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Diffstat (limited to '')
| -rw-r--r-- | dump_remove.cc | 365 |
1 files changed, 365 insertions, 0 deletions
diff --git a/dump_remove.cc b/dump_remove.cc new file mode 100644 index 0000000..3273303 --- /dev/null +++ b/dump_remove.cc @@ -0,0 +1,365 @@ +/* Lziprecover - Data recovery tool for the lzip format + Copyright (C) 2009-2024 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 <http://www.gnu.org/licenses/>. +*/ + +#define _FILE_OFFSET_BITS 64 + +#include <algorithm> +#include <cerrno> +#include <cstdio> +#include <cstring> +#include <string> +#include <vector> +#include <stdint.h> +#include <unistd.h> +#include <utime.h> +#include <sys/stat.h> + +#include "lzip.h" +#include "lzip_index.h" + + +const char * const pdate_msg = "warning: can't preserve file date"; + + +/* If strip is false, dump to outfd members/gaps/tdata in member_list. + If strip is true, dump to outfd members/gaps/tdata not in member_list. */ +int dump_members( const std::vector< std::string > & filenames, + const std::string & default_output_filename, + const Cl_options & cl_opts, const Member_list & member_list, + const bool force, const bool strip, const bool to_stdout ) + { + if( to_stdout || default_output_filename.empty() ) outfd = STDOUT_FILENO; + else + { + output_filename = default_output_filename; + set_signal_handler(); + if( !open_outstream( force, false, false, false ) ) return 1; + } + if( ( strip || !member_list.tdata || member_list.damaged || + member_list.empty || member_list.range() ) && + !check_tty_out() ) return 1; // check tty except for --dump=tdata + unsigned long long copied_size = 0, stripped_size = 0; + unsigned long long copied_tsize = 0, stripped_tsize = 0; + long members = 0, smembers = 0; + int files = 0, tfiles = 0, retval = 0; + 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, cl_opts.ignore_errors, + cl_opts.ignore_errors ); + if( lzip_index.retval() != 0 ) + { + show_file_error( input_filename, lzip_index.error().c_str() ); + set_retval( retval, lzip_index.retval() ); + close( infd ); + continue; + } + if( !safe_seek( infd, 0, input_filename ) ) cleanup_and_fail( 1 ); + const long blocks = lzip_index.blocks( false ); // not counting tdata + long long stream_pos = 0; // first pos not yet read from file + long gaps = 0; + const long prev_members = members, prev_smembers = smembers; + const unsigned long long prev_stripped_size = stripped_size; + for( long j = 0; j < lzip_index.members(); ++j ) // copy members and gaps + { + const Block & mb = lzip_index.mblock( j ); + if( mb.pos() > stream_pos ) // gap + { + const bool in = member_list.damaged || + member_list.includes( j + gaps, blocks ); + if( in == !strip ) + { + if( !safe_seek( infd, stream_pos, input_filename ) || + !copy_file( infd, outfd, mb.pos() - stream_pos ) ) + cleanup_and_fail( 1 ); + copied_size += mb.pos() - stream_pos; ++members; + } + else { stripped_size += mb.pos() - stream_pos; ++smembers; } + ++gaps; + } + bool in = member_list.includes( j + gaps, blocks ); // member + if( !in && member_list.empty && lzip_index.dblock( j ).size() == 0 ) + in = true; + if( !in && member_list.damaged ) + { + if( !safe_seek( infd, mb.pos(), input_filename ) ) cleanup_and_fail( 1 ); + in = ( test_member_from_file( infd, mb.size() ) != 0 ); // damaged + } + if( in == !strip ) + { + if( !safe_seek( infd, mb.pos(), input_filename ) || + !copy_file( infd, outfd, mb.size() ) ) cleanup_and_fail( 1 ); + copied_size += mb.size(); ++members; + } + else { stripped_size += mb.size(); ++smembers; } + stream_pos = mb.end(); + } + if( strip && members == prev_members ) // all members were stripped + { if( verbosity >= 1 ) + show_file_error( input_filename, "All members stripped, skipping." ); + stripped_size = prev_stripped_size; smembers = prev_smembers; + close( infd ); continue; } + if( ( !strip && members > prev_members ) || + ( strip && smembers > prev_smembers ) ) ++files; + // copy trailing data + const unsigned long long cdata_size = lzip_index.cdata_size(); + const long long trailing_size = lzip_index.file_size() - cdata_size; + if( member_list.tdata == !strip && trailing_size > 0 && + ( !strip || i + 1 >= filenames.size() ) ) // strip all but last + { + if( !safe_seek( infd, cdata_size, input_filename ) || + !copy_file( infd, outfd, trailing_size ) ) cleanup_and_fail( 1 ); + copied_tsize += trailing_size; + } + else if( trailing_size > 0 ) { stripped_tsize += trailing_size; ++tfiles; } + close( infd ); + } + if( !close_outstream( 0 ) ) set_retval( retval, 1 ); + if( verbosity >= 1 ) + { + if( !strip ) + { + if( member_list.damaged || member_list.empty || member_list.range() ) + std::fprintf( stderr, "%llu bytes dumped from %ld %s from %d %s.