From de466aac7b9c2010f3393470cc4825c2dfb0cc54 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 May 2017 17:51:58 +0200 Subject: Merging upstream version 1.19. Signed-off-by: Daniel Baumann --- file_index.cc | 192 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 192 insertions(+) create mode 100644 file_index.cc (limited to 'file_index.cc') diff --git a/file_index.cc b/file_index.cc new file mode 100644 index 0000000..4a1759c --- /dev/null +++ b/file_index.cc @@ -0,0 +1,192 @@ +/* Lzip - LZMA lossless data compressor + Copyright (C) 2008-2017 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 "file_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 + + +void File_index::set_errno_error( const char * const msg ) + { + error_ = msg; error_ += std::strerror( errno ); + retval_ = 1; + } + +void File_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; + } + + +// If successful, push last member and set pos to member header. +bool File_index::skip_trailing_data( const int fd, long long & pos ) + { + enum { block_size = 16384, + buffer_size = block_size + File_trailer::size - 1 + File_header::size }; + uint8_t buffer[buffer_size]; + if( pos < min_member_size ) return false; + 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 >= File_trailer::size; --i ) + if( buffer[i-1] <= max_msb ) // most significant byte of member_size + { + File_trailer & trailer = + *(File_trailer *)( buffer + i - File_trailer::size ); + const unsigned long long member_size = trailer.member_size(); + if( member_size == 0 ) + { while( i > File_trailer::size && buffer[i-9] == 0 ) --i; continue; } + if( member_size < min_member_size || member_size > ipos + i ) + continue; + File_header header; + if( seek_read( fd, header.data, File_header::size, + ipos + i - member_size ) != File_header::size ) + { set_errno_error( "Error reading member header: " ); return false; } + const unsigned dictionary_size = header.dictionary_size(); + if( !header.verify_magic() || !header.verify_version() || + !isvalid_ds( dictionary_size ) ) continue; + if( (*(File_header *)( buffer + i )).verify_prefix( bsize - i ) ) + { + error_ = "Last member in input file is truncated or corrupt."; + retval_ = 2; return false; + } + pos = ipos + i - member_size; + member_vector.push_back( Member( 0, trailer.data_size(), pos, + member_size, dictionary_size ) ); + return true; + } + if( ipos <= 0 ) + { set_num_error( "Member size in trailer is corrupt at pos ", pos - 8 ); + return false; } + bsize = buffer_size; + search_size = bsize - File_header::size; + rd_size = block_size; + ipos -= rd_size; + std::memcpy( buffer + rd_size, buffer, buffer_size - rd_size ); + } + } + + +File_index::File_index( const int infd, const bool ignore_trailing ) + : isize( lseek( infd, 0, SEEK_END ) ), retval_( 0 ) + { + if( isize < 0 ) + { set_errno_error( "Input file is not seekable: " ); return; } + if( isize < min_member_size ) + { error_ = "Input file is too short."; retval_ = 2; return; } + if( isize > INT64_MAX ) + { error_ = "Input file is too long (2^63 bytes or more)."; + retval_ = 2; return; } + + File_header header; + if( seek_read( infd, header.data, File_header::size, 0 ) != File_header::size ) + { set_errno_error( "Error reading member header: " ); return; } + if( !header.verify_magic() ) + { error_ = bad_magic_msg; retval_ = 2; return; } + if( !header.verify_version() ) + { error_ = bad_version( header.version() ); retval_ = 2; return; } + if( !isvalid_ds( header.dictionary_size() ) ) + { error_ = bad_dict_msg; retval_ = 2; return; } + + long long pos = isize; // always points to a header or to EOF + while( pos >= min_member_size ) + { + File_trailer trailer; + if( seek_read( infd, trailer.data, File_trailer::size, + pos - File_trailer::size ) != File_trailer::size ) + { set_errno_error( "Error reading member trailer: " ); break; } + const unsigned long long member_size = trailer.member_size(); + if( member_size < min_member_size || member_size > (unsigned long long)pos ) + { + if( !member_vector.empty() ) + set_num_error( "Member size in trailer is corrupt at pos ", pos - 8 ); + else if( skip_trailing_data( infd, pos ) ) + { if( ignore_trailing ) continue; + error_ = trailing_msg; retval_ = 2; return; } + break; + } + if( seek_read( infd, header.data, File_header::size, + pos - member_size ) != File_header::size ) + { set_errno_error( "Error reading member header: " ); break; } + const unsigned dictionary_size = header.dictionary_size(); + if( !header.verify_magic() || !header.verify_version() || + !isvalid_ds( dictionary_size ) ) + { + if( !member_vector.empty() ) + set_num_error( "Bad header at pos ", pos - member_size ); + else if( skip_trailing_data( infd, pos ) ) + { if( ignore_trailing ) continue; + error_ = trailing_msg; retval_ = 2; return; } + break; + } + pos -= member_size; + member_vector.push_back( Member( 0, trailer.data_size(), pos, + member_size, dictionary_size ) ); + } + if( pos != 0 || member_vector.empty() ) + { + 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 < member_vector.size() - 1; ++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; + } + member_vector[i+1].dblock.pos( end ); + } + } -- cgit v1.2.3