program and any data files and + documentation. You need root privileges to install into a prefix owned + by root. + + Or type 'make install-compress', which additionally compresses the + info manual and the man page after installation. + (Installing compressed docs may become the default in the future). + + You can install only the program, the info manual, or the man page by + typing 'make install-bin', 'make install-info', or 'make install-man' + respectively. + + +Another way +----------- +You can also compile lzip into a separate directory. +To do this, you must use a version of 'make' that supports the variable +'VPATH', such as GNU 'make'. 'cd' to the directory where you want the +object files and executables to go and run the 'configure' script. +'configure' automatically checks for the source code in '.', in '..', and +in the directory that 'configure' is in. + +'configure' recognizes the option '--srcdir=DIR' to control where to look +for the source code. Usually 'configure' can determine that directory +automatically. + +After running 'configure', you can run 'make' and 'make install' as +explained above. + + +Building without 'make' +----------------------- +If you need to build lzip on a system lacking a 'make' program, you can use +'configure' to build, check, and install the lzip executable like this: + + ./configure --build --check --installdir=/usr/local/bin + + +Copyright (C) 2008-2024 Antonio Diaz Diaz. + +This file is free documentation: you have unlimited permission to copy, +distribute, and modify it. diff --git a/Makefile.in b/Makefile.in new file mode 100644 index 0000000..2b7f23c --- /dev/null +++ b/Makefile.in @@ -0,0 +1,135 @@ + +DISTNAME = $(pkgname)-$(pkgversion) +INSTALL = install +INSTALL_PROGRAM = $(INSTALL) -m 755 +INSTALL_DATA = $(INSTALL) -m 644 +INSTALL_DIR = $(INSTALL) -d -m 755 +SHELL = /bin/sh +CAN_RUN_INSTALLINFO = $(SHELL) -c "install-info --version" > /dev/null 2>&1 + +objs = arg_parser.o lzip_index.o list.o encoder_base.o encoder.o \ + fast_encoder.o decoder.o main.o + + +.PHONY : all install install-bin install-info install-man \ + install-strip install-compress install-strip-compress \ + install-bin-strip install-info-compress install-man-compress \ + uninstall uninstall-bin uninstall-info uninstall-man \ + doc info man check dist clean distclean + +all : $(progname) + +$(progname) : $(objs) + $(CXX) $(CXXFLAGS) $(LDFLAGS) -o $@ $(objs) + +main.o : main.cc + $(CXX) $(CPPFLAGS) $(CXXFLAGS) -DPROGVERSION=\"$(pkgversion)\" -c -o $@ $< + +%.o : %.cc + $(CXX) $(CPPFLAGS) $(CXXFLAGS) -c -o $@ $< + +$(objs) : Makefile +arg_parser.o : arg_parser.h +decoder.o : lzip.h decoder.h +encoder_base.o : lzip.h encoder_base.h +encoder.o : lzip.h encoder_base.h encoder.h +fast_encoder.o : lzip.h encoder_base.h fast_encoder.h +list.o : lzip.h lzip_index.h +lzip_index.o : lzip.h lzip_index.h +main.o : arg_parser.h lzip.h decoder.h encoder_base.h encoder.h fast_encoder.h + +doc : info man + +info : $(VPATH)/doc/$(pkgname).info + +$(VPATH)/doc/$(pkgname).info : $(VPATH)/doc/$(pkgname).texi + cd $(VPATH)/doc && $(MAKEINFO) $(pkgname).texi + +man : $(VPATH)/doc/$(progname).1 + +$(VPATH)/doc/$(progname).1 : $(progname) + help2man -n 'reduces the size of files' -o $@ ./$(progname) + +Makefile : $(VPATH)/configure $(VPATH)/Makefile.in + ./config.status + +check : all + @$(VPATH)/testsuite/check.sh $(VPATH)/testsuite $(pkgversion) + +install : install-bin install-info install-man +install-strip : install-bin-strip install-info install-man +install-compress : install-bin install-info-compress install-man-compress +install-strip-compress : install-bin-strip install-info-compress install-man-compress + +install-bin : all + if [ ! -d "$(DESTDIR)$(bindir)" ] ; then $(INSTALL_DIR) "$(DESTDIR)$(bindir)" ; fi + $(INSTALL_PROGRAM) ./$(progname) "$(DESTDIR)$(bindir)/$(progname)" + +install-bin-strip : all + $(MAKE) INSTALL_PROGRAM='$(INSTALL_PROGRAM) -s' install-bin + +install-info : + if [ ! -d "$(DESTDIR)$(infodir)" ] ; then $(INSTALL_DIR) "$(DESTDIR)$(infodir)" ; fi + -rm -f "$(DESTDIR)$(infodir)/$(pkgname).info"* + $(INSTALL_DATA) $(VPATH)/doc/$(pkgname).info "$(DESTDIR)$(infodir)/$(pkgname).info" + -if $(CAN_RUN_INSTALLINFO) ; then \ + install-info --info-dir="$(DESTDIR)$(infodir)" "$(DESTDIR)$(infodir)/$(pkgname).info" ; \ + fi + +install-info-compress : install-info + lzip -v -9 "$(DESTDIR)$(infodir)/$(pkgname).info" + +install-man : + if [ ! -d "$(DESTDIR)$(mandir)/man1" ] ; then $(INSTALL_DIR) "$(DESTDIR)$(mandir)/man1" ; fi + -rm -f "$(DESTDIR)$(mandir)/man1/$(progname).1"* + $(INSTALL_DATA) $(VPATH)/doc/$(progname).1 "$(DESTDIR)$(mandir)/man1/$(progname).1" + +install-man-compress : install-man + lzip -v -9 "$(DESTDIR)$(mandir)/man1/$(progname).1" + +uninstall : uninstall-man uninstall-info uninstall-bin + +uninstall-bin : + -rm -f "$(DESTDIR)$(bindir)/$(progname)" + +uninstall-info : + -if $(CAN_RUN_INSTALLINFO) ; then \ + install-info --info-dir="$(DESTDIR)$(infodir)" --remove "$(DESTDIR)$(infodir)/$(pkgname).info" ; \ + fi + -rm -f "$(DESTDIR)$(infodir)/$(pkgname).info"* + +uninstall-man : + -rm -f "$(DESTDIR)$(mandir)/man1/$(progname).1"* + +dist : doc + ln -sf $(VPATH) $(DISTNAME) + tar -Hustar --owner=root --group=root -cvf $(DISTNAME).tar \ + $(DISTNAME)/AUTHORS \ + $(DISTNAME)/COPYING \ + $(DISTNAME)/ChangeLog \ + $(DISTNAME)/INSTALL \ + $(DISTNAME)/Makefile.in \ + $(DISTNAME)/NEWS \ + $(DISTNAME)/README \ + $(DISTNAME)/configure \ + $(DISTNAME)/doc/$(progname).1 \ + $(DISTNAME)/doc/$(pkgname).info \ + $(DISTNAME)/doc/$(pkgname).texi \ + $(DISTNAME)/*.h \ + $(DISTNAME)/*.cc \ + $(DISTNAME)/testsuite/check.sh \ + $(DISTNAME)/testsuite/test.txt \ + $(DISTNAME)/testsuite/fox.lz \ + $(DISTNAME)/testsuite/fox_*.lz \ + $(DISTNAME)/testsuite/fox6.lz \ + $(DISTNAME)/testsuite/fox6_mark.lz \ + $(DISTNAME)/testsuite/test.txt.lz \ + $(DISTNAME)/testsuite/test_em.txt.lz + rm -f $(DISTNAME) + lzip -v -9 $(DISTNAME).tar + +clean : + -rm -f $(progname) $(objs) + +distclean : clean + -rm -f Makefile config.status *.tar *.tar.lz diff --git a/NEWS b/NEWS new file mode 100644 index 0000000..9a97821 --- /dev/null +++ b/NEWS @@ -0,0 +1,20 @@ +Changes in version 1.24: + +The option '--empty-error', which forces exit status 2 if any empty member +is found, has been added. + +The option '--marking-error', which forces exit status 2 if the first LZMA +byte is non-zero in any member, has been added. + +File diagnostics have been reformatted as 'PROGRAM: FILE: MESSAGE'. + +Diagnostics caused by invalid arguments to command-line options now show the +argument and the name of the option. + +The option '-o, --output' now preserves dates, permissions, and ownership of +the file when (de)compressing exactly one file. + +The option '-o, --output' now creates missing intermediate directories when +writing to a file. + +The variable MAKEINFO has been added to configure and Makefile.in. diff --git a/README b/README new file mode 100644 index 0000000..a4806ce --- /dev/null +++ b/README @@ -0,0 +1,135 @@ +Description + +Lzip is a lossless data compressor with a user interface similar to the one +of gzip or bzip2. Lzip uses a simplified form of the 'Lempel-Ziv-Markov +chain-Algorithm' (LZMA) stream format to maximize interoperability. The +maximum dictionary size is 512 MiB so that any lzip file can be decompressed +on 32-bit machines. Lzip provides accurate and robust 3-factor integrity +checking. Lzip can compress about as fast as gzip (lzip -0) or compress most +files more than bzip2 (lzip -9). Decompression speed is intermediate between +gzip and bzip2. Lzip is better than gzip and bzip2 from a data recovery +perspective. Lzip has been designed, written, and tested with great care to +replace gzip and bzip2 as the standard general-purpose compressed format for +Unix-like systems. + +For compressing/decompressing large files on multiprocessor machines plzip +can be much faster than lzip at the cost of a slightly reduced compression +ratio. + +For creation and manipulation of compressed tar archives tarlz can be more +efficient than using tar and plzip because tarlz is able to keep the +alignment between tar members and lzip members. + +The lzip file format is designed for data sharing and long-term archiving, +taking into account both data integrity and decoder availability: + + * The lzip format provides very safe integrity checking and some data + recovery means. The program lziprecover can repair bit flip errors + (one of the most common forms of data corruption) in lzip files, and + provides data recovery capabilities, including error-checked merging + of damaged copies of a file. + + * The lzip format is as simple as possible (but not simpler). The lzip + manual provides the source code of a simple decompressor along with a + detailed explanation of how it works, so that with the only help of the + lzip manual it would be possible for a digital archaeologist to extract + the data from a lzip file long after quantum computers eventually + render LZMA obsolete. + + * Additionally the lzip reference implementation is copylefted, which + guarantees that it will remain free forever. + +A nice feature of the lzip format is that a corrupt byte is easier to repair +the nearer it is from the beginning of the file. Therefore, with the help of +lziprecover, losing an entire archive just because of a corrupt byte near +the beginning is a thing of the past. + +Lzip uses the same well-defined exit status values used by bzip2, which +makes it safer than compressors returning ambiguous warning values (like +gzip) when it is used as a back end for other programs like tar or zutils. + +Lzip automatically uses for each file the largest dictionary size that does +not exceed neither the file size nor the limit given. Keep in mind that the +decompression memory requirement is affected at compression time by the +choice of dictionary size limit. + +The amount of memory required for compression is about 1 or 2 times the +dictionary size limit (1 if input file size is less than dictionary size +limit, else 2) plus 9 times the dictionary size really used. The option '-0' +is special and only requires about 1.5 MiB at most. The amount of memory +required for decompression is about 46 kB larger than the dictionary size +really used. + +When compressing, lzip replaces every file given in the command line +with a compressed version of itself, with the name "original_name.lz". +When decompressing, lzip attempts to guess the name for the decompressed +file from that of the compressed file as follows: + +filename.lz becomes filename +filename.tlz becomes filename.tar +anyothername becomes anyothername.out + +(De)compressing a file is much like copying or moving it. Therefore lzip +preserves the access and modification dates, permissions, and, if you have +appropriate privileges, ownership of the file just as 'cp -p' does. (If the +user ID or the group ID can't be duplicated, the file permission bits +S_ISUID and S_ISGID are cleared). + +Lzip is able to read from some types of non-regular files if either the +option '-c' or the option '-o' is specified. + +If no file names are specified, lzip compresses (or decompresses) from +standard input to standard output. Lzip refuses to read compressed data +from a terminal or write compressed data to a terminal, as this would be +entirely incomprehensible and might leave the terminal in an abnormal state. + +Lzip correctly decompresses a file which is the concatenation of two or +more compressed files. The result is the concatenation of the corresponding +decompressed files. Integrity testing of concatenated compressed files is +also supported. + +Lzip can produce multimember files, and lziprecover can safely recover the +undamaged members in case of file damage. Lzip can also split the compressed +output in volumes of a given size, even when reading from standard input. +This allows the direct creation of multivolume compressed tar archives. + +Lzip is able to compress and decompress streams of unlimited size by +automatically creating multimember output. The members so created are large, +about 2 PiB each. + +In spite of its name (Lempel-Ziv-Markov chain-Algorithm), LZMA is not a +concrete algorithm; it is more like "any algorithm using the LZMA coding +scheme". For example, the option '-0' of lzip uses the scheme in almost the +simplest way possible; issuing the longest match it can find, or a literal +byte if it can't find a match. Inversely, a much more elaborated way of +finding coding sequences of minimum size than the one currently used by lzip +could be developed, and the resulting sequence could also be coded using the +LZMA coding scheme. + +Lzip currently implements two variants of the LZMA algorithm: fast +(used by option '-0') and normal (used by all other compression levels). + +The high compression of LZMA comes from combining two basic, well-proven +compression ideas: sliding dictionaries (LZ77) and Markov models (the thing +used by every compression algorithm that uses a range encoder or similar +order-0 entropy coder as its last stage) with segregation of contexts +according to what the bits are used for. + +The ideas embodied in lzip are due to (at least) the following people: +Abraham Lempel and Jacob Ziv (for the LZ algorithm), Andrei Markov (for the +definition of Markov chains), G.N.N. Martin (for the definition of range +encoding), Igor Pavlov (for putting all the above together in LZMA), and +Julian Seward (for bzip2's CLI). + +LANGUAGE NOTE: Uncompressed = not compressed = plain data; it may never have +been compressed. Decompressed is used to refer to data which have undergone +the process of decompression. + + +Copyright (C) 2008-2024 Antonio Diaz Diaz. + +This file is free documentation: you have unlimited permission to copy, +distribute, and modify it. + +The file Makefile.in is a data file used by configure to produce the Makefile. +It has the same copyright owner and permissions that configure itself. diff --git a/arg_parser.cc b/arg_parser.cc new file mode 100644 index 0000000..0c04d8e --- /dev/null +++ b/arg_parser.cc @@ -0,0 +1,197 @@ +/* Arg_parser - POSIX/GNU command-line argument parser. (C++ version) + Copyright (C) 2006-2024 Antonio Diaz Diaz. + + This library is free software. Redistribution and use in source and + binary forms, with or without modification, are permitted provided + that the following conditions are met: + + 1. Redistributions of source code must retain the above copyright + notice, this list of conditions, and the following disclaimer. + + 2. Redistributions in binary form must reproduce the above copyright + notice, this list of conditions, and the following disclaimer in the + documentation and/or other materials provided with the distribution. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. +*/ + +#include +#include +#include + +#include "arg_parser.h" + + +bool Arg_parser::parse_long_option( const char * const opt, const char * const arg, + const Option options[], int & argind ) + { + unsigned len; + int index = -1; + bool exact = false, ambig = false; + + for( len = 0; opt[len+2] && opt[len+2] != '='; ++len ) ; + + // Test all long options for either exact match or abbreviated matches. + for( int i = 0; options[i].code != 0; ++i ) + if( options[i].long_name && + std::strncmp( options[i].long_name, &opt[2], len ) == 0 ) + { + if( std::strlen( options[i].long_name ) == len ) // Exact match found + { index = i; exact = true; break; } + else if( index < 0 ) index = i; // First nonexact match found + else if( options[index].code != options[i].code || + options[index].has_arg != options[i].has_arg ) + ambig = true; // Second or later nonexact match found + } + + if( ambig && !exact ) + { + error_ = "option '"; error_ += opt; error_ += "' is ambiguous"; + return false; + } + + if( index < 0 ) // nothing found + { + error_ = "unrecognized option '"; error_ += opt; error_ += '\''; + return false; + } + + ++argind; + data.push_back( Record( options[index].code, options[index].long_name ) ); + + if( opt[len+2] ) // '--=' syntax + { + if( options[index].has_arg == no ) + { + error_ = "option '--"; error_ += options[index].long_name; + error_ += "' doesn't allow an argument"; + return false; + } + if( options[index].has_arg == yes && !opt[len+3] ) + { + error_ = "option '--"; error_ += options[index].long_name; + error_ += "' requires an argument"; + return false; + } + data.back().argument = &opt[len+3]; + return true; + } + + if( options[index].has_arg == yes ) + { + if( !arg || !arg[0] ) + { + error_ = "option '--"; error_ += options[index].long_name; + error_ += "' requires an argument"; + return false; + } + ++argind; data.back().argument = arg; + return true; + } + + return true; + } + + +bool Arg_parser::parse_short_option( const char * const opt, const char * const arg, + const Option options[], int & argind ) + { + int cind = 1; // character index in opt + + while( cind > 0 ) + { + int index = -1; + const unsigned char c = opt[cind]; + + if( c != 0 ) + for( int i = 0; options[i].code; ++i ) + if( c == options[i].code ) + { index = i; break; } + + if( index < 0 ) + { + error_ = "invalid option -- '"; error_ += c; error_ += '\''; + return false; + } + + data.push_back( Record( c ) ); + if( opt[++cind] == 0 ) { ++argind; cind = 0; } // opt finished + + if( options[index].has_arg != no && cind > 0 && opt[cind] ) + { + data.back().argument = &opt[cind]; ++argind; cind = 0; + } + else if( options[index].has_arg == yes ) + { + if( !arg || !arg[0] ) + { + error_ = "option requires an argument -- '"; error_ += c; + error_ += '\''; + return false; + } + data.back().argument = arg; ++argind; cind = 0; + } + } + return true; + } + + +Arg_parser::Arg_parser( const int argc, const char * const argv[], + const Option options[], const bool in_order ) + { + if( argc < 2 || !argv || !options ) return; + + std::vector< const char * > non_options; // skipped non-options + int argind = 1; // index in argv + + while( argind < argc ) + { + const unsigned char ch1 = argv[argind][0]; + const unsigned char ch2 = ch1 ? argv[argind][1] : 0; + + if( ch1 == '-' && ch2 ) // we found an option + { + const char * const opt = argv[argind]; + const char * const arg = ( argind + 1 < argc ) ? argv[argind+1] : 0; + if( ch2 == '-' ) + { + if( !argv[argind][2] ) { ++argind; break; } // we found "--" + else if( !parse_long_option( opt, arg, options, argind ) ) break; + } + else if( !parse_short_option( opt, arg, options, argind ) ) break; + } + else + { + if( in_order ) data.push_back( Record( argv[argind++] ) ); + else non_options.push_back( argv[argind++] ); + } + } + if( !error_.empty() ) data.clear(); + else + { + for( unsigned i = 0; i < non_options.size(); ++i ) + data.push_back( Record( non_options[i] ) ); + while( argind < argc ) + data.push_back( Record( argv[argind++] ) ); + } + } + + +Arg_parser::Arg_parser( const char * const opt, const char * const arg, + const Option options[] ) + { + if( !opt || !opt[0] || !options ) return; + + if( opt[0] == '-' && opt[1] ) // we found an option + { + int argind = 1; // dummy + if( opt[1] == '-' ) + { if( opt[2] ) parse_long_option( opt, arg, options, argind ); } + else + parse_short_option( opt, arg, options, argind ); + if( !error_.empty() ) data.clear(); + } + else data.push_back( Record( opt ) ); + } diff --git a/arg_parser.h b/arg_parser.h new file mode 100644 index 0000000..1eeec9a --- /dev/null +++ b/arg_parser.h @@ -0,0 +1,110 @@ +/* Arg_parser - POSIX/GNU command-line argument parser. (C++ version) + Copyright (C) 2006-2024 Antonio Diaz Diaz. + + This library is free software. Redistribution and use in source and + binary forms, with or without modification, are permitted provided + that the following conditions are met: + + 1. Redistributions of source code must retain the above copyright + notice, this list of conditions, and the following disclaimer. + + 2. Redistributions in binary form must reproduce the above copyright + notice, this list of conditions, and the following disclaimer in the + documentation and/or other materials provided with the distribution. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. +*/ + +/* Arg_parser reads the arguments in 'argv' and creates a number of + option codes, option arguments, and non-option arguments. + + In case of error, 'error' returns a non-empty error message. + + 'options' is an array of 'struct Option' terminated by an element + containing a code which is zero. A null long_name means a short-only + option. A code value outside the unsigned char range means a long-only + option. + + Arg_parser normally makes it appear as if all the option arguments + were specified before all the non-option arguments for the purposes + of parsing, even if the user of your program intermixed option and + non-option arguments. If you want the arguments in the exact order + the user typed them, call 'Arg_parser' with 'in_order' = true. + + The argument '--' terminates all options; any following arguments are + treated as non-option arguments, even if they begin with a hyphen. + + The syntax for optional option arguments is '-' + (without whitespace), or '--='. +*/ + +class Arg_parser + { +public: + enum Has_arg { no, yes, maybe }; + + struct Option + { + int code; // Short option letter or code ( code != 0 ) + const char * long_name; // Long option name (maybe null) + Has_arg has_arg; + }; + +private: + struct Record + { + int code; + std::string parsed_name; + std::string argument; + explicit Record( const unsigned char c ) + : code( c ), parsed_name( "-" ) { parsed_name += c; } + Record( const int c, const char * const long_name ) + : code( c ), parsed_name( "--" ) { parsed_name += long_name; } + explicit Record( const char * const arg ) : code( 0 ), argument( arg ) {} + }; + + const std::string empty_arg; + std::string error_; + std::vector< Record > data; + + bool parse_long_option( const char * const opt, const char * const arg, + const Option options[], int & argind ); + bool parse_short_option( const char * const opt, const char * const arg, + const Option options[], int & argind ); + +public: + Arg_parser( const int argc, const char * const argv[], + const Option options[], const bool in_order = false ); + + // Restricted constructor. Parses a single token and argument (if any). + Arg_parser( const char * const opt, const char * const arg, + const Option options[] ); + + const std::string & error() const { return error_; } + + // The number of arguments parsed. May be different from argc. + int arguments() const { return data.size(); } + + /* If code( i ) is 0, argument( i ) is a non-option. + Else argument( i ) is the option's argument (or empty). */ + int code( const int i ) const + { + if( i >= 0 && i < arguments() ) return data[i].code; + else return 0; + } + + // Full name of the option parsed (short or long). + const std::string & parsed_name( const int i ) const + { + if( i >= 0 && i < arguments() ) return data[i].parsed_name; + else return empty_arg; + } + + const std::string & argument( const int i ) const + { + if( i >= 0 && i < arguments() ) return data[i].argument; + else return empty_arg; + } + }; diff --git a/configure b/configure new file mode 100755 index 0000000..e75835e --- /dev/null +++ b/configure @@ -0,0 +1,231 @@ +#! /bin/sh +# configure script for Lzip - LZMA lossless data compressor +# Copyright (C) 2008-2024 Antonio Diaz Diaz. +# +# This configure script is free software: you have unlimited permission +# to copy, distribute, and modify it. + +pkgname=lzip +pkgversion=1.24.1 +progname=lzip +srctrigger=doc/${pkgname}.texi + +# clear some things potentially inherited from environment. +LC_ALL=C +export LC_ALL +srcdir= +prefix=/usr/local +exec_prefix='$(prefix)' +bindir='$(exec_prefix)/bin' +datarootdir='$(prefix)/share' +infodir='$(datarootdir)/info' +mandir='$(datarootdir)/man' +build=no +check=no +installdir= +CXX=g++ +CPPFLAGS= +CXXFLAGS='-Wall -W -O2' +LDFLAGS= +MAKEINFO=makeinfo + +# checking whether we are using GNU C++. +/bin/sh -c "${CXX} --version" > /dev/null 2>&1 || { CXX=c++ ; CXXFLAGS=-O2 ; } + +# Loop over all args +args= +no_create= +while [ $# != 0 ] ; do + + # Get the first arg, and shuffle + option=$1 ; arg2=no + shift + + # Add the argument quoted to args + if [ -z "${args}" ] ; then args="\"${option}\"" + else args="${args} \"${option}\"" ; fi + + # Split out the argument for options that take them + case ${option} in + *=*) optarg=`echo "${option}" | sed -e 's,^[^=]*=,,;s,/$,,'` ;; + esac + + # Process the options + case ${option} in + --help | -h) + echo "Usage: $0 [OPTION]... [VAR=VALUE]..." + echo + echo "To assign makefile variables (e.g., CXX, CXXFLAGS...), specify them as" + echo "arguments to configure in the form VAR=VALUE." + echo + echo "Options and variables: [defaults in brackets]" + echo " -h, --help display this help and exit" + echo " -V, --version output version information and exit" + echo " --srcdir=DIR find the source code in DIR [. or ..]" + echo " --prefix=DIR install into DIR [${prefix}]" + echo " --exec-prefix=DIR base directory for arch-dependent files [${exec_prefix}]" + echo " --bindir=DIR user executables directory [${bindir}]" + echo " --datarootdir=DIR base directory for doc and data [${datarootdir}]" + echo " --infodir=DIR info files directory [${infodir}]" + echo " --mandir=DIR man pages directory [${mandir}]" + echo " --build build in one step without using 'make'" + echo " --check check without using 'make', implies --build" + echo " --installdir=BINDIR install without using 'make', implies --build" + echo " CXX=COMPILER C++ compiler to use [${CXX}]" + echo " CPPFLAGS=OPTIONS command-line options for the preprocessor [${CPPFLAGS}]" + echo " CXXFLAGS=OPTIONS command-line options for the C++ compiler [${CXXFLAGS}]" + echo " CXXFLAGS+=OPTIONS append options to the current value of CXXFLAGS" + echo " LDFLAGS=OPTIONS command-line options for the linker [${LDFLAGS}]" + echo " MAKEINFO=NAME makeinfo program to use [${MAKEINFO}]" + echo + exit 0 ;; + --version | -V) + echo "Configure script for ${pkgname} version ${pkgversion}" + exit 0 ;; + --srcdir) srcdir=$1 ; arg2=yes ;; + --prefix) prefix=$1 ; arg2=yes ;; + --exec-prefix) exec_prefix=$1 ; arg2=yes ;; + --bindir) bindir=$1 ; arg2=yes ;; + --datarootdir) datarootdir=$1 ; arg2=yes ;; + --infodir) infodir=$1 ; arg2=yes ;; + --mandir) mandir=$1 ; arg2=yes ;; + --installdir) installdir=$1 ; arg2=yes ;; + + --srcdir=*) srcdir=${optarg} ;; + --prefix=*) prefix=${optarg} ;; + --exec-prefix=*) exec_prefix=${optarg} ;; + --bindir=*) bindir=${optarg} ;; + --datarootdir=*) datarootdir=${optarg} ;; + --infodir=*) infodir=${optarg} ;; + --mandir=*) mandir=${optarg} ;; + --build) build=yes ;; + --check) check=yes ; build=yes ;; + --installdir=*) installdir=${optarg} ; build=yes ;; + --no-create) no_create=yes ;; + + CXX=*) CXX=${optarg} ;; + CPPFLAGS=*) CPPFLAGS=${optarg} ;; + CXXFLAGS=*) CXXFLAGS=${optarg} ;; + CXXFLAGS+=*) CXXFLAGS="${CXXFLAGS} ${optarg}" ;; + LDFLAGS=*) LDFLAGS=${optarg} ;; + MAKEINFO=*) MAKEINFO=${optarg} ;; + + --*) + echo "configure: WARNING: unrecognized option: '${option}'" 1>&2 ;; + *=* | *-*-*) ;; + *) + echo "configure: unrecognized option: '${option}'" 1>&2 + echo "Try 'configure --help' for more information." 1>&2 + exit 1 ;; + esac + + # Check if the option took a separate argument + if [ "${arg2}" = yes ] ; then + if [ $# != 0 ] ; then args="${args} \"$1\"" ; shift + else echo "configure: Missing argument to '${option}'" 1>&2 + exit 1 + fi + fi +done + +# Find the source code, if location was not specified. +srcdirtext= +if [ -z "${srcdir}" ] ; then + srcdirtext="or . or .." ; srcdir=. + if [ ! -r "${srcdir}/${srctrigger}" ] ; then srcdir=.. ; fi + if [ ! -r "${srcdir}/${srctrigger}" ] ; then + ## the sed command below emulates the dirname command + srcdir=`echo "$0" | sed -e 's,[^/]*$,,;s,/$,,;s,^$,.,'` + fi +fi + +if [ ! -r "${srcdir}/${srctrigger}" ] ; then + echo "configure: Can't find source code in ${srcdir} ${srcdirtext}" 1>&2 + echo "configure: (At least ${srctrigger} is missing)." 1>&2 + exit 1 +fi + +# Set srcdir to . if that's what it is. +if [ "`pwd`" = "`cd "${srcdir}" ; pwd`" ] ; then srcdir=. ; fi + +if [ "${build}" = yes ] ; then + objs=$(sed -e :a -e '/\\$/N; s/\\\n//; ta' "${srcdir}/Makefile.in" | \ + sed -n -e 's/^ *objs *= *//p' | sed -e 's/ \{2,\}/ /g') + for ofile in ${objs} ; do + file="${ofile%.o}.cc" ; pver= + [ "${ofile}" = main.o ] && pver=" -DPROGVERSION=\"${pkgversion}\"" + compile_command="${CXX} ${CPPFLAGS} ${CXXFLAGS}${pver} -c -o ${ofile}" + echo "${compile_command} ${srcdir}/${file}" + ${compile_command} "${srcdir}/${file}" || exit 1 + done + link_command="${CXX} ${LDFLAGS} ${CXXFLAGS} -o ${progname} ${objs}" + echo "${link_command}" ; ${link_command} || exit 1 + if [ "${check}" = yes ] ; then + "${srcdir}/testsuite/check.sh" "${srcdir}/testsuite" ${pkgversion} || exit 1 + fi + if [ -n "${installdir}" ] ; then + echo "installing ${progname} in ${installdir}" + [ -d "${installdir}" ] || mkdir -p "${installdir}" || exit 1 + cp -fp ${progname} "${installdir}/${progname}" || exit 1 + fi + exit 0 +fi + +echo +if [ -z "${no_create}" ] ; then + echo "creating config.status" + rm -f config.status + cat > config.status << EOF +#! /bin/sh +# This file was generated automatically by configure. Don't edit. +# Run this file to recreate the current configuration. +# +# This script is free software: you have unlimited permission +# to copy, distribute, and modify it. + +exec /bin/sh "$0" ${args} --no-create +EOF + chmod +x config.status +fi + +echo "creating Makefile" +echo "VPATH = ${srcdir}" +echo "prefix = ${prefix}" +echo "exec_prefix = ${exec_prefix}" +echo "bindir = ${bindir}" +echo "datarootdir = ${datarootdir}" +echo "infodir = ${infodir}" +echo "mandir = ${mandir}" +echo "CXX = ${CXX}" +echo "CPPFLAGS = ${CPPFLAGS}" +echo "CXXFLAGS = ${CXXFLAGS}" +echo "LDFLAGS = ${LDFLAGS}" +echo "MAKEINFO = ${MAKEINFO}" +rm -f Makefile +cat > Makefile << EOF +# Makefile for Lzip - LZMA lossless data compressor +# Copyright (C) 2008-2024 Antonio Diaz Diaz. +# This file was generated automatically by configure. Don't edit. +# +# This Makefile is free software: you have unlimited permission +# to copy, distribute, and modify it. + +pkgname = ${pkgname} +pkgversion = ${pkgversion} +progname = ${progname} +VPATH = ${srcdir} +prefix = ${prefix} +exec_prefix = ${exec_prefix} +bindir = ${bindir} +datarootdir = ${datarootdir} +infodir = ${infodir} +mandir = ${mandir} +CXX = ${CXX} +CPPFLAGS = ${CPPFLAGS} +CXXFLAGS = ${CXXFLAGS} +LDFLAGS = ${LDFLAGS} +MAKEINFO = ${MAKEINFO} +EOF +cat "${srcdir}/Makefile.in" >> Makefile + +echo "OK. Now you can run make." diff --git a/decoder.cc b/decoder.cc new file mode 100644 index 0000000..16aa016 --- /dev/null +++ b/decoder.cc @@ -0,0 +1,276 @@ +/* Lzip - LZMA lossless data compressor + Copyright (C) 2008-2024 Antonio Diaz Diaz. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . +*/ + +#define _FILE_OFFSET_BITS 64 + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "lzip.h" +#include "decoder.h" + + +/* Return the number of bytes really read. + If (value returned < size) and (errno == 0), means EOF was reached. +*/ +int readblock( const int fd, uint8_t * const buf, const int size ) + { + int sz = 0; + errno = 0; + while( sz < size ) + { + const int n = read( fd, buf + sz, size - sz ); + if( n > 0 ) sz += n; + else if( n == 0 ) break; // EOF + else if( errno != EINTR ) break; + errno = 0; + } + return sz; + } + + +/* Return the number of bytes really written. + If (value returned < size), it is always an error. +*/ +int writeblock( const int fd, const uint8_t * const buf, const int size ) + { + int sz = 0; + errno = 0; + while( sz < size ) + { + const int n = write( fd, buf + sz, size - sz ); + if( n > 0 ) sz += n; + else if( n < 0 && errno != EINTR ) break; + errno = 0; + } + return sz; + } + + +bool Range_decoder::read_block() + { + if( !at_stream_end ) + { + stream_pos = readblock( infd, buffer, buffer_size ); + if( stream_pos != buffer_size && errno ) throw Error( "Read error" ); + at_stream_end = ( stream_pos < buffer_size ); + partial_member_pos += pos; + pos = 0; + show_dprogress(); + } + return pos < stream_pos; + } + + +void LZ_decoder::flush_data() + { + if( pos > stream_pos ) + { + const int size = pos - stream_pos; + crc32.update_buf( crc_, buffer + stream_pos, size ); + if( outfd >= 0 && writeblock( outfd, buffer + stream_pos, size ) != size ) + throw Error( "Write error" ); + if( pos >= dictionary_size ) + { partial_data_pos += pos; pos = 0; pos_wrapped = true; } + stream_pos = pos; + } + } + + +int LZ_decoder::check_trailer( const Pretty_print & pp, + const bool ignore_empty ) const + { + Lzip_trailer trailer; + int size = rdec.read_data( trailer.data, trailer.size ); + bool error = false; + + if( size < trailer.size ) + { + error = true; + if( verbosity >= 0 ) + { pp(); + std::fprintf( stderr, "Trailer truncated at trailer position %d;" + " some checks may fail.\n", size ); } + while( size < trailer.size ) trailer.data[size++] = 0; + } + + const unsigned td_crc = trailer.data_crc(); + if( td_crc != crc() ) + { + error = true; + if( verbosity >= 0 ) + { pp(); + std::fprintf( stderr, "CRC mismatch; stored %08X, computed %08X\n", + td_crc, crc() ); } + } + const unsigned long long data_size = data_position(); + const unsigned long long td_size = trailer.data_size(); + if( td_size != data_size ) + { + error = true; + if( verbosity >= 0 ) + { pp(); + std::fprintf( stderr, "Data size mismatch; stored %llu (0x%llX), computed %llu (0x%llX)\n", + td_size, td_size, data_size, data_size ); } + } + const unsigned long long member_size = rdec.member_position(); + const unsigned long long tm_size = trailer.member_size(); + if( tm_size != member_size ) + { + error = true; + if( verbosity >= 0 ) + { pp(); + std::fprintf( stderr, "Member size mismatch; stored %llu (0x%llX), computed %llu (0x%llX)\n", + tm_size, tm_size, member_size, member_size ); } + } + if( error ) return 3; + if( !ignore_empty && data_size == 0 ) return 5; + if( verbosity >= 2 ) + { + if( verbosity >= 4 ) show_header( dictionary_size ); + if( data_size == 0 || member_size == 0 ) + std::fputs( "no data compressed. ", stderr ); + else + std::fprintf( stderr, "%6.3f:1, %5.2f%% ratio, %5.2f%% saved. ", + (double)data_size / member_size, + ( 100.0 * member_size ) / data_size, + 100.0 - ( ( 100.0 * member_size ) / data_size ) ); + if( verbosity >= 4 ) std::fprintf( stderr, "CRC %08X, ", td_crc ); + if( verbosity >= 3 ) + std::fprintf( stderr, "%9llu out, %8llu in. ", data_size, member_size ); + } + return 0; + } + + +/* Return value: 0 = OK, 1 = decoder error, 2 = unexpected EOF, + 3 = trailer error, 4 = unknown marker found, + 5 = empty member found, 6 = marked member found. */ +int LZ_decoder::decode_member( const Cl_options & cl_opts, + const Pretty_print & pp ) + { + Bit_model bm_literal[1<= start_dis_model ) + { + const unsigned dis_slot = distance; + const int direct_bits = ( dis_slot >> 1 ) - 1; + distance = ( 2 | ( dis_slot & 1 ) ) << direct_bits; + if( dis_slot < end_dis_model ) + distance += rdec.decode_tree_reversed( + bm_dis + ( distance - dis_slot ), direct_bits ); + else + { + distance += + rdec.decode( direct_bits - dis_align_bits ) << dis_align_bits; + distance += rdec.decode_tree_reversed4( bm_align ); + if( distance == 0xFFFFFFFFU ) // marker found + { + rdec.normalize(); + flush_data(); + if( len == min_match_len ) // End Of Stream marker + return check_trailer( pp, cl_opts.ignore_empty ); + if( len == min_match_len + 1 ) // Sync Flush marker + { rdec.load(); continue; } + if( verbosity >= 0 ) + { + pp(); + std::fprintf( stderr, "Unsupported marker code '%d'\n", len ); + } + return 4; + } + } + } + rep3 = rep2; rep2 = rep1; rep1 = rep0; rep0 = distance; + state.set_match(); + if( rep0 >= dictionary_size || ( rep0 >= pos && !pos_wrapped ) ) + { flush_data(); return 1; } + } + copy_block( rep0, len ); + } + flush_data(); + return 2; + } diff --git a/decoder.h b/decoder.h new file mode 100644 index 0000000..cf10f3d --- /dev/null +++ b/decoder.h @@ -0,0 +1,346 @@ +/* Lzip - LZMA lossless data compressor + Copyright (C) 2008-2024 Antonio Diaz Diaz. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . +*/ + +class Range_decoder + { + enum { buffer_size = 16384 }; + unsigned long long partial_member_pos; + uint8_t * const buffer; // input buffer + int pos; // current pos in buffer + int stream_pos; // when reached, a new block must be read + uint32_t code; + uint32_t range; + const int infd; // input file descriptor + bool at_stream_end; + + bool read_block(); + + Range_decoder( const Range_decoder & ); // declared as private + void operator=( const Range_decoder & ); // declared as private + +public: + explicit Range_decoder( const int ifd ) + : + partial_member_pos( 0 ), + buffer( new uint8_t[buffer_size] ), + pos( 0 ), + stream_pos( 0 ), + code( 0 ), + range( 0xFFFFFFFFU ), + infd( ifd ), + at_stream_end( false ) + {} + + ~Range_decoder() { delete[] buffer; } + + bool finished() { return pos >= stream_pos && !read_block(); } + + unsigned long long member_position() const + { return partial_member_pos + pos; } + + void reset_member_position() + { partial_member_pos = 0; partial_member_pos -= pos; } + + uint8_t get_byte() + { + // 0xFF avoids decoder error if member is truncated at EOS marker + if( finished() ) return 0xFF; + return buffer[pos++]; + } + + int read_data( uint8_t * const outbuf, const int size ) + { + int sz = 0; + while( sz < size && !finished() ) + { + const int rd = std::min( size - sz, stream_pos - pos ); + std::memcpy( outbuf + sz, buffer + pos, rd ); + pos += rd; + sz += rd; + } + return sz; + } + + bool load( const bool ignore_marking = true ) + { + code = 0; + range = 0xFFFFFFFFU; + // check and discard first byte of the LZMA stream + if( get_byte() != 0 && !ignore_marking ) return false; + for( int i = 0; i < 4; ++i ) code = ( code << 8 ) | get_byte(); + return true; + } + + void normalize() + { + if( range <= 0x00FFFFFFU ) + { range <<= 8; code = ( code << 8 ) | get_byte(); } + } + + unsigned decode( const int num_bits ) + { + unsigned symbol = 0; + for( int i = num_bits; i > 0; --i ) + { + normalize(); + range >>= 1; +// symbol <<= 1; +// if( code >= range ) { code -= range; symbol |= 1; } + const bool bit = ( code >= range ); + symbol <<= 1; symbol += bit; + code -= range & ( 0U - bit ); + } + return symbol; + } + + bool decode_bit( Bit_model & bm ) + { + normalize(); + const uint32_t bound = ( range >> bit_model_total_bits ) * bm.probability; + if( code < bound ) + { + range = bound; + bm.probability += + ( bit_model_total - bm.probability ) >> bit_model_move_bits; + return 0; + } + else + { + code -= bound; + range -= bound; + bm.probability -= bm.probability >> bit_model_move_bits; + return 1; + } + } + + void decode_symbol_bit( Bit_model & bm, unsigned & symbol ) + { + normalize(); + symbol <<= 1; + const uint32_t bound = ( range >> bit_model_total_bits ) * bm.probability; + if( code < bound ) + { + range = bound; + bm.probability += + ( bit_model_total - bm.probability ) >> bit_model_move_bits; + } + else + { + code -= bound; + range -= bound; + bm.probability -= bm.probability >> bit_model_move_bits; + symbol |= 1; + } + } + + void decode_symbol_bit_reversed( Bit_model & bm, unsigned & model, + unsigned & symbol, const int i ) + { + normalize(); + model <<= 1; + const uint32_t bound = ( range >> bit_model_total_bits ) * bm.probability; + if( code < bound ) + { + range = bound; + bm.probability += + ( bit_model_total - bm.probability ) >> bit_model_move_bits; + } + else + { + code -= bound; + range -= bound; + bm.probability -= bm.probability >> bit_model_move_bits; + model |= 1; + symbol |= 1 << i; + } + } + + unsigned decode_tree6( Bit_model bm[] ) + { + unsigned symbol = 1; + decode_symbol_bit( bm[symbol], symbol ); + decode_symbol_bit( bm[symbol], symbol ); + decode_symbol_bit( bm[symbol], symbol ); + decode_symbol_bit( bm[symbol], symbol ); + decode_symbol_bit( bm[symbol], symbol ); + decode_symbol_bit( bm[symbol], symbol ); + return symbol & 0x3F; + } + + unsigned decode_tree8( Bit_model bm[] ) + { + unsigned symbol = 1; + decode_symbol_bit( bm[symbol], symbol ); + decode_symbol_bit( bm[symbol], symbol ); + decode_symbol_bit( bm[symbol], symbol ); + decode_symbol_bit( bm[symbol], symbol ); + decode_symbol_bit( bm[symbol], symbol ); + decode_symbol_bit( bm[symbol], symbol ); + decode_symbol_bit( bm[symbol], symbol ); + decode_symbol_bit( bm[symbol], symbol ); + return symbol & 0xFF; + } + + unsigned decode_tree_reversed( Bit_model bm[], const int num_bits ) + { + unsigned model = 1; + unsigned symbol = 0; + for( int i = 0; i < num_bits; ++i ) + decode_symbol_bit_reversed( bm[model], model, symbol, i ); + return symbol; + } + + unsigned decode_tree_reversed4( Bit_model bm[] ) + { + unsigned model = 1; + unsigned symbol = 0; + decode_symbol_bit_reversed( bm[model], model, symbol, 0 ); + decode_symbol_bit_reversed( bm[model], model, symbol, 1 ); + decode_symbol_bit_reversed( bm[model], model, symbol, 2 ); + decode_symbol_bit_reversed( bm[model], model, symbol, 3 ); + return symbol; + } + + unsigned decode_matched( Bit_model bm[], unsigned match_byte ) + { + Bit_model * const bm1 = bm + 0x100; + unsigned symbol = 1; + while( symbol < 0x100 ) + { + const unsigned match_bit = ( match_byte <<= 1 ) & 0x100; + const bool bit = decode_bit( bm1[symbol+match_bit] ); + symbol <<= 1; symbol |= bit; + if( match_bit >> 8 != bit ) + { + while( symbol < 0x100 ) decode_symbol_bit( bm[symbol], symbol ); + break; + } + } + return symbol & 0xFF; + } + + unsigned decode_len( Len_model & lm, const int pos_state ) + { + Bit_model * bm; + unsigned mask, offset, symbol = 1; + + if( decode_bit( lm.choice1 ) == 0 ) + { bm = lm.bm_low[pos_state]; mask = 7; offset = 0; goto len3; } + if( decode_bit( lm.choice2 ) == 0 ) + { bm = lm.bm_mid[pos_state]; mask = 7; offset = len_low_symbols; goto len3; } + bm = lm.bm_high; mask = 0xFF; offset = len_low_symbols + len_mid_symbols; + decode_symbol_bit( bm[symbol], symbol ); + decode_symbol_bit( bm[symbol], symbol ); + decode_symbol_bit( bm[symbol], symbol ); + decode_symbol_bit( bm[symbol], symbol ); + decode_symbol_bit( bm[symbol], symbol ); +len3: + decode_symbol_bit( bm[symbol], symbol ); + decode_symbol_bit( bm[symbol], symbol ); + decode_symbol_bit( bm[symbol], symbol ); + return ( symbol & mask ) + min_match_len + offset; + } + }; + + +class LZ_decoder + { + unsigned long long partial_data_pos; + Range_decoder & rdec; + const unsigned dictionary_size; + uint8_t * const buffer; // output buffer + unsigned pos; // current pos in buffer + unsigned stream_pos; // first byte not yet written to file + uint32_t crc_; + const int outfd; // output file descriptor + bool pos_wrapped; + + void flush_data(); + int check_trailer( const Pretty_print & pp, const bool ignore_empty ) const; + + uint8_t peek_prev() const + { return buffer[((pos > 0) ? pos : dictionary_size)-1]; } + + uint8_t peek( const unsigned distance ) const + { + const unsigned i = ( ( pos > distance ) ? 