\n", + copied_size, + members, ( members == 1 ) ? "member" : "members", + files, ( files == 1 ) ? "file" : "files" ); + if( member_list.tdata ) + std::fprintf( stderr, "%llu trailing bytes dumped.\n", copied_tsize ); + } + else + { + if( member_list.damaged || member_list.empty || member_list.range() ) + std::fprintf( stderr, "%llu bytes stripped from %ld %s from %d %s.\n", + stripped_size, + smembers, ( smembers == 1 ) ? "member" : "members", + files, ( files == 1 ) ? "file" : "files" ); + if( member_list.tdata ) + std::fprintf( stderr, "%llu trailing bytes stripped from %d %s.\n", + stripped_tsize, tfiles, ( tfiles == 1 ) ? "file" : "files" ); + } + } + return retval; + } + + +/* Remove members, tdata from files in place by opening two descriptors for + each file. */ +int remove_members( const std::vector< std::string > & filenames, + const Cl_options & cl_opts, const Member_list & member_list ) + { + unsigned long long removed_size = 0, removed_tsize = 0; + long members = 0; + int files = 0, tfiles = 0, retval = 0; + for( unsigned i = 0; i < filenames.size(); ++i ) + { + const char * const filename = filenames[i].c_str(); + struct stat in_stats, dummy_stats; + const int infd = open_instream( filename, &in_stats, false, true ); + if( infd < 0 ) { set_retval( retval, 1 ); continue; } + + const Lzip_index lzip_index( infd, cl_opts, cl_opts.ignore_errors, + cl_opts.ignore_errors ); + if( lzip_index.retval() != 0 ) + { + show_file_error( filename, lzip_index.error().c_str() ); + set_retval( retval, lzip_index.retval() ); + close( infd ); + continue; + } + const int fd = open_truncable_stream( filename, &dummy_stats ); + if( fd < 0 ) { close( infd ); set_retval( retval, 1 ); continue; } + + if( !safe_seek( infd, 0, filename ) ) return 1; + const long blocks = lzip_index.blocks( false ); // not counting tdata + long long stream_pos = 0; // first pos not yet written to file + long gaps = 0; + bool error = false; + const long prev_members = members; + for( long j = 0; j < lzip_index.members(); ++j ) // copy members and gaps + { + const Block & mb = lzip_index.mblock( j ); + const long long prev_end = (j > 0) ? lzip_index.mblock(j - 1).end() : 0; + if( mb.pos() > prev_end ) // gap + { + if( !member_list.damaged && !member_list.includes( j + gaps, blocks ) ) + { + if( stream_pos != prev_end && + ( !safe_seek( infd, prev_end, filename ) || + !safe_seek( fd, stream_pos, filename ) || + !copy_file( infd, fd, mb.pos() - prev_end ) ) ) + { error = true; set_retval( retval, 1 ); break; } + stream_pos += mb.pos() - prev_end; + } + else ++members; + ++gaps; + } + bool in = member_list.includes( j + gaps, blocks ); // member + if( !in && member_list.empty && lzip_index.dblock( j ).size() == 0 ) + in = true; + if( !in && member_list.damaged ) + { + if( !safe_seek( infd, mb.pos(), filename ) ) + { error = true; set_retval( retval, 1 ); break; } + in = ( test_member_from_file( infd, mb.size() ) != 0 ); // damaged + } + if( !in ) + { + if( stream_pos != mb.pos() && + ( !safe_seek( infd, mb.pos(), filename ) || + !safe_seek( fd, stream_pos, filename ) || + !copy_file( infd, fd, mb.size() ) ) ) + { error = true; set_retval( retval, 1 ); break; } + stream_pos += mb.size(); + } + else ++members; + } + if( error ) { close( fd ); close( infd ); break; } + if( stream_pos == 0 ) // all members were removed + { show_file_error( filename, "All members would be removed, skipping." ); + close( fd ); close( infd ); set_retval( retval, 2 ); + members = prev_members; continue; } + const long long cdata_size = lzip_index.cdata_size(); + if( cdata_size > stream_pos ) + { removed_size += cdata_size - stream_pos; ++files; } + const long long file_size = lzip_index.file_size(); + const long long trailing_size = file_size - cdata_size; + if( trailing_size > 0 ) + { + if( !member_list.tdata ) // copy trailing data + { + if( stream_pos != cdata_size && + ( !safe_seek( infd, cdata_size, filename ) || + !safe_seek( fd, stream_pos, filename ) || + !copy_file( infd, fd, trailing_size ) ) ) + { close( fd ); close( infd ); set_retval( retval, 1 ); break; } + stream_pos += trailing_size; + } + else { removed_tsize += trailing_size; ++tfiles; } + } + if( stream_pos >= file_size ) // no members were removed + { close( fd ); close( infd ); continue; } + int result; + do result = ftruncate( fd, stream_pos ); + while( result != 0 && errno == EINTR ); + if( result != 0 ) + { + show_file_error( filename, "Can't truncate file", errno ); + close( fd ); close( infd ); set_retval( retval, 1 ); break; + } + if( close( fd ) != 0 || close( infd ) != 0 ) + { + show_file_error( filename, "Error closing file", errno ); + set_retval( retval, 1 ); break; + } + struct utimbuf t; + t.actime = in_stats.st_atime; + t.modtime = in_stats.st_mtime; + if( utime( filename, &t ) != 0 && verbosity >= 1 ) + show_file_error( filename, pdate_msg, errno ); + } + if( verbosity >= 1 ) + { + if( member_list.damaged || member_list.empty || member_list.range() ) + std::fprintf( stderr, "%llu bytes removed from %ld %s from %d %s.\n", + removed_size, + members, ( members == 1 ) ? "member" : "members", + files, ( files == 1 ) ? "file" : "files" ); + if( member_list.tdata ) + std::fprintf( stderr, "%llu trailing bytes removed from %d %s.\n", + removed_tsize, tfiles, ( tfiles == 1 ) ? "file" : "files" ); + } + return retval; + } + + +/* Set to zero in place the first LZMA byte of each member in each file by + opening one rw descriptor for each file. */ +int clear_marking( const std::vector< std::string > & filenames, + const Cl_options & cl_opts ) + { + long cleared_members = 0; + int files = 0, retval = 0; + for( unsigned i = 0; i < filenames.size(); ++i ) + { + const char * const filename = filenames[i].c_str(); + struct stat in_stats; + const int fd = open_truncable_stream( filename, &in_stats ); + if( fd < 0 ) { set_retval( retval, 1 ); continue; } + + const Lzip_index lzip_index( fd, cl_opts, cl_opts.ignore_errors, + cl_opts.ignore_errors ); + if( lzip_index.retval() != 0 ) + { + show_file_error( filename, lzip_index.error().c_str() ); + set_retval( retval, lzip_index.retval() ); + close( fd ); + continue; + } + + enum { bufsize = Lzip_header::size + 1 }; + uint8_t header_buf[bufsize]; + const uint8_t * const p = header_buf; // keep gcc 6.1.0 quiet + const Lzip_header & header = *(const Lzip_header *)p; + uint8_t * const mark = header_buf + header.size; + bool write_attempted = false; + for( long j = 0; j < lzip_index.members(); ++j ) // clear the members + { + const Block & mb = lzip_index.mblock( j ); + if( seek_read( fd, header_buf, bufsize, mb.pos() ) != bufsize ) + { show_file_error( filename, "Error reading member header", errno ); + set_retval( retval, 1 ); break; } + if( !header.check( cl_opts.ignore_errors ) ) + { show_file_error( filename, "Member header became corrupt as we read it." ); + set_retval( retval, 2 ); break; } + if( *mark == 0 ) continue; + *mark = 0; write_attempted = true; + if( seek_write( fd, mark, 1, mb.pos() + header.size ) != 1 ) + { show_file_error( filename, "Error writing to file", errno ); + set_retval( retval, 1 ); break; } + ++cleared_members; + } + if( close( fd ) != 0 ) + { + show_file_error( filename, "Error closing file", errno ); + set_retval( retval, 1 ); break; + } + if( write_attempted ) + { + struct utimbuf t; + t.actime = in_stats.st_atime; + t.modtime = in_stats.st_mtime; + if( utime( filename, &t ) != 0 && verbosity >= 1 ) + show_file_error( filename, pdate_msg, errno ); + ++files; + } + } + if( verbosity >= 1 ) + std::fprintf( stderr, "%lu %s cleared in %d %s.\n", cleared_members, + ( cleared_members == 1 ) ? "member" : "members", + files, ( files == 1 ) ? "file" : "files" ); + return retval; + } |