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diff --git a/comm/third_party/bzip2/README b/comm/third_party/bzip2/README new file mode 100644 index 0000000000..b9c6099fd1 --- /dev/null +++ b/comm/third_party/bzip2/README @@ -0,0 +1,196 @@ + +This is the README for bzip2/libzip2. +This version is fully compatible with the previous public releases. + +------------------------------------------------------------------ +This file is part of bzip2/libbzip2, a program and library for +lossless, block-sorting data compression. + +bzip2/libbzip2 version 1.0.8 of 13 July 2019 +Copyright (C) 1996-2019 Julian Seward <jseward@acm.org> + +Please read the WARNING, DISCLAIMER and PATENTS sections in this file. + +This program is released under the terms of the license contained +in the file LICENSE. +------------------------------------------------------------------ + +Complete documentation is available in Postscript form (manual.ps), +PDF (manual.pdf) or html (manual.html). A plain-text version of the +manual page is available as bzip2.txt. + + +HOW TO BUILD -- UNIX + +Type 'make'. This builds the library libbz2.a and then the programs +bzip2 and bzip2recover. Six self-tests are run. If the self-tests +complete ok, carry on to installation: + +To install in /usr/local/bin, /usr/local/lib, /usr/local/man and +/usr/local/include, type + + make install + +To install somewhere else, eg, /xxx/yyy/{bin,lib,man,include}, type + + make install PREFIX=/xxx/yyy + +If you are (justifiably) paranoid and want to see what 'make install' +is going to do, you can first do + + make -n install or + make -n install PREFIX=/xxx/yyy respectively. + +The -n instructs make to show the commands it would execute, but not +actually execute them. + + +HOW TO BUILD -- UNIX, shared library libbz2.so. + +Do 'make -f Makefile-libbz2_so'. This Makefile seems to work for +Linux-ELF (RedHat 7.2 on an x86 box), with gcc. I make no claims +that it works for any other platform, though I suspect it probably +will work for most platforms employing both ELF and gcc. + +bzip2-shared, a client of the shared library, is also built, but not +self-tested. So I suggest you also build using the normal Makefile, +since that conducts a self-test. A second reason to prefer the +version statically linked to the library is that, on x86 platforms, +building shared objects makes a valuable register (%ebx) unavailable +to gcc, resulting in a slowdown of 10%-20%, at least for bzip2. + +Important note for people upgrading .so's from 0.9.0/0.9.5 to version +1.0.X. All the functions in the library have been renamed, from (eg) +bzCompress to BZ2_bzCompress, to avoid namespace pollution. +Unfortunately this means that the libbz2.so created by +Makefile-libbz2_so will not work with any program which used an older +version of the library. I do encourage library clients to make the +effort to upgrade to use version 1.0, since it is both faster and more +robust than previous versions. + + +HOW TO BUILD -- Windows 95, NT, DOS, Mac, etc. + +It's difficult for me to support compilation on all these platforms. +My approach is to collect binaries for these platforms, and put them +on the master web site (https://sourceware.org/bzip2/). Look there. However +(FWIW), bzip2-1.0.X is very standard ANSI C and should compile +unmodified with MS Visual C. If you have difficulties building, you +might want to read README.COMPILATION.PROBLEMS. + +At least using MS Visual C++ 6, you can build from the unmodified +sources by issuing, in a command shell: + + nmake -f makefile.msc + +(you may need to first run the MSVC-provided script VCVARS32.BAT + so as to set up paths to the MSVC tools correctly). + + +VALIDATION + +Correct operation, in the sense that a compressed file can always be +decompressed to reproduce the original, is obviously of paramount +importance. To validate bzip2, I used a modified version of Mark +Nelson's churn program. Churn is an automated test driver which +recursively traverses a directory structure, using bzip2 to compress +and then decompress each file it encounters, and checking that the +decompressed data is the same as the original. + + + +Please read and be aware of the following: + +WARNING: + + This program and library (attempts to) compress data by + performing several non-trivial transformations on it. + Unless you are 100% familiar with *all* the algorithms + contained herein, and with the consequences of modifying them, + you should NOT meddle with the compression or decompression + machinery. Incorrect changes can and very likely *will* + lead to disastrous loss of data. + + +DISCLAIMER: + + I TAKE NO RESPONSIBILITY FOR ANY LOSS OF DATA ARISING FROM THE + USE OF THIS PROGRAM/LIBRARY, HOWSOEVER CAUSED. + + Every compression of a file implies an assumption that the + compressed file can be decompressed to reproduce the original. + Great efforts in design, coding and testing have been made to + ensure that this program works correctly. However, the complexity + of the algorithms, and, in particular, the presence of various + special cases in the code which occur with very low but non-zero + probability make it impossible to rule out the possibility of bugs + remaining in the program. DO NOT COMPRESS ANY DATA WITH THIS + PROGRAM UNLESS YOU ARE PREPARED TO ACCEPT THE POSSIBILITY, HOWEVER + SMALL, THAT THE DATA WILL NOT BE RECOVERABLE. + + That is not to say this program is inherently unreliable. + Indeed, I very much hope the opposite is true. bzip2/libbzip2 + has been carefully constructed and extensively tested. + + +PATENTS: + + To the best of my knowledge, bzip2/libbzip2 does not use any + patented algorithms. However, I do not have the resources + to carry out a patent search. Therefore I cannot give any + guarantee of the above statement. + + + +WHAT'S NEW IN 0.9.0 (as compared to 0.1pl2) ? + + * Approx 10% faster compression, 30% faster decompression + * -t (test mode) is a lot quicker + * Can decompress concatenated compressed files + * Programming interface, so programs can directly read/write .bz2 files + * Less restrictive (BSD-style) licensing + * Flag handling more compatible with GNU gzip + * Much more documentation, i.e., a proper user manual + * Hopefully, improved portability (at least of the library) + +WHAT'S NEW IN 0.9.5 ? + + * Compression speed is much less sensitive to the input + data than in previous versions. Specifically, the very + slow performance caused by repetitive data is fixed. + * Many small improvements in file and flag handling. + * A Y2K statement. + +WHAT'S NEW IN 1.0.x ? + + See the CHANGES file. + +I hope you find bzip2 useful. Feel free to contact the developers at + bzip2-devel@sourceware.org +if you have any suggestions or queries. Many people mailed me with +comments, suggestions and patches after the releases of bzip-0.15, +bzip-0.21, and bzip2 versions 0.1pl2, 0.9.0, 0.9.5, 1.0.0, 1.0.1, +1.0.2 and 1.0.3, and the changes in bzip2 are largely a result of this +feedback. I thank you for your comments. + +bzip2's "home" is https://sourceware.org/bzip2/ + +Julian Seward +jseward@acm.org +Cambridge, UK. + +18 July 1996 (version 0.15) +25 August 1996 (version 0.21) + 7 August 1997 (bzip2, version 0.1) +29 August 1997 (bzip2, version 0.1pl2) +23 August 1998 (bzip2, version 0.9.0) + 8 June 1999 (bzip2, version 0.9.5) + 4 Sept 1999 (bzip2, version 0.9.5d) + 5 May 2000 (bzip2, version 1.0pre8) +30 December 2001 (bzip2, version 1.0.2pre1) +15 February 2005 (bzip2, version 1.0.3) +20 December 2006 (bzip2, version 1.0.4) +10 December 2007 (bzip2, version 1.0.5) + 6 Sept 2010 (bzip2, version 1.0.6) +27 June 2019 (bzip2, version 1.0.7) +13 July 2019 (bzip2, version 1.0.8) |