0 : dictionary_size ) + + pos - distance - 1; + return buffer[i]; + } + + void put_byte( const uint8_t b ) + { + buffer[pos] = b; + if( ++pos >= dictionary_size ) flush_data(); + } + + void copy_block( const unsigned distance, unsigned len ) + { + unsigned lpos = pos, i = lpos - distance - 1; + bool fast, fast2; + if( lpos > distance ) + { + fast = ( len < dictionary_size - lpos ); + fast2 = ( fast && len <= lpos - i ); + } + else + { + i += dictionary_size; + fast = ( len < dictionary_size - i ); // (i == pos) may happen + fast2 = ( fast && len <= i - lpos ); + } + if( fast ) // no wrap + { + pos += len; + if( fast2 ) // no wrap, no overlap + std::memcpy( buffer + lpos, buffer + i, len ); + else + for( ; len > 0; --len ) buffer[lpos++] = buffer[i++]; + } + else for( ; len > 0; --len ) + { + buffer[pos] = buffer[i]; + if( ++pos >= dictionary_size ) flush_data(); + if( ++i >= dictionary_size ) i = 0; + } + } + + LZ_decoder( const LZ_decoder & ); // declared as private + void operator=( const LZ_decoder & ); // declared as private + +public: + LZ_decoder( Range_decoder & rde, const unsigned dict_size, const int ofd ) + : + partial_data_pos( 0 ), + rdec( rde ), + dictionary_size( dict_size ), + buffer( new uint8_t[dictionary_size] ), + pos( 0 ), + stream_pos( 0 ), + crc_( 0xFFFFFFFFU ), + outfd( ofd ), + pos_wrapped( false ) + // prev_byte of first byte; also for peek( 0 ) on corrupt file + { buffer[dictionary_size-1] = 0; } + + ~LZ_decoder() { delete[] buffer; } + + unsigned crc() const { return crc_ ^ 0xFFFFFFFFU; } + unsigned long long data_position() const { return partial_data_pos + pos; } + + int decode_member( const Cl_options & cl_opts, const Pretty_print & pp ); + }; diff --git a/doc/lzip.1 b/doc/lzip.1 new file mode 100644 index 0000000..9d711e8 --- /dev/null +++ b/doc/lzip.1 @@ -0,0 +1,137 @@ +.\" DO NOT MODIFY THIS FILE! It was generated by help2man 1.49.2. +.TH LZIP "1" "March 2024" "lzip 1.24.1" "User Commands" +.SH NAME +lzip \- reduces the size of files +.SH SYNOPSIS +.B lzip +[\fI\,options\/\fR] [\fI\,files\/\fR] +.SH DESCRIPTION +Lzip is a lossless data compressor with a user interface similar to the one +of gzip or bzip2. Lzip uses a simplified form of the 'Lempel\-Ziv\-Markov +chain\-Algorithm' (LZMA) stream format to maximize interoperability. The +maximum dictionary size is 512 MiB so that any lzip file can be decompressed +on 32\-bit machines. Lzip provides accurate and robust 3\-factor integrity +checking. Lzip can compress about as fast as gzip (lzip \fB\-0\fR) or compress most +files more than bzip2 (lzip \fB\-9\fR). Decompression speed is intermediate between +gzip and bzip2. Lzip is better than gzip and bzip2 from a data recovery +perspective. Lzip has been designed, written, and tested with great care to +replace gzip and bzip2 as the standard general\-purpose compressed format for +Unix\-like systems. +.SH OPTIONS +.TP +\fB\-h\fR, \fB\-\-help\fR +display this help and exit +.TP +\fB\-V\fR, \fB\-\-version\fR +output version information and exit +.TP +\fB\-a\fR, \fB\-\-trailing\-error\fR +exit with error status if trailing data +.TP +\fB\-b\fR, \fB\-\-member\-size=\fR +set member size limit in bytes +.TP +\fB\-c\fR, \fB\-\-stdout\fR +write to standard output, keep input files +.TP +\fB\-d\fR, \fB\-\-decompress\fR +decompress, test compressed file integrity +.TP +\fB\-f\fR, \fB\-\-force\fR +overwrite existing output files +.TP +\fB\-F\fR, \fB\-\-recompress\fR +force re\-compression of compressed files +.TP +\fB\-k\fR, \fB\-\-keep\fR +keep (don't delete) input files +.TP +\fB\-l\fR, \fB\-\-list\fR +print (un)compressed file sizes +.TP +\fB\-m\fR, \fB\-\-match\-length=\fR +set match length limit in bytes [36] +.TP +\fB\-o\fR, \fB\-\-output=\fR +write to , keep input files +.TP +\fB\-q\fR, \fB\-\-quiet\fR +suppress all messages +.TP +\fB\-s\fR, \fB\-\-dictionary\-size=\fR +set dictionary size limit in bytes [8 MiB] +.TP +\fB\-S\fR, \fB\-\-volume\-size=\fR +set volume size limit in bytes +.TP +\fB\-t\fR, \fB\-\-test\fR +test compressed file integrity +.TP +\fB\-v\fR, \fB\-\-verbose\fR +be verbose (a 2nd \fB\-v\fR gives more) +.TP +\fB\-0\fR .. \fB\-9\fR +set compression level [default 6] +.TP +\fB\-\-fast\fR +alias for \fB\-0\fR +.TP +\fB\-\-best\fR +alias for \fB\-9\fR +.TP +\fB\-\-empty\-error\fR +exit with error status if empty member in file +.TP +\fB\-\-marking\-error\fR +exit with error status if 1st LZMA byte not 0 +.TP +\fB\-\-loose\-trailing\fR +allow trailing data seeming corrupt header +.PP +If no file names are given, or if a file is '\-', lzip compresses or +decompresses from standard input to standard output. +Numbers may be followed by a multiplier: k = kB = 10^3 = 1000, +Ki = KiB = 2^10 = 1024, M = 10^6, Mi = 2^20, G = 10^9, Gi = 2^30, etc... +Dictionary sizes 12 to 29 are interpreted as powers of two, meaning 2^12 to +2^29 bytes. +.PP +The bidimensional parameter space of LZMA can't be mapped to a linear scale +optimal for all files. If your files are large, very repetitive, etc, you +may need to use the options \fB\-\-dictionary\-size\fR and \fB\-\-match\-length\fR directly +to achieve optimal performance. +.PP +To extract all the files from archive 'foo.tar.lz', use the commands +\&'tar \fB\-xf\fR foo.tar.lz' or 'lzip \fB\-cd\fR foo.tar.lz | tar \fB\-xf\fR \-'. +.PP +Exit status: 0 for a normal exit, 1 for environmental problems +(file not found, invalid command\-line options, I/O errors, etc), 2 to +indicate a corrupt or invalid input file, 3 for an internal consistency +error (e.g., bug) which caused lzip to panic. +.PP +The ideas embodied in lzip are due to (at least) the following people: +Abraham Lempel and Jacob Ziv (for the LZ algorithm), Andrei Markov (for the +definition of Markov chains), G.N.N. Martin (for the definition of range +encoding), Igor Pavlov (for putting all the above together in LZMA), and +Julian Seward (for bzip2's CLI). +.SH "REPORTING BUGS" +Report bugs to lzip\-bug@nongnu.org +.br +Lzip home page: http://www.nongnu.org/lzip/lzip.html +.SH COPYRIGHT +Copyright \(co 2024 Antonio Diaz Diaz. +License GPLv2+: GNU GPL version 2 or later +.br +This is free software: you are free to change and redistribute it. +There is NO WARRANTY, to the extent permitted by law. +.SH "SEE ALSO" +The full documentation for +.B lzip +is maintained as a Texinfo manual. If the +.B info +and +.B lzip +programs are properly installed at your site, the command +.IP +.B info lzip +.PP +should give you access to the complete manual. diff --git a/doc/lzip.info b/doc/lzip.info new file mode 100644 index 0000000..04f81c4 --- /dev/null +++ b/doc/lzip.info @@ -0,0 +1,1728 @@ +This is lzip.info, produced by makeinfo version 4.13+ from lzip.texi. + +INFO-DIR-SECTION Compression +START-INFO-DIR-ENTRY +* Lzip: (lzip). LZMA lossless data compressor +END-INFO-DIR-ENTRY + + +File: lzip.info, Node: Top, Next: Introduction, Up: (dir) + +Lzip Manual +*********** + +This manual is for Lzip (version 1.24.1, 1 March 2024). + +* Menu: + +* Introduction:: Purpose and features of lzip +* Output:: Meaning of lzip's output +* Invoking lzip:: Command-line interface +* Quality assurance:: Design, development, and testing of lzip +* Algorithm:: How lzip compresses the data +* File format:: Detailed format of the compressed file +* Stream format:: Format of the LZMA stream in lzip files +* Trailing data:: Extra data appended to the file +* Examples:: A small tutorial with examples +* Problems:: Reporting bugs +* Reference source code:: Source code illustrating stream format +* Concept index:: Index of concepts + + + Copyright (C) 2008-2024 Antonio Diaz Diaz. + + This manual is free documentation: you have unlimited permission to copy, +distribute, and modify it. + + +File: lzip.info, Node: Introduction, Next: Output, Prev: Top, Up: Top + +1 Introduction +************** + +Lzip is a lossless data compressor with a user interface similar to the one +of gzip or bzip2. Lzip uses a simplified form of the 'Lempel-Ziv-Markov +chain-Algorithm' (LZMA) stream format to maximize interoperability. The +maximum dictionary size is 512 MiB so that any lzip file can be decompressed +on 32-bit machines. Lzip provides accurate and robust 3-factor integrity +checking. Lzip can compress about as fast as gzip (lzip -0) or compress most +files more than bzip2 (lzip -9). Decompression speed is intermediate between +gzip and bzip2. Lzip is better than gzip and bzip2 from a data recovery +perspective. Lzip has been designed, written, and tested with great care to +replace gzip and bzip2 as the standard general-purpose compressed format for +Unix-like systems. + + For compressing/decompressing large files on multiprocessor machines +plzip can be much faster than lzip at the cost of a slightly reduced +compression ratio. *Note plzip manual: (plzip)Top. + + For creation and manipulation of compressed tar archives tarlz can be +more efficient than using tar and plzip because tarlz is able to keep the +alignment between tar members and lzip members. *Note tarlz manual: +(tarlz)Top. + + The lzip file format is designed for data sharing and long-term +archiving, taking into account both data integrity and decoder availability: + + * The lzip format provides very safe integrity checking and some data + recovery means. The program lziprecover can repair bit flip errors + (one of the most common forms of data corruption) in lzip files, and + provides data recovery capabilities, including error-checked merging + of damaged copies of a file. *Note Data safety: (lziprecover)Data + safety. + + * The lzip format is as simple as possible (but not simpler). The lzip + manual provides the source code of a simple decompressor along with a + detailed explanation of how it works, so that with the only help of the + lzip manual it would be possible for a digital archaeologist to extract + the data from a lzip file long after quantum computers eventually + render LZMA obsolete. + + * Additionally the lzip reference implementation is copylefted, which + guarantees that it will remain free forever. + + A nice feature of the lzip format is that a corrupt byte is easier to +repair the nearer it is from the beginning of the file. Therefore, with the +help of lziprecover, losing an entire archive just because of a corrupt +byte near the beginning is a thing of the past. + + The member trailer stores the 32-bit CRC of the original data, the size +of the original data, and the size of the member. These values, together +with the "End Of Stream" marker, provide a 3-factor integrity checking which +guarantees that the decompressed version of the data is identical to the +original. This guards against corruption of the compressed data, and against +undetected bugs in lzip (hopefully very unlikely). The chances of data +corruption going undetected are microscopic. Be aware, though, that the +check occurs upon decompression, so it can only tell you that something is +wrong. It can't help you recover the original uncompressed data. + + Lzip uses the same well-defined exit status values used by bzip2, which +makes it safer than compressors returning ambiguous warning values (like +gzip) when it is used as a back end for other programs like tar or zutils. + + Lzip automatically uses for each file the largest dictionary size that +does not exceed neither the file size nor the limit given. Keep in mind +that the decompression memory requirement is affected at compression time +by the choice of dictionary size limit. + + The amount of memory required for compression is about 1 or 2 times the +dictionary size limit (1 if input file size is less than dictionary size +limit, else 2) plus 9 times the dictionary size really used. The option +'-0' is special and only requires about 1.5 MiB at most. The amount of +memory required for decompression is about 46 kB larger than the dictionary +size really used. + + When compressing, lzip replaces every file given in the command line +with a compressed version of itself, with the name "original_name.lz". When +decompressing, lzip attempts to guess the name for the decompressed file +from that of the compressed file as follows: + +filename.lz becomes filename +filename.tlz becomes filename.tar +anyothername becomes anyothername.out + + (De)compressing a file is much like copying or moving it. Therefore lzip +preserves the access and modification dates, permissions, and, if you have +appropriate privileges, ownership of the file just as 'cp -p' does. (If the +user ID or the group ID can't be duplicated, the file permission bits +S_ISUID and S_ISGID are cleared). + + Lzip is able to read from some types of non-regular files if either the +option '-c' or the option '-o' is specified. + + Lzip refuses to read compressed data from a terminal or write compressed +data to a terminal, as this would be entirely incomprehensible and might +leave the terminal in an abnormal state. + + Lzip correctly decompresses a file which is the concatenation of two or +more compressed files. The result is the concatenation of the corresponding +decompressed files. Integrity testing of concatenated compressed files is +also supported. + + Lzip can produce multimember files, and lziprecover can safely recover +the undamaged members in case of file damage. Lzip can also split the +compressed output in volumes of a given size, even when reading from +standard input. This allows the direct creation of multivolume compressed +tar archives. + + Lzip is able to compress and decompress streams of unlimited size by +automatically creating multimember output. The members so created are large, +about 2 PiB each. + + +File: lzip.info, Node: Output, Next: Invoking lzip, Prev: Introduction, Up: Top + +2 Meaning of lzip's output +************************** + +The output of lzip looks like this: + + lzip -v foo + foo: 6.676:1, 14.98% ratio, 85.02% saved, 450560 in, 67493 out. + + lzip -tvvv foo.lz + foo.lz: 6.676:1, 14.98% ratio, 85.02% saved. 450560 out, 67493 in. ok + + The meaning of each field is as follows: + +'N:1' + The compression ratio (uncompressed_size / compressed_size), shown as + N to 1. + +'ratio' + The inverse compression ratio (compressed_size / uncompressed_size), + shown as a percentage. A decimal ratio is easily obtained by moving the + decimal point two places to the left; 14.98% = 0.1498. + +'saved' + The space saved by compression (1 - ratio), shown as a percentage. + +'in' + Size of the input data. This is the uncompressed size when + compressing, or the compressed size when decompressing or testing. + Note that lzip always prints the uncompressed size before the + compressed size when compressing, decompressing, testing, or listing. + +'out' + Size of the output data. This is the compressed size when compressing, + or the decompressed size when decompressing or testing. + + + When decompressing or testing at verbosity level 4 (-vvvv), the +dictionary size used to compress the file and the CRC32 of the uncompressed +data are also shown. + + LANGUAGE NOTE: Uncompressed = not compressed = plain data; it may never +have been compressed. Decompressed is used to refer to data which have +undergone the process of decompression. + + +File: lzip.info, Node: Invoking lzip, Next: Quality assurance, Prev: Output, Up: Top + +3 Invoking lzip +*************** + +The format for running lzip is: + + lzip [OPTIONS] [FILES] + +If no file names are specified, lzip compresses (or decompresses) from +standard input to standard output. A hyphen '-' used as a FILE argument +means standard input. It can be mixed with other FILES and is read just +once, the first time it appears in the command line. Remember to prepend +'./' to any file name beginning with a hyphen, or use '--'. + + lzip supports the following options: *Note Argument syntax: +(arg_parser)Argument syntax. + +'-h' +'--help' + Print an informative help message describing the options and exit. + +'-V' +'--version' + Print the version number of lzip on the standard output and exit. This + version number should be included in all bug reports. + +'-a' +'--trailing-error' + Exit with error status 2 if any remaining input is detected after + decompressing the last member. Such remaining input is usually trailing + garbage that can be safely ignored. *Note concat-example::. + +'-b BYTES' +'--member-size=BYTES' + When compressing, set the member size limit to BYTES. It is advisable + to keep members smaller than RAM size so that they can be repaired with + lziprecover in case of corruption. A small member size may degrade + compression ratio, so use it only when needed. Valid values range from + 100 kB to 2 PiB. Defaults to 2 PiB. + +'-c' +'--stdout' + Compress or decompress to standard output; keep input files unchanged. + If compressing several files, each file is compressed independently. + (The output consists of a sequence of independently compressed + members). This option (or '-o') is needed when reading from a named + pipe (fifo) or from a device. Use it also to recover as much of the + decompressed data as possible when decompressing a corrupt file. '-c' + overrides '-o' and '-S'. '-c' has no effect when testing or listing. + +'-d' +'--decompress' + Decompress the files specified. The integrity of the files specified is + checked. If a file does not exist, can't be opened, or the destination + file already exists and '--force' has not been specified, lzip + continues decompressing the rest of the files and exits with error + status 1. If a file fails to decompress, or is a terminal, lzip exits + immediately with error status 2 without decompressing the rest of the + files. A terminal is considered an uncompressed file, and therefore + invalid. + +'-f' +'--force' + Force overwrite of output files. + +'-F' +'--recompress' + When compressing, force re-compression of files whose name already has + the '.lz' or '.tlz' suffix. + +'-k' +'--keep' + Keep (don't delete) input files during compression or decompression. + +'-l' +'--list' + Print the uncompressed size, compressed size, and percentage saved of + the files specified. Trailing data are ignored. The values produced + are correct even for multimember files. If more than one file is + given, a final line containing the cumulative sizes is printed. With + '-v', the dictionary size, the number of members in the file, and the + amount of trailing data (if any) are also printed. With '-vv', the + positions and sizes of each member in multimember files are also + printed. + + If any file is damaged, does not exist, can't be opened, or is not + regular, the final exit status is > 0. '-lq' can be used to check + quickly (without decompressing) the structural integrity of the files + specified. (Use '--test' to check the data integrity). '-alq' + additionally checks that none of the files specified contain trailing + data. + +'-m BYTES' +'--match-length=BYTES' + When compressing, set the match length limit in bytes. After a match + this long is found, the search is finished. Valid values range from 5 + to 273. Larger values usually give better compression ratios but + longer compression times. + +'-o FILE' +'--output=FILE' + If '-c' has not been also specified, write the (de)compressed output + to FILE, automatically creating any missing parent directories; keep + input files unchanged. If compressing several files, each file is + compressed independently. (The output consists of a sequence of + independently compressed members). This option (or '-c') is needed + when reading from a named pipe (fifo) or from a device. '-o -' is + equivalent to '-c'. '-o' has no effect when testing or listing. + + In order to keep backward compatibility with lzip versions prior to + 1.22, when compressing from standard input and no other file names are + given, the extension '.lz' is appended to FILE unless it already ends + in '.lz' or '.tlz'. This feature will be removed in a future version + of lzip. Meanwhile, redirection may be used instead of '-o' to write + the compressed output to a file without the extension '.lz' in its + name: 'lzip < file > foo'. + + When compressing and splitting the output in volumes, FILE is used as + a prefix, and several files named 'FILE00001.lz', 'FILE00002.lz', etc, + are created. In this case, only one input file is allowed. + +'-q' +'--quiet' + Quiet operation. Suppress all messages. + +'-s BYTES' +'--dictionary-size=BYTES' + When compressing, set the dictionary size limit in bytes. Lzip uses for + each file the largest dictionary size that does not exceed neither the + file size nor this limit. Valid values range from 4 KiB to 512 MiB. + Values 12 to 29 are interpreted as powers of two, meaning 2^12 to 2^29 + bytes. Dictionary sizes are quantized so that they can be coded in + just one byte (*note coded-dict-size::). If the size specified does + not match one of the valid sizes, it is rounded upwards by adding up + to (BYTES / 8) to it. + + For maximum compression you should use a dictionary size limit as large + as possible, but keep in mind that the decompression memory requirement + is affected at compression time by the choice of dictionary size limit. + +'-S BYTES' +'--volume-size=BYTES' + When compressing, and '-c' has not been also specified, split the + compressed output into several volume files with names + 'original_name00001.lz', 'original_name00002.lz', etc, and set the + volume size limit to BYTES. Input files are kept unchanged. Each + volume is a complete, maybe multimember, lzip file. A small volume + size may degrade compression ratio, so use it only when needed. Valid + values range from 100 kB to 4 EiB. + +'-t' +'--test' + Check integrity of the files specified, but don't decompress them. This + really performs a trial decompression and throws away the result. Use + it together with '-v' to see information about the files. If a file + fails the test, does not exist, can't be opened, or is a terminal, lzip + continues testing the rest of the files. A final diagnostic is shown at + verbosity level 1 or higher if any file fails the test when testing + multiple files. + +'-v' +'--verbose' + Verbose mode. + When compressing, show the compression ratio and size for each file + processed. + When decompressing or testing, further -v's (up to 4) increase the + verbosity level, showing status, compression ratio, dictionary size, + trailer contents (CRC, data size, member size), and up to 6 bytes of + trailing data (if any) both in hexadecimal and as a string of printable + ASCII characters. + Two or more '-v' options show the progress of (de)compression. + +'-0 .. -9' + Compression level. Set the compression parameters (dictionary size and + match length limit) as shown in the table below. The default + compression level is '-6', equivalent to '-s8MiB -m36'. Note that '-9' + can be much slower than '-0'. These options have no effect when + decompressing, testing, or listing. + + The bidimensional parameter space of LZMA can't be mapped to a linear + scale optimal for all files. If your files are large, very repetitive, + etc, you may need to use the options '--dictionary-size' and + '--match-length' directly to achieve optimal performance. + + If several compression levels or '-s' or '-m' options are given, the + last setting is used. For example '-9 -s64MiB' is equivalent to + '-s64MiB -m273' + + Level Dictionary size (-s) Match length limit (-m) + -0 64 KiB 16 bytes + -1 1 MiB 5 bytes + -2 1.5 MiB 6 bytes + -3 2 MiB 8 bytes + -4 3 MiB 12 bytes + -5 4 MiB 20 bytes + -6 8 MiB 36 bytes + -7 16 MiB 68 bytes + -8 24 MiB 132 bytes + -9 32 MiB 273 bytes + +'--fast' +'--best' + Aliases for GNU gzip compatibility. + +'--empty-error' + Exit with error status 2 if any empty member is found in the input + files. + +'--marking-error' + Exit with error status 2 if the first LZMA byte is non-zero in any + member of the input files. This may be caused by data corruption or by + deliberate insertion of tracking information in the file. Use + 'lziprecover --clear-marking' to clear any such non-zero bytes. + +'--loose-trailing' + When decompressing, testing, or listing, allow trailing data whose + first bytes are so similar to the magic bytes of a lzip header that + they can be confused with a corrupt header. Use this option if a file + triggers a "corrupt header" error and the cause is not indeed a + corrupt header. + + + Numbers given as arguments to options may be expressed in decimal, +hexadecimal, or octal (using the same syntax as integer constants in C++), +and may be followed by a multiplier and an optional 'B' for "byte". + + Table of SI and binary prefixes (unit multipliers): + +Prefix Value | Prefix Value +k kilobyte (10^3 = 1000) | Ki kibibyte (2^10 = 1024) +M megabyte (10^6) | Mi mebibyte (2^20) +G gigabyte (10^9) | Gi gibibyte (2^30) +T terabyte (10^12) | Ti tebibyte (2^40) +P petabyte (10^15) | Pi pebibyte (2^50) +E exabyte (10^18) | Ei exbibyte (2^60) +Z zettabyte (10^21) | Zi zebibyte (2^70) +Y yottabyte (10^24) | Yi yobibyte (2^80) +R ronnabyte (10^27) | Ri robibyte (2^90) +Q quettabyte (10^30) | Qi quebibyte (2^100) + + + Exit status: 0 for a normal exit, 1 for environmental problems (file not +found, invalid command-line options, I/O errors, etc), 2 to indicate a +corrupt or invalid input file, 3 for an internal consistency error (e.g., +bug) which caused lzip to panic. + + +File: lzip.info, Node: Quality assurance, Next: Algorithm, Prev: Invoking lzip, Up: Top + +4 Design, development, and testing of lzip +****************************************** + +There are two ways of constructing a software design: One way is to make it +so simple that there are obviously no deficiencies and the other way is to +make it so complicated that there are no obvious deficiencies. The first +method is far more difficult. +-- C.A.R. Hoare + + Lzip has been designed, written, and tested with great care to replace +gzip and bzip2 as the standard general-purpose compressed format for +Unix-like systems. This chapter describes the lessons learned from these +previous formats, and their application to the design of lzip. The lzip +format specification has been reviewed carefully and is believed to be free +from design errors. + + +4.1 Format design +================= + +When gzip was designed in 1992, computers and operating systems were much +less capable than they are today. The designers of gzip tried to work around +some of those limitations, like 8.3 file names, with additional fields in +the file format. + + Today those limitations have mostly disappeared, and the format of gzip +has proved to be unnecessarily complicated. It includes fields that were +never used, others that have lost their usefulness, and finally others that +have become too limited. + + Bzip2 was designed 5 years later, and its format is simpler than the one +of gzip. + + Probably the worst defect of the gzip format from the point of view of +data safety is the variable size of its header. If the byte at offset 3 +(flags) of a gzip member gets corrupted, it may become difficult to recover +the data, even if the compressed blocks are intact, because it can't be +known with certainty where the compressed blocks begin. + + By contrast, the header of a lzip member has a fixed length of 6. The +LZMA stream in a lzip member always starts at offset 6, making it trivial to +recover the data even if the whole header becomes corrupt. + + Bzip2 also provides a header of fixed length and marks the begin and end +of each compressed block with six magic bytes, making it possible to find +the compressed blocks even in case of file damage. But bzip2 does not store +the size of each compressed block, as lzip does. + + Lziprecover is able to provide unique data recovery capabilities because +the lzip format is extraordinarily safe. The simple and safe design of the +file format complements the embedded error detection provided by the LZMA +data stream. Any distance larger than the dictionary size acts as a +forbidden symbol, allowing the decompressor to detect the approximate +position of errors, and leaving very little work for the check sequence +(CRC and data sizes) in the detection of errors. Lzip is usually able to +detect all possible bit flips in the compressed data without resorting to +the check sequence. It would be difficult to write an automatic recovery +tool like lziprecover for the gzip format. And, as far as I know, it has +never been written. + + Lzip, like gzip and bzip2, uses a CRC32 to check the integrity of the +decompressed data because it provides optimal accuracy in the detection of +errors up to a compressed size of about 16 GiB, a size larger than that of +most files. In the case of lzip, the additional detection capability of the +decompressor reduces the probability of undetected errors several million +times more, resulting in a combined integrity checking optimally accurate +for any member size produced by lzip. Preliminary results suggest that the +lzip format is safe enough to be used in critical safety avionics systems. + + The lzip format is designed for long-term archiving. Therefore it +excludes any unneeded features that may interfere with the future +extraction of the decompressed data. + + +4.1.1 Gzip format (mis)features not present in lzip +--------------------------------------------------- + +'Multiple algorithms' + Gzip provides a CM (Compression Method) field that has never been used + because it is a bad idea to begin with. New compression methods may + require additional fields, making it impossible to implement new + methods and, at the same time, keep the same format. This field does + not solve the problem of format proliferation; it just makes the + problem less obvious. + +'Optional fields in header' + Unless special precautions are taken, optional fields are generally a + bad idea because they produce a header of variable size. The gzip + header has 2 fields that, in addition to being optional, are + zero-terminated. This means that if any byte inside the field gets + zeroed, or if the terminating zero gets altered, gzip won't be able to + find neither the header CRC nor the compressed blocks. + +'Optional CRC for the header' + Using an optional CRC for the header is not only a bad idea, it is an + error; it circumvents the Hamming distance (HD) of the CRC and may + prevent the extraction of perfectly good data. For example, if the CRC + is used and the bit enabling it is reset by a bit flip, then the + header seems to be intact (in spite of being corrupt) while the + compressed blocks seem to be totally unrecoverable (in spite of being + intact). Very misleading indeed. + +'Metadata' + The gzip format stores some metadata, like the modification time of the + original file or the operating system on which compression took place. + This complicates reproducible compression (obtaining identical + compressed output from identical input). + + +4.1.2 Lzip format improvements over gzip and bzip2 +-------------------------------------------------- + +'64-bit size field' + Probably the most frequently reported shortcoming of the gzip format + is that it only stores the least significant 32 bits of the + uncompressed size. The size of any file larger or equal than 4 GiB + gets truncated. + + Bzip2 does not store the uncompressed size of the file. + + The lzip format provides a 64-bit field for the uncompressed size. + Additionally, lzip produces multimember output automatically when the + size is too large for a single member, allowing for an unlimited + uncompressed size. + +'Distributed index' + The lzip format provides a distributed index that, among other things, + helps plzip to decompress several times faster than pigz and helps + lziprecover do its job. Neither the gzip format nor the bzip2 format + do provide an index. + + A distributed index is safer and more scalable than a monolithic + index. The monolithic index introduces a single point of failure in + the compressed file and may limit the number of members or the total + uncompressed size. + + +4.2 Quality of implementation +============================= + +Our civilization depends critically on software; it had better be quality +software. +-- Bjarne Stroustrup + +'Accurate and robust error detection' + The lzip format provides 3-factor integrity checking, and the + decompressors report mismatches in each factor separately. This method + detects most false positives for corruption. If just one byte in one + factor fails but the other two factors match the data, it probably + means that the data are intact and the corruption just affects the + mismatching factor (CRC, data size, or member size) in the member + trailer. + +'Multiple implementations' + Just like the lzip format provides 3-factor protection against + undetected data corruption, the development methodology of the lzip + family of compressors provides 3-factor protection against undetected + programming errors. + + Three related but independent compressor implementations, lzip, clzip, + and minilzip/lzlib, are developed concurrently. Every stable release + of any of them is tested to check that it produces identical output to + the other two. This guarantees that all three implement the same + algorithm, and makes it unlikely that any of them may contain serious + undiscovered errors. In fact, no errors have been discovered in lzip + since 2009. + + Additionally, the three implementations have been extensively tested + with unzcrash, valgrind, and 'american fuzzy lop' without finding a + single vulnerability or false negative. *Note Unzcrash: + (lziprecover)Unzcrash. + +'Dictionary size' + Lzip automatically adapts the dictionary size to the size of each file. + In addition to reducing the amount of memory required for + decompression, this feature also minimizes the probability of being + affected by RAM errors during compression. + +'Exit status' + Returning a warning status of 2 is a design flaw of compress that + leaked into the design of gzip. Both bzip2 and lzip are free from this + flaw. + + + +File: lzip.info, Node: Algorithm, Next: File format, Prev: Quality assurance, Up: Top + +5 Algorithm +*********** + +In spite of its name (Lempel-Ziv-Markov chain-Algorithm), LZMA is not a +concrete algorithm; it is more like "any algorithm using the LZMA coding +scheme". LZMA compression consists in describing the uncompressed data as a +succession of coding sequences from the set shown in Section 'What is +coded' (*note what-is-coded::), and then encoding them using a range +encoder. For example, the option '-0' of lzip uses the scheme in almost the +simplest way possible; issuing the longest match it can find, or a literal +byte if it can't find a match. Inversely, a much more elaborated way of +finding coding sequences of minimum size than the one currently used by +lzip could be developed, and the resulting sequence could also be coded +using the LZMA coding scheme. + + Lzip currently implements two variants of the LZMA algorithm: fast (used +by option '-0') and normal (used by all other compression levels). + + The high compression of LZMA comes from combining two basic, well-proven +compression ideas: sliding dictionaries (LZ77) and Markov models (the thing +used by every compression algorithm that uses a range encoder or similar +order-0 entropy coder as its last stage) with segregation of contexts +according to what the bits are used for. + + Lzip is a two stage compressor. The first stage is a Lempel-Ziv coder, +which reduces redundancy by translating chunks of data to their +corresponding distance-length pairs. The second stage is a range encoder +that uses a different probability model for each type of data: distances, +lengths, literal bytes, etc. + + Here is how it works, step by step: + + 1) The member header is written to the output stream. + + 2) The first byte is coded literally, because there are no previous +bytes to which the match finder can refer to. + + 3) The main encoder advances to the next byte in the input data and +calls the match finder. + + 4) The match finder fills an array with the minimum distances before the +current byte where a match of a given length can be found. + + 5) Go back to step 3 until a sequence (formed of pairs, repeated +distances, and literal bytes) of minimum price has been formed. Where the +price represents the number of output bits produced. + + 6) The range encoder encodes the sequence produced by the main encoder +and sends the bytes produced to the output stream. + + 7) Go back to step 3 until the input data are finished or until the +member or volume size limits are reached. + + 8) The range encoder is flushed. + + 9) The member trailer is written to the output stream. + + 10) If there are more data to compress, go back to step 1. + + + During compression, lzip reads data in large blocks (one dictionary size +at a time). Therefore it may block for up to tens of seconds any process +feeding data to it through a pipe. This is normal. The blocking intervals +get longer with higher compression levels because dictionary size increases +(and compression speed decreases) with compression level. + +The ideas embodied in lzip are due to (at least) the following people: +Abraham Lempel and Jacob Ziv (for the LZ algorithm), Andrei Markov (for the +definition of Markov chains), G.N.N. Martin (for the definition of range +encoding), Igor Pavlov (for putting all the above together in LZMA), and +Julian Seward (for bzip2's CLI). + + +File: lzip.info, Node: File format, Next: Stream format, Prev: Algorithm, Up: Top + +6 File format +************* + +Perfection is reached, not when there is no longer anything to add, but +when there is no longer anything to take away. +-- Antoine de Saint-Exupery + + + In the diagram below, a box like this: + ++---+ +| | <-- the vertical bars might be missing ++---+ + + represents one byte; a box like this: + ++==============+ +| | ++==============+ + + represents a variable number of bytes. + + + A lzip file consists of one or more independent "members" (compressed +data sets). The members simply appear one after another in the file, with no +additional information before, between, or after them. Each member can +encode in compressed form up to 16 EiB - 1 byte of uncompressed data. The +size of a multimember file is unlimited. + + Each member has the following structure: + ++--+--+--+--+----+----+=============+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +| ID string | VN | DS | LZMA stream | CRC32 | Data size | Member size | ++--+--+--+--+----+----+=============+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + All multibyte values are stored in little endian order. + +'ID string (the "magic" bytes)' + A four byte string, identifying the lzip format, with the value "LZIP" + (0x4C, 0x5A, 0x49, 0x50). + +'VN (version number, 1 byte)' + Just in case something needs to be modified in the future. 