1 files changed, 142 insertions, 0 deletions
diff --git a/split.cc b/split.cc
new file mode 100644
index 0000000..269f051
--- /dev/null
+++ b/split.cc
@@ -0,0 +1,142 @@
+/* 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;
+  }