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+/* Lziprecover - Data recovery tool for the lzip format
+ Copyright (C) 2009-2022 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 <climits>
+#include <cstdio>
+#include <cstring>
+#include <string>
+#include <vector>
+#include <stdint.h>
+#include <unistd.h>
+#include <sys/stat.h>
+
+#include "lzip.h"
+#include "lzip_index.h"
+
+
+namespace {
+
+void first_filename( const std::string & input_filename,
+ const std::string & default_output_filename,
+ const int max_digits )
+ {
+ output_filename = default_output_filename.empty() ?
+ input_filename : default_output_filename;
+ int b = output_filename.size();
+ while( b > 0 && output_filename[b-1] != '/' ) --b;
+ output_filename.insert( b, "rec1" );
+ if( max_digits > 1 ) output_filename.insert( b + 3, max_digits - 1, '0' );
+ }
+
+
+bool next_filename( const int max_digits )
+ {
+ if( verbosity >= 1 )
+ {
+ std::printf( "Member '%s' done \n", output_filename.c_str() );
+ std::fflush( stdout );
+ }
+ int b = output_filename.size();
+ while( b > 0 && output_filename[b-1] != '/' ) --b;
+ for( int i = b + max_digits + 2; i > b + 2; --i ) // "rec<max_digits>"
+ {
+ if( output_filename[i] < '9' ) { ++output_filename[i]; return true; }
+ else output_filename[i] = '0';
+ }
+ return false;
+ }
+
+} // end namespace
+
+
+int split_file( const std::string & input_filename,
+ const std::string & default_output_filename, const bool force )
+ {
+ struct stat in_stats;
+ const int infd =
+ open_instream( input_filename.c_str(), &in_stats, false, true );
+ if( infd < 0 ) return 1;
+
+ Lzip_index lzip_index( infd, true, true, true, true );
+ if( lzip_index.retval() != 0 )
+ {
+ show_file_error( input_filename.c_str(), lzip_index.error().c_str() );
+ return lzip_index.retval();
+ }
+ // verify last member
+ const Block b = lzip_index.mblock( lzip_index.members() - 1 );
+ long long mpos = b.pos();
+ long long msize = b.size();
+ long long failure_pos = 0;
+ if( !safe_seek( infd, mpos ) ) return 1;
+ if( test_member_from_file( infd, msize, &failure_pos ) == 1 )
+ { // corrupt or fake trailer
+ while( true )
+ {
+ mpos += failure_pos; msize -= failure_pos;
+ if( msize < min_member_size ) break; // trailing data
+ if( !safe_seek( infd, mpos ) ) return 1;
+ if( test_member_from_file( infd, msize, &failure_pos ) != 1 ) break;
+ }
+ lzip_index = Lzip_index( infd, true, true, true, true, mpos );
+ if( lzip_index.retval() != 0 )
+ {
+ show_file_error( input_filename.c_str(), lzip_index.error().c_str() );
+ return lzip_index.retval();
+ }
+ }
+
+ if( !safe_seek( infd, 0 ) ) return 1;
+ int max_digits = 1;
+ for( long i = lzip_index.blocks( true ); i >= 10; i /= 10 ) ++max_digits;
+ first_filename( input_filename, default_output_filename, max_digits );
+
+ long long stream_pos = 0; // first pos not yet written to file
+ set_signal_handler();
+ for( long i = 0; i < lzip_index.members(); ++i )
+ {
+ const Block & mb = lzip_index.mblock( i );
+ if( mb.pos() > stream_pos ) // gap
+ {
+ if( !open_outstream( force, true, false, false ) ) return 1;
+ if( !copy_file( infd, outfd, mb.pos() - stream_pos ) ||
+ close_outstream( &in_stats ) != 0 )
+ cleanup_and_fail( 1 );
+ next_filename( max_digits );
+ }
+ if( !open_outstream( force, true, false, false ) ) return 1; // member
+ if( !copy_file( infd, outfd, mb.size() ) ||
+ close_outstream( &in_stats ) != 0 )
+ cleanup_and_fail( 1 );
+ next_filename( max_digits );
+ stream_pos = mb.end();
+ }
+ if( lzip_index.file_size() > stream_pos ) // trailing data
+ {
+ if( !open_outstream( force, true, false, false ) ) return 1;
+ if( !copy_file( infd, outfd, lzip_index.file_size() - stream_pos ) ||
+ close_outstream( &in_stats ) != 0 )
+ cleanup_and_fail( 1 );
+ next_filename( max_digits );
+ }
+ close( infd );
+ return 0;
+ }