1 for now. + +'DS (coded dictionary size, 1 byte)' + The dictionary size is calculated by taking a power of 2 (the base + size) and subtracting from it a fraction between 0/16 and 7/16 of the + base size. + Bits 4-0 contain the base 2 logarithm of the base size (12 to 29). + Bits 7-5 contain the numerator of the fraction (0 to 7) to subtract + from the base size to obtain the dictionary size. + Example: 0xD3 = 2^19 - 6 * 2^15 = 512 KiB - 6 * 32 KiB = 320 KiB + Valid values for dictionary size range from 4 KiB to 512 MiB. + +'LZMA stream' + The LZMA stream, finished by an "End Of Stream" marker. Uses default + values for encoder properties. *Note Stream format::, for a complete + description. + +'CRC32 (4 bytes)' + Cyclic Redundancy Check (CRC) of the original uncompressed data. + +'Data size (8 bytes)' + Size of the original uncompressed data. + +'Member size (8 bytes)' + Total size of the member, including header and trailer. This field acts + as a distributed index, improves the checking of stream integrity, and + facilitates the safe recovery of undamaged members from multimember + files. Lzip limits the member size to 2 PiB to prevent the data size + field from overflowing. + + + +File: lzip.info, Node: Stream format, Next: Trailing data, Prev: File format, Up: Top + +7 Format of the LZMA stream in lzip files +***************************************** + +The LZMA algorithm has three parameters, called "special LZMA properties", +to adjust it for some kinds of binary data. These parameters are: +'literal_context_bits' (with a default value of 3), +'literal_pos_state_bits' (with a default value of 0), and 'pos_state_bits' +(with a default value of 2). As a general purpose compressor, lzip only +uses the default values for these parameters. In particular +'literal_pos_state_bits' has been optimized away and does not even appear +in the code. + + Lzip finishes the LZMA stream with an "End Of Stream" (EOS) marker (the +distance-length pair 0xFFFFFFFFU, 2), which in conjunction with the 'member +size' field in the member trailer allows the checking of stream integrity. +The EOS marker is the only LZMA marker allowed in lzip files. The LZMA +stream in lzip files always has these two features (default properties and +EOS marker) and is referred to in this document as LZMA-302eos. This +simplified and marker-terminated form of the LZMA stream format has been +chosen to maximize interoperability and safety. + + The second stage of LZMA is a range encoder that uses a different +probability model for each type of symbol: distances, lengths, literal +bytes, etc. Range encoding conceptually encodes all the symbols of the +message into one number. Unlike Huffman coding, which assigns to each +symbol a bit-pattern and concatenates all the bit-patterns together, range +encoding can compress one symbol to less than one bit. Therefore the +compressed data produced by a range encoder can't be split in pieces that +could be described individually. + + It seems that the only way of describing the LZMA-302eos stream is to +describe the algorithm that decodes it. And given the many details about +the range decoder that need to be described accurately, the source code of +a real decompressor seems the only appropriate reference to use. + + What follows is a description of the decoding algorithm for LZMA-302eos +streams using as reference the source code of "lzd", an educational +decompressor for lzip files, included in appendix A. *Note Reference source +code::. Lzd is written in C++11 and can be downloaded from the lzip download +directory. + + +7.1 What is coded +================= + +The LZMA stream includes literals, matches, and repeated matches (matches +reusing a recently used distance). There are 7 different coding sequences: + +Bit sequence Name Description +----------------------------------------------------------------------------- +0 + byte literal literal byte +1 + 0 + len + dis match distance-length pair +1 + 1 + 0 + 0 shortrep 1 byte match at latest used distance +1 + 1 + 0 + 1 + len rep0 len bytes match at latest used distance +1 + 1 + 1 + 0 + len rep1 len bytes match at second latest used + distance +1 + 1 + 1 + 1 + 0 + len rep2 len bytes match at third latest used + distance +1 + 1 + 1 + 1 + 1 + len rep3 len bytes match at fourth latest used + distance + + + In the following tables, multibit sequences are coded in normal order, +from most significant bit (MSB) to least significant bit (LSB), except +where noted otherwise. + + Lengths (the 'len' in the table above) are coded as follows: + +Bit sequence Description +---------------------------------------------------------------------------- +0 + 3 bits lengths from 2 to 9 +1 + 0 + 3 bits lengths from 10 to 17 +1 + 1 + 8 bits lengths from 18 to 273 + + + The coding of distances is a little more complicated, so I'll begin by +explaining a simpler version of the encoding. + + Imagine you need to encode a number from 0 to 2^32 - 1, and you want to +do it in a way that produces shorter codes for the smaller numbers. You may +first encode the position of the most significant bit that is set to 1, +which you may find by making a bit scan from the left (from the MSB). A +position of 0 means that the number is 0 (no bit is set), 1 means the LSB is +the first bit set (the number is 1), and 32 means the MSB is set (i.e., the +number is >= 0x80000000). Then, if the position is >= 2, you encode the +remaining position - 1 bits. Let's call these bits "direct bits" because +they are coded directly by value instead of indirectly by position. + + The inconvenient of this simple method is that it needs 6 bits to encode +the position, but it just uses 33 of the 64 possible values, wasting almost +half of the codes. + + The intelligent trick of LZMA is that it encodes in what it calls a +"slot" the position of the most significant bit set, along with the value +of the next bit, using the same 6 bits that would take to encode the +position alone. This seems to need 66 slots (twice the number of +positions), but for positions 0 and 1 there is no next bit, so the number +of slots needed is 64 (0 to 63). + + The 6 bits representing this "slot number" are then context-coded. If +the distance is >= 4, the remaining bits are encoded as follows. +'direct_bits' is the amount of remaining bits (from 1 to 30) needed to form +a complete distance, and is calculated as (slot >> 1) - 1. If a distance +needs 6 or more direct_bits, the last 4 bits are encoded separately. The +last piece (all the direct_bits for distances 4 to 127 (slots 4 to 13), or +the last 4 bits for distances >= 128 (slot >= 14)) is context-coded in +reverse order (from LSB to MSB). For distances >= 128, the +'direct_bits - 4' part is encoded with fixed 0.5 probability. + +Bit sequence Description +---------------------------------------------------------------------------- +slot distances from 0 to 3 +slot + direct_bits distances from 4 to 127 +slot + (direct_bits - 4) + 4 bits distances from 128 to 2^32 - 1 + + +7.2 The coding contexts +======================= + +These contexts ('Bit_model' in the source), are integers or arrays of +integers representing the probability of the corresponding bit being 0. + + The indices used in these arrays are: + +'state' + A state machine ('State' in the source) with 12 states (0 to 11), + coding the latest 2 to 4 types of sequences processed. The initial + state is 0. + +'pos_state' + Value of the 2 least significant bits of the current position in the + decoded data. + +'literal_state' + Value of the 3 most significant bits of the latest byte decoded. + +'len_state' + Coded value of the current match length (length - 2), with a maximum + of 3. The resulting value is in the range 0 to 3. + + + The types of previous sequences corresponding to each state are shown in +the following table. '!literal' is any sequence except a literal byte. +'rep' is any one of 'rep0', 'rep1', 'rep2', or 'rep3'. The last type in +each line is the most recent. + +State Types of previous sequences +------------------------------------------------------ +0 literal, literal, literal +1 match, literal, literal +2 rep or (!literal, shortrep), literal, literal +3 literal, shortrep, literal, literal +4 match, literal +5 rep or (!literal, shortrep), literal +6 literal, shortrep, literal +7 literal, match +8 literal, rep +9 literal, shortrep +10 !literal, match +11 !literal, (rep or shortrep) + + + The contexts for decoding the type of coding sequence are: + +Name Indices Used when +---------------------------------------------------------------------------- +bm_match state, pos_state sequence start +bm_rep state after sequence 1 +bm_rep0 state after sequence 11 +bm_rep1 state after sequence 111 +bm_rep2 state after sequence 1111 +bm_len state, pos_state after sequence 110 + + + The contexts for decoding distances are: + +Name Indices Used when +---------------------------------------------------------------------------- +bm_dis_slot len_state, bit tree distance start +bm_dis reverse bit tree after slots 4 to 13 +bm_align reverse bit tree for distances >= 128, after fixed + probability bits + + + There are two separate sets of contexts for lengths ('Len_model' in the +source). One for normal matches, the other for repeated matches. The +contexts in each Len_model are (see 'decode_len' in the source): + +Name Indices Used when +--------------------------------------------------------------------------- +choice1 none length start +choice2 none after sequence 1 +bm_low pos_state, bit tree after sequence 0 +bm_mid pos_state, bit tree after sequence 10 +bm_high bit tree after sequence 11 + + + The context array 'bm_literal' is special. In principle it acts as a +normal bit tree context, the one selected by 'literal_state'. But if the +previous decoded byte was not a literal, two other bit tree contexts are +used depending on the value of each bit in 'match_byte' (the byte at the +latest used distance), until a bit is decoded that is different from its +corresponding bit in 'match_byte'. After the first difference is found, the +rest of the byte is decoded using the normal bit tree context. (See +'decode_matched' in the source). + + +7.3 The range decoder +===================== + +The LZMA stream is consumed one byte at a time by the range decoder. (See +'normalize' in the source). Every byte consumed produces a variable number +of decoded bits, depending on how well these bits agree with their context. +(See 'decode_bit' in the source). + + The range decoder state consists of two unsigned 32-bit variables: +'range' (representing the most significant part of the range size not yet +decoded) and 'code' (representing the current point within 'range'). +'range' is initialized to 2^32 - 1, and 'code' is initialized to 0. + + The range encoder produces a first 0 byte that must be ignored by the +range decoder. (See the 'Range_decoder' constructor in the source). + + +7.4 Decoding and checking the LZMA stream +========================================= + +After decoding the member header and obtaining the dictionary size, the +range decoder is initialized and then the LZMA decoder enters a loop (see +'decode_member' in the source) where it invokes the range decoder with the +appropriate contexts to decode the different coding sequences (matches, +repeated matches, and literal bytes), until the "End Of Stream" marker is +decoded. + + Once the "End Of Stream" marker has been decoded, the decompressor reads +and decodes the member trailer, and checks that the three integrity factors +stored there (CRC, data size, and member size) match those computed from the +data. + + +File: lzip.info, Node: Trailing data, Next: Examples, Prev: Stream format, Up: Top + +8 Extra data appended to the file +********************************* + +Sometimes extra data are found appended to a lzip file after the last +member. Such trailing data may be: + + * Padding added to make the file size a multiple of some block size, for + example when writing to a tape. It is safe to append any amount of + padding zero bytes to a lzip file. + + * Useful data added by the user; an "End Of File" string (to check that + the file has not been truncated), a cryptographically secure hash, a + description of file contents, etc. It is safe to append any amount of + text to a lzip file as long as none of the first four bytes of the + text matches the corresponding byte in the string "LZIP", and the text + does not contain any zero bytes (null characters). Nonzero bytes and + zero bytes can't be safely mixed in trailing data. + + * Garbage added by some not totally successful copy operation. + + * Malicious data added to the file in order to make its total size and + hash value (for a chosen hash) coincide with those of another file. + + * In rare cases, trailing data could be the corrupt header of another + member. In multimember or concatenated files the probability of + corruption happening in the magic bytes is 5 times smaller than the + probability of getting a false positive caused by the corruption of the + integrity information itself. Therefore it can be considered to be + below the noise level. Additionally, the test used by lzip to + discriminate trailing data from a corrupt header has a Hamming + distance (HD) of 3, and the 3 bit flips must happen in different magic + bytes for the test to fail. In any case, the option '--trailing-error' + guarantees that any corrupt header is detected. + + Trailing data are in no way part of the lzip file format, but tools +reading lzip files are expected to behave as correctly and usefully as +possible in the presence of trailing data. + + Trailing data can be safely ignored in most cases. In some cases, like +that of user-added data, they are expected to be ignored. In those cases +where a file containing trailing data must be rejected, the option +'--trailing-error' can be used. *Note --trailing-error::. + + +File: lzip.info, Node: Examples, Next: Problems, Prev: Trailing data, Up: Top + +9 A small tutorial with examples +******************************** + +WARNING! Even if lzip is bug-free, other causes may result in a corrupt +compressed file (bugs in the system libraries, memory errors, etc). +Therefore, if the data you are going to compress are important, give the +option '--keep' to lzip and don't remove the original file until you check +the compressed file with a command like 'lzip -cd file.lz | cmp file -'. +Most RAM errors happening during compression can only be detected by +comparing the compressed file with the original because the corruption +happens before lzip compresses the RAM contents, resulting in a valid +compressed file containing wrong data. + + +Example 1: Extract all the files from archive 'foo.tar.lz'. + + tar -xf foo.tar.lz + or + lzip -cd foo.tar.lz | tar -xf - + + +Example 2: Replace a regular file with its compressed version 'file.lz' and +show the compression ratio. + + lzip -v file + + +Example 3: Like example 2 but the created 'file.lz' is multimember with a +member size of 1 MiB. The compression ratio is not shown. + + lzip -b 1MiB file + + +Example 4: Restore a regular file from its compressed version 'file.lz'. If +the operation is successful, 'file.lz' is removed. + + lzip -d file.lz + + +Example 5: Check the integrity of the compressed file 'file.lz' and show +status. + + lzip -tv file.lz + + +Example 6: The right way of concatenating the decompressed output of two or +more compressed files. *Note Trailing data::. + + Don't do this + cat file1.lz file2.lz file3.lz | lzip -d - + Do this instead + lzip -cd file1.lz file2.lz file3.lz + + +Example 7: Decompress 'file.lz' partially until 10 KiB of decompressed data +are produced. + + lzip -cd file.lz | dd bs=1024 count=10 + + +Example 8: Decompress 'file.lz' partially from decompressed byte at offset +10000 to decompressed byte at offset 14999 (5000 bytes are produced). + + lzip -cd file.lz | dd bs=1000 skip=10 count=5 + + +Example 9: Compress a whole device in /dev/sdc and send the output to +'file.lz'. + + lzip -c /dev/sdc > file.lz + or + lzip /dev/sdc -o file.lz + + +Example 10: Create a multivolume compressed tar archive with a volume size +of 1440 KiB. + + tar -c some_directory | lzip -S 1440KiB -o volume_name - + + +Example 11: Extract a multivolume compressed tar archive. + + lzip -cd volume_name*.lz | tar -xf - + + +Example 12: Create a multivolume compressed backup of a large database file +with a volume size of 650 MB, where each volume is a multimember file with +a member size of 32 MiB. + + lzip -b 32MiB -S 650MB big_db + + +File: lzip.info, Node: Problems, Next: Reference source code, Prev: Examples, Up: Top + +10 Reporting bugs +***************** + +There are probably bugs in lzip. There are certainly errors and omissions +in this manual. If you report them, they will get fixed. If you don't, no +one will ever know about them and they will remain unfixed for all +eternity, if not longer. + + If you find a bug in lzip, please send electronic mail to +. Include the version number, which you can find by +running 'lzip --version'. + + +File: lzip.info, Node: Reference source code, Next: Concept index, Prev: Problems, Up: Top + +Appendix A Reference source code +******************************** + +/* Lzd - Educational decompressor for the lzip format + Copyright (C) 2013-2024 Antonio Diaz Diaz. + + This program is free software. Redistribution and use in source and + binary forms, with or without modification, are permitted provided + that the following conditions are met: + + 1. Redistributions of source code must retain the above copyright + notice, this list of conditions, and the following disclaimer. + + 2. Redistributions in binary form must reproduce the above copyright + notice, this list of conditions, and the following disclaimer in the + documentation and/or other materials provided with the distribution. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. +*/ +/* + Exit status: 0 for a normal exit, 1 for environmental problems + (file not found, invalid command-line options, I/O errors, etc), 2 to + indicate a corrupt or invalid input file. +*/ + +#include +#include +#include +#include +#include +#include +#include +#if defined __MSVCRT__ || defined __OS2__ || defined __DJGPP__ +#include +#include +#endif + + +class State + { + int st; + +public: + enum { states = 12 }; + State() : st( 0 ) {} + int operator()() const { return st; } + bool is_char() const { return st < 7; } + + void set_char() + { + const int next[states] = { 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 4, 5 }; + st = next[st]; + } + void set_match() { st = ( st < 7 ) ? 7 : 10; } + void set_rep() { st = ( st < 7 ) ? 8 : 11; } + void set_short_rep() { st = ( st < 7 ) ? 9 : 11; } + }; + + +enum { + min_dictionary_size = 1 << 12, + max_dictionary_size = 1 << 29, + literal_context_bits = 3, + literal_pos_state_bits = 0, // not used + pos_state_bits = 2, + pos_states = 1 << pos_state_bits, + pos_state_mask = pos_states - 1, + + len_states = 4, + dis_slot_bits = 6, + start_dis_model = 4, + end_dis_model = 14, + modeled_distances = 1 << ( end_dis_model / 2 ), // 128 + dis_align_bits = 4, + dis_align_size = 1 << dis_align_bits, + + len_low_bits = 3, + len_mid_bits = 3, + len_high_bits = 8, + len_low_symbols = 1 << len_low_bits, + len_mid_symbols = 1 << len_mid_bits, + len_high_symbols = 1 << len_high_bits, + max_len_symbols = len_low_symbols + len_mid_symbols + len_high_symbols, + + min_match_len = 2, // must be 2 + + bit_model_move_bits = 5, + bit_model_total_bits = 11, + bit_model_total = 1 << bit_model_total_bits }; + +struct Bit_model + { + int probability; + Bit_model() : probability( bit_model_total / 2 ) {} + }; + +struct Len_model + { + Bit_model choice1; + Bit_model choice2; + Bit_model bm_low[pos_states][len_low_symbols]; + Bit_model bm_mid[pos_states][len_mid_symbols]; + Bit_model bm_high[len_high_symbols]; + }; + + +class CRC32 + { + uint32_t data[256]; // Table of CRCs of all 8-bit messages. + +public: + CRC32() + { + for( unsigned n = 0; n < 256; ++n ) + { + unsigned c = n; + for( int k = 0; k < 8; ++k ) + { if( c & 1 ) c = 0xEDB88320U ^ ( c >> 1 ); else c >>= 1; } + data[n] = c; + } + } + + void update_buf( uint32_t & crc, const uint8_t * const buffer, + const int size ) const + { + for( int i = 0; i < size; ++i ) + crc = data[(crc^buffer[i])&0xFF] ^ ( crc >> 8 ); + } + }; + +const CRC32 crc32; + + +enum { header_size = 6, trailer_size = 20 }; +typedef uint8_t Lzip_header[header_size]; // 0-3 magic bytes + // 4 version + // 5 coded dictionary size +typedef uint8_t Lzip_trailer[trailer_size]; + // 0-3 CRC32 of the uncompressed data + // 4-11 size of the uncompressed data + // 12-19 member size including header and trailer + +class Range_decoder + { + unsigned long long member_pos; + uint32_t code; + uint32_t range; + +public: + Range_decoder() + : member_pos( header_size ), code( 0 ), range( 0xFFFFFFFFU ) + { + get_byte(); // discard first byte of the LZMA stream + for( int i = 0; i < 4; ++i ) code = ( code << 8 ) | get_byte(); + } + + uint8_t get_byte() { ++member_pos; return std::getc( stdin ); } + unsigned long long member_position() const { return member_pos; } + + unsigned decode( const int num_bits ) + { + unsigned symbol = 0; + for( int i = num_bits; i > 0; --i ) + { + range >>= 1; + symbol <<= 1; + if( code >= range ) { code -= range; symbol |= 1; } + if( range <= 0x00FFFFFFU ) // normalize + { range <<= 8; code = ( code << 8 ) | get_byte(); } + } + return symbol; + } + + bool decode_bit( Bit_model & bm ) + { + bool symbol; + const uint32_t bound = ( range >> bit_model_total_bits ) * bm.probability; + if( code < bound ) + { + range = bound; + bm.probability += + ( bit_model_total - bm.probability ) >> bit_model_move_bits; + symbol = 0; + } + else + { + code -= bound; + range -= bound; + bm.probability -= bm.probability >> bit_model_move_bits; + symbol = 1; + } + if( range <= 0x00FFFFFFU ) // normalize + { range <<= 8; code = ( code << 8 ) | get_byte(); } + return symbol; + } + + unsigned decode_tree( Bit_model bm[], const int num_bits ) + { + unsigned symbol = 1; + for( int i = 0; i < num_bits; ++i ) + symbol = ( symbol << 1 ) | decode_bit( bm[symbol] ); + return symbol - ( 1 << num_bits ); + } + + unsigned decode_tree_reversed( Bit_model bm[], const int num_bits ) + { + unsigned symbol = decode_tree( bm, num_bits ); + unsigned reversed_symbol = 0; + for( int i = 0; i < num_bits; ++i ) + { + reversed_symbol = ( reversed_symbol << 1 ) | ( symbol & 1 ); + symbol >>= 1; + } + return reversed_symbol; + } + + unsigned decode_matched( Bit_model bm[], const unsigned match_byte ) + { + unsigned symbol = 1; + for( int i = 7; i >= 0; --i ) + { + const bool match_bit = ( match_byte >> i ) & 1; + const bool bit = decode_bit( bm[symbol+(match_bit<<8)+0x100] ); + symbol = ( symbol << 1 ) | bit; + if( match_bit != bit ) + { + while( symbol < 0x100 ) + symbol = ( symbol << 1 ) | decode_bit( bm[symbol] ); + break; + } + } + return symbol & 0xFF; + } + + unsigned decode_len( Len_model & lm, const int pos_state ) + { + if( decode_bit( lm.choice1 ) == 0 ) + return min_match_len + + decode_tree( lm.bm_low[pos_state], len_low_bits ); + if( decode_bit( lm.choice2 ) == 0 ) + return min_match_len + len_low_symbols + + decode_tree( lm.bm_mid[pos_state], len_mid_bits ); + return min_match_len + len_low_symbols + len_mid_symbols + + decode_tree( lm.bm_high, len_high_bits ); + } + }; + + +class LZ_decoder + { + unsigned long long partial_data_pos; + Range_decoder rdec; + const unsigned dictionary_size; + uint8_t * const buffer; // output buffer + unsigned pos; // current pos in buffer + unsigned stream_pos; // first byte not yet written to stdout + uint32_t crc_; + bool pos_wrapped; + + void flush_data(); + + uint8_t peek( const unsigned distance ) const + { + if( pos > distance ) return buffer[pos - distance - 1]; + if( pos_wrapped ) return buffer[dictionary_size + pos - distance - 1]; + return 0; // prev_byte of first byte + } + + void put_byte( const uint8_t b ) + { + buffer[pos] = b; + if( ++pos >= dictionary_size ) flush_data(); + } + +public: + explicit LZ_decoder( const unsigned dict_size ) + : + partial_data_pos( 0 ), + dictionary_size( dict_size ), + buffer( new uint8_t[dictionary_size] ), + pos( 0 ), + stream_pos( 0 ), + crc_( 0xFFFFFFFFU ), + pos_wrapped( false ) + {} + + ~LZ_decoder() { delete[] buffer; } + + unsigned crc() const { return crc_ ^ 0xFFFFFFFFU; } + unsigned long long data_position() const + { return partial_data_pos + pos; } + uint8_t get_byte() { return rdec.get_byte(); } + unsigned long long member_position() const + { return rdec.member_position(); } + + bool decode_member(); + }; + + +void LZ_decoder::flush_data() + { + if( pos > stream_pos ) + { + const unsigned size = pos - stream_pos; + crc32.update_buf( crc_, buffer + stream_pos, size ); + if( std::fwrite( buffer + stream_pos, 1, size, stdout ) != size ) + { std::fprintf( stderr, "Write error: %s\n", std::strerror( errno ) ); + std::exit( 1 ); } + if( pos >= dictionary_size ) + { partial_data_pos += pos; pos = 0; pos_wrapped = true; } + stream_pos = pos; + } + } + + +bool LZ_decoder::decode_member() // Return false if error + { + Bit_model bm_literal[1<> ( 8 - literal_context_bits ); + Bit_model * const bm = bm_literal[literal_state]; + if( state.is_char() ) + put_byte( rdec.decode_tree( bm, 8 ) ); + else + put_byte( rdec.decode_matched( bm, peek( rep0 ) ) ); + state.set_char(); + continue; + } + // match or repeated match + int len; + if( rdec.decode_bit( bm_rep[state()] ) != 0 ) // 2nd bit + { + if( rdec.decode_bit( bm_rep0[state()] ) == 0 ) // 3rd bit + { + if( rdec.decode_bit( bm_len[state()][pos_state] ) == 0 ) // 4th bit + { state.set_short_rep(); put_byte( peek( rep0 ) ); continue; } + } + else + { + unsigned distance; + if( rdec.decode_bit( bm_rep1[state()] ) == 0 ) // 4th bit + distance = rep1; + else + { + if( rdec.decode_bit( bm_rep2[state()] ) == 0 ) // 5th bit + distance = rep2; + else + { distance = rep3; rep3 = rep2; } + rep2 = rep1; + } + rep1 = rep0; + rep0 = distance; + } + state.set_rep(); + len = rdec.decode_len( rep_len_model, pos_state ); + } + else // match + { + rep3 = rep2; rep2 = rep1; rep1 = rep0; + len = rdec.decode_len( match_len_model, pos_state ); + const int len_state = std::min( len - min_match_len, len_states - 1 ); + rep0 = rdec.decode_tree( bm_dis_slot[len_state], dis_slot_bits ); + if( rep0 >= start_dis_model ) + { + const unsigned dis_slot = rep0; + const int direct_bits = ( dis_slot >> 1 ) - 1; + rep0 = ( 2 | ( dis_slot & 1 ) ) << direct_bits; + if( dis_slot < end_dis_model ) + rep0 += rdec.decode_tree_reversed( bm_dis + ( rep0 - dis_slot ), + direct_bits ); + else + { + rep0 += + rdec.decode( direct_bits - dis_align_bits ) << dis_align_bits; + rep0 += rdec.decode_tree_reversed( bm_align, dis_align_bits ); + if( rep0 == 0xFFFFFFFFU ) // marker found + { + flush_data(); + return len == min_match_len; // End Of Stream marker + } + } + } + state.set_match(); + if( rep0 >= dictionary_size || ( rep0 >= pos && !pos_wrapped ) ) + { flush_data(); return false; } + } + for( int i = 0; i < len; ++i ) put_byte( peek( rep0 ) ); + } + flush_data(); + return false; + } + + +int main( const int argc, const char * const argv[] ) + { + if( argc > 2 || ( argc == 2 && std::strcmp( argv[1], "-d" ) != 0 ) ) + { + std::printf( + "Lzd %s - Educational decompressor for the lzip format.\n" + "Study the source code to learn how a lzip decompressor works.\n" + "See the lzip manual for an explanation of the code.\n" + "\nUsage: %s [-d] < file.lz > file\n" + "Lzd decompresses from standard input to standard output.\n" + "\nCopyright (C) 2024 Antonio Diaz Diaz.\n" + "License 2-clause BSD.\n" + "This is free software: you are free to change and redistribute it.\n" + "There is NO WARRANTY, to the extent permitted by law.\n" + "Report bugs to lzip-bug@nongnu.org\n" + "Lzd home page: http://www.nongnu.org/lzip/lzd.html\n", + PROGVERSION, argv[0] ); + return 0; + } + +#if defined __MSVCRT__ || defined __OS2__ || defined __DJGPP__ + setmode( STDIN_FILENO, O_BINARY ); + setmode( STDOUT_FILENO, O_BINARY ); +#endif + + for( bool first_member = true; ; first_member = false ) + { + Lzip_header header; // check header + for( int i = 0; i < header_size; ++i ) header[i] = std::getc( stdin ); + if( std::feof( stdin ) || std::memcmp( header, "LZIP\x01", 5 ) != 0 ) + { + if( first_member ) + { std::fputs( "Bad magic number (file not in lzip format).\n", + stderr ); return 2; } + break; // ignore trailing data + } + unsigned dict_size = 1 << ( header[5] & 0x1F ); + dict_size -= ( dict_size / 16 ) * ( ( header[5] >> 5 ) & 7 ); + if( dict_size < min_dictionary_size || dict_size > max_dictionary_size ) + { std::fputs( "Invalid dictionary size in member header.\n", stderr ); + return 2; } + + LZ_decoder decoder( dict_size ); // decode LZMA stream + if( !decoder.decode_member() ) + { std::fputs( "Data error\n", stderr ); return 2; } + + Lzip_trailer trailer; // check trailer + for( int i = 0; i < trailer_size; ++i ) trailer[i] = decoder.get_byte(); + int retval = 0; + unsigned crc = 0; + for( int i = 3; i >= 0; --i ) crc = ( crc << 8 ) + trailer[i]; + if( crc != decoder.crc() ) + { std::fputs( "CRC mismatch\n", stderr ); retval = 2; } + + unsigned long long data_size = 0; + for( int i = 11; i >= 4; --i ) + data_size = ( data_size << 8 ) + trailer[i]; + if( data_size != decoder.data_position() ) + { std::fputs( "Data size mismatch\n", stderr ); retval = 2; } + + unsigned long long member_size = 0; + for( int i = 19; i >= 12; --i ) + member_size = ( member_size << 8 ) + trailer[i]; + if( member_size != decoder.member_position() ) + { std::fputs( "Member size mismatch\n", stderr ); retval = 2; } + if( retval ) return retval; + } + + if( std::fclose( stdout ) != 0 ) + { std::fprintf( stderr, "Error closing stdout: %s\n", + std::strerror( errno ) ); return 1; } + return 0; + } + + +File: lzip.info, Node: Concept index, Prev: Reference source code, Up: Top + +Concept index +************* + +[index] +* Menu: + +* algorithm: Algorithm. (line 6) +* bugs: Problems. (line 6) +* examples: Examples. (line 6) +* file format: File format. (line 6) +* format of the LZMA stream: Stream format. (line 6) +* getting help: Problems. (line 6) +* introduction: Introduction. (line 6) +* invoking: Invoking lzip. (line 6) +* options: Invoking lzip. (line 6) +* output: Output. (line 6) +* quality assurance: Quality assurance. (line 6) +* reference source code: Reference source code. (line 6) +* trailing data: Trailing data. (line 6) +* usage: Invoking lzip. (line 6) +* version: Invoking lzip. (line 6) + + + +Tag Table: +Node: Top203 +Node: Introduction1197 +Node: Output7082 +Node: Invoking lzip8677 +Ref: --trailing-error9546 +Node: Quality assurance19644 +Node: Algorithm28457 +Node: File format31858 +Ref: coded-dict-size33287 +Node: Stream format34518 +Ref: what-is-coded36913 +Node: Trailing data45787 +Node: Examples48123 +Ref: concat-example49563 +Node: Problems50784 +Node: Reference source code51316 +Node: Concept index66361 + +End Tag Table + + +Local Variables: +coding: iso-8859-15 +End: diff --git a/doc/lzip.texi b/doc/lzip.texi new file mode 100644 index 0000000..865a413 --- /dev/null +++ b/doc/lzip.texi @@ -0,0 +1,1800 @@ +\input texinfo @c -*-texinfo-*- +@c %**start of header +@setfilename lzip.info +@documentencoding ISO-8859-15 +@settitle Lzip Manual +@finalout +@c %**end of header + +@set UPDATED 1 March 2024 +@set VERSION 1.24.1 + +@dircategory Compression +@direntry +* Lzip: (lzip). LZMA lossless data compressor +@end direntry + + +@ifnothtml +@titlepage +@title Lzip +@subtitle LZMA lossless data compressor +@subtitle for Lzip version @value{VERSION}, @value{UPDATED} +@author by Antonio Diaz Diaz + +@page +@vskip 0pt plus 1filll +@end titlepage + +@contents +@end ifnothtml + +@ifnottex +@node Top +@top + +This manual is for Lzip (version @value{VERSION}, @value{UPDATED}). + +@menu +* Introduction:: Purpose and features of lzip +* Output:: Meaning of lzip's output +* Invoking lzip:: Command-line interface +* Quality assurance:: Design, development, and testing of lzip +* Algorithm:: How lzip compresses the data +* File format:: Detailed format of the compressed file +* Stream format:: Format of the LZMA stream in lzip files +* Trailing data:: Extra data appended to the file +* Examples:: A small tutorial with examples +* Problems:: Reporting bugs +* Reference source code:: Source code illustrating stream format +* Concept index:: Index of concepts +@end menu + +@sp 1 +Copyright @copyright{} 2008-2024 Antonio Diaz Diaz. + +This manual is free documentation: you have unlimited permission to copy, +distribute, and modify it. +@end ifnottex + + +@node Introduction +@chapter Introduction +@cindex introduction + +@uref{http://www.nongnu.org/lzip/lzip.html,,Lzip} +is a lossless data compressor with a user interface similar to the one +of gzip or bzip2. Lzip uses a simplified form of the 'Lempel-Ziv-Markov +chain-Algorithm' (LZMA) stream format to maximize interoperability. The +maximum dictionary size is 512 MiB so that any lzip file can be decompressed +on 32-bit machines. Lzip provides accurate and robust 3-factor integrity +checking. Lzip can compress about as fast as gzip @w{(lzip -0)} or compress most +files more than bzip2 @w{(lzip -9)}. Decompression speed is intermediate between +gzip and bzip2. Lzip is better than gzip and bzip2 from a data recovery +perspective. Lzip has been designed, written, and tested with great care to +replace gzip and bzip2 as the standard general-purpose compressed format for +Unix-like systems. + +For compressing/decompressing large files on multiprocessor machines +@uref{http://www.nongnu.org/lzip/manual/plzip_manual.html,,plzip} can be +much faster than lzip at the cost of a slightly reduced compression ratio. +@ifnothtml +@xref{Top,plzip manual,,plzip}. +@end ifnothtml + +For creation and manipulation of compressed tar archives +@uref{http://www.nongnu.org/lzip/manual/tarlz_manual.html,,tarlz} can be more +efficient than using tar and plzip because tarlz is able to keep the +alignment between tar members and lzip members. +@ifnothtml +@xref{Top,tarlz manual,,tarlz}. +@end ifnothtml + +The lzip file format is designed for data sharing and long-term archiving, +taking into account both data integrity and decoder availability: + +@itemize @bullet +@item +The lzip format provides very safe integrity checking and some data +recovery means. The program +@uref{http://www.nongnu.org/lzip/manual/lziprecover_manual.html#Data-safety,,lziprecover} +can repair bit flip errors (one of the most common forms of data corruption) +in lzip files, and provides data recovery capabilities, including +error-checked merging of damaged copies of a file. +@ifnothtml +@xref{Data safety,,,lziprecover}. +@end ifnothtml + +@item +The lzip format is as simple as possible (but not simpler). The lzip +manual provides the source code of a simple decompressor along with a +detailed explanation of how it works, so that with the only help of the +lzip manual it would be possible for a digital archaeologist to extract +the data from a lzip file long after quantum computers eventually +render LZMA obsolete. + +@item +Additionally the lzip reference implementation is copylefted, which +guarantees that it will remain free forever. +@end itemize + +A nice feature of the lzip format is that a corrupt byte is easier to repair +the nearer it is from the beginning of the file. Therefore, with the help of +lziprecover, losing an entire archive just because of a corrupt byte near +the beginning is a thing of the past. + +The member trailer stores the 32-bit CRC of the original data, the size of +the original data, and the size of the member. These values, together with +the "End Of Stream" marker, provide a 3-factor integrity checking which +guarantees that the decompressed version of the data is identical to the +original. This guards against corruption of the compressed data, and against +undetected bugs in lzip (hopefully very unlikely). The chances of data +corruption going undetected are microscopic. Be aware, though, that the +check occurs upon decompression, so it can only tell you that something is +wrong. It can't help you recover the original uncompressed data. + +Lzip uses the same well-defined exit status values used by bzip2, which +makes it safer than compressors returning ambiguous warning values (like +gzip) when it is used as a back end for other programs like tar or zutils. + +Lzip automatically uses for each file the largest dictionary size that does +not exceed neither the file size nor the limit given. Keep in mind that the +decompression memory requirement is affected at compression time by the +choice of dictionary size limit. + +The amount of memory required for compression is about 1 or 2 times the +dictionary size limit (1 if input file size is less than dictionary size +limit, else 2) plus 9 times the dictionary size really used. The option +@option{-0} is special and only requires about @w{1.5 MiB} at most. The +amount of memory required for decompression is about @w{46 kB} larger +than the dictionary size really used. + +When compressing, lzip replaces every file given in the command line +with a compressed version of itself, with the name "original_name.lz". +When decompressing, lzip attempts to guess the name for the decompressed +file from that of the compressed file as follows: + +@multitable {anyothername} {becomes} {anyothername.out} +@item filename.lz @tab becomes @tab filename +@item filename.tlz @tab becomes @tab filename.tar +@item anyothername @tab becomes @tab anyothername.out +@end multitable + +(De)compressing a file is much like copying or moving it. Therefore lzip +preserves the access and modification dates, permissions, and, if you have +appropriate privileges, ownership of the file just as @w{@samp{cp -p}} does. +(If the user ID or the group ID can't be duplicated, the file permission +bits S_ISUID and S_ISGID are cleared). + +Lzip is able to read from some types of non-regular files if either the +option @option{-c} or the option @option{-o} is specified. + +Lzip refuses to read compressed data from a terminal or write compressed +data to a terminal, as this would be entirely incomprehensible and might +leave the terminal in an abnormal state. + +Lzip correctly decompresses a file which is the concatenation of two or +more compressed files. The result is the concatenation of the corresponding +decompressed files. Integrity testing of concatenated compressed files is +also supported. + +Lzip can produce multimember files, and lziprecover can safely recover the +undamaged members in case of file damage. Lzip can also split the compressed +output in volumes of a given size, even when reading from standard input. +This allows the direct creation of multivolume compressed tar archives. + +Lzip is able to compress and decompress streams of unlimited size by +automatically creating multimember output. The members so created are large, +about @w{2 PiB} each. + + +@node Output +@chapter Meaning of lzip's output +@cindex output + +The output of lzip looks like this: + +@example +lzip -v foo + foo: 6.676:1, 14.98% ratio, 85.02% saved, 450560 in, 67493 out. + +lzip -tvvv foo.lz + foo.lz: 6.676:1, 14.98% ratio, 85.02% saved. 450560 out, 67493 in. ok +@end example + +The meaning of each field is as follows: + +@table @code +@item N:1 +The compression ratio @w{(uncompressed_size / compressed_size)}, shown as +@w{N to 1}. + +@item ratio +The inverse compression ratio @w{(compressed_size / uncompressed_size)}, +shown as a percentage. A decimal ratio is easily obtained by moving the +decimal point two places to the left; @w{14.98% = 0.1498}. + +@item saved +The space saved by compression @w{(1 - ratio)}, shown as a percentage. + +@item in +Size of the input data. This is the uncompressed size when compressing, or +the compressed size when decompressing or testing. Note that lzip always +prints the uncompressed size before the compressed size when compressing, +decompressing, testing, or listing. + +@item out +Size of the output data. This is the compressed size when compressing, or +the decompressed size when decompressing or testing. + +@end table + +When decompressing or testing at verbosity level 4 (-vvvv), the dictionary +size used to compress the file and the CRC32 of the uncompressed data are +also shown. + +LANGUAGE NOTE: Uncompressed = not compressed = plain data; it may never have +been compressed. Decompressed is used to refer to data which have undergone +the process of decompression. + + +@node Invoking lzip +@chapter Invoking lzip +@cindex invoking +@cindex options +@cindex usage +@cindex version + +The format for running lzip is: + +@example +lzip [@var{options}] [@var{files}] +@end example + +@noindent +If no file names are specified, lzip compresses (or decompresses) from +standard input to standard output. A hyphen @samp{-} used as a @var{file} +argument means standard input. It can be mixed with other @var{files} and is +read just once, the first time it appears in the command line. Remember to +prepend @file{./} to any file name beginning with a hyphen, or use @samp{--}. + +lzip supports the following +@uref{http://www.nongnu.org/arg-parser/manual/arg_parser_manual.html#Argument-syntax,,options}: +@ifnothtml +@xref{Argument syntax,,,arg_parser}. +@end ifnothtml + +@table @code +@item -h +@itemx --help +Print an informative help message describing the options and exit. + +@item -V +@itemx --version +Print the version number of lzip on the standard output and exit. +This version number should be included in all bug reports. + +@anchor{--trailing-error} +@item -a +@itemx --trailing-error +Exit with error status 2 if any remaining input is detected after +decompressing the last member. Such remaining input is usually trailing +garbage that can be safely ignored. @xref{concat-example}. + +@item -b @var{bytes} +@itemx --member-size=@var{bytes} +When compressing, set the member size limit to @var{bytes}. It is advisable +to keep members smaller than RAM size so that they can be repaired with +lziprecover in case of corruption. A small member size may degrade +compression ratio, so use it only when needed. Valid values range from +@w{100 kB} to @w{2 PiB}. Defaults to @w{2 PiB}. + +@item -c +@itemx --stdout +Compress or decompress to standard output; keep input files unchanged. If +compressing several files, each file is compressed independently. (The +output consists of a sequence of independently compressed members). This +option (or @option{-o}) is needed when reading from a named pipe (fifo) or +from a device. Use it also to recover as much of the decompressed data as +possible when decompressing a corrupt file. @option{-c} overrides @option{-o} +and @option{-S}. @option{-c} has no effect when testing or listing. + +@item -d +@itemx --decompress +Decompress the files specified. The integrity of the files specified is +checked. If a file does not exist, can't be opened, or the destination file +already exists and @option{--force} has not been specified, lzip continues +decompressing the rest of the files and exits with error status 1. If a file +fails to decompress, or is a terminal, lzip exits immediately with error +status 2 without decompressing the rest of the files. A terminal is +considered an uncompressed file, and therefore invalid. + +@item -f +@itemx --force +Force overwrite of output files. + +@item -F +@itemx --recompress +When compressing, force re-compression of files whose name already has +the @samp{.lz} or @samp{.tlz} suffix. + +@item -k +@itemx --keep +Keep (don't delete) input files during compression or decompression. + +@item -l +@itemx --list +Print the uncompressed size, compressed size, and percentage saved of the +files specified. Trailing data are ignored. The values produced are correct +even for multimember files. If more than one file is given, a final line +containing the cumulative sizes is printed. With @option{-v}, the dictionary +size, the number of members in the file, and the amount of trailing data (if +any) are also printed. With @option{-vv}, the positions and sizes of each +member in multimember files are also printed. + +If any file is damaged, does not exist, can't be opened, or is not regular, +the final exit status is @w{> 0}. @option{-lq} can be used to check quickly +(without decompressing) the structural integrity of the files specified. +(Use @option{--test} to check the data integrity). @option{-alq} +additionally checks that none of the files specified contain trailing data. + +@item -m @var{bytes} +@itemx --match-length=@var{bytes} +When compressing, set the match length limit in bytes. After a match this +long is found, the search is finished. Valid values range from 5 to 273. +Larger values usually give better compression ratios but longer compression +times. + +@item -o @var{file} +@itemx --output=@var{file} +If @option{-c} has not been also specified, write the (de)compressed output +to @var{file}, automatically creating any missing parent directories; keep +input files unchanged. If compressing several files, each file is compressed +independently. (The output consists of a sequence of independently +compressed members). This option (or @option{-c}) is needed when reading +from a named pipe (fifo) or from a device. @w{@option{-o -}} is equivalent +to @option{-c}. @option{-o} has no effect when testing or listing. + +In order to keep backward compatibility with lzip versions prior to 1.22, +when compressing from standard input and no other file names are given, the +extension @samp{.lz} is appended to @var{file} unless it already ends in +@samp{.lz} or @samp{.tlz}. This feature will be removed in a future version +of lzip. Meanwhile, redirection may be used instead of @option{-o} to write +the compressed output to a file without the extension @samp{.lz} in its +name: @w{@samp{lzip < file > foo}}. + +When compressing and splitting the output in volumes, @var{file} is used as +a prefix, and several files named @samp{@var{file}00001.lz}, +@samp{@var{file}00002.lz}, etc, are created. In this case, only one input +file is allowed. + +@item -q +@itemx --quiet +Quiet operation. Suppress all messages. + +@item -s @var{bytes} +@itemx --dictionary-size=@var{bytes} +When compressing, set the dictionary size limit in bytes. Lzip uses for +each file the largest dictionary size that does not exceed neither the file +size nor this limit. Valid values range from @w{4 KiB} to @w{512 MiB}. +Values 12 to 29 are interpreted as powers of two, meaning 2^12 to 2^29 +bytes. Dictionary sizes are quantized so that they can be coded in just one +byte (@pxref{coded-dict-size}). If the size specified does not match one of +the valid sizes, it is rounded upwards by adding up to @w{(@var{bytes} / 8)} +to it. + +For maximum compression you should use a dictionary size limit as large +as possible, but keep in mind that the decompression memory requirement +is affected at compression time by the choice of dictionary size limit. + +@item -S @var{bytes} +@itemx --volume-size=@var{bytes} +When compressing, and @option{-c} has not been also specified, split the +compressed output into several volume files with names +@samp{original_name00001.lz}, @samp{original_name00002.lz}, etc, and set the +volume size limit to @var{bytes}. Input files are kept unchanged. Each +volume is a complete, maybe multimember, lzip file. A small volume size may +degrade compression ratio, so use it only when needed. Valid values range +from @w{100 kB} to @w{4 EiB}. + +@item -t +@itemx --test +Check integrity of the files specified, but don't decompress them. This +really performs a trial decompression and throws away the result. Use it +together with @option{-v} to see information about the files. If a file +fails the test, does not exist, can't be opened, or is a terminal, lzip +continues testing the rest of the files. A final diagnostic is shown at +verbosity level 1 or higher if any file fails the test when testing multiple +files. + +@item -v +@itemx --verbose +Verbose mode.@* +When compressing, show the compression ratio and size for each file +processed.@* +When decompressing or testing, further -v's (up to 4) increase the +verbosity level, showing status, compression ratio, dictionary size, +trailer contents (CRC, data size, member size), and up to 6 bytes of +trailing data (if any) both in hexadecimal and as a string of printable +ASCII characters.@* +Two or more @option{-v} options show the progress of (de)compression. + +@item -0 .. -9 +Compression level. Set the compression parameters (dictionary size and +match length limit) as shown in the table below. The default compression +level is @option{-6}, equivalent to @w{@option{-s8MiB -m36}}. Note that +@option{-9} can be much slower than @option{-0}. These options have no +effect when decompressing, testing, or listing. + +The bidimensional parameter space of LZMA can't be mapped to a linear scale +optimal for all files. If your files are large, very repetitive, etc, you +may need to use the options @option{--dictionary-size} and +@option{--match-length} directly to achieve optimal performance. + +If several compression levels or @option{-s} or @option{-m} options are +given, the last setting is used. For example @w{@option{-9 -s64MiB}} is +equivalent to @w{@option{-s64MiB -m273}} + +@multitable {Level} {Dictionary size (-s)} {Match length limit (-m)} +@item Level @tab Dictionary size (-s) @tab Match length limit (-m) +@item -0 @tab 64 KiB @tab 16 bytes +@item -1 @tab 1 MiB @tab 5 bytes +@item -2 @tab 1.5 MiB @tab 6 bytes +@item -3 @tab 2 MiB @tab 8 bytes +@item -4 @tab 3 MiB @tab 12 bytes +@item -5 @tab 4 MiB @tab 20 bytes +@item -6 @tab 8 MiB @tab 36 bytes +@item -7 @tab 16 MiB @tab 68 bytes +@item -8 @tab 24 MiB @tab 132 bytes +@item -9 @tab 32 MiB @tab 273 bytes +@end multitable + +@item --fast +@itemx --best +Aliases for GNU gzip compatibility. + +@item --empty-error +Exit with error status 2 if any empty member is found in the input files. + +@item --marking-error +Exit with error status 2 if the first LZMA byte is non-zero in any member of +the input files. This may be caused by data corruption or by deliberate +insertion of tracking information in the file. Use +@w{@samp{lziprecover --clear-marking}} to clear any such non-zero bytes. + +@item --loose-trailing +When decompressing, testing, or listing, allow trailing data whose first +bytes are so similar to the magic bytes of a lzip header that they can +be confused with a corrupt header. Use this option if a file triggers a +"corrupt header" error and the cause is not indeed a corrupt header. + +@end table + +Numbers given as arguments to options may be expressed in decimal, +hexadecimal, or octal (using the same syntax as integer constants in C++), +and may be followed by a multiplier and an optional @samp{B} for "byte". + +Table of SI and binary prefixes (unit multipliers): + +@multitable {Prefix} {kilobyte (10^3 = 1000)} {|} {Prefix} {kibibyte (2^10 = 1024)} +@item Prefix @tab Value @tab | @tab Prefix @tab Value +@item k @tab kilobyte (10^3 = 1000) @tab | @tab Ki @tab kibibyte (2^10 = 1024) +@item M @tab megabyte (10^6) @tab | @tab Mi @tab mebibyte (2^20) +@item G @tab gigabyte (10^9) @tab | @tab Gi @tab gibibyte (2^30) +@item T @tab terabyte (10^12) @tab | @tab Ti @tab tebibyte (2^40) +@item P @tab petabyte (10^15) @tab | @tab Pi @tab pebibyte (2^50) +@item E @tab exabyte (10^18) @tab | @tab Ei @tab exbibyte (2^60) +@item Z @tab zettabyte (10^21) @tab | @tab Zi @tab zebibyte (2^70) +@item Y @tab yottabyte (10^24) @tab | @tab Yi @tab yobibyte (2^80) +@item R @tab ronnabyte (10^27) @tab | @tab Ri @tab robibyte (2^90) +@item Q @tab quettabyte (10^30) @tab | @tab Qi @tab quebibyte (2^100) +@end multitable + +@sp 1 +Exit status: 0 for a normal exit, 1 for environmental problems +(file not found, invalid command-line options, I/O errors, etc), 2 to +indicate a corrupt or invalid input file, 3 for an internal consistency +error (e.g., bug) which caused lzip to panic. + + +@node Quality assurance +@chapter Design, development, and testing of lzip +@cindex quality assurance + +There are two ways of constructing a software design: One way is to make it +so simple that there are obviously no deficiencies and the other way is to +make it so complicated that there are no obvious deficiencies. The first +method is far more difficult.@* +--- C.A.R. Hoare + +Lzip has been designed, written, and tested with great care to replace gzip +and bzip2 as the standard general-purpose compressed format for Unix-like +systems. This chapter describes the lessons learned from these previous +formats, and their application to the design of lzip. The lzip format +specification has been reviewed carefully and is believed to be free from +design errors. + +@sp 1 +@section Format design + +When gzip was designed in 1992, computers and operating systems were much +less capable than they are today. The designers of gzip tried to work around +some of those limitations, like 8.3 file names, with additional fields in +the file format. + +Today those limitations have mostly disappeared, and the format of gzip has +proved to be unnecessarily complicated. It includes fields that were never +used, others that have lost their usefulness, and finally others that have +become too limited. + +Bzip2 was designed 5 years later, and its format is simpler than the one of +gzip. + +Probably the worst defect of the gzip format from the point of view of data +safety is the variable size of its header. If the byte at offset 3 (flags) +of a gzip member gets corrupted, it may become difficult to recover the +data, even if the compressed blocks are intact, because it can't be known +with certainty where the compressed blocks begin. + +By contrast, the header of a lzip member has a fixed length of 6. The LZMA +stream in a lzip member always starts at offset 6, making it trivial to +recover the data even if the whole header becomes corrupt. + +Bzip2 also provides a header of fixed length and marks the begin and end of +each compressed block with six magic bytes, making it possible to find the +compressed blocks even in case of file damage. But bzip2 does not store the +size of each compressed block, as lzip does. + +Lziprecover is able to provide unique data recovery capabilities because the +lzip format is extraordinarily safe. The simple and safe design of the file +format complements the embedded error detection provided by the LZMA data +stream. Any distance larger than the dictionary size acts as a forbidden +symbol, allowing the decompressor to detect the approximate position of +errors, and leaving very little work for the check sequence (CRC and data +sizes) in the detection of errors. Lzip is usually able to detect all +possible bit flips in the compressed data without resorting to the check +sequence. It would be difficult to write an automatic recovery tool like +lziprecover for the gzip format. And, as far as I know, it has never been +written. + +Lzip, like gzip and bzip2, uses a CRC32 to check the integrity of the +decompressed data because it provides optimal accuracy in the detection of +errors up to a compressed size of about @w{16 GiB}, a size larger than that +of most files. In the case of lzip, the additional detection capability of +the decompressor reduces the probability of undetected errors several +million times more, resulting in a combined integrity checking optimally +accurate for any member size produced by lzip. Preliminary results suggest +that the lzip format is safe enough to be used in critical safety avionics +systems. + +The lzip format is designed for long-term archiving. Therefore it excludes +any unneeded features that may interfere with the future extraction of the +decompressed data. + +@sp 1 +@subsection Gzip format (mis)features not present in lzip + +@table @samp +@item Multiple algorithms + +Gzip provides a CM (Compression Method) field that has never been used +because it is a bad idea to begin with. New compression methods may require +additional fields, making it impossible to implement new methods and, at the +same time, keep the same format. This field does not solve the problem of +format proliferation; it just makes the problem less obvious. + +@item Optional fields in header + +Unless special precautions are taken, optional fields are generally a bad +idea because they produce a header of variable size. The gzip header has 2 +fields that, in addition to being optional, are zero-terminated. This means +that if any byte inside the field gets zeroed, or if the terminating zero +gets altered, gzip won't be able to find neither the header CRC nor the +compressed blocks. + +@item Optional CRC for the header + +Using an optional CRC for the header is not only a bad idea, it is an error; +it circumvents the Hamming distance (HD) of the CRC and may prevent the +extraction of perfectly good data. For example, if the CRC is used and the +bit enabling it is reset by a bit flip, then the header seems to be intact +(in spite of being corrupt) while the compressed blocks seem to be totally +unrecoverable (in spite of being intact). Very misleading indeed. + +@item Metadata + +The gzip format stores some metadata, like the modification time of the +original file or the operating system on which compression took place. This +complicates reproducible compression (obtaining identical compressed output +from identical input). + +@end table + +@subsection Lzip format improvements over gzip and bzip2 + +@table @samp +@item 64-bit size field + +Probably the most frequently reported shortcoming of the gzip format is that +it only stores the least significant 32 bits of the uncompressed size. The +size of any file larger or equal than @w{4 GiB} gets truncated. + +Bzip2 does not store the uncompressed size of the file. + +The lzip format provides a 64-bit field for the uncompressed size. +Additionally, lzip produces multimember output automatically when the size +is too large for a single member, allowing for an unlimited uncompressed +size. + +@item Distributed index + +The lzip format provides a distributed index that, among other things, helps +plzip to decompress several times faster than pigz and helps lziprecover do +its job. Neither the gzip format nor the bzip2 format do provide an index. + +A distributed index is safer and more scalable than a monolithic index. The +monolithic index introduces a single point of failure in the compressed file +and may limit the number of members or the total uncompressed size. + +@end table + +@section Quality of implementation + +Our civilization depends critically on software; it had better be quality +software.@* +--- Bjarne Stroustrup + +@table @samp +@item Accurate and robust error detection + +The lzip format provides 3-factor integrity checking, and the decompressors +report mismatches in each factor separately. This method detects most false +positives for corruption. If just one byte in one factor fails but the other +two factors match the data, it probably means that the data are intact and +the corruption just affects the mismatching factor (CRC, data size, or +member size) in the member trailer. + +@item Multiple implementations + +Just like the lzip format provides 3-factor protection against undetected +data corruption, the development methodology of the lzip family of +compressors provides 3-factor protection against undetected programming +errors. + +Three related but independent compressor implementations, lzip, clzip, and +minilzip/lzlib, are developed concurrently. Every stable release of any of +them is tested to check that it produces identical output to the other two. +This guarantees that all three implement the same algorithm, and makes it +unlikely that any of them may contain serious undiscovered errors. In fact, +no errors have been discovered in lzip since 2009. + +Additionally, the three implementations have been extensively tested with +@uref{http://www.nongnu.org/lzip/manual/lziprecover_manual.html#Unzcrash,,unzcrash}, +valgrind, and @samp{american fuzzy lop} without finding a single +vulnerability or false negative. +@ifnothtml +@xref{Unzcrash,,,lziprecover}. +@end ifnothtml + +@item Dictionary size + +Lzip automatically adapts the dictionary size to the size of each file. +In addition to reducing the amount of memory required for decompression, +this feature also minimizes the probability of being affected by RAM errors +during compression. @c key4_mask + +@item Exit status + +Returning a warning status of 2 is a design flaw of compress that leaked +into the design of gzip. Both bzip2 and lzip are free from this flaw. + +@end table + + +@node Algorithm +@chapter Algorithm +@cindex algorithm + +In spite of its name (Lempel-Ziv-Markov chain-Algorithm), LZMA is not a +concrete algorithm; it is more like "any algorithm using the LZMA coding +scheme". LZMA compression consists in describing the uncompressed data as a +succession of coding sequences from the set shown in Section @samp{What is +coded} (@pxref{what-is-coded}), and then encoding them using a range +encoder. For example, the option @option{-0} of lzip uses the scheme in almost +the simplest way possible; issuing the longest match it can find, or a +literal byte if it can't find a match. Inversely, a much more elaborated way +of finding coding sequences of minimum size than the one currently used by +lzip could be developed, and the resulting sequence could also be coded +using the LZMA coding scheme. + +Lzip currently implements two variants of the LZMA algorithm: fast +(used by option @option{-0}) and normal (used by all other compression levels). + +The high compression of LZMA comes from combining two basic, well-proven +compression ideas: sliding dictionaries (LZ77) and Markov models (the thing +used by every compression algorithm that uses a range encoder or similar +order-0 entropy coder as its last stage) with segregation of contexts +according to what the bits are used for. + +Lzip is a two stage compressor. The first stage is a Lempel-Ziv coder, +which reduces redundancy by translating chunks of data to their +corresponding distance-length pairs. The second stage is a range encoder +that uses a different probability model for each type of data: +distances, lengths, literal bytes, etc. + +Here is how it works, step by step: + +1) The member header is written to the output stream. + +2) The first byte is coded literally, because there are no previous +bytes to which the match finder can refer to. + +3) The main encoder advances to the next byte in the input data and +calls the match finder. + +4) The match finder fills an array with the minimum distances before the +current byte where a match of a given length can be found. + +5) Go back to step 3 until a sequence (formed of pairs, repeated +distances, and literal bytes) of minimum price has been formed. Where the +price represents the number of output bits produced. + +6) The range encoder encodes the sequence produced by the main encoder +and sends the bytes produced to the output stream. + +7) Go back to step 3 until the input data are finished or until the +member or volume size limits are reached. + +8) The range encoder is flushed. + +9) The member trailer is written to the output stream. + +10) If there are more data to compress, go back to step 1. + +@sp 1 +During compression, lzip reads data in large blocks (one dictionary size at +a time). Therefore it may block for up to tens of seconds any process +feeding data to it through a pipe. This is normal. The blocking intervals +get longer with higher compression levels because dictionary size increases +(and compression speed decreases) with compression level. + +@noindent +The ideas embodied in lzip are due to (at least) the following people: +Abraham Lempel and Jacob Ziv (for the LZ algorithm), Andrei Markov (for the +definition of Markov chains), G.N.N. Martin (for the definition of range +encoding), Igor Pavlov (for putting all the above together in LZMA), and +Julian Seward (for bzip2's CLI). + + +@node File format +@chapter File format +@cindex file format + +Perfection is reached, not when there is no longer anything to add, but +when there is no longer anything to take away.@* +--- Antoine de Saint-Exupery + +@sp 1 +In the diagram below, a box like this: + +@verbatim ++---+ +| | <-- the vertical bars might be missing ++---+ +@end verbatim + +represents one byte; a box like this: + +@verbatim ++==============+ +| | ++==============+ +@end verbatim + +represents a variable number of bytes. + +@sp 1 +A lzip file consists of one or more independent "members" (compressed data +sets). The members simply appear one after another in the file, with no +additional information before, between, or after them. Each member can +encode in compressed form up to @w{16 EiB - 1 byte} of uncompressed data. +The size of a multimember file is unlimited. + +Each member has the following structure: + +@verbatim ++--+--+--+--+----+----+=============+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +| ID string | VN | DS | LZMA stream | CRC32 | Data size | Member size | ++--+--+--+--+----+----+=============+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +@end verbatim + +All multibyte values are stored in little endian order. + +@table @samp +@item ID string (the "magic" bytes) +A four byte string, identifying the lzip format, with the value "LZIP" +(0x4C, 0x5A, 0x49, 0x50). + +@item VN (version number, 1 byte) +Just in case something needs to be modified in the future. 1 for now. + +@anchor{coded-dict-size} +@item DS (coded dictionary size, 1 byte) +The dictionary size is calculated by taking a power of 2 (the base size) +and subtracting from it a fraction between 0/16 and 7/16 of the base size.@* +Bits 4-0 contain the base 2 logarithm of the base size (12 to 29).@* +Bits 7-5 contain the numerator of the fraction (0 to 7) to subtract +from the base size to obtain the dictionary size.@* +Example: 0xD3 = 2^19 - 6 * 2^15 = 512 KiB - 6 * 32 KiB = 320 KiB@* +Valid values for dictionary size range from 4 KiB to 512 MiB. + +@item LZMA stream +The LZMA stream, finished by an "End Of Stream" marker. Uses default values +for encoder properties. @xref{Stream format}, for a complete description. + +@item CRC32 (4 bytes) +Cyclic Redundancy Check (CRC) of the original uncompressed data. + +@item Data size (8 bytes) +Size of the original uncompressed data. + +@item Member size (8 bytes) +Total size of the member, including header and trailer. This field acts +as a distributed index, improves the checking of stream integrity, and +facilitates the safe recovery of undamaged members from multimember files. +Lzip limits the member size to @w{2 PiB} to prevent the data size field from +overflowing. + +@end table + + +@node Stream format +@chapter Format of the LZMA stream in lzip files +@cindex format of the LZMA stream + +The LZMA algorithm has three parameters, called "special LZMA +properties", to adjust it for some kinds of binary data. These +parameters are: @samp{literal_context_bits} (with a default value of 3), +@samp{literal_pos_state_bits} (with a default value of 0), and +@samp{pos_state_bits} (with a default value of 2). As a general purpose +compressor, lzip only uses the default values for these parameters. In +particular @samp{literal_pos_state_bits} has been optimized away and +does not even appear in the code. + +Lzip finishes the LZMA stream with an "End Of Stream" (EOS) marker (the +distance-length pair @w{0xFFFFFFFFU, 2}), which in conjunction with the +@samp{member size} field in the member trailer allows the checking of stream +integrity. The EOS marker is the only LZMA marker allowed in lzip files. The +LZMA stream in lzip files always has these two features (default properties +and EOS marker) and is referred to in this document as LZMA-302eos. This +simplified and marker-terminated form of the LZMA stream format has been +chosen to maximize interoperability and safety. + +The second stage of LZMA is a range encoder that uses a different +probability model for each type of symbol: distances, lengths, literal +bytes, etc. Range encoding conceptually encodes all the symbols of the +message into one number. Unlike Huffman coding, which assigns to each +symbol a bit-pattern and concatenates all the bit-patterns together, +range encoding can compress one symbol to less than one bit. Therefore +the compressed data produced by a range encoder can't be split in pieces +that could be described individually. + +It seems that the only way of describing the LZMA-302eos stream is to +describe the algorithm that decodes it. And given the many details +about the range decoder that need to be described accurately, the source +code of a real decompressor seems the only appropriate reference to use. + +What follows is a description of the decoding algorithm for LZMA-302eos +streams using as reference the source code of "lzd", an educational +decompressor for lzip files, included in appendix A. @xref{Reference source +code}. Lzd is written in C++11 and can be downloaded from the lzip download +directory. + +@sp 1 +@section What is coded + +@anchor{what-is-coded} +The LZMA stream includes literals, matches, and repeated matches (matches +reusing a recently used distance). There are 7 different coding sequences: + +@multitable @columnfractions .35 .14 .51 +@headitem Bit sequence @tab Name @tab Description +@item 0 + byte @tab literal @tab literal byte +@item 1 + 0 + len + dis @tab match @tab distance-length pair +@item 1 + 1 + 0 + 0 @tab shortrep @tab 1 byte match at latest used distance +@item 1 + 1 + 0 + 1 + len @tab rep0 @tab len bytes match at latest used distance +@item 1 + 1 + 1 + 0 + len @tab rep1 @tab len bytes match at second +latest used distance +@item 1 + 1 + 1 + 1 + 0 + len @tab rep2 @tab len bytes match at third +latest used distance +@item 1 + 1 + 1 + 1 + 1 + len @tab rep3 @tab len bytes match at fourth +latest used distance +@end multitable + +@sp 1 +In the following tables, multibit sequences are coded in normal order, +from most significant bit (MSB) to least significant bit (LSB), except +where noted otherwise. + +Lengths (the @samp{len} in the table above) are coded as follows: + +@multitable @columnfractions .5 .5 +@headitem Bit sequence @tab Description +@item 0 + 3 bits @tab lengths from 2 to 9 +@item 1 + 0 + 3 bits @tab lengths from 10 to 17 +@item 1 + 1 + 8 bits @tab lengths from 18 to 273 +@end multitable + +@sp 1 +The coding of distances is a little more complicated, so I'll begin by +explaining a simpler version of the encoding. + +Imagine you need to encode a number from 0 to @w{2^32 - 1}, and you want to +do it in a way that produces shorter codes for the smaller numbers. You may +first encode the position of the most significant bit that is set to 1, +which you may find by making a bit scan from the left (from the MSB). A +position of 0 means that the number is 0 (no bit is set), 1 means the LSB is +the first bit set (the number is 1), and 32 means the MSB is set (i.e., the +number is @w{>= 0x80000000}). Then, if the position is @w{>= 2}, you encode +the remaining @w{position - 1} bits. Let's call these bits "direct bits" +because they are coded directly by value instead of indirectly by position. + +The inconvenient of this simple method is that it needs 6 bits to encode the +position, but it just uses 33 of the 64 possible values, wasting almost half +of the codes. + +The intelligent trick of LZMA is that it encodes in what it calls a "slot" +the position of the most significant bit set, along with the value of the +next bit, using the same 6 bits that would take to encode the position +alone. This seems to need 66 slots (twice the number of positions), but for +positions 0 and 1 there is no next bit, so the number of slots needed is 64 +(0 to 63). + +The 6 bits representing this "slot number" are then context-coded. If +the distance is @w{>= 4}, the remaining bits are encoded as follows. +@samp{direct_bits} is the amount of remaining bits (from 1 to 30) needed +to form a complete distance, and is calculated as @w{(slot >> 1) - 1}. +If a distance needs 6 or more direct_bits, the last 4 bits are encoded +separately. The last piece (all the direct_bits for distances 4 to 127 +(slots 4 to 13), or the last 4 bits for distances @w{>= 128} +@w{(slot >= 14)}) is context-coded in reverse order (from LSB to MSB). For +distances @w{>= 128}, the @w{@samp{direct_bits - 4}} part is encoded with +fixed 0.5 probability. + +@multitable @columnfractions .5 .5 +@headitem Bit sequence @tab Description +@item slot @tab distances from 0 to 3 +@item slot + direct_bits @tab distances from 4 to 127 +@item slot + (direct_bits - 4) + 4 bits @tab distances from 128 to 2^32 - 1 +@end multitable + +@sp 1 +@section The coding contexts + +These contexts (@samp{Bit_model} in the source), are integers or arrays +of integers representing the probability of the corresponding bit being 0. + +The indices used in these arrays are: + +@table @samp +@item state +A state machine (@samp{State} in the source) with 12 states (0 to 11), +coding the latest 2 to 4 types of sequences processed. The initial state +is 0. + +@item pos_state +Value of the 2 least significant bits of the current position in the +decoded data. + +@item literal_state +Value of the 3 most significant bits of the latest byte decoded. + +@item len_state +Coded value of the current match length @w{(length - 2)}, with a maximum +of 3. The resulting value is in the range 0 to 3. + +@end table + + +The types of previous sequences corresponding to each state are shown in the +following table. @samp{!literal} is any sequence except a literal byte. +@samp{rep} is any one of @samp{rep0}, @samp{rep1}, @samp{rep2}, or +@samp{rep3}. The last type in each line is the most recent. + +@multitable {State} {rep or (!literal, shortrep), literal, literal} +@headitem State @tab Types of previous sequences +@item 0 @tab literal, literal, literal +@item 1 @tab match, literal, literal +@item 2 @tab rep or (!literal, shortrep), literal, literal +@item 3 @tab literal, shortrep, literal, literal +@item 4 @tab match, literal +@item 5 @tab rep or (!literal, shortrep), literal +@item 6 @tab literal, shortrep, literal +@item 7 @tab literal, match +@item 8 @tab literal, rep +@item 9 @tab literal, shortrep +@item 10 @tab !literal, match +@item 11 @tab !literal, (rep or shortrep) +@end multitable + +@sp 1 +The contexts for decoding the type of coding sequence are: + +@multitable @columnfractions .2 .35 .45 +@headitem Name @tab Indices @tab Used when +@item bm_match @tab state, pos_state @tab sequence start +@item bm_rep @tab state @tab after sequence 1 +@item bm_rep0 @tab state @tab after sequence 11 +@item bm_rep1 @tab state @tab after sequence 111 +@item bm_rep2 @tab state @tab after sequence 1111 +@item bm_len @tab state, pos_state @tab after sequence 110 +@end multitable + +@sp 1 +The contexts for decoding distances are: + +@multitable @columnfractions .2 .3 .5 +@headitem Name @tab Indices @tab Used when +@item bm_dis_slot @tab len_state, bit tree @tab distance start +@item bm_dis @tab reverse bit tree @tab after slots 4 to 13 +@item bm_align @tab reverse bit tree @tab for distances >= 128, after +fixed probability bits +@end multitable + +@sp 1 +There are two separate sets of contexts for lengths (@samp{Len_model} in +the source). One for normal matches, the other for repeated matches. The +contexts in each Len_model are (see @samp{decode_len} in the source): + +@multitable @columnfractions .2 .4 .4 +@headitem Name @tab Indices @tab Used when +@item choice1 @tab none @tab length start +@item choice2 @tab none @tab after sequence 1 +@item bm_low @tab pos_state, bit tree @tab after sequence 0 +@item bm_mid @tab pos_state, bit tree @tab after sequence 10 +@item bm_high @tab bit tree @tab after sequence 11 +@end multitable + +@sp 1 +The context array @samp{bm_literal} is special. In principle it acts as +a normal bit tree context, the one selected by @samp{literal_state}. But +if the previous decoded byte was not a literal, two other bit tree +contexts are used depending on the value of each bit in +@samp{match_byte} (the byte at the latest used distance), until a bit is +decoded that is different from its corresponding bit in +@samp{match_byte}. After the first difference is found, the rest of the +byte is decoded using the normal bit tree context. (See +@samp{decode_matched} in the source). + +@sp 1 +@section The range decoder + +The LZMA stream is consumed one byte at a time by the range decoder. +(See @samp{normalize} in the source). Every byte consumed produces a +variable number of decoded bits, depending on how well these bits agree +with their context. (See @samp{decode_bit} in the source). + +The range decoder state consists of two unsigned 32-bit variables: +@samp{range} (representing the most significant part of the range size +not yet decoded) and @samp{code} (representing the current point within +@samp{range}). @samp{range} is initialized to @w{2^32 - 1}, and +@samp{code} is initialized to 0. + +The range encoder produces a first 0 byte that must be ignored by the +range decoder. (See the @samp{Range_decoder} constructor in the source). + +@sp 1 +@section Decoding and checking the LZMA stream + +After decoding the member header and obtaining the dictionary size, the +range decoder is initialized and then the LZMA decoder enters a loop +(see @samp{decode_member} in the source) where it invokes the range +decoder with the appropriate contexts to decode the different coding +sequences (matches, repeated matches, and literal bytes), until the "End +Of Stream" marker is decoded. + +Once the "End Of Stream" marker has been decoded, the decompressor reads and +decodes the member trailer, and checks that the three integrity factors +stored there (CRC, data size, and member size) match those computed from the +data. + + +@node Trailing data +@chapter Extra data appended to the file +@cindex trailing data + +Sometimes extra data are found appended to a lzip file after the last +member. Such trailing data may be: + +@itemize @bullet +@item +Padding added to make the file size a multiple of some block size, for +example when writing to a tape. It is safe to append any amount of +padding zero bytes to a lzip file. + +@item +Useful data added by the user; an "End Of File" string (to check that the +file has not been truncated), a cryptographically secure hash, a description +of file contents, etc. It is safe to append any amount of text to a lzip +file as long as none of the first four bytes of the text matches the +corresponding byte in the string "LZIP", and the text does not contain any +zero bytes (null characters). Nonzero bytes and zero bytes can't be safely +mixed in trailing data. + +@item +Garbage added by some not totally successful copy operation. + +@item +Malicious data added to the file in order to make its total size and +hash value (for a chosen hash) coincide with those of another file. + +@item +In rare cases, trailing data could be the corrupt header of another +member. In multimember or concatenated files the probability of +corruption happening in the magic bytes is 5 times smaller than the +probability of getting a false positive caused by the corruption of the +integrity information itself. Therefore it can be considered to be below +the noise level. Additionally, the test used by lzip to discriminate +trailing data from a corrupt header has a Hamming distance (HD) of 3, +and the 3 bit flips must happen in different magic bytes for the test to +fail. In any case, the option @option{--trailing-error} guarantees that +any corrupt header is detected. +@end itemize + +Trailing data are in no way part of the lzip file format, but tools +reading lzip files are expected to behave as correctly and usefully as +possible in the presence of trailing data. + +Trailing data can be safely ignored in most cases. In some cases, like +that of user-added data, they are expected to be ignored. In those cases +where a file containing trailing data must be rejected, the option +@option{--trailing-error} can be used. @xref{--trailing-error}. + + +@node Examples +@chapter A small tutorial with examples +@cindex examples + +WARNING! Even if lzip is bug-free, other causes may result in a corrupt +compressed file (bugs in the system libraries, memory errors, etc). +Therefore, if the data you are going to compress are important, give the +option @option{--keep} to lzip and don't remove the original file until you +check the compressed file with a command like +@w{@samp{lzip -cd file.lz | cmp file -}}. Most RAM errors happening during +compression can only be detected by comparing the compressed file with the +original because the corruption happens before lzip compresses the RAM +contents, resulting in a valid compressed file containing wrong data. + +@sp 1 +@noindent +Example 1: Extract all the files from archive @samp{foo.tar.lz}. + +@example + tar -xf foo.tar.lz +or + lzip -cd foo.tar.lz | tar -xf - +@end example + +@sp 1 +@noindent +Example 2: Replace a regular file with its compressed version @samp{file.lz} +and show the compression ratio. + +@example +lzip -v file +@end example + +@sp 1 +@noindent +Example 3: Like example 2 but the created @samp{file.lz} is multimember with +a member size of @w{1 MiB}. The compression ratio is not shown. + +@example +lzip -b 1MiB file +@end example + +@sp 1 +@noindent +Example 4: Restore a regular file from its compressed version +@samp{file.lz}. If the operation is successful, @samp{file.lz} is removed. + +@example +lzip -d file.lz +@end example + +@sp 1 +@noindent +Example 5: Check the integrity of the compressed file @samp{file.lz} and +show status. + +@example +lzip -tv file.lz +@end example + +@sp 1 +@anchor{concat-example} +@noindent +Example 6: The right way of concatenating the decompressed output of two or +more compressed files. @xref{Trailing data}. + +@example +Don't do this + cat file1.lz file2.lz file3.lz | lzip -d - +Do this instead + lzip -cd file1.lz file2.lz file3.lz +@end example + +@sp 1 +@noindent +Example 7: Decompress @samp{file.lz} partially until @w{10 KiB} of +decompressed data are produced. + +@example +lzip -cd file.lz | dd bs=1024 count=10 +@end example + +@sp 1 +@noindent +Example 8: Decompress @samp{file.lz} partially from decompressed byte at +offset 10000 to decompressed byte at offset 14999 (5000 bytes are produced). + +@example +lzip -cd file.lz | dd bs=1000 skip=10 count=5 +@end example + +@sp 1 +@noindent +Example 9: Compress a whole device in /dev/sdc and send the output to +@samp{file.lz}. + +@example + lzip -c /dev/sdc > file.lz +or + lzip /dev/sdc -o file.lz +@end example + +@sp 1 +@noindent +Example 10: Create a multivolume compressed tar archive with a volume size +of @w{1440 KiB}. + +@example +tar -c some_directory | lzip -S 1440KiB -o volume_name - +@end example + +@sp 1 +@noindent +Example 11: Extract a multivolume compressed tar archive. + +@example +lzip -cd volume_name*.lz | tar -xf - +@end example + +@sp 1 +@noindent +Example 12: Create a multivolume compressed backup of a large database file +with a volume size of @w{650 MB}, where each volume is a multimember file +with a member size of @w{32 MiB}. + +@example +lzip -b 32MiB -S 650MB big_db +@end example + + +@node Problems +@chapter Reporting bugs +@cindex bugs +@cindex getting help + +There are probably bugs in lzip. There are certainly errors and +omissions in this manual. If you report them, they will get fixed. If +you don't, no one will ever know about them and they will remain unfixed +for all eternity, if not longer. + +If you find a bug in lzip, please send electronic mail to +@email{lzip-bug@@nongnu.org}. Include the version number, which you can +find by running @w{@samp{lzip --version}}. + + +@node Reference source code +@appendix Reference source code +@cindex reference source code + +@verbatim +/* Lzd - Educational decompressor for the lzip format + Copyright (C) 2013-2024 Antonio Diaz Diaz. + + This program is free software. Redistribution and use in source and + binary forms, with or without modification, are permitted provided + that the following conditions are met: + + 1. Redistributions of source code must retain the above copyright + notice, this list of conditions, and the following disclaimer. + + 2. Redistributions in binary form must reproduce the above copyright + notice, this list of conditions, and the following disclaimer in the + documentation and/or other materials provided with the distribution. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. +*/ +/* + Exit status: 0 for a normal exit, 1 for environmental problems + (file not found, invalid command-line options, I/O errors, etc), 2 to + indicate a corrupt or invalid input file. +*/ + +#include +#include +#include +#include +#include +#include +#include +#if defined __MSVCRT__ || defined __OS2__ || defined __DJGPP__ +#include +#include +#endif + + +class State + { + int st; + +public: + enum { states = 12 }; + State() : st( 0 ) {} + int operator()() const { return st; } + bool is_char() const { return st < 7; } + + void set_char() + { + const int next[states] = { 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 4, 5 }; + st = next[st]; + } + void set_match() { st = ( st < 7 ) ? 7 : 10; } + void set_rep() { st = ( st < 7 ) ? 8 : 11; } + void set_short_rep() { st = ( st < 7 ) ? 9 : 11; } + }; + + +enum { + min_dictionary_size = 1 << 12, + max_dictionary_size = 1 << 29, + literal_context_bits = 3, + literal_pos_state_bits = 0, // not used + pos_state_bits = 2, + pos_states = 1 << pos_state_bits, + pos_state_mask = pos_states - 1, + + len_states = 4, + dis_slot_bits = 6, + start_dis_model = 4, + end_dis_model = 14, + modeled_distances = 1 << ( end_dis_model / 2 ), // 128 + dis_align_bits = 4, + dis_align_size = 1 << dis_align_bits, + + len_low_bits = 3, + len_mid_bits = 3, + len_high_bits = 8, + len_low_symbols = 1 << len_low_bits, + len_mid_symbols = 1 << len_mid_bits, + len_high_symbols = 1 << len_high_bits, + max_len_symbols = len_low_symbols + len_mid_symbols + len_high_symbols, + + min_match_len = 2, // must be 2 + + bit_model_move_bits = 5, + bit_model_total_bits = 11, + bit_model_total = 1 << bit_model_total_bits }; + +struct Bit_model + { + int probability; + Bit_model() : probability( bit_model_total / 2 ) {} + }; + +struct Len_model + { + Bit_model choice1; + Bit_model choice2; + Bit_model bm_low[pos_states][len_low_symbols]; + Bit_model bm_mid[pos_states][len_mid_symbols]; + Bit_model bm_high[len_high_symbols]; + }; + + +class CRC32 + { + uint32_t data[256]; // Table of CRCs of all 8-bit messages. + +public: + CRC32() + { + for( unsigned n = 0; n < 256; ++n ) + { + unsigned c = n; + for( int k = 0; k < 8; ++k ) + { if( c & 1 ) c = 0xEDB88320U ^ ( c >> 1 ); else c >>= 1; } + data[n] = c; + } + } + + void update_buf( uint32_t & crc, const uint8_t * const buffer, + const int size ) const + { + for( int i = 0; i < size; ++i ) + crc = data[(crc^buffer[i])&0xFF] ^ ( crc >> 8 ); + } + }; + +const CRC32 crc32; + + +enum { header_size = 6, trailer_size = 20 }; +typedef uint8_t Lzip_header[header_size]; // 0-3 magic bytes + // 4 version + // 5 coded dictionary size +typedef uint8_t Lzip_trailer[trailer_size]; + // 0-3 CRC32 of the uncompressed data + // 4-11 size of the uncompressed data + // 12-19 member size including header and trailer + +class Range_decoder + { + unsigned long long member_pos; + uint32_t code; + uint32_t range; + +public: + Range_decoder() + : member_pos( header_size ), code( 0 ), range( 0xFFFFFFFFU ) + { + get_byte(); // discard first byte of the LZMA stream + for( int i = 0; i < 4; ++i ) code = ( code << 8 ) | get_byte(); + } + + uint8_t get_byte() { ++member_pos; return std::getc( stdin ); } + unsigned long long member_position() const { return member_pos; } + + unsigned decode( const int num_bits ) + { + unsigned symbol = 0; + for( int i = num_bits; i > 0; --i ) + { + range >>= 1; + symbol <<= 1; + if( code >= range ) { code -= range; symbol |= 1; } + if( range <= 0x00FFFFFFU ) // normalize + { range <<= 8; code = ( code << 8 ) | get_byte(); } + } + return symbol; + } + + bool decode_bit( Bit_model & bm ) + { + bool symbol; + const uint32_t bound = ( range >> bit_model_total_bits ) * bm.probability; + if( code < bound ) + { + range = bound; + bm.probability += + ( bit_model_total - bm.probability ) >> bit_model_move_bits; + symbol = 0; + } + else + { + code -= bound; + range -= bound; + bm.probability -= bm.probability >> bit_model_move_bits; + symbol = 1; + } + if( range <= 0x00FFFFFFU ) // normalize + { range <<= 8; code = ( code << 8 ) | get_byte(); } + return symbol; + } + + unsigned decode_tree( Bit_model bm[], const int num_bits ) + { + unsigned symbol = 1; + for( int i = 0; i < num_bits; ++i ) + symbol = ( symbol << 1 ) | decode_bit( bm[symbol] ); + return symbol - ( 1 << num_bits ); + } + + unsigned decode_tree_reversed( Bit_model bm[], const int num_bits ) + { + unsigned symbol = decode_tree( bm, num_bits ); + unsigned reversed_symbol = 0; + for( int i = 0; i < num_bits; ++i ) + { + reversed_symbol = ( reversed_symbol << 1 ) | ( symbol & 1 ); + symbol >>= 1; + } + return reversed_symbol; + } + + unsigned decode_matched( Bit_model bm[], const unsigned match_byte ) + { + unsigned symbol = 1; + for( int i = 7; i >= 0; --i ) + { + const bool match_bit = ( match_byte >> i ) & 1; + const bool bit = decode_bit( bm[symbol+(match_bit<<8)+0x100] ); + symbol = ( symbol << 1 ) | bit; + if( match_bit != bit ) + { + while( symbol < 0x100 ) + symbol = ( symbol << 1 ) | decode_bit( bm[symbol] ); + break; + } + } + return symbol & 0xFF; + } + + unsigned decode_len( Len_model & lm, const int pos_state ) + { + if( decode_bit( lm.choice1 ) == 0 ) + return min_match_len + + decode_tree( lm.bm_low[pos_state], len_low_bits ); + if( decode_bit( lm.choice2 ) == 0 ) + return min_match_len + len_low_symbols + + decode_tree( lm.bm_mid[pos_state], len_mid_bits ); + return min_match_len + len_low_symbols + len_mid_symbols + + decode_tree( lm.bm_high, len_high_bits ); + } + }; + + +class LZ_decoder + { + unsigned long long partial_data_pos; + Range_decoder rdec; + const unsigned dictionary_size; + uint8_t * const buffer; // output buffer + unsigned pos; // current pos in buffer + unsigned stream_pos; // first byte not yet written to stdout + uint32_t crc_; + bool pos_wrapped; + + void flush_data(); + + uint8_t peek( const unsigned distance ) const + { + if( pos > distance ) return buffer[pos - distance - 1]; + if( pos_wrapped ) return buffer[dictionary_size + pos - distance - 1]; + return 0; // prev_byte of first byte + } + + void put_byte( const uint8_t b ) + { + buffer[pos] = b; + if( ++pos >= dictionary_size ) flush_data(); + } + +public: + explicit LZ_decoder( const unsigned dict_size ) + : + partial_data_pos( 0 ), + dictionary_size( dict_size ), + buffer( new uint8_t[dictionary_size] ), + pos( 0 ), + stream_pos( 0 ), + crc_( 0xFFFFFFFFU ), + pos_wrapped( false ) + {} + + ~LZ_decoder() { delete[] buffer; } + + unsigned crc() const { return crc_ ^ 0xFFFFFFFFU; } + unsigned long long data_position() const + { return partial_data_pos + pos; } + uint8_t get_byte() { return rdec.get_byte(); } + unsigned long long member_position() const + { return rdec.member_position(); } + + bool decode_member(); + }; + + +void LZ_decoder::flush_data() + { + if( pos > stream_pos ) + { + const unsigned size = pos - stream_pos; + crc32.update_buf( crc_, buffer + stream_pos, size ); + if( std::fwrite( buffer + stream_pos, 1, size, stdout ) != size ) + { std::fprintf( stderr, "Write error: %s\n", std::strerror( errno ) ); + std::exit( 1 ); } + if( pos >= dictionary_size ) + { partial_data_pos += pos; pos = 0; pos_wrapped = true; } + stream_pos = pos; + } + } + + +bool LZ_decoder::decode_member() // Return false if error + { + Bit_model bm_literal[1<> ( 8 - literal_context_bits ); + Bit_model * const bm = bm_literal[literal_state]; + if( state.is_char() ) + put_byte( rdec.decode_tree( bm, 8 ) ); + else + put_byte( rdec.decode_matched( bm, peek( rep0 ) ) ); + state.set_char(); + continue; + } + // match or repeated match + int len; + if( rdec.decode_bit( bm_rep[state()] ) != 0 ) // 2nd bit + { + if( rdec.decode_bit( bm_rep0[state()] ) == 0 ) // 3rd bit + { + if( rdec.decode_bit( bm_len[state()][pos_state] ) == 0 ) // 4th bit + { state.set_short_rep(); put_byte( peek( rep0 ) ); continue; } + } + else + { + unsigned distance; + if( rdec.decode_bit( bm_rep1[state()] ) == 0 ) // 4th bit + distance = rep1; + else + { + if( rdec.decode_bit( bm_rep2[state()] ) == 0 ) // 5th bit + distance = rep2; + else + { distance = rep3; rep3 = rep2; } + rep2 = rep1; + } + rep1 = rep0; + rep0 = distance; + } + state.set_rep(); + len = rdec.decode_len( rep_len_model, pos_state ); + } + else // match + { + rep3 = rep2; rep2 = rep1; rep1 = rep0; + len = rdec.decode_len( match_len_model, pos_state ); + const int len_state = std::min( len - min_match_len, len_states - 1 ); + rep0 = rdec.decode_tree( bm_dis_slot[len_state], dis_slot_bits ); + if( rep0 >= start_dis_model ) + { + const unsigned dis_slot = rep0; + const int direct_bits = ( dis_slot >> 1 ) - 1; + rep0 = ( 2 | ( dis_slot & 1 ) ) << direct_bits; + if( dis_slot < end_dis_model ) + rep0 += rdec.decode_tree_reversed( bm_dis + ( rep0 - dis_slot ), + direct_bits ); + else + { + rep0 += + rdec.decode( direct_bits - dis_align_bits ) << dis_align_bits; + rep0 += rdec.decode_tree_reversed( bm_align, dis_align_bits ); + if( rep0 == 0xFFFFFFFFU ) // marker found + { + flush_data(); + return len == min_match_len; // End Of Stream marker + } + } + } + state.set_match(); + if( rep0 >= dictionary_size || ( rep0 >= pos && !pos_wrapped ) ) + { flush_data(); return false; } + } + for( int i = 0; i < len; ++i ) put_byte( peek( rep0 ) ); + } + flush_data(); + return false; + } + + +int main( const int argc, const char * const argv[] ) + { + if( argc > 2 || ( argc == 2 && std::strcmp( argv[1], "-d" ) != 0 ) ) + { + std::printf( + "Lzd %s - Educational decompressor for the lzip format.\n" + "Study the source code to learn how a lzip decompressor works.\n" + "See the lzip manual for an explanation of the code.\n" + "\nUsage: %s [-d] < file.lz > file\n" + "Lzd decompresses from standard input to standard output.\n" + "\nCopyright (C) 2024 Antonio Diaz Diaz.\n" + "License 2-clause BSD.\n" + "This is free software: you are free to change and redistribute it.\n" + "There is NO WARRANTY, to the extent permitted by law.\n" + "Report bugs to lzip-bug@nongnu.org\n" + "Lzd home page: http://www.nongnu.org/lzip/lzd.html\n", + PROGVERSION, argv[0] ); + return 0; + } + +#if defined __MSVCRT__ || defined __OS2__ || defined __DJGPP__ + setmode( STDIN_FILENO, O_BINARY ); + setmode( STDOUT_FILENO, O_BINARY ); +#endif + + for( bool first_member = true; ; first_member = false ) + { + Lzip_header header; // check header + for( int i = 0; i < header_size; ++i ) header[i] = std::getc( stdin ); + if( std::feof( stdin ) || std::memcmp( header, "LZIP\x01", 5 ) != 0 ) + { + if( first_member ) + { std::fputs( "Bad magic number (file not in lzip format).\n", + stderr ); return 2; } + break; // ignore trailing data + } + unsigned dict_size = 1 << ( header[5] & 0x1F ); + dict_size -= ( dict_size / 16 ) * ( ( header[5] >> 5 ) & 7 ); + if( dict_size < min_dictionary_size || dict_size > max_dictionary_size ) + { std::fputs( "Invalid dictionary size in member header.\n", stderr ); + return 2; } + + LZ_decoder decoder( dict_size ); // decode LZMA stream + if( !decoder.decode_member() ) + { std::fputs( "Data error\n", stderr ); return 2; } + + Lzip_trailer trailer; // check trailer + for( int i = 0; i < trailer_size; ++i ) trailer[i] = decoder.get_byte(); + int retval = 0; + unsigned crc = 0; + for( int i = 3; i >= 0; --i ) crc = ( crc << 8 ) + trailer[i]; + if( crc != decoder.crc() ) + { std::fputs( "CRC mismatch\n", stderr ); retval = 2; } + + unsigned long long data_size = 0; + for( int i = 11; i >= 4; --i ) + data_size = ( data_size << 8 ) + trailer[i]; + if( data_size != decoder.data_position() ) + { std::fputs( "Data size mismatch\n", stderr ); retval = 2; } + + unsigned long long member_size = 0; + for( int i = 19; i >= 12; --i ) + member_size = ( member_size << 8 ) + trailer[i]; + if( member_size != decoder.member_position() ) + { std::fputs( "Member size mismatch\n", stderr ); retval = 2; } + if( retval ) return retval; + } + + if( std::fclose( stdout ) != 0 ) + { std::fprintf( stderr, "Error closing stdout: %s\n", + std::strerror( errno ) ); return 1; } + return 0; + } +@end verbatim + + +@node Concept index +@unnumbered Concept index + +@printindex cp + +@bye diff --git a/encoder.cc b/encoder.cc new file mode 100644 index 0000000..11da3a0 --- /dev/null +++ b/encoder.cc @@ -0,0 +1,594 @@ +/* Lzip - LZMA lossless data compressor + Copyright (C) 2008-2024 Antonio Diaz Diaz. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . +*/ + +#define _FILE_OFFSET_BITS 64 + +#include +#include +#include +#include +#include +#include +#include + +#include "lzip.h" +#include "encoder_base.h" +#include "encoder.h" + + +const CRC32 crc32; + + +int LZ_encoder::get_match_pairs( Pair * pairs ) + { + int len_limit = match_len_limit; + if( len_limit > available_bytes() ) + { + len_limit = available_bytes(); + if( len_limit < 4 ) return 0; + } + + int maxlen = 3; // only used if pairs != 0 + int num_pairs = 0; + const int min_pos = ( pos > dictionary_size ) ? pos - dictionary_size : 0; + const uint8_t * const data = ptr_to_current_pos(); + + unsigned tmp = crc32[data[0]] ^ data[1]; + const int key2 = tmp & ( num_prev_positions2 - 1 ); + tmp ^= (unsigned)data[2] << 8; + const int key3 = num_prev_positions2 + ( tmp & ( num_prev_positions3 - 1 ) ); + const int key4 = num_prev_positions23 + + ( ( tmp ^ ( crc32[data[3]] << 5 ) ) & key4_mask ); + + if( pairs ) + { + const int np2 = prev_positions[key2]; + const int np3 = prev_positions[key3]; + if( np2 > min_pos && buffer[np2-1] == data[0] ) + { + pairs[0].dis = pos - np2; + pairs[0].len = maxlen = 2 + ( np2 == np3 ); + num_pairs = 1; + } + if( np2 != np3 && np3 > min_pos && buffer[np3-1] == data[0] ) + { + maxlen = 3; + pairs[num_pairs++].dis = pos - np3; + } + if( num_pairs > 0 ) + { + const int delta = pairs[num_pairs-1].dis + 1; + while( maxlen < len_limit && data[maxlen-delta] == data[maxlen] ) + ++maxlen; + pairs[num_pairs-1].len = maxlen; + if( maxlen < 3 ) maxlen = 3; + if( maxlen >= len_limit ) pairs = 0; // done. now just skip + } + } + + const int pos1 = pos + 1; + prev_positions[key2] = pos1; + prev_positions[key3] = pos1; + int newpos1 = prev_positions[key4]; + prev_positions[key4] = pos1; + + int32_t * ptr0 = pos_array + ( cyclic_pos << 1 ); + int32_t * ptr1 = ptr0 + 1; + int len = 0, len0 = 0, len1 = 0; + + for( int count = cycles; ; ) + { + if( newpos1 <= min_pos || --count < 0 ) { *ptr0 = *ptr1 = 0; break; } + + const int delta = pos1 - newpos1; + int32_t * const newptr = pos_array + + ( ( cyclic_pos - delta + + ( ( cyclic_pos >= delta ) ? 0 : dictionary_size + 1 ) ) << 1 ); + if( data[len-delta] == data[len] ) + { + while( ++len < len_limit && data[len-delta] == data[len] ) {} + if( pairs && maxlen < len ) + { + pairs[num_pairs].dis = delta - 1; + pairs[num_pairs].len = maxlen = len; + ++num_pairs; + } + if( len >= len_limit ) + { + *ptr0 = newptr[0]; + *ptr1 = newptr[1]; + break; + } + } + if( data[len-delta] < data[len] ) + { + *ptr0 = newpos1; + ptr0 = newptr + 1; + newpos1 = *ptr0; + len0 = len; if( len1 < len ) len = len1; + } + else + { + *ptr1 = newpos1; + ptr1 = newptr; + newpos1 = *ptr1; + len1 = len; if( len0 < len ) len = len0; + } + } + return num_pairs; + } + + +void LZ_encoder::update_distance_prices() + { + for( int dis = start_dis_model; dis < modeled_distances; ++dis ) + { + const int dis_slot = dis_slots[dis]; + const int direct_bits = ( dis_slot >> 1 ) - 1; + const int base = ( 2 | ( dis_slot & 1 ) ) << direct_bits; + const int price = price_symbol_reversed( bm_dis + ( base - dis_slot ), + dis - base, direct_bits ); + for( int len_state = 0; len_state < len_states; ++len_state ) + dis_prices[len_state][dis] = price; + } + + for( int len_state = 0; len_state < len_states; ++len_state ) + { + int * const dsp = dis_slot_prices[len_state]; + const Bit_model * const bmds = bm_dis_slot[len_state]; + int slot = 0; + for( ; slot < end_dis_model; ++slot ) + dsp[slot] = price_symbol6( bmds, slot ); + for( ; slot < num_dis_slots; ++slot ) + dsp[slot] = price_symbol6( bmds, slot ) + + (((( slot >> 1 ) - 1 ) - dis_align_bits ) << price_shift_bits ); + + int * const dp = dis_prices[len_state]; + int dis = 0; + for( ; dis < start_dis_model; ++dis ) + dp[dis] = dsp[dis]; + for( ; dis < modeled_distances; ++dis ) + dp[dis] += dsp[dis_slots[dis]]; + } + } + + +/* Return the number of bytes advanced (ahead). + trials[0]..trials[ahead-1] contain the steps to encode. + ( trials[0].dis4 == -1 ) means literal. + A match/rep longer or equal than match_len_limit finishes the sequence. +*/ +int LZ_encoder::sequence_optimizer( const int reps[num_rep_distances], + const State state ) + { + int num_pairs, num_trials; + + if( pending_num_pairs > 0 ) // from previous call + { + num_pairs = pending_num_pairs; + pending_num_pairs = 0; + } + else + num_pairs = read_match_distances(); + const int main_len = ( num_pairs > 0 ) ? pairs[num_pairs-1].len : 0; + + int replens[num_rep_distances]; + int rep_index = 0; + for( int i = 0; i < num_rep_distances; ++i ) + { + replens[i] = true_match_len( 0, reps[i] + 1 ); + if( replens[i] > replens[rep_index] ) rep_index = i; + } + if( replens[rep_index] >= match_len_limit ) + { + trials[0].price = replens[rep_index]; + trials[0].dis4 = rep_index; + move_and_update( replens[rep_index] ); + return replens[rep_index]; + } + + if( main_len >= match_len_limit ) + { + trials[0].price = main_len; + trials[0].dis4 = pairs[num_pairs-1].dis + num_rep_distances; + move_and_update( main_len ); + return main_len; + } + + const int pos_state = data_position() & pos_state_mask; + const uint8_t prev_byte = peek( 1 ); + const uint8_t cur_byte = peek( 0 ); + const uint8_t match_byte = peek( reps[0] + 1 ); + + trials[1].price = price0( bm_match[state()][pos_state] ); + if( state.is_char() ) + trials[1].price += price_literal( prev_byte, cur_byte ); + else + trials[1].price += price_matched( prev_byte, cur_byte, match_byte ); + trials[1].dis4 = -1; // literal + + const int match_price = price1( bm_match[state()][pos_state] ); + const int rep_match_price = match_price + price1( bm_rep[state()] ); + + if( match_byte == cur_byte ) + trials[1].update( rep_match_price + price_shortrep( state, pos_state ), 0, 0 ); + + num_trials = std::max( main_len, replens[rep_index] ); + + if( num_trials < min_match_len ) + { + trials[0].price = 1; + trials[0].dis4 = trials[1].dis4; + move_pos(); + return 1; + } + + trials[0].state = state; + for( int i = 0; i < num_rep_distances; ++i ) + trials[0].reps[i] = reps[i]; + + for( int len = min_match_len; len <= num_trials; ++len ) + trials[len].price = infinite_price; + + for( int rep = 0; rep < num_rep_distances; ++rep ) + { + if( replens[rep] < min_match_len ) continue; + const int price = rep_match_price + price_rep( rep, state, pos_state ); + for( int len = min_match_len; len <= replens[rep]; ++len ) + trials[len].update( price + rep_len_prices.price( len, pos_state ), + rep, 0 ); + } + + if( main_len > replens[0] ) + { + const int normal_match_price = match_price + price0( bm_rep[state()] ); + int i = 0, len = std::max( replens[0] + 1, (int)min_match_len ); + while( len > pairs[i].len ) ++i; + while( true ) + { + const int dis = pairs[i].dis; + trials[len].update( normal_match_price + price_pair( dis, len, pos_state ), + dis + num_rep_distances, 0 ); + if( ++len > pairs[i].len && ++i >= num_pairs ) break; + } + } + + int cur = 0; + while( true ) // price optimization loop + { + move_pos(); + if( ++cur >= num_trials ) // no more initialized trials + { + backward( cur ); + return cur; + } + + const int num_pairs = read_match_distances(); + const int newlen = ( num_pairs > 0 ) ? pairs[num_pairs-1].len : 0; + if( newlen >= match_len_limit ) + { + pending_num_pairs = num_pairs; + backward( cur ); + return cur; + } + + // give final values to current trial + Trial & cur_trial = trials[cur]; + State cur_state; + { + const int dis4 = cur_trial.dis4; + int prev_index = cur_trial.prev_index; + const int prev_index2 = cur_trial.prev_index2; + + if( prev_index2 == single_step_trial ) + { + cur_state = trials[prev_index].state; + if( prev_index + 1 == cur ) // len == 1 + { + if( dis4 == 0 ) cur_state.set_short_rep(); + else cur_state.set_char(); // literal + } + else if( dis4 < num_rep_distances ) cur_state.set_rep(); + else cur_state.set_match(); + } + else + { + if( prev_index2 == dual_step_trial ) // dis4 == 0 (rep0) + --prev_index; + else // prev_index2 >= 0 + prev_index = prev_index2; + cur_state.set_char_rep(); + } + cur_trial.state = cur_state; + for( int i = 0; i < num_rep_distances; ++i ) + cur_trial.reps[i] = trials[prev_index].reps[i]; + mtf_reps( dis4, cur_trial.reps ); // literal is ignored + } + + const int pos_state = data_position() & pos_state_mask; + const uint8_t prev_byte = peek( 1 ); + const uint8_t cur_byte = peek( 0 ); + const uint8_t match_byte = peek( cur_trial.reps[0] + 1 ); + + int next_price = cur_trial.price + + price0( bm_match[cur_state()][pos_state] ); + if( cur_state.is_char() ) + next_price += price_literal( prev_byte, cur_byte ); + else + next_price += price_matched( prev_byte, cur_byte, match_byte ); + + // try last updates to next trial + Trial & next_trial = trials[cur+1]; + + next_trial.update( next_price, -1, cur ); // literal + + const int match_price = cur_trial.price + price1( bm_match[cur_state()][pos_state] ); + const int rep_match_price = match_price + price1( bm_rep[cur_state()] ); + + if( match_byte == cur_byte && next_trial.dis4 != 0 && + next_trial.prev_index2 == single_step_trial ) + { + const int price = rep_match_price + price_shortrep( cur_state, pos_state ); + if( price <= next_trial.price ) + { + next_trial.price = price; + next_trial.dis4 = 0; // rep0 + next_trial.prev_index = cur; + } + } + + const int triable_bytes = + std::min( available_bytes(), max_num_trials - 1 - cur ); + if( triable_bytes < min_match_len ) continue; + + const int len_limit = std::min( match_len_limit, triable_bytes ); + + // try literal + rep0 + if( match_byte != cur_byte && next_trial.prev_index != cur ) + { + const uint8_t * const data = ptr_to_current_pos(); + const int dis = cur_trial.reps[0] + 1; + const int limit = std::min( match_len_limit + 1, triable_bytes ); + int len = 1; + while( len < limit && data[len-dis] == data[len] ) ++len; + if( --len >= min_match_len ) + { + const int pos_state2 = ( pos_state + 1 ) & pos_state_mask; + State state2 = cur_state; state2.set_char(); + const int price = next_price + + price1( bm_match[state2()][pos_state2] ) + + price1( bm_rep[state2()] ) + + price_rep0_len( len, state2, pos_state2 ); + while( num_trials < cur + 1 + len ) + trials[++num_trials].price = infinite_price; + trials[cur+1+len].update2( price, cur + 1 ); + } + } + + int start_len = min_match_len; + + // try rep distances + for( int rep = 0; rep < num_rep_distances; ++rep ) + { + const uint8_t * const data = ptr_to_current_pos(); + const int dis = cur_trial.reps[rep] + 1; + int len; + + if( data[0-dis] != data[0] || data[1-dis] != data[1] ) continue; + for( len = min_match_len; len < len_limit; ++len ) + if( data[len-dis] != data[len] ) break; + while( num_trials < cur + len ) + trials[++num_trials].price = infinite_price; + int price = rep_match_price + price_rep( rep, cur_state, pos_state ); + for( int i = min_match_len; i <= len; ++i ) + trials[cur+i].update( price + rep_len_prices.price( i, pos_state ), + rep, cur ); + + if( rep == 0 ) start_len = len + 1; // discard shorter matches + + // try rep + literal + rep0 + int len2 = len + 1; + const int limit = std::min( match_len_limit + len2, triable_bytes ); + while( len2 < limit && data[len2-dis] == data[len2] ) ++len2; + len2 -= len + 1; + if( len2 < min_match_len ) continue; + + int pos_state2 = ( pos_state + len ) & pos_state_mask; + State state2 = cur_state; state2.set_rep(); + price += rep_len_prices.price( len, pos_state ) + + price0( bm_match[state2()][pos_state2] ) + + price_matched( data[len-1], data[len], data[len-dis] ); + pos_state2 = ( pos_state2 + 1 ) & pos_state_mask; + state2.set_char(); + price += price1( bm_match[state2()][pos_state2] ) + + price1( bm_rep[state2()] ) + + price_rep0_len( len2, state2, pos_state2 ); + while( num_trials < cur + len + 1 + len2 ) + trials[++num_trials].price = infinite_price; + trials[cur+len+1+len2].update3( price, rep, cur + len + 1, cur ); + } + + // try matches + if( newlen >= start_len && newlen <= len_limit ) + { + const int normal_match_price = match_price + + price0( bm_rep[cur_state()] ); + + while( num_trials < cur + newlen ) + trials[++num_trials].price = infinite_price; + + int i = 0; + while( pairs[i].len < start_len ) ++i; + int dis = pairs[i].dis; + for( int len = start_len; ; ++len ) + { + int price = normal_match_price + price_pair( dis, len, pos_state ); + trials[cur+len].update( price, dis + num_rep_distances, cur ); + + // try match + literal + rep0 + if( len == pairs[i].len ) + { + const uint8_t * const data = ptr_to_current_pos(); + const int dis2 = dis + 1; + int len2 = len + 1; + const int limit = std::min( match_len_limit + len2, triable_bytes ); + while( len2 < limit && data[len2-dis2] == data[len2] ) ++len2; + len2 -= len + 1; + if( len2 >= min_match_len ) + { + int pos_state2 = ( pos_state + len ) & pos_state_mask; + State state2 = cur_state; state2.set_match(); + price += price0( bm_match[state2()][pos_state2] ) + + price_matched( data[len-1], data[len], data[len-dis2] ); + pos_state2 = ( pos_state2 + 1 ) & pos_state_mask; + state2.set_char(); + price += price1( bm_match[state2()][pos_state2] ) + + price1( bm_rep[state2()] ) + + price_rep0_len( len2, state2, pos_state2 ); + + while( num_trials < cur + len + 1 + len2 ) + trials[++num_trials].price = infinite_price; + trials[cur+len+1+len2].update3( price, dis + num_rep_distances, + cur + len + 1, cur ); + } + if( ++i >= num_pairs ) break; + dis = pairs[i].dis; + } + } + } + } + } + + +bool LZ_encoder::encode_member( const unsigned long long member_size ) + { + const unsigned long long member_size_limit = + member_size - Lzip_trailer::size - max_marker_size; + const bool best = ( match_len_limit > 12 ); + const int dis_price_count = best ? 1 : 512; + const int align_price_count = best ? 1 : dis_align_size; + const int price_count = ( match_len_limit > 36 ) ? 1013 : 4093; + int price_counter = 0; // counters may decrement below 0 + int dis_price_counter = 0; + int align_price_counter = 0; + int reps[num_rep_distances]; + State state; + for( int i = 0; i < num_rep_distances; ++i ) reps[i] = 0; + + if( data_position() != 0 || renc.member_position() != Lzip_header::size ) + return false; // can be called only once + + if( !data_finished() ) // encode first byte + { + const uint8_t prev_byte = 0; + const uint8_t cur_byte = peek( 0 ); + renc.encode_bit( bm_match[state()][0], 0 ); + encode_literal( prev_byte, cur_byte ); + crc32.update_byte( crc_, cur_byte ); + get_match_pairs(); + move_pos(); + } + + while( !data_finished() ) + { + if( price_counter <= 0 && pending_num_pairs == 0 ) + { + price_counter = price_count; // recalculate prices every these bytes + if( dis_price_counter <= 0 ) + { dis_price_counter = dis_price_count; update_distance_prices(); } + if( align_price_counter <= 0 ) + { + align_price_counter = align_price_count; + for( int i = 0; i < dis_align_size; ++i ) + align_prices[i] = price_symbol_reversed( bm_align, i, dis_align_bits ); + } + match_len_prices.update_prices(); + rep_len_prices.update_prices(); + } + + int ahead = sequence_optimizer( reps, state ); + price_counter -= ahead; + + for( int i = 0; ahead > 0; ) + { + const int pos_state = ( data_position() - ahead ) & pos_state_mask; + const int len = trials[i].price; + int dis = trials[i].dis4; + + bool bit = ( dis < 0 ); + renc.encode_bit( bm_match[state()][pos_state], !bit ); + if( bit ) // literal byte + { + const uint8_t prev_byte = peek( ahead + 1 ); + const uint8_t cur_byte = peek( ahead ); + crc32.update_byte( crc_, cur_byte ); + if( state.is_char_set_char() ) + encode_literal( prev_byte, cur_byte ); + else + { + const uint8_t match_byte = peek( ahead + reps[0] + 1 ); + encode_matched( prev_byte, cur_byte, match_byte ); + } + } + else // match or repeated match + { + crc32.update_buf( crc_, ptr_to_current_pos() - ahead, len ); + mtf_reps( dis, reps ); + bit = ( dis < num_rep_distances ); + renc.encode_bit( bm_rep[state()], bit ); + if( bit ) // repeated match + { + bit = ( dis == 0 ); + renc.encode_bit( bm_rep0[state()], !bit ); + if( bit ) + renc.encode_bit( bm_len[state()][pos_state], len > 1 ); + else + { + renc.encode_bit( bm_rep1[state()], dis > 1 ); + if( dis > 1 ) + renc.encode_bit( bm_rep2[state()], dis > 2 ); + } + if( len == 1 ) state.set_short_rep(); + else + { + renc.encode_len( rep_len_model, len, pos_state ); + rep_len_prices.decrement_counter( pos_state ); + state.set_rep(); + } + } + else // match + { + dis -= num_rep_distances; + encode_pair( dis, len, pos_state ); + if( dis >= modeled_distances ) --align_price_counter; + --dis_price_counter; + match_len_prices.decrement_counter( pos_state ); + state.set_match(); + } + } + ahead -= len; i += len; + if( renc.member_position() >= member_size_limit ) + { + if( !dec_pos( ahead ) ) return false; + full_flush( state ); + return true; + } + } + } + full_flush( state ); + return true; + } diff --git a/encoder.h b/encoder.h new file mode 100644 index 0000000..2654753 --- /dev/null +++ b/encoder.h @@ -0,0 +1,290 @@ +/* Lzip - LZMA lossless data compressor + Copyright (C) 2008-2024 Antonio Diaz Diaz. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . +*/ + +class Len_prices + { + const Len_model & lm; + const int len_symbols; + const int count; + int prices[pos_states][max_len_symbols]; + int counters[pos_states]; // may decrement below 0 + + void update_low_mid_prices( const int pos_state ) + { + int * const pps = prices[pos_state]; + int tmp = price0( lm.choice1 ); + int len = 0; + for( ; len < len_low_symbols && len < len_symbols; ++len ) + pps[len] = tmp + price_symbol3( lm.bm_low[pos_state], len ); + if( len >= len_symbols ) return; + tmp = price1( lm.choice1 ) + price0( lm.choice2 ); + for( ; len < len_low_symbols + len_mid_symbols && len < len_symbols; ++len ) + pps[len] = tmp + + price_symbol3( lm.bm_mid[pos_state], len - len_low_symbols ); + } + + void update_high_prices() + { + const int tmp = price1( lm.choice1 ) + price1( lm.choice2 ); + for( int len = len_low_symbols + len_mid_symbols; len < len_symbols; ++len ) + // using 4 slots per value makes "price" faster + prices[3][len] = prices[2][len] = prices[1][len] = prices[0][len] = tmp + + price_symbol8( lm.bm_high, len - len_low_symbols - len_mid_symbols ); + } + +public: + void reset() { for( int i = 0; i < pos_states; ++i ) counters[i] = 0; } + + Len_prices( const Len_model & m, const int match_len_limit ) + : + lm( m ), + len_symbols( match_len_limit + 1 - min_match_len ), + count( ( match_len_limit > 12 ) ? 1 : len_symbols ) + { reset(); } + + void decrement_counter( const int pos_state ) { --counters[pos_state]; } + + void update_prices() + { + bool high_pending = false; + for( int pos_state = 0; pos_state < pos_states; ++pos_state ) + if( counters[pos_state] <= 0 ) + { counters[pos_state] = count; + update_low_mid_prices( pos_state ); high_pending = true; } + if( high_pending && len_symbols > len_low_symbols + len_mid_symbols ) + update_high_prices(); + } + + int price( const int len, const int pos_state ) const + { return prices[pos_state][len - min_match_len]; } + }; + + +class LZ_encoder : public LZ_encoder_base + { + struct Pair // distance-length pair + { + int dis; + int len; + }; + + enum { infinite_price = 0x0FFFFFFF, + max_num_trials = 1 << 13, + single_step_trial = -2, + dual_step_trial = -1 }; + + struct Trial + { + State state; + int price; // dual use var; cumulative price, match length + int dis4; // -1 for literal, or rep, or match distance + 4 + int prev_index; // index of prev trial in trials[] + int prev_index2; // -2 trial is single step + // -1 literal + rep0 + // >= 0 ( rep or match ) + literal + rep0 + int reps[num_rep_distances]; + + void update( const int pr, const int distance4, const int p_i ) + { + if( pr < price ) + { price = pr; dis4 = distance4; prev_index = p_i; + prev_index2 = single_step_trial; } + } + + void update2( const int pr, const int p_i ) + { + if( pr < price ) + { price = pr; dis4 = 0; prev_index = p_i; + prev_index2 = dual_step_trial; } + } + + void update3( const int pr, const int distance4, const int p_i, + const int p_i2 ) + { + if( pr < price ) + { price = pr; dis4 = distance4; prev_index = p_i; + prev_index2 = p_i2; } + } + }; + + const int cycles; + const int match_len_limit; + Len_prices match_len_prices; + Len_prices rep_len_prices; + int pending_num_pairs; + Pair pairs[max_match_len+1]; + Trial trials[max_num_trials]; + + int dis_slot_prices[len_states][2*max_dictionary_bits]; + int dis_prices[len_states][modeled_distances]; + int align_prices[dis_align_size]; + const int num_dis_slots; + + bool dec_pos( const int ahead ) + { + if( ahead < 0 || pos < ahead ) return false; + pos -= ahead; + if( cyclic_pos < ahead ) cyclic_pos += dictionary_size + 1; + cyclic_pos -= ahead; + return true; + } + + int get_match_pairs( Pair * pairs = 0 ); + void update_distance_prices(); + + // move-to-front dis in/into reps; do nothing if( dis4 <= 0 ) + static void mtf_reps( const int dis4, int reps[num_rep_distances] ) + { + if( dis4 >= num_rep_distances ) // match + { + reps[3] = reps[2]; reps[2] = reps[1]; reps[1] = reps[0]; + reps[0] = dis4 - num_rep_distances; + } + else if( dis4 > 0 ) // repeated match + { + const int distance = reps[dis4]; + for( int i = dis4; i > 0; --i ) reps[i] = reps[i-1]; + reps[0] = distance; + } + } + + int price_shortrep( const State state, const int pos_state ) const + { + return price0( bm_rep0[state()] ) + price0( bm_len[state()][pos_state] ); + } + + int price_rep( const int rep, const State state, const int pos_state ) const + { + if( rep == 0 ) return price0( bm_rep0[state()] ) + + price1( bm_len[state()][pos_state] ); + int price = price1( bm_rep0[state()] ); + if( rep == 1 ) + price += price0( bm_rep1[state()] ); + else + { + price += price1( bm_rep1[state()] ); + price += price_bit( bm_rep2[state()], rep - 2 ); + } + return price; + } + + int price_rep0_len( const int len, const State state, const int pos_state ) const + { + return price_rep( 0, state, pos_state ) + + rep_len_prices.price( len, pos_state ); + } + + int price_pair( const int dis, const int len, const int pos_state ) const + { + const int price = match_len_prices.price( len, pos_state ); + const int len_state = get_len_state( len ); + if( dis < modeled_distances ) + return price + dis_prices[len_state][dis]; + else + return price + dis_slot_prices[len_state][get_slot( dis )] + + align_prices[dis & (dis_align_size - 1)]; + } + + int read_match_distances() + { + const int num_pairs = get_match_pairs( pairs ); + if( num_pairs > 0 ) + { + const int len = pairs[num_pairs-1].len; + if( len == match_len_limit && len < max_match_len ) + pairs[num_pairs-1].len = + true_match_len( len, pairs[num_pairs-1].dis + 1 ); + } + return num_pairs; + } + + void move_and_update( int n ) + { + while( true ) + { + move_pos(); + if( --n <= 0 ) break; + get_match_pairs(); + } + } + + void backward( int cur ) + { + int dis4 = trials[cur].dis4; + while( cur > 0 ) + { + const int prev_index = trials[cur].prev_index; + Trial & prev_trial = trials[prev_index]; + + if( trials[cur].prev_index2 != single_step_trial ) + { + prev_trial.dis4 = -1; // literal + prev_trial.prev_index = prev_index - 1; + prev_trial.prev_index2 = single_step_trial; + if( trials[cur].prev_index2 >= 0 ) + { + Trial & prev_trial2 = trials[prev_index-1]; + prev_trial2.dis4 = dis4; dis4 = 0; // rep0 + prev_trial2.prev_index = trials[cur].prev_index2; + prev_trial2.prev_index2 = single_step_trial; + } + } + prev_trial.price = cur - prev_index; // len + cur = dis4; dis4 = prev_trial.dis4; prev_trial.dis4 = cur; + cur = prev_index; + } + } + + int sequence_optimizer( const int reps[num_rep_distances], + const State state ); + + enum { before_size = max_num_trials, + // bytes to keep in buffer after pos + after_size = ( 2 * max_match_len ) + 1, + dict_factor = 2, + num_prev_positions3 = 1 << 16, + num_prev_positions2 = 1 << 10, + num_prev_positions23 = num_prev_positions2 + num_prev_positions3, + pos_array_factor = 2 }; + +public: + LZ_encoder( const int dict_size, const int len_limit, + const int ifd, const int outfd ) + : + LZ_encoder_base( before_size, dict_size, after_size, dict_factor, + num_prev_positions23, pos_array_factor, ifd, outfd ), + cycles( ( len_limit < max_match_len ) ? 16 + ( len_limit / 2 ) : 256 ), + match_len_limit( len_limit ), + match_len_prices( match_len_model, match_len_limit ), + rep_len_prices( rep_len_model, match_len_limit ), + pending_num_pairs( 0 ), + num_dis_slots( 2 * real_bits( dictionary_size - 1 ) ) + { + trials[1].prev_index = 0; + trials[1].prev_index2 = single_step_trial; + } + + void reset() + { + LZ_encoder_base::reset(); + match_len_prices.reset(); + rep_len_prices.reset(); + pending_num_pairs = 0; + } + + bool encode_member( const unsigned long long member_size ); + }; diff --git a/encoder_base.cc b/encoder_base.cc new file mode 100644 index 0000000..69abd52 --- /dev/null +++ b/encoder_base.cc @@ -0,0 +1,192 @@ +/* Lzip - LZMA lossless data compressor + Copyright (C) 2008-2024 Antonio Diaz Diaz. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . +*/ + +#define _FILE_OFFSET_BITS 64 + +#include +#include +#include +#include +#include +#include +#include +#include + +#include "lzip.h" +#include "encoder_base.h" + + +Dis_slots dis_slots; +Prob_prices prob_prices; + + +bool Matchfinder_base::read_block() + { + if( !at_stream_end && stream_pos < buffer_size ) + { + const int size = buffer_size - stream_pos; + const int rd = readblock( infd, buffer + stream_pos, size ); + stream_pos += rd; + if( rd != size && errno ) throw Error( "Read error" ); + if( rd < size ) { at_stream_end = true; pos_limit = buffer_size; } + } + return pos < stream_pos; + } + + +void Matchfinder_base::normalize_pos() + { + if( pos > stream_pos ) + internal_error( "pos > stream_pos in normalize_pos." ); + if( !at_stream_end ) + { + // offset is int32_t for the std::min below + const int32_t offset = pos - before_size - dictionary_size; + const int size = stream_pos - offset; + std::memmove( buffer, buffer + offset, size ); + partial_data_pos += offset; + pos -= offset; // pos = before_size + dictionary_size + stream_pos -= offset; + for( int i = 0; i < num_prev_positions; ++i ) + prev_positions[i] -= std::min( prev_positions[i], offset ); + for( int i = 0; i < pos_array_size; ++i ) + pos_array[i] -= std::min( pos_array[i], offset ); + read_block(); + } + } + + +Matchfinder_base::Matchfinder_base( const int before_size_, + const int dict_size, const int after_size, + const int dict_factor, const int num_prev_positions23_, + const int pos_array_factor, const int ifd ) + : + partial_data_pos( 0 ), + before_size( before_size_ ), + pos( 0 ), + cyclic_pos( 0 ), + stream_pos( 0 ), + num_prev_positions23( num_prev_positions23_ ), + infd( ifd ), + at_stream_end( false ) + { + const int buffer_size_limit = + ( dict_factor * dict_size ) + before_size + after_size; + buffer_size = std::max( 65536, dict_size ); + buffer = (uint8_t *)std::malloc( buffer_size ); + if( !buffer ) throw std::bad_alloc(); + if( read_block() && !at_stream_end && buffer_size < buffer_size_limit ) + { + uint8_t * const tmp = (uint8_t *)std::realloc( buffer, buffer_size_limit ); + if( !tmp ) { std::free( buffer ); throw std::bad_alloc(); } + buffer = tmp; + buffer_size = buffer_size_limit; + read_block(); + } + if( at_stream_end && stream_pos < dict_size ) + dictionary_size = std::max( (int)min_dictionary_size, stream_pos ); + else + dictionary_size = dict_size; + pos_limit = buffer_size; + if( !at_stream_end ) pos_limit -= after_size; + unsigned size = 1 << std::max( 16, real_bits( dictionary_size - 1 ) - 2 ); + if( dictionary_size > 1 << 26 ) size >>= 1; // 64 MiB + key4_mask = size - 1; // increases with dictionary size + size += num_prev_positions23; + num_prev_positions = size; + + pos_array_size = pos_array_factor * ( dictionary_size + 1 ); + size += pos_array_size; + if( size * sizeof prev_positions[0] <= size ) prev_positions = 0; + else prev_positions = new( std::nothrow ) int32_t[size]; + if( !prev_positions ) { std::free( buffer ); throw std::bad_alloc(); } + pos_array = prev_positions + num_prev_positions; + for( int i = 0; i < num_prev_positions; ++i ) prev_positions[i] = 0; + } + + +void Matchfinder_base::reset() + { + if( stream_pos > pos ) + std::memmove( buffer, buffer + pos, stream_pos - pos ); + partial_data_pos = 0; + stream_pos -= pos; + pos = 0; + cyclic_pos = 0; + read_block(); + if( at_stream_end && stream_pos < dictionary_size ) + { + dictionary_size = std::max( (int)min_dictionary_size, stream_pos ); + int size = 1 << std::max( 16, real_bits( dictionary_size - 1 ) - 2 ); + if( dictionary_size > 1 << 26 ) size >>= 1; // 64 MiB + key4_mask = size - 1; + size += num_prev_positions23; + num_prev_positions = size; + pos_array = prev_positions + num_prev_positions; + } + for( int i = 0; i < num_prev_positions; ++i ) prev_positions[i] = 0; + } + + +void Range_encoder::flush_data() + { + if( pos > 0 ) + { + if( outfd >= 0 && writeblock( outfd, buffer, pos ) != pos ) + throw Error( "Write error" ); + partial_member_pos += pos; + pos = 0; + show_cprogress(); + } + } + + +// End Of Stream marker => (dis == 0xFFFFFFFFU, len == min_match_len) +void LZ_encoder_base::full_flush( const State state ) + { + const int pos_state = data_position() & pos_state_mask; + renc.encode_bit( bm_match[state()][pos_state], 1 ); + renc.encode_bit( bm_rep[state()], 0 ); + encode_pair( 0xFFFFFFFFU, min_match_len, pos_state ); + renc.flush(); + Lzip_trailer trailer; + trailer.data_crc( crc() ); + trailer.data_size( data_position() ); + trailer.member_size( renc.member_position() + trailer.size ); + for( int i = 0; i < trailer.size; ++i ) renc.put_byte( trailer.data[i] ); + renc.flush_data(); + } + + +void LZ_encoder_base::reset() + { + Matchfinder_base::reset(); + crc_ = 0xFFFFFFFFU; + bm_literal[0][0].reset( (1 << literal_context_bits) * 0x300 ); + bm_match[0][0].reset( State::states * pos_states ); + bm_rep[0].reset( State::states ); + bm_rep0[0].reset( State::states ); + bm_rep1[0].reset( State::states ); + bm_rep2[0].reset( State::states ); + bm_len[0][0].reset( State::states * pos_states ); + bm_dis_slot[0][0].reset( len_states * (1 << dis_slot_bits) ); + bm_dis[0].reset( modeled_distances - end_dis_model + 1 ); + bm_align[0].reset( dis_align_size ); + match_len_model.reset(); + rep_len_model.reset(); + renc.reset( dictionary_size ); + } diff --git a/encoder_base.h b/encoder_base.h new file mode 100644 index 0000000..ef48e0c --- /dev/null +++ b/encoder_base.h @@ -0,0 +1,482 @@ +/* Lzip - LZMA lossless data compressor + Copyright (C) 2008-2024 Antonio Diaz Diaz. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . +*/ + +enum { price_shift_bits = 6, + price_step_bits = 2, + price_step = 1 << price_step_bits }; + +class Dis_slots + { + uint8_t data[1<<10]; + +public: + void init() + { + for( int slot = 0; slot < 4; ++slot ) data[slot] = slot; + for( int i = 4, size = 2, slot = 4; slot < 20; slot += 2 ) + { + std::memset( &data[i], slot, size ); + std::memset( &data[i+size], slot + 1, size ); + size <<= 1; + i += size; + } + } + + uint8_t operator[]( const int dis ) const { return data[dis]; } + }; + +extern Dis_slots dis_slots; + +inline uint8_t get_slot( const unsigned dis ) + { + if( dis < (1 << 10) ) return dis_slots[dis]; + if( dis < (1 << 19) ) return dis_slots[dis>> 9] + 18; + if( dis < (1 << 28) ) return dis_slots[dis>>18] + 36; + return dis_slots[dis>>27] + 54; + } + + +class Prob_prices + { + short data[bit_model_total >> price_step_bits]; + +public: + void init() + { + for( int i = 0; i < bit_model_total >> price_step_bits; ++i ) + { + unsigned val = ( i * price_step ) + ( price_step / 2 ); + int bits = 0; // base 2 logarithm of val + for( int j = 0; j < price_shift_bits; ++j ) + { + val = val * val; + bits <<= 1; + while( val >= 1 << 16 ) { val >>= 1; ++bits; } + } + bits += 15; // remaining bits in val + data[i] = ( bit_model_total_bits << price_shift_bits ) - bits; + } + } + + int operator[]( const int probability ) const + { return data[probability >> price_step_bits]; } + }; + +extern Prob_prices prob_prices; + + +inline int price0( const Bit_model bm ) + { return prob_prices[bm.probability]; } + +inline int price1( const Bit_model bm ) + { return prob_prices[bit_model_total - bm.probability]; } + +inline int price_bit( const Bit_model bm, const bool bit ) + { return bit ? price1( bm ) : price0( bm ); } + + +inline int price_symbol3( const Bit_model bm[], int symbol ) + { + bool bit = symbol & 1; + symbol |= 8; symbol >>= 1; + int price = price_bit( bm[symbol], bit ); + bit = symbol & 1; symbol >>= 1; price += price_bit( bm[symbol], bit ); + return price + price_bit( bm[1], symbol & 1 ); + } + + +inline int price_symbol6( const Bit_model bm[], unsigned symbol ) + { + bool bit = symbol & 1; + symbol |= 64; symbol >>= 1; + int price = price_bit( bm[symbol], bit ); + bit = symbol & 1; symbol >>= 1; price += price_bit( bm[symbol], bit ); + bit = symbol & 1; symbol >>= 1; price += price_bit( bm[symbol], bit ); + bit = symbol & 1; symbol >>= 1; price += price_bit( bm[symbol], bit ); + bit = symbol & 1; symbol >>= 1; price += price_bit( bm[symbol], bit ); + return price + price_bit( bm[1], symbol & 1 ); + } + + +inline int price_symbol8( const Bit_model bm[], int symbol ) + { + bool bit = symbol & 1; + symbol |= 0x100; symbol >>= 1; + int price = price_bit( bm[symbol], bit ); + bit = symbol & 1; symbol >>= 1; price += price_bit( bm[symbol], bit ); + bit = symbol & 1; symbol >>= 1; price += price_bit( bm[symbol], bit ); + bit = symbol & 1; symbol >>= 1; price += price_bit( bm[symbol], bit ); + bit = symbol & 1; symbol >>= 1; price += price_bit( bm[symbol], bit ); + bit = symbol & 1; symbol >>= 1; price += price_bit( bm[symbol], bit ); + bit = symbol & 1; symbol >>= 1; price += price_bit( bm[symbol], bit ); + return price + price_bit( bm[1], symbol & 1 ); + } + + +inline int price_symbol_reversed( const Bit_model bm[], int symbol, + const int num_bits ) + { + int price = 0; + int model = 1; + for( int i = num_bits; i > 0; --i ) + { + const bool bit = symbol & 1; + symbol >>= 1; + price += price_bit( bm[model], bit ); + model <<= 1; model |= bit; + } + return price; + } + + +inline int price_matched( const Bit_model bm[], unsigned symbol, + unsigned match_byte ) + { + int price = 0; + unsigned mask = 0x100; + symbol |= mask; + while( true ) + { + const unsigned match_bit = ( match_byte <<= 1 ) & mask; + const bool bit = ( symbol <<= 1 ) & 0x100; + price += price_bit( bm[(symbol>>9)+match_bit+mask], bit ); + if( symbol >= 0x10000 ) return price; + mask &= ~(match_bit ^ symbol); // if( match_bit != bit ) mask = 0; + } + } + + +class Matchfinder_base + { + bool read_block(); + void normalize_pos(); + + Matchfinder_base( const Matchfinder_base & ); // declared as private + void operator=( const Matchfinder_base & ); // declared as private + +protected: + unsigned long long partial_data_pos; + uint8_t * buffer; // input buffer + int32_t * prev_positions; // 1 + last seen position of key. else 0 + int32_t * pos_array; // may be tree or chain + const int before_size; // bytes to keep in buffer before dictionary + int buffer_size; + int dictionary_size; // bytes to keep in buffer before pos + int pos; // current pos in buffer + int cyclic_pos; // cycles through [0, dictionary_size] + int stream_pos; // first byte not yet read from file + int pos_limit; // when reached, a new block must be read + int key4_mask; + const int num_prev_positions23; + int num_prev_positions; // size of prev_positions + int pos_array_size; + const int infd; // input file descriptor + bool at_stream_end; // stream_pos shows real end of file + + Matchfinder_base( const int before_size_, + const int dict_size, const int after_size, + const int dict_factor, const int num_prev_positions23_, + const int pos_array_factor, const int ifd ); + + ~Matchfinder_base() + { delete[] prev_positions; std::free( buffer ); } + +public: + uint8_t peek( const int distance ) const { return buffer[pos-distance]; } + int available_bytes() const { return stream_pos - pos; } + unsigned long long data_position() const { return partial_data_pos + pos; } + bool data_finished() const { return at_stream_end && pos >= stream_pos; } + const uint8_t * ptr_to_current_pos() const { return buffer + pos; } + + int true_match_len( const int index, const int distance ) const + { + const uint8_t * const data = buffer + pos; + int i = index; + const int len_limit = std::min( available_bytes(), (int)max_match_len ); + while( i < len_limit && data[i-distance] == data[i] ) ++i; + return i; + } + + void move_pos() + { + if( ++cyclic_pos > dictionary_size ) cyclic_pos = 0; + if( ++pos >= pos_limit ) normalize_pos(); + } + + void reset(); + }; + + +class Range_encoder + { + enum { buffer_size = 65536 }; + uint64_t low; + unsigned long long partial_member_pos; + uint8_t * const buffer; // output buffer + int pos; // current pos in buffer + uint32_t range; + unsigned ff_count; + const int outfd; // output file descriptor + uint8_t cache; + Lzip_header header; + + void shift_low() + { + if( low >> 24 != 0xFF ) + { + const bool carry = ( low > 0xFFFFFFFFU ); + put_byte( cache + carry ); + for( ; ff_count > 0; --ff_count ) put_byte( 0xFF + carry ); + cache = low >> 24; + } + else ++ff_count; + low = ( low & 0x00FFFFFFU ) << 8; + } + + Range_encoder( const Range_encoder & ); // declared as private + void operator=( const Range_encoder & ); // declared as private + +public: + void reset( const unsigned dictionary_size ) + { + low = 0; + partial_member_pos = 0; + pos = 0; + range = 0xFFFFFFFFU; + ff_count = 0; + cache = 0; + header.dictionary_size( dictionary_size ); + for( int i = 0; i < header.size; ++i ) put_byte( header.data[i] ); + } + + Range_encoder( const unsigned dictionary_size, const int ofd ) + : + buffer( new uint8_t[buffer_size] ), outfd( ofd ) + { + header.set_magic(); + reset( dictionary_size ); + } + + ~Range_encoder() { delete[] buffer; } + + unsigned long long member_position() const + { return partial_member_pos + pos + ff_count; } + + void flush() { for( int i = 0; i < 5; ++i ) shift_low(); } + void flush_data(); + + void put_byte( const uint8_t b ) + { + buffer[pos] = b; + if( ++pos >= buffer_size ) flush_data(); + } + + void encode( const int symbol, const int num_bits ) + { + for( unsigned mask = 1 << ( num_bits - 1 ); mask > 0; mask >>= 1 ) + { + range >>= 1; + if( symbol & mask ) low += range; + if( range <= 0x00FFFFFFU ) { range <<= 8; shift_low(); } + } + } + + void encode_bit( Bit_model & bm, const bool bit ) + { + const uint32_t bound = ( range >> bit_model_total_bits ) * bm.probability; + if( !bit ) + { + range = bound; + bm.probability += + ( bit_model_total - bm.probability ) >> bit_model_move_bits; + } + else + { + low += bound; + range -= bound; + bm.probability -= bm.probability >> bit_model_move_bits; + } + if( range <= 0x00FFFFFFU ) { range <<= 8; shift_low(); } + } + + void encode_tree3( Bit_model bm[], const int symbol ) + { + bool bit = ( symbol >> 2 ) & 1; + encode_bit( bm[1], bit ); + int model = 2 | bit; + bit = ( symbol >> 1 ) & 1; + encode_bit( bm[model], bit ); model <<= 1; model |= bit; + encode_bit( bm[model], symbol & 1 ); + } + + void encode_tree6( Bit_model bm[], const unsigned symbol ) + { + bool bit = ( symbol >> 5 ) & 1; + encode_bit( bm[1], bit ); + int model = 2 | bit; + bit = ( symbol >> 4 ) & 1; + encode_bit( bm[model], bit ); model <<= 1; model |= bit; + bit = ( symbol >> 3 ) & 1; + encode_bit( bm[model], bit ); model <<= 1; model |= bit; + bit = ( symbol >> 2 ) & 1; + encode_bit( bm[model], bit ); model <<= 1; model |= bit; + bit = ( symbol >> 1 ) & 1; + encode_bit( bm[model], bit ); model <<= 1; model |= bit; + encode_bit( bm[model], symbol & 1 ); + } + + void encode_tree8( Bit_model bm[], const int symbol ) + { + int model = 1; + for( int i = 7; i >= 0; --i ) + { + const bool bit = ( symbol >> i ) & 1; + encode_bit( bm[model], bit ); + model <<= 1; model |= bit; + } + } + + void encode_tree_reversed( Bit_model bm[], int symbol, const int num_bits ) + { + int model = 1; + for( int i = num_bits; i > 0; --i ) + { + const bool bit = symbol & 1; + symbol >>= 1; + encode_bit( bm[model], bit ); + model <<= 1; model |= bit; + } + } + + void encode_matched( Bit_model bm[], unsigned symbol, unsigned match_byte ) + { + unsigned mask = 0x100; + symbol |= mask; + while( true ) + { + const unsigned match_bit = ( match_byte <<= 1 ) & mask; + const bool bit = ( symbol <<= 1 ) & 0x100; + encode_bit( bm[(symbol>>9)+match_bit+mask], bit ); + if( symbol >= 0x10000 ) break; + mask &= ~(match_bit ^ symbol); // if( match_bit != bit ) mask = 0; + } + } + + void encode_len( Len_model & lm, int symbol, const int pos_state ) + { + bool bit = ( ( symbol -= min_match_len ) >= len_low_symbols ); + encode_bit( lm.choice1, bit ); + if( !bit ) + encode_tree3( lm.bm_low[pos_state], symbol ); + else + { + bit = ( ( symbol -= len_low_symbols ) >= len_mid_symbols ); + encode_bit( lm.choice2, bit ); + if( !bit ) + encode_tree3( lm.bm_mid[pos_state], symbol ); + else + encode_tree8( lm.bm_high, symbol - len_mid_symbols ); + } + } + }; + + +class LZ_encoder_base : public Matchfinder_base + { +protected: + enum { max_marker_size = 16, + num_rep_distances = 4 }; // must be 4 + + uint32_t crc_; + + Bit_model bm_literal[1<= start_dis_model ) + { + const int direct_bits = ( dis_slot >> 1 ) - 1; + const unsigned base = ( 2 | ( dis_slot & 1 ) ) << direct_bits; + const unsigned direct_dis = dis - base; + + if( dis_slot < end_dis_model ) + renc.encode_tree_reversed( bm_dis + ( base - dis_slot ), + direct_dis, direct_bits ); + else + { + renc.encode( direct_dis >> dis_align_bits, direct_bits - dis_align_bits ); + renc.encode_tree_reversed( bm_align, direct_dis, dis_align_bits ); + } + } + } + + void full_flush( const State state ); + +public: + virtual ~LZ_encoder_base() {} + + unsigned long long member_position() const { return renc.member_position(); } + virtual void reset(); + + virtual bool encode_member( const unsigned long long member_size ) = 0; + }; diff --git a/fast_encoder.cc b/fast_encoder.cc new file mode 100644 index 0000000..c6ec497 --- /dev/null +++ b/fast_encoder.cc @@ -0,0 +1,184 @@ +/* Lzip - LZMA lossless data compressor + Copyright (C) 2008-2024 Antonio Diaz Diaz. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . +*/ + +#define _FILE_OFFSET_BITS 64 + +#include +#include +#include +#include +#include +#include +#include + +#include "lzip.h" +#include "encoder_base.h" +#include "fast_encoder.h" + + +int FLZ_encoder::longest_match_len( int * const distance ) + { + enum { len_limit = 16 }; + const int available = std::min( available_bytes(), (int)max_match_len ); + if( available < len_limit ) return 0; + + const uint8_t * const data = ptr_to_current_pos(); + key4 = ( ( key4 << 4 ) ^ data[3] ) & key4_mask; + const int pos1 = pos + 1; + int newpos1 = prev_positions[key4]; + prev_positions[key4] = pos1; + int32_t * ptr0 = pos_array + cyclic_pos; + int maxlen = 0; + + for( int count = 4; ; ) + { + int delta; + if( newpos1 <= 0 || --count < 0 || + ( delta = pos1 - newpos1 ) > dictionary_size ) { *ptr0 = 0; break; } + int32_t * const newptr = pos_array + + ( cyclic_pos - delta + + ( ( cyclic_pos >= delta ) ? 0 : dictionary_size + 1 ) ); + + if( data[maxlen-delta] == data[maxlen] ) + { + int len = 0; + while( len < available && data[len-delta] == data[len] ) ++len; + if( maxlen < len ) + { maxlen = len; *distance = delta - 1; + if( maxlen >= len_limit ) { *ptr0 = *newptr; break; } } + } + + *ptr0 = newpos1; + ptr0 = newptr; + newpos1 = *ptr0; + } + return maxlen; + } + + +bool FLZ_encoder::encode_member( const unsigned long long member_size ) + { + const unsigned long long member_size_limit = + member_size - Lzip_trailer::size - max_marker_size; + int rep = 0; + int reps[num_rep_distances]; + State state; + for( int i = 0; i < num_rep_distances; ++i ) reps[i] = 0; + + if( data_position() != 0 || renc.member_position() != Lzip_header::size ) + return false; // can be called only once + + if( !data_finished() ) // encode first byte + { + const uint8_t prev_byte = 0; + const uint8_t cur_byte = peek( 0 ); + renc.encode_bit( bm_match[state()][0], 0 ); + encode_literal( prev_byte, cur_byte ); + crc32.update_byte( crc_, cur_byte ); + reset_key4(); + update_and_move( 1 ); + } + + while( !data_finished() && renc.member_position() < member_size_limit ) + { + int match_distance; + const int main_len = longest_match_len( &match_distance ); + const int pos_state = data_position() & pos_state_mask; + int len = 0; + + for( int i = 0; i < num_rep_distances; ++i ) + { + const int tlen = true_match_len( 0, reps[i] + 1 ); + if( tlen > len ) { len = tlen; rep = i; } + } + if( len > min_match_len && len + 3 > main_len ) + { + crc32.update_buf( crc_, ptr_to_current_pos(), len ); + renc.encode_bit( bm_match[state()][pos_state], 1 ); + renc.encode_bit( bm_rep[state()], 1 ); + renc.encode_bit( bm_rep0[state()], rep != 0 ); + if( rep == 0 ) + renc.encode_bit( bm_len[state()][pos_state], 1 ); + else + { + renc.encode_bit( bm_rep1[state()], rep > 1 ); + if( rep > 1 ) + renc.encode_bit( bm_rep2[state()], rep > 2 ); + const int distance = reps[rep]; + for( int i = rep; i > 0; --i ) reps[i] = reps[i-1]; + reps[0] = distance; + } + state.set_rep(); + renc.encode_len( rep_len_model, len, pos_state ); + move_pos(); + update_and_move( len - 1 ); + continue; + } + + if( main_len > min_match_len ) + { + crc32.update_buf( crc_, ptr_to_current_pos(), main_len ); + renc.encode_bit( bm_match[state()][pos_state], 1 ); + renc.encode_bit( bm_rep[state()], 0 ); + state.set_match(); + for( int i = num_rep_distances - 1; i > 0; --i ) reps[i] = reps[i-1]; + reps[0] = match_distance; + encode_pair( match_distance, main_len, pos_state ); + move_pos(); + update_and_move( main_len - 1 ); + continue; + } + + const uint8_t prev_byte = peek( 1 ); + const uint8_t cur_byte = peek( 0 ); + const uint8_t match_byte = peek( reps[0] + 1 ); + move_pos(); + crc32.update_byte( crc_, cur_byte ); + + if( match_byte == cur_byte ) + { + const int short_rep_price = price1( bm_match[state()][pos_state] ) + + price1( bm_rep[state()] ) + + price0( bm_rep0[state()] ) + + price0( bm_len[state()][pos_state] ); + int price = price0( bm_match[state()][pos_state] ); + if( state.is_char() ) + price += price_literal( prev_byte, cur_byte ); + else + price += price_matched( prev_byte, cur_byte, match_byte ); + if( short_rep_price < price ) + { + renc.encode_bit( bm_match[state()][pos_state], 1 ); + renc.encode_bit( bm_rep[state()], 1 ); + renc.encode_bit( bm_rep0[state()], 0 ); + renc.encode_bit( bm_len[state()][pos_state], 0 ); + state.set_short_rep(); + continue; + } + } + + // literal byte + renc.encode_bit( bm_match[state()][pos_state], 0 ); + if( state.is_char_set_char() ) + encode_literal( prev_byte, cur_byte ); + else + encode_matched( prev_byte, cur_byte, match_byte ); + } + + full_flush( state ); + return true; + } diff --git a/fast_encoder.h b/fast_encoder.h new file mode 100644 index 0000000..e4c97dc --- /dev/null +++ b/fast_encoder.h @@ -0,0 +1,61 @@ +/* Lzip - LZMA lossless data compressor + Copyright (C) 2008-2024 Antonio Diaz Diaz. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . +*/ + +class FLZ_encoder : public LZ_encoder_base + { + unsigned key4; // key made from latest 4 bytes + + void reset_key4() + { + key4 = 0; + for( int i = 0; i < 3 && i < available_bytes(); ++i ) + key4 = ( key4 << 4 ) ^ buffer[i]; + } + + int longest_match_len( int * const distance ); + + void update_and_move( int n ) + { + while( --n >= 0 ) + { + if( available_bytes() >= 4 ) + { + key4 = ( ( key4 << 4 ) ^ buffer[pos+3] ) & key4_mask; + pos_array[cyclic_pos] = prev_positions[key4]; + prev_positions[key4] = pos + 1; + } + move_pos(); + } + } + + enum { before_size = 0, + dict_size = 65536, + // bytes to keep in buffer after pos + after_size = max_match_len, + dict_factor = 16, + num_prev_positions23 = 0, + pos_array_factor = 1 }; + +public: + FLZ_encoder( const int ifd, const int outfd ) + : + LZ_encoder_base( before_size, dict_size, after_size, dict_factor, + num_prev_positions23, pos_array_factor, ifd, outfd ) + {} + + bool encode_member( const unsigned long long member_size ); + }; diff --git a/list.cc b/list.cc new file mode 100644 index 0000000..cf68a31 --- /dev/null +++ b/list.cc @@ -0,0 +1,114 @@ +/* Lzip - LZMA lossless data compressor + Copyright (C) 2008-2024 Antonio Diaz Diaz. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . +*/ + +#define _FILE_OFFSET_BITS 64 + +#include +#include +#include +#include +#include +#include +#include + +#include "lzip.h" +#include "lzip_index.h" + + +namespace { + +void list_line( const unsigned long long uncomp_size, + const unsigned long long comp_size, + const char * const input_filename ) + { + if( uncomp_size > 0 ) + std::printf( "%14llu %14llu %6.2f%% %s\n", uncomp_size, comp_size, + 100.0 - ( ( 100.0 * comp_size ) / uncomp_size ), + input_filename ); + else + std::printf( "%14llu %14llu -INF%% %s\n", uncomp_size, comp_size, + input_filename ); + } + +} // end namespace + + +int list_files( const std::vector< std::string > & filenames, + const Cl_options & cl_opts ) + { + unsigned long long total_comp = 0, total_uncomp = 0; + int files = 0, retval = 0; + bool first_post = true; + bool stdin_used = false; + + for( unsigned i = 0; i < filenames.size(); ++i ) + { + const bool from_stdin = ( filenames[i] == "-" ); + if( from_stdin ) { if( stdin_used ) continue; else stdin_used = true; } + const char * const input_filename = + from_stdin ? "(stdin)" : filenames[i].c_str(); + struct stat in_stats; // not used + const int infd = from_stdin ? STDIN_FILENO : + open_instream( input_filename, &in_stats, false, true ); + if( infd < 0 ) { set_retval( retval, 1 ); continue; } + + const Lzip_index lzip_index( infd, cl_opts ); + close( infd ); + if( lzip_index.retval() != 0 ) + { + show_file_error( input_filename, lzip_index.error().c_str() ); + set_retval( retval, lzip_index.retval() ); + continue; + } + if( verbosity < 0 ) continue; + const unsigned long long udata_size = lzip_index.udata_size(); + const unsigned long long cdata_size = lzip_index.cdata_size(); + total_comp += cdata_size; total_uncomp += udata_size; ++files; + const long members = lzip_index.members(); + if( first_post ) + { + first_post = false; + if( verbosity >= 1 ) std::fputs( " dict memb trail ", stdout ); + std::fputs( " uncompressed compressed saved name\n", stdout ); + } + if( verbosity >= 1 ) + std::printf( "%s %5ld %6lld ", format_ds( lzip_index.dictionary_size() ), + members, lzip_index.file_size() - cdata_size ); + list_line( udata_size, cdata_size, input_filename ); + + if( verbosity >= 2 && members > 1 ) + { + std::fputs( " member data_pos data_size member_pos member_size\n", stdout ); + for( long i = 0; i < members; ++i ) + { + const Block & db = lzip_index.dblock( i ); + const Block & mb = lzip_index.mblock( i ); + std::printf( "%6ld %14llu %14llu %14llu %14llu\n", + i + 1, db.pos(), db.size(), mb.pos(), mb.size() ); + } + first_post = true; // reprint heading after list of members + } + std::fflush( stdout ); + } + if( verbosity >= 0 && files > 1 ) + { + if( verbosity >= 1 ) std::fputs( " ", stdout ); + list_line( total_uncomp, total_comp, "(totals)" ); + std::fflush( stdout ); + } + return retval; + } diff --git a/lzip.h b/lzip.h new file mode 100644 index 0000000..dec033c --- /dev/null +++ b/lzip.h @@ -0,0 +1,372 @@ +/* Lzip - LZMA lossless data compressor + Copyright (C) 2008-2024 Antonio Diaz Diaz. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . +*/ + +class State + { + int st; + +public: + enum { states = 12 }; + State() : st( 0 ) {} + int operator()() const { return st; } + bool is_char() const { return st < 7; } + + void set_char() + { + static const int next[states] = { 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 4, 5 }; + st = next[st]; + } + bool is_char_set_char() { set_char(); return st < 4; } + void set_char_rep() { st = 8; } + void set_match() { st = ( st < 7 ) ? 7 : 10; } + void set_rep() { st = ( st < 7 ) ? 8 : 11; } + void set_short_rep() { st = ( st < 7 ) ? 9 : 11; } + }; + + +enum { + min_dictionary_bits = 12, + min_dictionary_size = 1 << min_dictionary_bits, // >= modeled_distances + max_dictionary_bits = 29, + max_dictionary_size = 1 << max_dictionary_bits, + min_member_size = 36, + literal_context_bits = 3, + literal_pos_state_bits = 0, // not used + pos_state_bits = 2, + pos_states = 1 << pos_state_bits, + pos_state_mask = pos_states - 1, + + len_states = 4, + dis_slot_bits = 6, + start_dis_model = 4, + end_dis_model = 14, + modeled_distances = 1 << ( end_dis_model / 2 ), // 128 + dis_align_bits = 4, + dis_align_size = 1 << dis_align_bits, + + len_low_bits = 3, + len_mid_bits = 3, + len_high_bits = 8, + len_low_symbols = 1 << len_low_bits, + len_mid_symbols = 1 << len_mid_bits, + len_high_symbols = 1 << len_high_bits, + max_len_symbols = len_low_symbols + len_mid_symbols + len_high_symbols, + + min_match_len = 2, // must be 2 + max_match_len = min_match_len + max_len_symbols - 1, // 273 + min_match_len_limit = 5 }; + +inline int get_len_state( const int len ) + { return std::min( len - min_match_len, len_states - 1 ); } + +inline int get_lit_state( const uint8_t prev_byte ) + { return prev_byte >> ( 8 - literal_context_bits ); } + + +enum { bit_model_move_bits = 5, + bit_model_total_bits = 11, + bit_model_total = 1 << bit_model_total_bits }; + +struct Bit_model + { + int probability; + void reset() { probability = bit_model_total / 2; } + void reset( const int size ) + { for( int i = 0; i < size; ++i ) this[i].reset(); } + Bit_model() { reset(); } + }; + +struct Len_model + { + Bit_model choice1; + Bit_model choice2; + Bit_model bm_low[pos_states][len_low_symbols]; + Bit_model bm_mid[pos_states][len_mid_symbols]; + Bit_model bm_high[len_high_symbols]; + + void reset() + { + choice1.reset(); + choice2.reset(); + bm_low[0][0].reset( pos_states * len_low_symbols ); + bm_mid[0][0].reset( pos_states * len_mid_symbols ); + bm_high[0].reset( len_high_symbols ); + } + }; + + +// defined in main.cc +extern int verbosity; + +class Pretty_print // requires global var 'int verbosity' + { + std::string name_; + std::string padded_name; + const char * const stdin_name; + unsigned longest_name; + mutable bool first_post; + +public: + Pretty_print( const std::vector< std::string > & filenames ) + : stdin_name( "(stdin)" ), longest_name( 0 ), first_post( false ) + { + if( verbosity <= 0 ) return; + const unsigned stdin_name_len = std::strlen( stdin_name ); + for( unsigned i = 0; i < filenames.size(); ++i ) + { + const std::string & s = filenames[i]; + const unsigned len = ( s == "-" ) ? stdin_name_len : s.size(); + if( longest_name < len ) longest_name = len; + } + if( longest_name == 0 ) longest_name = stdin_name_len; + } + + void set_name( const std::string & filename ) + { + if( filename.size() && filename != "-" ) name_ = filename; + else name_ = stdin_name; + padded_name = " "; padded_name += name_; padded_name += ": "; + if( longest_name > name_.size() ) + padded_name.append( longest_name - name_.size(), ' ' ); + first_post = true; + } + + void reset() const { if( name_.size() ) first_post = true; } + const char * name() const { return name_.c_str(); } + void operator()( const char * const msg = 0 ) const; + }; + + +class CRC32 + { + uint32_t data[256]; // Table of CRCs of all 8-bit messages. + +public: + CRC32() + { + for( unsigned n = 0; n < 256; ++n ) + { + unsigned c = n; + for( int k = 0; k < 8; ++k ) + { if( c & 1 ) c = 0xEDB88320U ^ ( c >> 1 ); else c >>= 1; } + data[n] = c; + } + } + + uint32_t operator[]( const uint8_t byte ) const { return data[byte]; } + + void update_byte( uint32_t & crc, const uint8_t byte ) const + { crc = data[(crc^byte)&0xFF] ^ ( crc >> 8 ); } + + // about as fast as it is possible without messing with endianness + void update_buf( uint32_t & crc, const uint8_t * const buffer, + const int size ) const + { + uint32_t c = crc; + for( int i = 0; i < size; ++i ) + c = data[(c^buffer[i])&0xFF] ^ ( c >> 8 ); + crc = c; + } + }; + +extern const CRC32 crc32; + + +inline bool isvalid_ds( const unsigned dictionary_size ) + { return dictionary_size >= min_dictionary_size && + dictionary_size <= max_dictionary_size; } + + +inline int real_bits( unsigned value ) + { + int bits = 0; + while( value > 0 ) { value >>= 1; ++bits; } + return bits; + } + + +const uint8_t lzip_magic[4] = { 0x4C, 0x5A, 0x49, 0x50 }; // "LZIP" + +struct Lzip_header + { + enum { size = 6 }; + uint8_t data[size]; // 0-3 magic bytes + // 4 version + // 5 coded dictionary size + + void set_magic() { std::memcpy( data, lzip_magic, 4 ); data[4] = 1; } + bool check_magic() const { return std::memcmp( data, lzip_magic, 4 ) == 0; } + + bool check_prefix( const int sz ) const // detect (truncated) header + { + for( int i = 0; i < sz && i < 4; ++i ) + if( data[i] != lzip_magic[i] ) return false; + return sz > 0; + } + + bool check_corrupt() const // detect corrupt header + { + int matches = 0; + for( int i = 0; i < 4; ++i ) + if( data[i] == lzip_magic[i] ) ++matches; + return matches > 1 && matches < 4; + } + + uint8_t version() const { return data[4]; } + bool check_version() const { return data[4] == 1; } + + unsigned dictionary_size() const + { + unsigned sz = 1 << ( data[5] & 0x1F ); + if( sz > min_dictionary_size ) + sz -= ( sz / 16 ) * ( ( data[5] >> 5 ) & 7 ); + return sz; + } + + bool dictionary_size( const unsigned sz ) + { + if( !isvalid_ds( sz ) ) return false; + data[5] = real_bits( sz - 1 ); + if( sz > min_dictionary_size ) + { + const unsigned base_size = 1 << data[5]; + const unsigned fraction = base_size / 16; + for( unsigned i = 7; i >= 1; --i ) + if( base_size - ( i * fraction ) >= sz ) + { data[5] |= i << 5; break; } + } + return true; + } + + bool check() const + { return check_magic() && check_version() && + isvalid_ds( dictionary_size() ); } + }; + + +struct Lzip_trailer + { + enum { size = 20 }; + uint8_t data[size]; // 0-3 CRC32 of the uncompressed data + // 4-11 size of the uncompressed data + // 12-19 member size including header and trailer + + unsigned data_crc() const + { + unsigned tmp = 0; + for( int i = 3; i >= 0; --i ) { tmp <<= 8; tmp += data[i]; } + return tmp; + } + + void data_crc( unsigned crc ) + { for( int i = 0; i <= 3; ++i ) { data[i] = (uint8_t)crc; crc >>= 8; } } + + unsigned long long data_size() const + { + unsigned long long tmp = 0; + for( int i = 11; i >= 4; --i ) { tmp <<= 8; tmp += data[i]; } + return tmp; + } + + void data_size( unsigned long long sz ) + { for( int i = 4; i <= 11; ++i ) { data[i] = (uint8_t)sz; sz >>= 8; } } + + unsigned long long member_size() const + { + unsigned long long tmp = 0; + for( int i = 19; i >= 12; --i ) { tmp <<= 8; tmp += data[i]; } + return tmp; + } + + void member_size( unsigned long long sz ) + { for( int i = 12; i <= 19; ++i ) { data[i] = (uint8_t)sz; sz >>= 8; } } + + bool check_consistency() const // check internal consistency + { + const unsigned crc = data_crc(); + const unsigned long long dsize = data_size(); + if( ( crc == 0 ) != ( dsize == 0 ) ) return false; + const unsigned long long msize = member_size(); + if( msize < min_member_size ) return false; + const unsigned long long mlimit = ( 9 * dsize + 7 ) / 8 + min_member_size; + if( mlimit > dsize && msize > mlimit ) return false; + const unsigned long long dlimit = 7090 * ( msize - 26 ) - 1; + if( dlimit > msize && dsize > dlimit ) return false; + return true; + } + }; + + +struct Cl_options // command-line options + { + bool ignore_empty; + bool ignore_marking; + bool ignore_trailing; + bool loose_trailing; + + Cl_options() + : ignore_empty( true ), ignore_marking( true ), + ignore_trailing( true ), loose_trailing( false ) {} + }; + + +struct Error + { + const char * const msg; + explicit Error( const char * const s ) : msg( s ) {} + }; + +inline void set_retval( int & retval, const int new_val ) + { if( retval < new_val ) retval = new_val; } + +const char * const bad_magic_msg = "Bad magic number (file not in lzip format)."; +const char * const bad_dict_msg = "Invalid dictionary size in member header."; +const char * const corrupt_mm_msg = "Corrupt header in multimember file."; +const char * const empty_msg = "Empty member not allowed."; +const char * const marking_msg = "Marking data not allowed."; +const char * const trailing_msg = "Trailing data not allowed."; + +// defined in decoder.cc +int readblock( const int fd, uint8_t * const buf, const int size ); +int writeblock( const int fd, const uint8_t * const buf, const int size ); + +// defined in list.cc +int list_files( const std::vector< std::string > & filenames, + const Cl_options & cl_opts ); + +// defined in main.cc +struct stat; +const char * bad_version( const unsigned version ); +const char * format_ds( const unsigned dictionary_size ); +void show_header( const unsigned dictionary_size ); +int open_instream( const char * const name, struct stat * const in_statsp, + const bool one_to_one, const bool reg_only = false ); +void show_error( const char * const msg, const int errcode = 0, + const bool help = false ); +void show_file_error( const char * const filename, const char * const msg, + const int errcode = 0 ); +void internal_error( const char * const msg ); +class Matchfinder_base; +void show_cprogress( const unsigned long long cfile_size = 0, + const unsigned long long partial_size = 0, + const Matchfinder_base * const m = 0, + const Pretty_print * const p = 0 ); +class Range_decoder; +void show_dprogress( const unsigned long long cfile_size = 0, + const unsigned long long partial_size = 0, + const Range_decoder * const d = 0, + const Pretty_print * const p = 0 ); diff --git a/lzip_index.cc b/lzip_index.cc new file mode 100644 index 0000000..6c1caf2 --- /dev/null +++ b/lzip_index.cc @@ -0,0 +1,218 @@ +/* Lzip - LZMA lossless data compressor + Copyright (C) 2008-2024 Antonio Diaz Diaz. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . +*/ + +#define _FILE_OFFSET_BITS 64 + +#include +#include +#include +#include +#include +#include +#include +#include + +#include "lzip.h" +#include "lzip_index.h" + + +namespace { + +int seek_read( const int fd, uint8_t * const buf, const int size, + const long long pos ) + { + if( lseek( fd, pos, SEEK_SET ) == pos ) + return readblock( fd, buf, size ); + return 0; + } + +} // end namespace + + +bool Lzip_index::check_header( const Lzip_header & header ) + { + if( !header.check_magic() ) + { error_ = bad_magic_msg; retval_ = 2; return false; } + if( !header.check_version() ) + { error_ = bad_version( header.version() ); retval_ = 2; return false; } + if( !isvalid_ds( header.dictionary_size() ) ) + { error_ = bad_dict_msg; retval_ = 2; return false; } + return true; + } + +void Lzip_index::set_errno_error( const char * const msg ) + { + error_ = msg; error_ += std::strerror( errno ); + retval_ = 1; + } + +void Lzip_index::set_num_error( const char * const msg, unsigned long long num ) + { + char buf[80]; + snprintf( buf, sizeof buf, "%s%llu", msg, num ); + error_ = buf; + retval_ = 2; + } + + +bool Lzip_index::read_header( const int fd, Lzip_header & header, + const long long pos, const bool ignore_marking ) + { + if( seek_read( fd, header.data, header.size, pos ) != header.size ) + { set_errno_error( "Error reading member header: " ); return false; } + uint8_t byte; + if( !ignore_marking && readblock( fd, &byte, 1 ) == 1 && byte != 0 ) + { error_ = marking_msg; retval_ = 2; return false; } + return true; + } + + +// If successful, push last member and set pos to member header. +bool Lzip_index::skip_trailing_data( const int fd, unsigned long long & pos, + const Cl_options & cl_opts ) + { + if( pos < min_member_size ) return false; + enum { block_size = 16384, + buffer_size = block_size + Lzip_trailer::size - 1 + Lzip_header::size }; + uint8_t buffer[buffer_size]; + int bsize = pos % block_size; // total bytes in buffer + if( bsize <= buffer_size - block_size ) bsize += block_size; + int search_size = bsize; // bytes to search for trailer + int rd_size = bsize; // bytes to read from file + unsigned long long ipos = pos - rd_size; // aligned to block_size + + while( true ) + { + if( seek_read( fd, buffer, rd_size, ipos ) != rd_size ) + { set_errno_error( "Error seeking member trailer: " ); return false; } + const uint8_t max_msb = ( ipos + search_size ) >> 56; + for( int i = search_size; i >= Lzip_trailer::size; --i ) + if( buffer[i-1] <= max_msb ) // most significant byte of member_size + { + const Lzip_trailer & trailer = + *(const Lzip_trailer *)( buffer + i - trailer.size ); + const unsigned long long member_size = trailer.member_size(); + if( member_size == 0 ) // skip trailing zeros + { while( i > trailer.size && buffer[i-9] == 0 ) --i; continue; } + if( member_size > ipos + i || !trailer.check_consistency() ) continue; + Lzip_header header; + if( !read_header( fd, header, ipos + i - member_size, + cl_opts.ignore_marking ) ) return false; + if( !header.check() ) continue; + const Lzip_header & header2 = *(const Lzip_header *)( buffer + i ); + const bool full_h2 = bsize - i >= header.size; + if( header2.check_prefix( bsize - i ) ) // last member + { + if( !full_h2 ) error_ = "Last member in input file is truncated."; + else if( check_header( header2 ) ) + error_ = "Last member in input file is truncated or corrupt."; + retval_ = 2; return false; + } + if( !cl_opts.loose_trailing && full_h2 && header2.check_corrupt() ) + { error_ = corrupt_mm_msg; retval_ = 2; return false; } + if( !cl_opts.ignore_trailing ) + { error_ = trailing_msg; retval_ = 2; return false; } + const unsigned long long data_size = trailer.data_size(); + if( !cl_opts.ignore_empty && data_size == 0 ) + { error_ = empty_msg; retval_ = 2; return false; } + pos = ipos + i - member_size; // good member + const unsigned dictionary_size = header.dictionary_size(); + if( dictionary_size_ < dictionary_size ) + dictionary_size_ = dictionary_size; + member_vector.push_back( Member( 0, data_size, pos, member_size, + dictionary_size ) ); + return true; + } + if( ipos == 0 ) + { set_num_error( "Bad trailer at pos ", pos - Lzip_trailer::size ); + return false; } + bsize = buffer_size; + search_size = bsize - Lzip_header::size; + rd_size = block_size; + ipos -= rd_size; + std::memcpy( buffer + rd_size, buffer, buffer_size - rd_size ); + } + } + + +Lzip_index::Lzip_index( const int infd, const Cl_options & cl_opts ) + : insize( lseek( infd, 0, SEEK_END ) ), retval_( 0 ), dictionary_size_( 0 ) + { + if( insize < 0 ) + { set_errno_error( "Input file is not seekable: " ); return; } + if( insize < min_member_size ) + { error_ = "Input file is too short."; retval_ = 2; return; } + if( insize > INT64_MAX ) + { error_ = "Input file is too long (2^63 bytes or more)."; + retval_ = 2; return; } + + Lzip_header header; + if( !read_header( infd, header, 0, cl_opts.ignore_marking ) || + !check_header( header ) ) return; + + unsigned long long pos = insize; // always points to a header or to EOF + while( pos >= min_member_size ) + { + Lzip_trailer trailer; + if( seek_read( infd, trailer.data, trailer.size, pos - trailer.size ) != + trailer.size ) + { set_errno_error( "Error reading member trailer: " ); break; } + const unsigned long long member_size = trailer.member_size(); + if( member_size > pos || !trailer.check_consistency() ) // bad trailer + { + if( member_vector.empty() ) + { if( skip_trailing_data( infd, pos, cl_opts ) ) continue; return; } + set_num_error( "Bad trailer at pos ", pos - trailer.size ); break; + } + if( !read_header( infd, header, pos - member_size, cl_opts.ignore_marking ) ) + break; + if( !header.check() ) // bad header + { + if( member_vector.empty() ) + { if( skip_trailing_data( infd, pos, cl_opts ) ) continue; return; } + set_num_error( "Bad header at pos ", pos - member_size ); break; + } + const unsigned long long data_size = trailer.data_size(); + if( !cl_opts.ignore_empty && data_size == 0 ) + { error_ = empty_msg; retval_ = 2; break; } + pos -= member_size; // good member + const unsigned dictionary_size = header.dictionary_size(); + if( dictionary_size_ < dictionary_size ) + dictionary_size_ = dictionary_size; + member_vector.push_back( Member( 0, data_size, pos, member_size, + dictionary_size ) ); + } + if( pos != 0 || member_vector.empty() || retval_ != 0 ) + { + member_vector.clear(); + if( retval_ == 0 ) { error_ = "Can't create file index."; retval_ = 2; } + return; + } + std::reverse( member_vector.begin(), member_vector.end() ); + for( unsigned long i = 0; ; ++i ) + { + const long long end = member_vector[i].dblock.end(); + if( end < 0 || end > INT64_MAX ) + { + member_vector.clear(); + error_ = "Data in input file is too long (2^63 bytes or more)."; + retval_ = 2; return; + } + if( i + 1 >= member_vector.size() ) break; + member_vector[i+1].dblock.pos( end ); + } + } diff --git a/lzip_index.h b/lzip_index.h new file mode 100644 index 0000000..928a7c7 --- /dev/null +++ b/lzip_index.h @@ -0,0 +1,93 @@ +/* Lzip - LZMA lossless data compressor + Copyright (C) 2008-2024 Antonio Diaz Diaz. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . +*/ + +#ifndef INT64_MAX +#define INT64_MAX 0x7FFFFFFFFFFFFFFFLL +#endif + + +class Block + { + long long pos_, size_; // pos >= 0, size >= 0, pos + size <= INT64_MAX + +public: + Block( const long long p, const long long s ) : pos_( p ), size_( s ) {} + + long long pos() const { return pos_; } + long long size() const { return size_; } + long long end() const { return pos_ + size_; } + + void pos( const long long p ) { pos_ = p; } + void size( const long long s ) { size_ = s; } + }; + + +class Lzip_index + { + struct Member + { + Block dblock, mblock; // data block, member block + unsigned dictionary_size; + + Member( const long long dpos, const long long dsize, + const long long mpos, const long long msize, + const unsigned dict_size ) + : dblock( dpos, dsize ), mblock( mpos, msize ), + dictionary_size( dict_size ) {} + }; + + std::vector< Member > member_vector; + std::string error_; + const long long insize; + int retval_; + unsigned dictionary_size_; // largest dictionary size in the file + + bool check_header( const Lzip_header & header ); + void set_errno_error( const char * const msg ); + void set_num_error( const char * const msg, unsigned long long num ); + bool read_header( const int fd, Lzip_header & header, const long long pos, + const bool ignore_marking ); + bool skip_trailing_data( const int fd, unsigned long long & pos, + const Cl_options & cl_opts ); + +public: + Lzip_index( const int infd, const Cl_options & cl_opts ); + + long members() const { return member_vector.size(); } + const std::string & error() const { return error_; } + int retval() const { return retval_; } + unsigned dictionary_size() const { return dictionary_size_; } + + long long udata_size() const + { if( member_vector.empty() ) return 0; + return member_vector.back().dblock.end(); } + + long long cdata_size() const + { if( member_vector.empty() ) return 0; + return member_vector.back().mblock.end(); } + + // total size including trailing data (if any) + long long file_size() const + { if( insize >= 0 ) return insize; else return 0; } + + const Block & dblock( const long i ) const + { return member_vector[i].dblock; } + const Block & mblock( const long i ) const + { return member_vector[i].mblock; } + unsigned dictionary_size( const long i ) const + { return member_vector[i].dictionary_size; } + }; diff --git a/main.cc b/main.cc new file mode 100644 index 0000000..ed0678b --- /dev/null +++ b/main.cc @@ -0,0 +1,1109 @@ +/* Lzip - LZMA lossless data compressor + Copyright (C) 2008-2024 Antonio Diaz Diaz. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . +*/ +/* + Exit status: 0 for a normal exit, 1 for environmental problems + (file not found, invalid command-line options, I/O errors, etc), 2 to + indicate a corrupt or invalid input file, 3 for an internal consistency + error (e.g., bug) which caused lzip to panic. +*/ + +#define _FILE_OFFSET_BITS 64 + +#include +#include +#include +#include // CHAR_BIT, SSIZE_MAX +#include +#include +#include +#include +#include +#include +#include +#include +#include // SIZE_MAX +#include +#include +#include +#if defined __MSVCRT__ || defined __OS2__ || defined __DJGPP__ +#include +#if defined __MSVCRT__ +#include +#define fchmod(x,y) 0 +#define fchown(x,y,z) 0 +#define mkdir(name,mode) _mkdir(name) +#define strtoull std::strtoul +#define SIGHUP SIGTERM +#define S_ISSOCK(x) 0 +#ifndef S_IRGRP +#define S_IRGRP 0 +#define S_IWGRP 0 +#define S_IROTH 0 +#define S_IWOTH 0 +#endif +#endif +#if defined __DJGPP__ +#define S_ISSOCK(x) 0 +#define S_ISVTX 0 +#endif +#endif + +#include "arg_parser.h" +#include "lzip.h" +#include "decoder.h" +#include "encoder_base.h" +#include "encoder.h" +#include "fast_encoder.h" + +#ifndef O_BINARY +#define O_BINARY 0 +#endif + +#if CHAR_BIT != 8 +#error "Environments where CHAR_BIT != 8 are not supported." +#endif + +#if ( defined SIZE_MAX && SIZE_MAX < UINT_MAX ) || \ + ( defined SSIZE_MAX && SSIZE_MAX < INT_MAX ) +#error "Environments where 'size_t' is narrower than 'int' are not supported." +#endif + +int verbosity = 0; + +namespace { + +const char * const program_name = "lzip"; +const char * const program_year = "2024"; +const char * invocation_name = program_name; // default value + +const struct { const char * from; const char * to; } known_extensions[] = { + { ".lz", "" }, + { ".tlz", ".tar" }, + { 0, 0 } }; + +struct Lzma_options + { + int dictionary_size; // 4 KiB .. 512 MiB + int match_len_limit; // 5 .. 273 + }; + +enum Mode { m_compress, m_decompress, m_list, m_test }; + +/* Variables used in signal handler context. + They are not declared volatile because the handler never returns. */ +std::string output_filename; +int outfd = -1; +bool delete_output_on_interrupt = false; + + +void show_help() + { + std::printf( "Lzip is a lossless data compressor with a user interface similar to the one\n" + "of gzip or bzip2. Lzip uses a simplified form of the 'Lempel-Ziv-Markov\n" + "chain-Algorithm' (LZMA) stream format to maximize interoperability. The\n" + "maximum dictionary size is 512 MiB so that any lzip file can be decompressed\n" + "on 32-bit machines. Lzip provides accurate and robust 3-factor integrity\n" + "checking. Lzip can compress about as fast as gzip (lzip -0) or compress most\n" + "files more than bzip2 (lzip -9). Decompression speed is intermediate between\n" + "gzip and bzip2. Lzip is better than gzip and bzip2 from a data recovery\n" + "perspective. Lzip has been designed, written, and tested with great care to\n" + "replace gzip and bzip2 as the standard general-purpose compressed format for\n" + "Unix-like systems.\n" + "\nUsage: %s [options] [files]\n", invocation_name ); + std::printf( "\nOptions:\n" + " -h, --help display this help and exit\n" + " -V, --version output version information and exit\n" + " -a, --trailing-error exit with error status if trailing data\n" + " -b, --member-size= set member size limit in bytes\n" + " -c, --stdout write to standard output, keep input files\n" + " -d, --decompress decompress, test compressed file integrity\n" + " -f, --force overwrite existing output files\n" + " -F, --recompress force re-compression of compressed files\n" + " -k, --keep keep (don't delete) input files\n" + " -l, --list print (un)compressed file sizes\n" + " -m, --match-length= set match length limit in bytes [36]\n" + " -o, --output= write to , keep input files\n" + " -q, --quiet suppress all messages\n" + " -s, --dictionary-size= set dictionary size limit in bytes [8 MiB]\n" + " -S, --volume-size= set volume size limit in bytes\n" + " -t, --test test compressed file integrity\n" + " -v, --verbose be verbose (a 2nd -v gives more)\n" + " -0 .. -9 set compression level [default 6]\n" + " --fast alias for -0\n" + " --best alias for -9\n" + " --empty-error exit with error status if empty member in file\n" + " --marking-error exit with error status if 1st LZMA byte not 0\n" + " --loose-trailing allow trailing data seeming corrupt header\n" + "\nIf no file names are given, or if a file is '-', lzip compresses or\n" + "decompresses from standard input to standard output.\n" + "Numbers may be followed by a multiplier: k = kB = 10^3 = 1000,\n" + "Ki = KiB = 2^10 = 1024, M = 10^6, Mi = 2^20, G = 10^9, Gi = 2^30, etc...\n" + "Dictionary sizes 12 to 29 are interpreted as powers of two, meaning 2^12 to\n" + "2^29 bytes.\n" + "\nThe bidimensional parameter space of LZMA can't be mapped to a linear scale\n" + "optimal for all files. If your files are large, very repetitive, etc, you\n" + "may need to use the options --dictionary-size and --match-length directly\n" + "to achieve optimal performance.\n" + "\nTo extract all the files from archive 'foo.tar.lz', use the commands\n" + "'tar -xf foo.tar.lz' or 'lzip -cd foo.tar.lz | tar -xf -'.\n" + "\nExit status: 0 for a normal exit, 1 for environmental problems\n" + "(file not found, invalid command-line options, I/O errors, etc), 2 to\n" + "indicate a corrupt or invalid input file, 3 for an internal consistency\n" + "error (e.g., bug) which caused lzip to panic.\n" + "\nThe ideas embodied in lzip are due to (at least) the following people:\n" + "Abraham Lempel and Jacob Ziv (for the LZ algorithm), Andrei Markov (for the\n" + "definition of Markov chains), G.N.N. Martin (for the definition of range\n" + "encoding), Igor Pavlov (for putting all the above together in LZMA), and\n" + "Julian Seward (for bzip2's CLI).\n" + "\nReport bugs to lzip-bug@nongnu.org\n" + "Lzip home page: http://www.nongnu.org/lzip/lzip.html\n" ); + } + + +void show_version() + { + std::printf( "%s %s\n", program_name, PROGVERSION ); + std::printf( "Copyright (C) %s Antonio Diaz Diaz.\n", program_year ); + std::printf( "License GPLv2+: GNU GPL version 2 or later \n" + "This is free software: you are free to change and redistribute it.\n" + "There is NO WARRANTY, to the extent permitted by law.\n" ); + } + +} // end namespace + +void Pretty_print::operator()( const char * const msg ) const + { + if( verbosity < 0 ) return; + if( first_post ) + { + first_post = false; + std::fputs( padded_name.c_str(), stderr ); + if( !msg ) std::fflush( stderr ); + } + if( msg ) std::fprintf( stderr, "%s\n", msg ); + } + + +const char * bad_version( const unsigned version ) + { + static char buf[80]; + snprintf( buf, sizeof buf, "Version %u member format not supported.", + version ); + return buf; + } + + +const char * format_ds( const unsigned dictionary_size ) + { + enum { bufsize = 16, factor = 1024, n = 3 }; + static char buf[bufsize]; + const char * const prefix[n] = { "Ki", "Mi", "Gi" }; + const char * p = ""; + const char * np = " "; + unsigned num = dictionary_size; + bool exact = ( num % factor == 0 ); + + for( int i = 0; i < n && ( num > 9999 || ( exact && num >= factor ) ); ++i ) + { num /= factor; if( num % factor != 0 ) exact = false; + p = prefix[i]; np = ""; } + snprintf( buf, bufsize, "%s%4u %sB", np, num, p ); + return buf; + } + + +void show_header( const unsigned dictionary_size ) + { + std::fprintf( stderr, "dict %s, ", format_ds( dictionary_size ) ); + } + +namespace { + +// separate numbers of 5 or more digits in groups of 3 digits using '_' +const char * format_num3( unsigned long long num ) + { + enum { buffers = 8, bufsize = 4 * sizeof num, n = 10 }; + const char * const si_prefix = "kMGTPEZYRQ"; + const char * const binary_prefix = "KMGTPEZYRQ"; + static char buffer[buffers][bufsize]; // circle of static buffers for printf + static int current = 0; + + char * const buf = buffer[current++]; current %= buffers; + char * p = buf + bufsize - 1; // fill the buffer backwards + *p = 0; // terminator + if( num > 1024 ) + { + char prefix = 0; // try binary first, then si + for( int i = 0; i < n && num != 0 && num % 1024 == 0; ++i ) + { num /= 1024; prefix = binary_prefix[i]; } + if( prefix ) *(--p) = 'i'; + else + for( int i = 0; i < n && num != 0 && num % 1000 == 0; ++i ) + { num /= 1000; prefix = si_prefix[i]; } + if( prefix ) *(--p) = prefix; + } + const bool split = num >= 10000; + + for( int i = 0; ; ) + { + *(--p) = num % 10 + '0'; num /= 10; if( num == 0 ) break; + if( split && ++i >= 3 ) { i = 0; *(--p) = '_'; } + } + return p; + } + + +void show_option_error( const char * const arg, const char * const msg, + const char * const option_name ) + { + if( verbosity >= 0 ) + std::fprintf( stderr, "%s: '%s': %s option '%s'.\n", + program_name, arg, msg, option_name ); + } + + +// Recognized formats: k, Ki, [MGTPEZYRQ][i] +unsigned long long getnum( const char * const arg, + const char * const option_name, + const unsigned long long llimit, + const unsigned long long ulimit ) + { + char * tail; + errno = 0; + unsigned long long result = strtoull( arg, &tail, 0 ); + if( tail == arg ) + { show_option_error( arg, "Bad or missing numerical argument in", + option_name ); std::exit( 1 ); } + + if( !errno && tail[0] ) + { + const unsigned factor = ( tail[1] == 'i' ) ? 1024 : 1000; + int exponent = 0; // 0 = bad multiplier + switch( tail[0] ) + { + case 'Q': exponent = 10; break; + case 'R': exponent = 9; break; + case 'Y': exponent = 8; break; + case 'Z': exponent = 7; break; + case 'E': exponent = 6; break; + case 'P': exponent = 5; break; + case 'T': exponent = 4; break; + case 'G': exponent = 3; break; + case 'M': exponent = 2; break; + case 'K': if( factor == 1024 ) exponent = 1; break; + case 'k': if( factor == 1000 ) exponent = 1; break; + } + if( exponent <= 0 ) + { show_option_error( arg, "Bad multiplier in numerical argument of", + option_name ); std::exit( 1 ); } + for( int i = 0; i < exponent; ++i ) + { + if( ulimit / factor >= result ) result *= factor; + else { errno = ERANGE; break; } + } + } + if( !errno && ( result < llimit || result > ulimit ) ) errno = ERANGE; + if( errno ) + { + if( verbosity >= 0 ) + std::fprintf( stderr, "%s: '%s': Value out of limits [%s,%s] in " + "option '%s'.\n", program_name, arg, format_num3( llimit ), + format_num3( ulimit ), option_name ); + std::exit( 1 ); + } + return result; + } + + +int get_dict_size( const char * const arg, const char * const option_name ) + { + char * tail; + const long bits = std::strtol( arg, &tail, 0 ); + if( bits >= min_dictionary_bits && + bits <= max_dictionary_bits && *tail == 0 ) + return 1 << bits; + return getnum( arg, option_name, min_dictionary_size, max_dictionary_size ); + } + + +void set_mode( Mode & program_mode, const Mode new_mode ) + { + if( program_mode != m_compress && program_mode != new_mode ) + { + show_error( "Only one operation can be specified.", 0, true ); + std::exit( 1 ); + } + program_mode = new_mode; + } + + +int extension_index( const std::string & name ) + { + for( int eindex = 0; known_extensions[eindex].from; ++eindex ) + { + const std::string ext( known_extensions[eindex].from ); + if( name.size() > ext.size() && + name.compare( name.size() - ext.size(), ext.size(), ext ) == 0 ) + return eindex; + } + return -1; + } + + +void set_c_outname( const std::string & name, const bool filenames_given, + const bool force_ext, const bool multifile ) + { + /* zupdate < 1.9 depends on lzip adding the extension '.lz' to name when + reading from standard input. */ + output_filename = name; + if( multifile ) output_filename += "00001"; + if( force_ext || multifile || + ( !filenames_given && extension_index( output_filename ) < 0 ) ) + output_filename += known_extensions[0].from; + } + + +void set_d_outname( const std::string & name, const int eindex ) + { + if( eindex >= 0 ) + { + const std::string from( known_extensions[eindex].from ); + if( name.size() > from.size() ) + { + output_filename.assign( name, 0, name.size() - from.size() ); + output_filename += known_extensions[eindex].to; + return; + } + } + output_filename = name; output_filename += ".out"; + if( verbosity >= 1 ) + std::fprintf( stderr, "%s: %s: Can't guess original name -- using '%s'\n", + program_name, name.c_str(), output_filename.c_str() ); + } + +} // end namespace + +int open_instream( const char * const name, struct stat * const in_statsp, + const bool one_to_one, const bool reg_only ) + { + int infd = open( name, O_RDONLY | O_BINARY ); + if( infd < 0 ) + show_file_error( name, "Can't open input file", errno ); + else + { + const int i = fstat( infd, in_statsp ); + const mode_t mode = in_statsp->st_mode; + const bool can_read = ( i == 0 && !reg_only && + ( S_ISBLK( mode ) || S_ISCHR( mode ) || + S_ISFIFO( mode ) || S_ISSOCK( mode ) ) ); + if( i != 0 || ( !S_ISREG( mode ) && ( !can_read || one_to_one ) ) ) + { + if( verbosity >= 0 ) + std::fprintf( stderr, "%s: %s: Input file is not a regular file%s.\n", + program_name, name, ( can_read && one_to_one ) ? + ",\n and neither '-c' nor '-o' were specified" : "" ); + close( infd ); + infd = -1; + } + } + return infd; + } + +namespace { + +int open_instream2( const char * const name, struct stat * const in_statsp, + const Mode program_mode, const int eindex, + const bool one_to_one, const bool recompress ) + { + if( program_mode == m_compress && !recompress && eindex >= 0 ) + { + if( verbosity >= 0 ) + std::fprintf( stderr, "%s: %s: Input file already has '%s' suffix.\n", + program_name, name, known_extensions[eindex].from ); + return -1; + } + return open_instream( name, in_statsp, one_to_one, false ); + } + + +bool make_dirs( const std::string & name ) + { + int i = name.size(); + while( i > 0 && name[i-1] != '/' ) --i; // remove last component + while( i > 0 && name[i-1] == '/' ) --i; // remove slash(es) + const int dirsize = i; // size of dirname without trailing slash(es) + + for( i = 0; i < dirsize; ) // if dirsize == 0, dirname is '/' or empty + { + while( i < dirsize && name[i] == '/' ) ++i; + const int first = i; + while( i < dirsize && name[i] != '/' ) ++i; + if( first < i ) + { + const std::string partial( name, 0, i ); + const mode_t mode = S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH; + struct stat st; + if( stat( partial.c_str(), &st ) == 0 ) + { if( !S_ISDIR( st.st_mode ) ) { errno = ENOTDIR; return false; } } + else if( mkdir( partial.c_str(), mode ) != 0 && errno != EEXIST ) + return false; // if EEXIST, another process created the dir + } + } + return true; + } + + +bool open_outstream( const bool force, const bool protect ) + { + const mode_t usr_rw = S_IRUSR | S_IWUSR; + const mode_t all_rw = usr_rw | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH; + const mode_t outfd_mode = protect ? usr_rw : all_rw; + int flags = O_CREAT | O_WRONLY | O_BINARY; + if( force ) flags |= O_TRUNC; else flags |= O_EXCL; + + outfd = -1; + if( output_filename.size() && + output_filename[output_filename.size()-1] == '/' ) errno = EISDIR; + else { + if( !protect && !make_dirs( output_filename ) ) + { show_file_error( output_filename.c_str(), + "Error creating intermediate directory", errno ); return false; } + outfd = open( output_filename.c_str(), flags, outfd_mode ); + if( outfd >= 0 ) { delete_output_on_interrupt = true; return true; } + if( errno == EEXIST ) + { show_file_error( output_filename.c_str(), + "Output file already exists, skipping." ); return false; } + } + show_file_error( output_filename.c_str(), "Can't create output file", errno ); + return false; + } + + +void set_signals( void (*action)(int) ) + { + std::signal( SIGHUP, action ); + std::signal( SIGINT, action ); + std::signal( SIGTERM, action ); + } + + +void cleanup_and_fail( const int retval ) + { + set_signals( SIG_IGN ); // ignore signals + if( delete_output_on_interrupt ) + { + delete_output_on_interrupt = false; + show_file_error( output_filename.c_str(), + "Deleting output file, if it exists." ); + if( outfd >= 0 ) { close( outfd ); outfd = -1; } + if( std::remove( output_filename.c_str() ) != 0 && errno != ENOENT ) + show_error( "warning: deletion of output file failed", errno ); + } + std::exit( retval ); + } + + +extern "C" void signal_handler( int ) + { + show_error( "Control-C or similar caught, quitting." ); + cleanup_and_fail( 1 ); + } + + +bool check_tty_in( const char * const input_filename, const int infd, + const Mode program_mode, int & retval ) + { + if( ( program_mode == m_decompress || program_mode == m_test ) && + isatty( infd ) ) // for example /dev/tty + { show_file_error( input_filename, + "I won't read compressed data from a terminal." ); + close( infd ); set_retval( retval, 2 ); + if( program_mode != m_test ) cleanup_and_fail( retval ); + return false; } + return true; + } + +bool check_tty_out( const Mode program_mode ) + { + if( program_mode == m_compress && isatty( outfd ) ) + { show_file_error( output_filename.size() ? + output_filename.c_str() : "(stdout)", + "I won't write compressed data to a terminal." ); + return false; } + return true; + } + + +// Set permissions, owner, and times. +void close_and_set_permissions( const struct stat * const in_statsp ) + { + bool warning = false; + if( in_statsp ) + { + const mode_t mode = in_statsp->st_mode; + // fchown in many cases returns with EPERM, which can be safely ignored. + if( fchown( outfd, in_statsp->st_uid, in_statsp->st_gid ) == 0 ) + { if( fchmod( outfd, mode ) != 0 ) warning = true; } + else + if( errno != EPERM || + fchmod( outfd, mode & ~( S_ISUID | S_ISGID | S_ISVTX ) ) != 0 ) + warning = true; + } + if( close( outfd ) != 0 ) + { show_file_error( output_filename.c_str(), "Error closing output file", + errno ); cleanup_and_fail( 1 ); } + outfd = -1; + delete_output_on_interrupt = false; + if( in_statsp ) + { + struct utimbuf t; + t.actime = in_statsp->st_atime; + t.modtime = in_statsp->st_mtime; + if( utime( output_filename.c_str(), &t ) != 0 ) warning = true; + } + if( warning && verbosity >= 1 ) + show_file_error( output_filename.c_str(), + "warning: can't change output file attributes", errno ); + } + + +bool next_filename() + { + const unsigned name_len = output_filename.size(); + const unsigned ext_len = std::strlen( known_extensions[0].from ); + if( name_len >= ext_len + 5 ) // "*00001.lz" + for( int i = name_len - ext_len - 1, j = 0; j < 5; --i, ++j ) + { + if( output_filename[i] < '9' ) { ++output_filename[i]; return true; } + else output_filename[i] = '0'; + } + return false; + } + + +int compress( const unsigned long long cfile_size, + const unsigned long long member_size, + const unsigned long long volume_size, const int infd, + const Lzma_options & encoder_options, const Pretty_print & pp, + const struct stat * const in_statsp, const bool zero ) + { + int retval = 0; + LZ_encoder_base * encoder = 0; // polymorphic encoder + if( verbosity >= 1 ) pp(); + + if( zero ) + encoder = new FLZ_encoder( infd, outfd ); + else + { + Lzip_header header; + if( header.dictionary_size( encoder_options.dictionary_size ) && + encoder_options.match_len_limit >= min_match_len_limit && + encoder_options.match_len_limit <= max_match_len ) + encoder = new LZ_encoder( header.dictionary_size(), + encoder_options.match_len_limit, infd, outfd ); + else internal_error( "invalid argument to encoder." ); + } + + unsigned long long in_size = 0, out_size = 0, partial_volume_size = 0; + while( true ) // encode one member per iteration + { + const unsigned long long size = ( volume_size > 0 ) ? + std::min( member_size, volume_size - partial_volume_size ) : member_size; + show_cprogress( cfile_size, in_size, encoder, &pp ); // init + if( !encoder->encode_member( size ) ) + { pp( "Encoder error." ); retval = 1; break; } + in_size += encoder->data_position(); + out_size += encoder->member_position(); + if( encoder->data_finished() ) break; + if( volume_size > 0 ) + { + partial_volume_size += encoder->member_position(); + if( partial_volume_size >= volume_size - min_dictionary_size ) + { + partial_volume_size = 0; + if( delete_output_on_interrupt ) + { + close_and_set_permissions( in_statsp ); + if( !next_filename() ) + { pp( "Too many volume files." ); retval = 1; break; } + if( !open_outstream( true, in_statsp ) ) { retval = 1; break; } + } + } + } + encoder->reset(); + } + + if( retval == 0 && verbosity >= 1 ) + { + if( in_size == 0 || out_size == 0 ) + std::fputs( " no data compressed.\n", stderr ); + else + std::fprintf( stderr, "%6.3f:1, %5.2f%% ratio, %5.2f%% saved, " + "%llu in, %llu out.\n", + (double)in_size / out_size, + ( 100.0 * out_size ) / in_size, + 100.0 - ( ( 100.0 * out_size ) / in_size ), + in_size, out_size ); + } + delete encoder; + return retval; + } + + +unsigned char xdigit( const unsigned value ) // hex digit for 'value' + { + if( value <= 9 ) return '0' + value; + if( value <= 15 ) return 'A' + value - 10; + return 0; + } + + +bool show_trailing_data( const uint8_t * const data, const int size, + const Pretty_print & pp, const bool all, + const int ignore_trailing ) // -1 = show + { + if( verbosity >= 4 || ignore_trailing <= 0 ) + { + std::string msg; + if( !all ) msg = "first bytes of "; + msg += "trailing data = "; + for( int i = 0; i < size; ++i ) + { + msg += xdigit( data[i] >> 4 ); + msg += xdigit( data[i] & 0x0F ); + msg += ' '; + } + msg += '\''; + for( int i = 0; i < size; ++i ) + { if( std::isprint( data[i] ) ) msg += data[i]; else msg += '.'; } + msg += '\''; + pp( msg.c_str() ); + if( ignore_trailing == 0 ) show_file_error( pp.name(), trailing_msg ); + } + return ignore_trailing > 0; + } + + +int decompress( const unsigned long long cfile_size, const int infd, + const Cl_options & cl_opts, const Pretty_print & pp, + const bool testing ) + { + unsigned long long partial_file_pos = 0; + Range_decoder rdec( infd ); + int retval = 0; + + for( bool first_member = true; ; first_member = false ) + { + Lzip_header header; + rdec.reset_member_position(); + const int size = rdec.read_data( header.data, header.size ); + if( rdec.finished() ) // End Of File + { + if( first_member ) + { show_file_error( pp.name(), "File ends unexpectedly at member header." ); + retval = 2; } + else if( header.check_prefix( size ) ) + { pp( "Truncated header in multimember file." ); + show_trailing_data( header.data, size, pp, true, -1 ); retval = 2; } + else if( size > 0 && !show_trailing_data( header.data, size, pp, true, + cl_opts.ignore_trailing ) ) retval = 2; + break; + } + if( !header.check_magic() ) + { + if( first_member ) + { show_file_error( pp.name(), bad_magic_msg ); retval = 2; } + else if( !cl_opts.loose_trailing && header.check_corrupt() ) + { pp( corrupt_mm_msg ); + show_trailing_data( header.data, size, pp, false, -1 ); retval = 2; } + else if( !show_trailing_data( header.data, size, pp, false, + cl_opts.ignore_trailing ) ) retval = 2; + break; + } + if( !header.check_version() ) + { pp( bad_version( header.version() ) ); retval = 2; break; } + const unsigned dictionary_size = header.dictionary_size(); + if( !isvalid_ds( dictionary_size ) ) + { pp( bad_dict_msg ); retval = 2; break; } + + if( verbosity >= 2 || ( verbosity == 1 && first_member ) ) pp(); + + LZ_decoder decoder( rdec, dictionary_size, outfd ); + show_dprogress( cfile_size, partial_file_pos, &rdec, &pp ); // init + const int result = decoder.decode_member( cl_opts, pp ); + partial_file_pos += rdec.member_position(); + if( result != 0 ) + { + if( verbosity >= 0 && result <= 2 ) + { + pp(); + std::fprintf( stderr, "%s at pos %llu\n", ( result == 2 ) ? + "File ends unexpectedly" : "Decoder error", + partial_file_pos ); + } + else if( result == 5 ) pp( empty_msg ); + else if( result == 6 ) pp( marking_msg ); + retval = 2; break; + } + if( verbosity >= 2 ) + { std::fputs( testing ? "ok\n" : "done\n", stderr ); pp.reset(); } + } + if( verbosity == 1 && retval == 0 ) + std::fputs( testing ? "ok\n" : "done\n", stderr ); + return retval; + } + +} // end namespace + + +void show_error( const char * const msg, const int errcode, const bool help ) + { + if( verbosity < 0 ) return; + if( msg && msg[0] ) + std::fprintf( stderr, "%s: %s%s%s\n", program_name, msg, + ( errcode > 0 ) ? ": " : "", + ( errcode > 0 ) ? std::strerror( errcode ) : "" ); + if( help ) + std::fprintf( stderr, "Try '%s --help' for more information.\n", + invocation_name ); + } + + +void show_file_error( const char * const filename, const char * const msg, + const int errcode ) + { + if( verbosity >= 0 ) + std::fprintf( stderr, "%s: %s: %s%s%s\n", program_name, filename, msg, + ( errcode > 0 ) ? ": " : "", + ( errcode > 0 ) ? std::strerror( errcode ) : "" ); + } + + +void internal_error( const char * const msg ) + { + if( verbosity >= 0 ) + std::fprintf( stderr, "%s: internal error: %s\n", program_name, msg ); + std::exit( 3 ); + } + + +void show_cprogress( const unsigned long long cfile_size, + const unsigned long long partial_size, + const Matchfinder_base * const m, + const Pretty_print * const p ) + { + static unsigned long long csize = 0; // file_size / 100 + static unsigned long long psize = 0; + static const Matchfinder_base * mb = 0; + static const Pretty_print * pp = 0; + static bool enabled = true; + + if( !enabled ) return; + if( p ) // initialize static vars + { + if( verbosity < 2 || !isatty( STDERR_FILENO ) ) { enabled = false; return; } + csize = cfile_size; psize = partial_size; mb = m; pp = p; + } + if( mb && pp ) + { + const unsigned long long pos = psize + mb->data_position(); + if( csize > 0 ) + std::fprintf( stderr, "%4llu%% %.1f MB\r", pos / csize, pos / 1000000.0 ); + else + std::fprintf( stderr, " %.1f MB\r", pos / 1000000.0 ); + pp->reset(); (*pp)(); // restore cursor position + } + } + + +void show_dprogress( const unsigned long long cfile_size, + const unsigned long long partial_size, + const Range_decoder * const d, + const Pretty_print * const p ) + { + static unsigned long long csize = 0; // file_size / 100 + static unsigned long long psize = 0; + static const Range_decoder * rdec = 0; + static const Pretty_print * pp = 0; + static int counter = 0; + static bool enabled = true; + + if( !enabled ) return; + if( p ) // initialize static vars + { + if( verbosity < 2 || !isatty( STDERR_FILENO ) ) { enabled = false; return; } + csize = cfile_size; psize = partial_size; rdec = d; pp = p; counter = 0; + } + if( rdec && pp && --counter <= 0 ) + { + const unsigned long long pos = psize + rdec->member_position(); + counter = 7; // update display every 114688 bytes + if( csize > 0 ) + std::fprintf( stderr, "%4llu%% %.1f MB\r", pos / csize, pos / 1000000.0 ); + else + std::fprintf( stderr, " %.1f MB\r", pos / 1000000.0 ); + pp->reset(); (*pp)(); // restore cursor position + } + } + + +int main( const int argc, const char * const argv[] ) + { + /* Mapping from gzip/bzip2 style 0..9 compression levels to the + corresponding LZMA compression parameters. */ + const Lzma_options option_mapping[] = + { + { 1 << 16, 16 }, // -0 + { 1 << 20, 5 }, // -1 + { 3 << 19, 6 }, // -2 + { 1 << 21, 8 }, // -3 + { 3 << 20, 12 }, // -4 + { 1 << 22, 20 }, // -5 + { 1 << 23, 36 }, // -6 + { 1 << 24, 68 }, // -7 + { 3 << 23, 132 }, // -8 + { 1 << 25, 273 } }; // -9 + Lzma_options encoder_options = option_mapping[6]; // default = "-6" + const unsigned long long max_member_size = 0x0008000000000000ULL; // 2 PiB + const unsigned long long max_volume_size = 0x4000000000000000ULL; // 4 EiB + unsigned long long member_size = max_member_size; + unsigned long long volume_size = 0; + std::string default_output_filename; + Mode program_mode = m_compress; + Cl_options cl_opts; // command-line options + bool force = false; + bool keep_input_files = false; + bool recompress = false; + bool to_stdout = false; + bool zero = false; + if( argc > 0 ) invocation_name = argv[0]; + + enum { opt_eer = 256, opt_lt, opt_mer }; + const Arg_parser::Option options[] = + { + { '0', "fast", Arg_parser::no }, + { '1', 0, Arg_parser::no }, + { '2', 0, Arg_parser::no }, + { '3', 0, Arg_parser::no }, + { '4', 0, Arg_parser::no }, + { '5', 0, Arg_parser::no }, + { '6', 0, Arg_parser::no }, + { '7', 0, Arg_parser::no }, + { '8', 0, Arg_parser::no }, + { '9', "best", Arg_parser::no }, + { 'a', "trailing-error", Arg_parser::no }, + { 'b', "member-size", Arg_parser::yes }, + { 'c', "stdout", Arg_parser::no }, + { 'd', "decompress", Arg_parser::no }, + { 'f', "force", Arg_parser::no }, + { 'F', "recompress", Arg_parser::no }, + { 'h', "help", Arg_parser::no }, + { 'k', "keep", Arg_parser::no }, + { 'l', "list", Arg_parser::no }, + { 'm', "match-length", Arg_parser::yes }, + { 'n', "threads", Arg_parser::yes }, + { 'o', "output", Arg_parser::yes }, + { 'q', "quiet", Arg_parser::no }, + { 's', "dictionary-size", Arg_parser::yes }, + { 'S', "volume-size", Arg_parser::yes }, + { 't', "test", Arg_parser::no }, + { 'v', "verbose", Arg_parser::no }, + { 'V', "version", Arg_parser::no }, + { opt_eer, "empty-error", Arg_parser::no }, + { opt_lt, "loose-trailing", Arg_parser::no }, + { opt_mer, "marking-error", Arg_parser::no }, + { 0, 0, Arg_parser::no } }; + + const Arg_parser parser( argc, argv, options ); + if( parser.error().size() ) // bad option + { show_error( parser.error().c_str(), 0, true ); return 1; } + + int argind = 0; + for( ; argind < parser.arguments(); ++argind ) + { + const int code = parser.code( argind ); + if( !code ) break; // no more options + const char * const pn = parser.parsed_name( argind ).c_str(); + const std::string & sarg = parser.argument( argind ); + const char * const arg = sarg.c_str(); + switch( code ) + { + case '0': case '1': case '2': case '3': case '4': + case '5': case '6': case '7': case '8': case '9': + zero = ( code == '0' ); + encoder_options = option_mapping[code-'0']; break; + case 'a': cl_opts.ignore_trailing = false; break; + case 'b': member_size = getnum( arg, pn, 100000, max_member_size ); break; + case 'c': to_stdout = true; break; + case 'd': set_mode( program_mode, m_decompress ); break; + case 'f': force = true; break; + case 'F': recompress = true; break; + case 'h': show_help(); return 0; + case 'k': keep_input_files = true; break; + case 'l': set_mode( program_mode, m_list ); break; + case 'm': encoder_options.match_len_limit = + getnum( arg, pn, min_match_len_limit, max_match_len ); + zero = false; break; + case 'n': break; + case 'o': if( sarg == "-" ) to_stdout = true; + else { default_output_filename = sarg; } break; + case 'q': verbosity = -1; break; + case 's': encoder_options.dictionary_size = get_dict_size( arg, pn ); + zero = false; break; + case 'S': volume_size = getnum( arg, pn, 100000, max_volume_size ); break; + case 't': set_mode( program_mode, m_test ); break; + case 'v': if( verbosity < 4 ) ++verbosity; break; + case 'V': show_version(); return 0; + case opt_eer: cl_opts.ignore_empty = false; break; + case opt_lt: cl_opts.loose_trailing = true; break; + case opt_mer: cl_opts.ignore_marking = false; break; + default: internal_error( "uncaught option." ); + } + } // end process options + +#if defined __MSVCRT__ || defined __OS2__ || defined __DJGPP__ + setmode( STDIN_FILENO, O_BINARY ); + setmode( STDOUT_FILENO, O_BINARY ); +#endif + + std::vector< std::string > filenames; + bool filenames_given = false; + for( ; argind < parser.arguments(); ++argind ) + { + filenames.push_back( parser.argument( argind ) ); + if( filenames.back() != "-" ) filenames_given = true; + } + if( filenames.empty() ) filenames.push_back("-"); + + if( program_mode == m_list ) return list_files( filenames, cl_opts ); + + if( program_mode == m_compress ) + { + if( volume_size > 0 && !to_stdout && default_output_filename.size() && + filenames.size() > 1 ) + { show_error( "Only can compress one file when using '-o' and '-S'.", + 0, true ); return 1; } + dis_slots.init(); + prob_prices.init(); + } + else volume_size = 0; + if( program_mode == m_test ) to_stdout = false; // apply overrides + if( program_mode == m_test || to_stdout ) default_output_filename.clear(); + + if( to_stdout && program_mode != m_test ) // check tty only once + { outfd = STDOUT_FILENO; if( !check_tty_out( program_mode ) ) return 1; } + else outfd = -1; + + const bool to_file = !to_stdout && program_mode != m_test && + default_output_filename.size(); + if( !to_stdout && program_mode != m_test && ( filenames_given || to_file ) ) + set_signals( signal_handler ); + + Pretty_print pp( filenames ); + + int failed_tests = 0; + int retval = 0; + const bool one_to_one = !to_stdout && program_mode != m_test && !to_file; + bool stdin_used = false; + struct stat in_stats; + for( unsigned i = 0; i < filenames.size(); ++i ) + { + std::string input_filename; + int infd; + + pp.set_name( filenames[i] ); + if( filenames[i] == "-" ) + { + if( stdin_used ) continue; else stdin_used = true; + infd = STDIN_FILENO; + if( !check_tty_in( pp.name(), infd, program_mode, retval ) ) continue; + if( one_to_one ) { outfd = STDOUT_FILENO; output_filename.clear(); } + } + else + { + const int eindex = extension_index( input_filename = filenames[i] ); + infd = open_instream2( input_filename.c_str(), &in_stats, program_mode, + eindex, one_to_one, recompress ); + if( infd < 0 ) { set_retval( retval, 1 ); continue; } + if( !check_tty_in( pp.name(), infd, program_mode, retval ) ) continue; + if( one_to_one ) // open outfd after checking infd + { + if( program_mode == m_compress ) + set_c_outname( input_filename, true, true, volume_size > 0 ); + else set_d_outname( input_filename, eindex ); + if( !open_outstream( force, true ) ) + { close( infd ); set_retval( retval, 1 ); continue; } + } + } + + if( one_to_one && !check_tty_out( program_mode ) ) + { set_retval( retval, 1 ); return retval; } // don't delete a tty + + if( to_file && outfd < 0 ) // open outfd after checking infd + { + if( program_mode == m_compress ) set_c_outname( default_output_filename, + filenames_given, false, volume_size > 0 ); + else output_filename = default_output_filename; + if( !open_outstream( force, false ) || !check_tty_out( program_mode ) ) + return 1; // check tty only once and don't try to delete a tty + } + + const struct stat * const in_statsp = + ( input_filename.size() && one_to_one ) ? &in_stats : 0; + const unsigned long long cfile_size = + ( input_filename.size() && S_ISREG( in_stats.st_mode ) ) ? + ( in_stats.st_size + 99 ) / 100 : 0; + int tmp; + try { + if( program_mode == m_compress ) + tmp = compress( cfile_size, member_size, volume_size, infd, + encoder_options, pp, in_statsp, zero ); + else + tmp = decompress( cfile_size, infd, cl_opts, pp, program_mode == m_test ); + } + catch( std::bad_alloc & ) + { pp( ( program_mode == m_compress ) ? + "Not enough memory. Try a smaller dictionary size." : + "Not enough memory." ); tmp = 1; } + catch( Error & e ) { pp(); show_error( e.msg, errno ); tmp = 1; } + if( close( infd ) != 0 ) + { show_file_error( pp.name(), "Error closing input file", errno ); + set_retval( tmp, 1 ); } + set_retval( retval, tmp ); + if( tmp ) + { if( program_mode != m_test ) cleanup_and_fail( retval ); + else ++failed_tests; } + + if( delete_output_on_interrupt && one_to_one ) + close_and_set_permissions( in_statsp ); + if( input_filename.size() && !keep_input_files && one_to_one && + ( program_mode != m_compress || volume_size == 0 ) ) + std::remove( input_filename.c_str() ); + } + if( delete_output_on_interrupt ) // -o + close_and_set_permissions( ( retval == 0 && !stdin_used && + filenames_given && filenames.size() == 1 ) ? &in_stats : 0 ); + else if( outfd >= 0 && close( outfd ) != 0 ) // -c + { + show_error( "Error closing stdout", errno ); + set_retval( retval, 1 ); + } + if( failed_tests > 0 && verbosity >= 1 && filenames.size() > 1 ) + std::fprintf( stderr, "%s: warning: %d %s failed the test.\n", + program_name, failed_tests, + ( failed_tests == 1 ) ? "file" : "files" ); + return retval; + } diff --git a/testsuite/check.sh b/testsuite/check.sh new file mode 100755 index 0000000..dd9a60a --- /dev/null +++ b/testsuite/check.sh @@ -0,0 +1,478 @@ +#! /bin/sh +# check script for Lzip - LZMA lossless data compressor +# Copyright (C) 2008-2024 Antonio Diaz Diaz. +# +# This script is free software: you have unlimited permission +# to copy, distribute, and modify it. + +LC_ALL=C +export LC_ALL +objdir=`pwd` +testdir=`cd "$1" ; pwd` +LZIP="${objdir}"/lzip +framework_failure() { echo "failure in testing framework" ; exit 1 ; } + +if [ ! -f "${LZIP}" ] || [ ! -x "${LZIP}" ] ; then + echo "${LZIP}: cannot execute" + exit 1 +fi + +[ -e "${LZIP}" ] 2> /dev/null || + { + echo "$0: a POSIX shell is required to run the tests" + echo "Try bash -c \"$0 $1 $2\"" + exit 1 + } + +if [ -d tmp ] ; then rm -rf tmp ; fi +mkdir tmp +cd "${objdir}"/tmp || framework_failure + +cat "${testdir}"/test.txt > in || framework_failure +in_lz="${testdir}"/test.txt.lz +in_em="${testdir}"/test_em.txt.lz +fox_lz="${testdir}"/fox.lz +fox6_lz="${testdir}"/fox6.lz +f6mk_lz="${testdir}"/fox6_mark.lz +fail=0 +test_failed() { fail=1 ; printf " $1" ; [ -z "$2" ] || printf "($2)" ; } + +printf "testing lzip-%s..." "$2" + +"${LZIP}" -fkqm4 in +[ $? = 1 ] || test_failed $LINENO +[ ! -e in.lz ] || test_failed $LINENO +"${LZIP}" -fkqm274 in +[ $? = 1 ] || test_failed $LINENO +[ ! -e in.lz ] || test_failed $LINENO +for i in bad_size -1 0 4095 513MiB 1G 1T 1P 1E 1Z 1Y 10KB ; do + "${LZIP}" -fkqs $i in + [ $? = 1 ] || test_failed $LINENO $i + [ ! -e in.lz ] || test_failed $LINENO $i +done +"${LZIP}" -lq in +[ $? = 2 ] || test_failed $LINENO +"${LZIP}" -tq in +[ $? = 2 ] || test_failed $LINENO +"${LZIP}" -tq < in +[ $? = 2 ] || test_failed $LINENO +"${LZIP}" -cdq in +[ $? = 2 ] || test_failed $LINENO +"${LZIP}" -cdq < in +[ $? = 2 ] || test_failed $LINENO +"${LZIP}" -dq -o in < "${in_lz}" +[ $? = 1 ] || test_failed $LINENO +"${LZIP}" -dq -o in "${in_lz}" +[ $? = 1 ] || test_failed $LINENO +"${LZIP}" -dq -o out nx_file.lz +[ $? = 1 ] || test_failed $LINENO +[ ! -e out ] || test_failed $LINENO +"${LZIP}" -q -o out.lz nx_file +[ $? = 1 ] || test_failed $LINENO +[ ! -e out.lz ] || test_failed $LINENO +"${LZIP}" -qf -S100k -o out in in +[ $? = 1 ] || test_failed $LINENO +{ [ ! -e out ] && [ ! -e out.lz ] ; } || test_failed $LINENO +# these are for code coverage +"${LZIP}" -lt "${in_lz}" 2> /dev/null +[ $? = 1 ] || test_failed $LINENO +"${LZIP}" -cdl "${in_lz}" 2> /dev/null +[ $? = 1 ] || test_failed $LINENO +"${LZIP}" -cdt "${in_lz}" 2> /dev/null +[ $? = 1 ] || test_failed $LINENO +"${LZIP}" -t -- nx_file.lz 2> /dev/null +[ $? = 1 ] || test_failed $LINENO +"${LZIP}" -t "" < /dev/null 2> /dev/null +[ $? = 1 ] || test_failed $LINENO +"${LZIP}" --help > /dev/null || test_failed $LINENO +"${LZIP}" -n1 -V > /dev/null || test_failed $LINENO +"${LZIP}" -m 2> /dev/null +[ $? = 1 ] || test_failed $LINENO +"${LZIP}" -z 2> /dev/null +[ $? = 1 ] || test_failed $LINENO +"${LZIP}" --bad_option 2> /dev/null +[ $? = 1 ] || test_failed $LINENO +"${LZIP}" --t 2> /dev/null +[ $? = 1 ] || test_failed $LINENO +"${LZIP}" --test=2 2> /dev/null +[ $? = 1 ] || test_failed $LINENO +"${LZIP}" --output= 2> /dev/null +[ $? = 1 ] || test_failed $LINENO +"${LZIP}" --output 2> /dev/null +[ $? = 1 ] || test_failed $LINENO +printf "LZIP\001-.............................." | "${LZIP}" -t 2> /dev/null +printf "LZIP\002-.............................." | "${LZIP}" -t 2> /dev/null +printf "LZIP\001+.............................." | "${LZIP}" -t 2> /dev/null + +printf "\ntesting decompression..." + +for i in "${in_lz}" "${in_em}" ; do + "${LZIP}" -lq "$i" || test_failed $LINENO "$i" + "${LZIP}" -t "$i" || test_failed $LINENO "$i" + "${LZIP}" -d "$i" -o out || test_failed $LINENO "$i" + cmp in out || test_failed $LINENO "$i" + "${LZIP}" -cd "$i" > out || test_failed $LINENO "$i" + cmp in out || test_failed $LINENO "$i" + "${LZIP}" -d "$i" -o - > out || test_failed $LINENO "$i" + cmp in out || test_failed $LINENO "$i" + "${LZIP}" -d < "$i" > out || test_failed $LINENO "$i" + cmp in out || test_failed $LINENO "$i" + rm -f out || framework_failure +done + +lines=`"${LZIP}" -tvv "${in_em}" 2>&1 | wc -l` || test_failed $LINENO +[ "${lines}" -eq 8 ] || test_failed $LINENO "${lines}" +"${LZIP}" -tq "${in_em}" --empty-error +[ $? = 2 ] || test_failed $LINENO + +lines=`"${LZIP}" -lvv "${in_em}" | wc -l` || test_failed $LINENO +[ "${lines}" -eq 11 ] || test_failed $LINENO "${lines}" +"${LZIP}" -lq "${in_em}" --empty-error +[ $? = 2 ] || test_failed $LINENO + +cat "${in_lz}" > out.lz || framework_failure +"${LZIP}" -dk out.lz || test_failed $LINENO +cmp in out || test_failed $LINENO +rm -f out || framework_failure +"${LZIP}" -cd "${fox_lz}" > fox || test_failed $LINENO +cat fox > copy || framework_failure +cat "${in_lz}" > copy.lz || framework_failure +"${LZIP}" -d copy.lz out.lz 2> /dev/null # skip copy, decompress out +[ $? = 1 ] || test_failed $LINENO +[ ! -e out.lz ] || test_failed $LINENO +cmp fox copy || test_failed $LINENO +cmp in out || test_failed $LINENO +"${LZIP}" -df copy.lz || test_failed $LINENO +[ ! -e copy.lz ] || test_failed $LINENO +cmp in copy || test_failed $LINENO +rm -f copy out || framework_failure + +cat "${in_lz}" > out.lz || framework_failure +"${LZIP}" -d -S100k out.lz || test_failed $LINENO # ignore -S +[ ! -e out.lz ] || test_failed $LINENO +cmp in out || test_failed $LINENO + +printf "to be overwritten" > out || framework_failure +"${LZIP}" -df -o out < "${in_lz}" || test_failed $LINENO +cmp in out || test_failed $LINENO +rm -f out || framework_failure +"${LZIP}" -d -o ./- "${in_lz}" || test_failed $LINENO +cmp in ./- || test_failed $LINENO +rm -f ./- || framework_failure +"${LZIP}" -d -o ./- < "${in_lz}" || test_failed $LINENO +cmp in ./- || test_failed $LINENO +rm -f ./- || framework_failure + +cat "${in_lz}" > anyothername || framework_failure +"${LZIP}" -dv - anyothername - < "${in_lz}" > out 2> /dev/null || + test_failed $LINENO +cmp in out || test_failed $LINENO +cmp in anyothername.out || test_failed $LINENO +rm -f out anyothername.out || framework_failure + +"${LZIP}" -lq in "${in_lz}" +[ $? = 2 ] || test_failed $LINENO +"${LZIP}" -lq nx_file.lz "${in_lz}" +[ $? = 1 ] || test_failed $LINENO +"${LZIP}" -tq in "${in_lz}" +[ $? = 2 ] || test_failed $LINENO +"${LZIP}" -tq nx_file.lz "${in_lz}" +[ $? = 1 ] || test_failed $LINENO +"${LZIP}" -cdq in "${in_lz}" > out +[ $? = 2 ] || test_failed $LINENO +cat out in | cmp in - || test_failed $LINENO # out must be empty +"${LZIP}" -cdq nx_file.lz "${in_lz}" > out # skip nx_file, decompress in +[ $? = 1 ] || test_failed $LINENO +cmp in out || test_failed $LINENO +rm -f out || framework_failure +cat "${in_lz}" > out.lz || framework_failure +for i in 1 2 3 4 5 6 7 ; do + printf "g" >> out.lz || framework_failure + "${LZIP}" -alvv out.lz "${in_lz}" > /dev/null 2>&1 + [ $? = 2 ] || test_failed $LINENO $i + "${LZIP}" -atvvvv out.lz "${in_lz}" 2> /dev/null + [ $? = 2 ] || test_failed $LINENO $i +done +"${LZIP}" -dq in out.lz +[ $? = 2 ] || test_failed $LINENO +[ -e out.lz ] || test_failed $LINENO +[ ! -e out ] || test_failed $LINENO +[ ! -e in.out ] || test_failed $LINENO +"${LZIP}" -dq nx_file.lz out.lz +[ $? = 1 ] || test_failed $LINENO +[ ! -e out.lz ] || test_failed $LINENO +[ ! -e nx_file ] || test_failed $LINENO +cmp in out || test_failed $LINENO +rm -f out || framework_failure + +cat in in > in2 || framework_failure +"${LZIP}" -lq "${in_lz}" "${in_lz}" || test_failed $LINENO +"${LZIP}" -t "${in_lz}" "${in_lz}" || test_failed $LINENO +"${LZIP}" -cd "${in_lz}" "${in_lz}" -o out > out2 || test_failed $LINENO +[ ! -e out ] || test_failed $LINENO # override -o +cmp in2 out2 || test_failed $LINENO +rm -f out2 || framework_failure +"${LZIP}" -d "${in_lz}" "${in_lz}" -o out2 || test_failed $LINENO +cmp in2 out2 || test_failed $LINENO +rm -f out2 || framework_failure + +cat "${in_lz}" "${in_lz}" > out2.lz || framework_failure +printf "\ngarbage" >> out2.lz || framework_failure +"${LZIP}" -tvvvv out2.lz 2> /dev/null || test_failed $LINENO +"${LZIP}" -alq out2.lz +[ $? = 2 ] || test_failed $LINENO +"${LZIP}" -atq out2.lz +[ $? = 2 ] || test_failed $LINENO +"${LZIP}" -atq < out2.lz +[ $? = 2 ] || test_failed $LINENO +"${LZIP}" -adkq out2.lz +[ $? = 2 ] || test_failed $LINENO +[ ! -e out2 ] || test_failed $LINENO +"${LZIP}" -adkq -o out2 < out2.lz +[ $? = 2 ] || test_failed $LINENO +[ ! -e out2 ] || test_failed $LINENO +printf "to be overwritten" > out2 || framework_failure +"${LZIP}" -df out2.lz || test_failed $LINENO +cmp in2 out2 || test_failed $LINENO +rm -f out2 || framework_failure + +"${LZIP}" -cd "${fox6_lz}" > out || test_failed $LINENO +"${LZIP}" -cd "${f6mk_lz}" > copy || test_failed $LINENO +cmp copy out || test_failed $LINENO +rm -f copy out || framework_failure +"${LZIP}" -lq "${f6mk_lz}" --marking-error +[ $? = 2 ] || test_failed $LINENO +"${LZIP}" -tq "${f6mk_lz}" --marking-error +[ $? = 2 ] || test_failed $LINENO + +"${LZIP}" -d "${fox_lz}" -o a/b/c/fox || test_failed $LINENO +cmp fox a/b/c/fox || test_failed $LINENO +rm -rf a || framework_failure +"${LZIP}" -d -o a/b/c/fox < "${fox_lz}" || test_failed $LINENO +cmp fox a/b/c/fox || test_failed $LINENO +rm -rf a || framework_failure +"${LZIP}" -dq "${fox_lz}" -o a/b/c/ +[ $? = 1 ] || test_failed $LINENO +[ ! -e a ] || test_failed $LINENO + +printf "\ntesting compression..." + +"${LZIP}" -c -0 in in in -S100k -o out3.lz > copy2.lz || test_failed $LINENO +[ ! -e out3.lz ] || test_failed $LINENO # override -o and -S +"${LZIP}" -0f in in --output=copy2.lz || test_failed $LINENO +"${LZIP}" -d copy2.lz -o out2 || test_failed $LINENO +[ -e copy2.lz ] || test_failed $LINENO +cmp in2 out2 || test_failed $LINENO +rm -f in2 out2 copy2.lz || framework_failure + +"${LZIP}" -cf "${in_lz}" > lzlz 2> /dev/null # /dev/null is a tty on OS/2 +[ $? = 1 ] || test_failed $LINENO +"${LZIP}" -Fvvm36 -o - "${in_lz}" > lzlz 2> /dev/null || test_failed $LINENO +"${LZIP}" -cd lzlz | "${LZIP}" -d > out || test_failed $LINENO +cmp in out || test_failed $LINENO +rm -f lzlz out || framework_failure + +"${LZIP}" -0 -o ./- in || test_failed $LINENO +"${LZIP}" -cd ./- | cmp in - || test_failed $LINENO +rm -f ./- || framework_failure +"${LZIP}" -0 -o ./- < in || test_failed $LINENO # add .lz +[ ! -e ./- ] || test_failed $LINENO +"${LZIP}" -cd -- -.lz | cmp in - || test_failed $LINENO +rm -f ./-.lz || framework_failure + +for i in s4Ki 0 1 2 3 4 5 6 7 8 9 ; do + "${LZIP}" -k -$i in || test_failed $LINENO $i + mv in.lz out.lz || test_failed $LINENO $i + printf "garbage" >> out.lz || framework_failure + "${LZIP}" -df out.lz || test_failed $LINENO $i + cmp in out || test_failed $LINENO $i + + "${LZIP}" -$i in -c > out || test_failed $LINENO $i + "${LZIP}" -$i in -o o_out || test_failed $LINENO $i # don't add .lz + [ ! -e o_out.lz ] || test_failed $LINENO + cmp out o_out || test_failed $LINENO $i + rm -f o_out || framework_failure + printf "g" >> out || framework_failure + "${LZIP}" -cd out > copy || test_failed $LINENO $i + cmp in copy || test_failed $LINENO $i + + "${LZIP}" -$i < in > out || test_failed $LINENO $i + "${LZIP}" -d < out > copy || test_failed $LINENO $i + cmp in copy || test_failed $LINENO $i + + rm -f out || framework_failure + printf "to be overwritten" > out.lz || framework_failure + "${LZIP}" -f -$i -o out < in || test_failed $LINENO $i # add .lz + [ ! -e out ] || test_failed $LINENO + "${LZIP}" -df -o copy < out.lz || test_failed $LINENO $i + cmp in copy || test_failed $LINENO $i +done +rm -f copy out.lz || framework_failure + +cat in in in in in in in in > in8 || framework_failure +"${LZIP}" -1s12 -S100k in8 || test_failed $LINENO +"${LZIP}" -t in800001.lz in800002.lz || test_failed $LINENO +"${LZIP}" -cd in800001.lz in800002.lz | cmp in8 - || test_failed $LINENO +[ ! -e in800003.lz ] || test_failed $LINENO +rm -f in800001.lz in800002.lz || framework_failure +"${LZIP}" -1s12 -S100k -o out.lz in8 || test_failed $LINENO +# ignore -S +"${LZIP}" -d out.lz00001.lz out.lz00002.lz -S100k -o out || test_failed $LINENO +cmp in8 out || test_failed $LINENO +"${LZIP}" -t out.lz00001.lz out.lz00002.lz || test_failed $LINENO +[ ! -e out.lz00003.lz ] || test_failed $LINENO +rm -f out out.lz00001.lz out.lz00002.lz || framework_failure +"${LZIP}" -1ks4Ki -b100000 in8 || test_failed $LINENO +"${LZIP}" -t in8.lz || test_failed $LINENO +"${LZIP}" -cd in8.lz -o out | cmp in8 - || test_failed $LINENO # override -o +[ ! -e out ] || test_failed $LINENO +rm -f in8 || framework_failure +"${LZIP}" -0 -S100k -o out < in8.lz || test_failed $LINENO +"${LZIP}" -t out00001.lz out00002.lz || test_failed $LINENO +"${LZIP}" -cd out00001.lz out00002.lz | cmp in8.lz - || test_failed $LINENO +[ ! -e out00003.lz ] || test_failed $LINENO +rm -f out00001.lz || framework_failure +"${LZIP}" -1 -S100k -o a/b/c/out < in8.lz || test_failed $LINENO +"${LZIP}" -t a/b/c/out00001.lz a/b/c/out00002.lz || test_failed $LINENO +"${LZIP}" -cd a/b/c/out00001.lz a/b/c/out00002.lz | cmp in8.lz - || + test_failed $LINENO +[ ! -e a/b/c/out00003.lz ] || test_failed $LINENO +rm -rf a || framework_failure +"${LZIP}" -0 -F -S100k in8.lz || test_failed $LINENO +"${LZIP}" -t in8.lz00001.lz in8.lz00002.lz || test_failed $LINENO +"${LZIP}" -cd in8.lz00001.lz in8.lz00002.lz | cmp in8.lz - || test_failed $LINENO +[ ! -e in8.lz00003.lz ] || test_failed $LINENO +rm -f in8.lz00001.lz in8.lz00002.lz || framework_failure +"${LZIP}" -0kF -b100k in8.lz || test_failed $LINENO +"${LZIP}" -t in8.lz.lz || test_failed $LINENO +"${LZIP}" -cd in8.lz.lz | cmp in8.lz - || test_failed $LINENO +rm -f in8.lz in8.lz.lz || framework_failure + +"${LZIP}" fox -o a/b/c/fox.lz || test_failed $LINENO +cmp "${fox_lz}" a/b/c/fox.lz || test_failed $LINENO +rm -rf a || framework_failure +"${LZIP}" -o a/b/c/fox.lz < fox || test_failed $LINENO +cmp "${fox_lz}" a/b/c/fox.lz || test_failed $LINENO +rm -rf a || framework_failure + +printf "\ntesting bad input..." + +headers='LZIp LZiP LZip LzIP LzIp LziP lZIP lZIp lZiP lzIP' +body='\001\014\000\203\377\373\377\377\300\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000$\000\000\000\000\000\000\000' +cat "${in_lz}" > int.lz || framework_failure +printf "LZIP${body}" >> int.lz || framework_failure +if "${LZIP}" -tq int.lz ; then + for header in ${headers} ; do + printf "${header}${body}" > int.lz || framework_failure + "${LZIP}" -lq int.lz # first member + [ $? = 2 ] || test_failed $LINENO ${header} + "${LZIP}" -tq int.lz + [ $? = 2 ] || test_failed $LINENO ${header} + "${LZIP}" -tq < int.lz + [ $? = 2 ] || test_failed $LINENO ${header} + "${LZIP}" -cdq int.lz > /dev/null + [ $? = 2 ] || test_failed $LINENO ${header} + "${LZIP}" -lq --loose-trailing int.lz + [ $? = 2 ] || test_failed $LINENO ${header} + "${LZIP}" -tq --loose-trailing int.lz + [ $? = 2 ] || test_failed $LINENO ${header} + "${LZIP}" -tq --loose-trailing < int.lz + [ $? = 2 ] || test_failed $LINENO ${header} + "${LZIP}" -cdq --loose-trailing int.lz > /dev/null + [ $? = 2 ] || test_failed $LINENO ${header} + cat "${in_lz}" > int.lz || framework_failure + printf "${header}${body}" >> int.lz || framework_failure + "${LZIP}" -lq int.lz # trailing data + [ $? = 2 ] || test_failed $LINENO ${header} + "${LZIP}" -tq int.lz + [ $? = 2 ] || test_failed $LINENO ${header} + "${LZIP}" -tq < int.lz + [ $? = 2 ] || test_failed $LINENO ${header} + "${LZIP}" -cdq int.lz > /dev/null + [ $? = 2 ] || test_failed $LINENO ${header} + "${LZIP}" -lq --loose-trailing int.lz || + test_failed $LINENO ${header} + "${LZIP}" -t --loose-trailing int.lz || + test_failed $LINENO ${header} + "${LZIP}" -t --loose-trailing < int.lz || + test_failed $LINENO ${header} + "${LZIP}" -cd --loose-trailing int.lz > /dev/null || + test_failed $LINENO ${header} + "${LZIP}" -lq --loose-trailing --trailing-error int.lz + [ $? = 2 ] || test_failed $LINENO ${header} + "${LZIP}" -tq --loose-trailing --trailing-error int.lz + [ $? = 2 ] || test_failed $LINENO ${header} + "${LZIP}" -tq --loose-trailing --trailing-error < int.lz + [ $? = 2 ] || test_failed $LINENO ${header} + "${LZIP}" -cdq --loose-trailing --trailing-error int.lz > /dev/null + [ $? = 2 ] || test_failed $LINENO ${header} + done +else + printf "\nwarning: skipping header test: 'printf' does not work on your system." +fi +rm -f int.lz || framework_failure + +for i in fox_v2.lz fox_s11.lz fox_de20.lz \ + fox_bcrc.lz fox_crc0.lz fox_das46.lz fox_mes81.lz ; do + "${LZIP}" -tq "${testdir}"/$i + [ $? = 2 ] || test_failed $LINENO $i +done + +for i in fox_bcrc.lz fox_crc0.lz fox_das46.lz fox_mes81.lz ; do + "${LZIP}" -cdq "${testdir}"/$i > out + [ $? = 2 ] || test_failed $LINENO $i + cmp fox out || test_failed $LINENO $i +done +rm -f fox out || framework_failure + +cat "${in_lz}" "${in_lz}" > in2.lz || framework_failure +cat "${in_lz}" "${in_lz}" "${in_lz}" > in3.lz || framework_failure +if dd if=in3.lz of=trunc.lz bs=14752 count=1 2> /dev/null && + [ -e trunc.lz ] && cmp in2.lz trunc.lz > /dev/null 2>&1 ; then + for i in 6 20 14734 14753 14754 14755 14756 14757 14758 ; do + dd if=in3.lz of=trunc.lz bs=$i count=1 2> /dev/null + "${LZIP}" -lq trunc.lz + [ $? = 2 ] || test_failed $LINENO $i + "${LZIP}" -tq trunc.lz + [ $? = 2 ] || test_failed $LINENO $i + "${LZIP}" -tq < trunc.lz + [ $? = 2 ] || test_failed $LINENO $i + "${LZIP}" -cdq trunc.lz > /dev/null + [ $? = 2 ] || test_failed $LINENO $i + "${LZIP}" -dq < trunc.lz > /dev/null + [ $? = 2 ] || test_failed $LINENO $i + done +else + printf "\nwarning: skipping truncation test: 'dd' does not work on your system." +fi +rm -f in2.lz in3.lz trunc.lz || framework_failure + +cat "${in_lz}" > ingin.lz || framework_failure +printf "g" >> ingin.lz || framework_failure +cat "${in_lz}" >> ingin.lz || framework_failure +"${LZIP}" -lq ingin.lz +[ $? = 2 ] || test_failed $LINENO +"${LZIP}" -atq ingin.lz +[ $? = 2 ] || test_failed $LINENO +"${LZIP}" -atq < ingin.lz +[ $? = 2 ] || test_failed $LINENO +"${LZIP}" -acdq ingin.lz > /dev/null +[ $? = 2 ] || test_failed $LINENO +"${LZIP}" -adq < ingin.lz > /dev/null +[ $? = 2 ] || test_failed $LINENO +"${LZIP}" -t ingin.lz || test_failed $LINENO +"${LZIP}" -t < ingin.lz || test_failed $LINENO +"${LZIP}" -cd ingin.lz > out || test_failed $LINENO +cmp in out || test_failed $LINENO +"${LZIP}" -d < ingin.lz > out || test_failed $LINENO +cmp in out || test_failed $LINENO +rm -f out ingin.lz || framework_failure + +echo +if [ ${fail} = 0 ] ; then + echo "tests completed successfully." + cd "${objdir}" && rm -r tmp +else + echo "tests failed." +fi +exit ${fail} diff --git a/testsuite/fox.lz b/testsuite/fox.lz new file mode 100644 index 0000000..509da82 Binary files /dev/null and b/testsuite/fox.lz differ diff --git a/testsuite/fox6.lz b/testsuite/fox6.lz new file mode 100644 index 0000000..8401b99 Binary files /dev/null and b/testsuite/fox6.lz differ diff --git a/testsuite/fox6_mark.lz b/testsuite/fox6_mark.lz new file mode 100644 index 0000000..32b2ac0 Binary files /dev/null and b/testsuite/fox6_mark.lz differ diff --git a/testsuite/fox_bcrc.lz b/testsuite/fox_bcrc.lz new file mode 100644 index 0000000..8f6a7c4 Binary files /dev/null and b/testsuite/fox_bcrc.lz differ diff --git a/testsuite/fox_crc0.lz b/testsuite/fox_crc0.lz new file mode 100644 index 0000000..1abe926 Binary files /dev/null and b/testsuite/fox_crc0.lz differ diff --git a/testsuite/fox_das46.lz b/testsuite/fox_das46.lz new file mode 100644 index 0000000..43ed9f9 Binary files /dev/null and b/testsuite/fox_das46.lz differ diff --git a/testsuite/fox_de20.lz b/testsuite/fox_de20.lz new file mode 100644 index 0000000..10949d8 Binary files /dev/null and b/testsuite/fox_de20.lz differ diff --git a/testsuite/fox_mes81.lz b/testsuite/fox_mes81.lz new file mode 100644 index 0000000..d50ef2e Binary files /dev/null and b/testsuite/fox_mes81.lz differ diff --git a/testsuite/fox_s11.lz b/testsuite/fox_s11.lz new file mode 100644 index 0000000..dca909c Binary files /dev/null and b/testsuite/fox_s11.lz differ diff --git a/testsuite/fox_v2.lz b/testsuite/fox_v2.lz new file mode 100644 index 0000000..8620981 Binary files /dev/null and b/testsuite/fox_v2.lz differ diff --git a/testsuite/test.txt b/testsuite/test.txt new file mode 100644 index 0000000..9196a3a --- /dev/null +++ b/testsuite/test.txt @@ -0,0 +1,676 @@ + GNU GENERAL PUBLIC LICENSE + Version 2, June 1991 + + Copyright (C) 1989, 1991 Free Software Foundation, Inc., + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The licenses for most software are designed to take away your +freedom to share and change it. By contrast, the GNU General Public +License is intended to guarantee your freedom to share and change free +software--to make sure the software is free for all its users. This +General Public License applies to most of the Free Software +Foundation's software and to any other program whose authors commit to +using it. (Some other Free Software Foundation software is covered by +the GNU Lesser General Public License instead.) You can apply it to +your programs, too. + + When we speak of free software, we are referring to freedom, not +price. Our General Public Licenses are designed to make sure that you +have the freedom to distribute copies of free software (and charge for +this service if you wish), that you receive source code or can get it +if you want it, that you can change the software or use pieces of it +in new free programs; and that you know you can do these things. + + To protect your rights, we need to make restrictions that forbid +anyone to deny you these rights or to ask you to surrender the rights. +These restrictions translate to certain responsibilities for you if you +distribute copies of the software, or if you modify it. + + For example, if you distribute copies of such a program, whether +gratis or for a fee, you must give the recipients all the rights that +you have. You must make sure that they, too, receive or can get the +source code. And you must show them these terms so they know their +rights. + + We protect your rights with two steps: (1) copyright the software, and +(2) offer you this license which gives you legal permission to copy, +distribute and/or modify the software. + + Also, for each author's protection and ours, we want to make certain +that everyone understands that there is no warranty for this free +software. If the software is modified by someone else and passed on, we +want its recipients to know that what they have is not the original, so +that any problems introduced by others will not reflect on the original +authors' reputations. + + Finally, any free program is threatened constantly by software +patents. We wish to avoid the danger that redistributors of a free +program will individually obtain patent licenses, in effect making the +program proprietary. To prevent this, we have made it clear that any +patent must be licensed for everyone's free use or not licensed at all. + + The precise terms and conditions for copying, distribution and +modification follow. + + GNU GENERAL PUBLIC LICENSE + TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION + + 0. This License applies to any program or other work which contains +a notice placed by the copyright holder saying it may be distributed +under the terms of this General Public License. The "Program", below, +refers to any such program or work, and a "work based on the Program" +means either the Program or any derivative work under copyright law: +that is to say, a work containing the Program or a portion of it, +either verbatim or with modifications and/or translated into another +language. (Hereinafter, translation is included without limitation in +the term "modification".) Each licensee is addressed as "you". + +Activities other than copying, distribution and modification are not +covered by this License; they are outside its scope. The act of +running the Program is not restricted, and the output from the Program +is covered only if its contents constitute a work based on the +Program (independent of having been made by running the Program). +Whether that is true depends on what the Program does. + + 1. You may copy and distribute verbatim copies of the Program's +source code as you receive it, in any medium, provided that you +conspicuously and appropriately publish on each copy an appropriate +copyright notice and disclaimer of warranty; keep intact all the +notices that refer to this License and to the absence of any warranty; +and give any other recipients of the Program a copy of this License +along with the Program. + +You may charge a fee for the physical act of transferring a copy, and +you may at your option offer warranty protection in exchange for a fee. + + 2. You may modify your copy or copies of the Program or any portion +of it, thus forming a work based on the Program, and copy and +distribute such modifications or work under the terms of Section 1 +above, provided that you also meet all of these conditions: + + a) You must cause the modified files to carry prominent notices + stating that you changed the files and the date of any change. + + b) You must cause any work that you distribute or publish, that in + whole or in part contains or is derived from the Program or any + part thereof, to be licensed as a whole at no charge to all third + parties under the terms of this License. + + c) If the modified program normally reads commands interactively + when run, you must cause it, when started running for such + interactive use in the most ordinary way, to print or display an + announcement including an appropriate copyright notice and a + notice that there is no warranty (or else, saying that you provide + a warranty) and that users may redistribute the program under + these conditions, and telling the user how to view a copy of this + License. (Exception: if the Program itself is interactive but + does not normally print such an announcement, your work based on + the Program is not required to print an announcement.) + +These requirements apply to the modified work as a whole. If +identifiable sections of that work are not derived from the Program, +and can be reasonably considered independent and separate works in +themselves, then this License, and its terms, do not apply to those +sections when you distribute them as separate works. But when you +distribute the same sections as part of a whole which is a work based +on the Program, the distribution of the whole must be on the terms of +this License, whose permissions for other licensees extend to the +entire whole, and thus to each and every part regardless of who wrote it. + +Thus, it is not the intent of this section to claim rights or contest +your rights to work written entirely by you; rather, the intent is to +exercise the right to control the distribution of derivative or +collective works based on the Program. + +In addition, mere aggregation of another work not based on the Program +with the Program (or with a work based on the Program) on a volume of +a storage or distribution medium does not bring the other work under +the scope of this License. + + 3. You may copy and distribute the Program (or a work based on it, +under Section 2) in object code or executable form under the terms of +Sections 1 and 2 above provided that you also do one of the following: + + a) Accompany it with the complete corresponding machine-readable + source code, which must be distributed under the terms of Sections + 1 and 2 above on a medium customarily used for software interchange; or, + + b) Accompany it with a written offer, valid for at least three + years, to give any third party, for a charge no more than your + cost of physically performing source distribution, a complete + machine-readable copy of the corresponding source code, to be + distributed under the terms of Sections 1 and 2 above on a medium + customarily used for software interchange; or, + + c) Accompany it with the information you received as to the offer + to distribute corresponding source code. (This alternative is + allowed only for noncommercial distribution and only if you + received the program in object code or executable form with such + an offer, in accord with Subsection b above.) + +The source code for a work means the preferred form of the work for +making modifications to it. For an executable work, complete source +code means all the source code for all modules it contains, plus any +associated interface definition files, plus the scripts used to +control compilation and installation of the executable. However, as a +special exception, the source code distributed need not include +anything that is normally distributed (in either source or binary +form) with the major components (compiler, kernel, and so on) of the +operating system on which the executable runs, unless that component +itself accompanies the executable. + +If distribution of executable or object code is made by offering +access to copy from a designated place, then offering equivalent +access to copy the source code from the same place counts as +distribution of the source code, even though third parties are not +compelled to copy the source along with the object code. + + 4. You may not copy, modify, sublicense, or distribute the Program +except as expressly provided under this License. Any attempt +otherwise to copy, modify, sublicense or distribute the Program is +void, and will automatically terminate your rights under this License. +However, parties who have received copies, or rights, from you under +this License will not have their licenses terminated so long as such +parties remain in full compliance. + + 5. You are not required to accept this License, since you have not +signed it. However, nothing else grants you permission to modify or +distribute the Program or its derivative works. These actions are +prohibited by law if you do not accept this License. Therefore, by +modifying or distributing the Program (or any work based on the +Program), you indicate your acceptance of this License to do so, and +all its terms and conditions for copying, distributing or modifying +the Program or works based on it. + + 6. Each time you redistribute the Program (or any work based on the +Program), the recipient automatically receives a license from the +original licensor to copy, distribute or modify the Program subject to +these terms and conditions. You may not impose any further +restrictions on the recipients' exercise of the rights granted herein. +You are not responsible for enforcing compliance by third parties to +this License. + + 7. If, as a consequence of a court judgment or allegation of patent +infringement or for any other reason (not limited to patent issues), +conditions are imposed on you (whether by court order, agreement or +otherwise) that contradict the conditions of this License, they do not +excuse you from the conditions of this License. If you cannot +distribute so as to satisfy simultaneously your obligations under this +License and any other pertinent obligations, then as a consequence you +may not distribute the Program at all. For example, if a patent +license would not permit royalty-free redistribution of the Program by +all those who receive copies directly or indirectly through you, then +the only way you could satisfy both it and this License would be to +refrain entirely from distribution of the Program. + +If any portion of this section is held invalid or unenforceable under +any particular circumstance, the balance of the section is intended to +apply and the section as a whole is intended to apply in other +circumstances. + +It is not the purpose of this section to induce you to infringe any +patents or other property right claims or to contest validity of any +such claims; this section has the sole purpose of protecting the +integrity of the free software distribution system, which is +implemented by public license practices. Many people have made +generous contributions to the wide range of software distributed +through that system in reliance on consistent application of that +system; it is up to the author/donor to decide if he or she is willing +to distribute software through any other system and a licensee cannot +impose that choice. + +This section is intended to make thoroughly clear what is believed to +be a consequence of the rest of this License. + + 8. If the distribution and/or use of the Program is restricted in +certain countries either by patents or by copyrighted interfaces, the +original copyright holder who places the Program under this License +may add an explicit geographical distribution limitation excluding +those countries, so that distribution is permitted only in or among +countries not thus excluded. In such case, this License incorporates +the limitation as if written in the body of this License. + + 9. The Free Software Foundation may publish revised and/or new versions +of the General Public License from time to time. Such new versions will +be similar in spirit to the present version, but may differ in detail to +address new problems or concerns. + +Each version is given a distinguishing version number. If the Program +specifies a version number of this License which applies to it and "any +later version", you have the option of following the terms and conditions +either of that version or of any later version published by the Free +Software Foundation. If the Program does not specify a version number of +this License, you may choose any version ever published by the Free Software +Foundation. + + 10. If you wish to incorporate parts of the Program into other free +programs whose distribution conditions are different, write to the author +to ask for permission. For software which is copyrighted by the Free +Software Foundation, write to the Free Software Foundation; we sometimes +make exceptions for this. Our decision will be guided by the two goals +of preserving the free status of all derivatives of our free software and +of promoting the sharing and reuse of software generally. + + NO WARRANTY + + 11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY +FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN +OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES +PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED +OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF +MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS +TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE +PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, +REPAIR OR CORRECTION. + + 12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING +WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR +REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, +INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING +OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED +TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY +YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER +PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE +POSSIBILITY OF SUCH DAMAGES. + + END OF TERMS AND CONDITIONS + + How to Apply These Terms to Your New Programs + + If you develop a new program, and you want it to be of the greatest +possible use to the public, the best way to achieve this is to make it +free software which everyone can redistribute and change under these terms. + + To do so, attach the following notices to the program. It is safest +to attach them to the start of each source file to most effectively +convey the exclusion of warranty; and each file should have at least +the "copyright" line and a pointer to where the full notice is found. + + + Copyright (C) + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . + +Also add information on how to contact you by electronic and paper mail. + +If the program is interactive, make it output a short notice like this +when it starts in an interactive mode: + + Gnomovision version 69, Copyright (C) + Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + +The hypothetical commands `show w' and `show c' should show the appropriate +parts of the General Public License. Of course, the commands you use may +be called something other than `show w' and `show c'; they could even be +mouse-clicks or menu items--whatever suits your program. + +You should also get your employer (if you work as a programmer) or your +school, if any, to sign a "copyright disclaimer" for the program, if +necessary. Here is a sample; alter the names: + + Yoyodyne, Inc., hereby disclaims all copyright interest in the program + `Gnomovision' (which makes passes at compilers) written by James Hacker. + + , 1 April 1989 + Ty Coon, President of Vice + +This General Public License does not permit incorporating your program into +proprietary programs. If your program is a subroutine library, you may +consider it more useful to permit linking proprietary applications with the +library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. + GNU GENERAL PUBLIC LICENSE + Version 2, June 1991 + + Copyright (C) 1989, 1991 Free Software Foundation, Inc., + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The licenses for most software are designed to take away your +freedom to share and change it. By contrast, the GNU General Public +License is intended to guarantee your freedom to share and change free +software--to make sure the software is free for all its users. This +General Public License applies to most of the Free Software +Foundation's software and to any other program whose authors commit to +using it. (Some other Free Software Foundation software is covered by +the GNU Lesser General Public License instead.) You can apply it to +your programs, too. + + When we speak of free software, we are referring to freedom, not +price. Our General Public Licenses are designed to make sure that you +have the freedom to distribute copies of free software (and charge for +this service if you wish), that you receive source code or can get it +if you want it, that you can change the software or use pieces of it +in new free programs; and that you know you can do these things. + + To protect your rights, we need to make restrictions that forbid +anyone to deny you these rights or to ask you to surrender the rights. +These restrictions translate to certain responsibilities for you if you +distribute copies of the software, or if you modify it. + + For example, if you distribute copies of such a program, whether +gratis or for a fee, you must give the recipients all the rights that +you have. You must make sure that they, too, receive or can get the +source code. And you must show them these terms so they know their +rights. + + We protect your rights with two steps: (1) copyright the software, and +(2) offer you this license which gives you legal permission to copy, +distribute and/or modify the software. + + Also, for each author's protection and ours, we want to make certain +that everyone understands that there is no warranty for this free +software. If the software is modified by someone else and passed on, we +want its recipients to know that what they have is not the original, so +that any problems introduced by others will not reflect on the original +authors' reputations. + + Finally, any free program is threatened constantly by software +patents. We wish to avoid the danger that redistributors of a free +program will individually obtain patent licenses, in effect making the +program proprietary. To prevent this, we have made it clear that any +patent must be licensed for everyone's free use or not licensed at all. + + The precise terms and conditions for copying, distribution and +modification follow. + + GNU GENERAL PUBLIC LICENSE + TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION + + 0. This License applies to any program or other work which contains +a notice placed by the copyright holder saying it may be distributed +under the terms of this General Public License. The "Program", below, +refers to any such program or work, and a "work based on the Program" +means either the Program or any derivative work under copyright law: +that is to say, a work containing the Program or a portion of it, +either verbatim or with modifications and/or translated into another +language. (Hereinafter, translation is included without limitation in +the term "modification".) Each licensee is addressed as "you". + +Activities other than copying, distribution and modification are not +covered by this License; they are outside its scope. The act of +running the Program is not restricted, and the output from the Program +is covered only if its contents constitute a work based on the +Program (independent of having been made by running the Program). +Whether that is true depends on what the Program does. + + 1. You may copy and distribute verbatim copies of the Program's +source code as you receive it, in any medium, provided that you +conspicuously and appropriately publish on each copy an appropriate +copyright notice and disclaimer of warranty; keep intact all the +notices that refer to this License and to the absence of any warranty; +and give any other recipients of the Program a copy of this License +along with the Program. + +You may charge a fee for the physical act of transferring a copy, and +you may at your option offer warranty protection in exchange for a fee. + + 2. You may modify your copy or copies of the Program or any portion +of it, thus forming a work based on the Program, and copy and +distribute such modifications or work under the terms of Section 1 +above, provided that you also meet all of these conditions: + + a) You must cause the modified files to carry prominent notices + stating that you changed the files and the date of any change. + + b) You must cause any work that you distribute or publish, that in + whole or in part contains or is derived from the Program or any + part thereof, to be licensed as a whole at no charge to all third + parties under the terms of this License. + + c) If the modified program normally reads commands interactively + when run, you must cause it, when started running for such + interactive use in the most ordinary way, to print or display an + announcement including an appropriate copyright notice and a + notice that there is no warranty (or else, saying that you provide + a warranty) and that users may redistribute the program under + these conditions, and telling the user how to view a copy of this + License. (Exception: if the Program itself is interactive but + does not normally print such an announcement, your work based on + the Program is not required to print an announcement.) + +These requirements apply to the modified work as a whole. If +identifiable sections of that work are not derived from the Program, +and can be reasonably considered independent and separate works in +themselves, then this License, and its terms, do not apply to those +sections when you distribute them as separate works. But when you +distribute the same sections as part of a whole which is a work based +on the Program, the distribution of the whole must be on the terms of +this License, whose permissions for other licensees extend to the +entire whole, and thus to each and every part regardless of who wrote it. + +Thus, it is not the intent of this section to claim rights or contest +your rights to work written entirely by you; rather, the intent is to +exercise the right to control the distribution of derivative or +collective works based on the Program. + +In addition, mere aggregation of another work not based on the Program +with the Program (or with a work based on the Program) on a volume of +a storage or distribution medium does not bring the other work under +the scope of this License. + + 3. You may copy and distribute the Program (or a work based on it, +under Section 2) in object code or executable form under the terms of +Sections 1 and 2 above provided that you also do one of the following: + + a) Accompany it with the complete corresponding machine-readable + source code, which must be distributed under the terms of Sections + 1 and 2 above on a medium customarily used for software interchange; or, + + b) Accompany it with a written offer, valid for at least three + years, to give any third party, for a charge no more than your + cost of physically performing source distribution, a complete + machine-readable copy of the corresponding source code, to be + distributed under the terms of Sections 1 and 2 above on a medium + customarily used for software interchange; or, + + c) Accompany it with the information you received as to the offer + to distribute corresponding source code. (This alternative is + allowed only for noncommercial distribution and only if you + received the program in object code or executable form with such + an offer, in accord with Subsection b above.) + +The source code for a work means the preferred form of the work for +making modifications to it. For an executable work, complete source +code means all the source code for all modules it contains, plus any +associated interface definition files, plus the scripts used to +control compilation and installation of the executable. However, as a +special exception, the source code distributed need not include +anything that is normally distributed (in either source or binary +form) with the major components (compiler, kernel, and so on) of the +operating system on which the executable runs, unless that component +itself accompanies the executable. + +If distribution of executable or object code is made by offering +access to copy from a designated place, then offering equivalent +access to copy the source code from the same place counts as +distribution of the source code, even though third parties are not +compelled to copy the source along with the object code. + + 4. You may not copy, modify, sublicense, or distribute the Program +except as expressly provided under this License. Any attempt +otherwise to copy, modify, sublicense or distribute the Program is +void, and will automatically terminate your rights under this License. +However, parties who have received copies, or rights, from you under +this License will not have their licenses terminated so long as such +parties remain in full compliance. + + 5. You are not required to accept this License, since you have not +signed it. However, nothing else grants you permission to modify or +distribute the Program or its derivative works. These actions are +prohibited by law if you do not accept this License. Therefore, by +modifying or distributing the Program (or any work based on the +Program), you indicate your acceptance of this License to do so, and +all its terms and conditions for copying, distributing or modifying +the Program or works based on it. + + 6. Each time you redistribute the Program (or any work based on the +Program), the recipient automatically receives a license from the +original licensor to copy, distribute or modify the Program subject to +these terms and conditions. You may not impose any further +restrictions on the recipients' exercise of the rights granted herein. +You are not responsible for enforcing compliance by third parties to +this License. + + 7. If, as a consequence of a court judgment or allegation of patent +infringement or for any other reason (not limited to patent issues), +conditions are imposed on you (whether by court order, agreement or +otherwise) that contradict the conditions of this License, they do not +excuse you from the conditions of this License. If you cannot +distribute so as to satisfy simultaneously your obligations under this +License and any other pertinent obligations, then as a consequence you +may not distribute the Program at all. For example, if a patent +license would not permit royalty-free redistribution of the Program by +all those who receive copies directly or indirectly through you, then +the only way you could satisfy both it and this License would be to +refrain entirely from distribution of the Program. + +If any portion of this section is held invalid or unenforceable under +any particular circumstance, the balance of the section is intended to +apply and the section as a whole is intended to apply in other +circumstances. + +It is not the purpose of this section to induce you to infringe any +patents or other property right claims or to contest validity of any +such claims; this section has the sole purpose of protecting the +integrity of the free software distribution system, which is +implemented by public license practices. Many people have made +generous contributions to the wide range of software distributed +through that system in reliance on consistent application of that +system; it is up to the author/donor to decide if he or she is willing +to distribute software through any other system and a licensee cannot +impose that choice. + +This section is intended to make thoroughly clear what is believed to +be a consequence of the rest of this License. + + 8. If the distribution and/or use of the Program is restricted in +certain countries either by patents or by copyrighted interfaces, the +original copyright holder who places the Program under this License +may add an explicit geographical distribution limitation excluding +those countries, so that distribution is permitted only in or among +countries not thus excluded. In such case, this License incorporates +the limitation as if written in the body of this License. + + 9. The Free Software Foundation may publish revised and/or new versions +of the General Public License from time to time. Such new versions will +be similar in spirit to the present version, but may differ in detail to +address new problems or concerns. + +Each version is given a distinguishing version number. If the Program +specifies a version number of this License which applies to it and "any +later version", you have the option of following the terms and conditions +either of that version or of any later version published by the Free +Software Foundation. If the Program does not specify a version number of +this License, you may choose any version ever published by the Free Software +Foundation. + + 10. If you wish to incorporate parts of the Program into other free +programs whose distribution conditions are different, write to the author +to ask for permission. For software which is copyrighted by the Free +Software Foundation, write to the Free Software Foundation; we sometimes +make exceptions for this. Our decision will be guided by the two goals +of preserving the free status of all derivatives of our free software and +of promoting the sharing and reuse of software generally. + + NO WARRANTY + + 11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY +FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN +OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES +PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED +OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF +MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS +TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE +PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, +REPAIR OR CORRECTION. + + 12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING +WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR +REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, +INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING +OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED +TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY +YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER +PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE +POSSIBILITY OF SUCH DAMAGES. + + END OF TERMS AND CONDITIONS + + How to Apply These Terms to Your New Programs + + If you develop a new program, and you want it to be of the greatest +possible use to the public, the best way to achieve this is to make it +free software which everyone can redistribute and change under these terms. + + To do so, attach the following notices to the program. It is safest +to attach them to the start of each source file to most effectively +convey the exclusion of warranty; and each file should have at least +the "copyright" line and a pointer to where the full notice is found. + + + Copyright (C) + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . + +Also add information on how to contact you by electronic and paper mail. + +If the program is interactive, make it output a short notice like this +when it starts in an interactive mode: + + Gnomovision version 69, Copyright (C) + Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + +The hypothetical commands `show w' and `show c' should show the appropriate +parts of the General Public License. Of course, the commands you use may +be called something other than `show w' and `show c'; they could even be +mouse-clicks or menu items--whatever suits your program. + +You should also get your employer (if you work as a programmer) or your +school, if any, to sign a "copyright disclaimer" for the program, if +necessary. Here is a sample; alter the names: + + Yoyodyne, Inc., hereby disclaims all copyright interest in the program + `Gnomovision' (which makes passes at compilers) written by James Hacker. + + , 1 April 1989 + Ty Coon, President of Vice + +This General Public License does not permit incorporating your program into +proprietary programs. If your program is a subroutine library, you may +consider it more useful to permit linking proprietary applications with the +library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. diff --git a/testsuite/test.txt.lz b/testsuite/test.txt.lz new file mode 100644 index 0000000..22cea6e Binary files /dev/null and b/testsuite/test.txt.lz differ diff --git a/testsuite/test_em.txt.lz b/testsuite/test_em.txt.lz new file mode 100644 index 0000000..7e96250 Binary files /dev/null and b/testsuite/test_em.txt.lz differ -- cgit v1.2.3