Adding upstream version 1.23.upstream/1.23upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 300 insertions, 0 deletions

diff --git a/decoder.cc b/decoder.cc
new file mode 100644
index 0000000..345d02b
--- /dev/null
+++ b/decoder.cc
@@ -0,0 +1,300 @@
+/* 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 <cstdio>
+#include <cstdlib>
+#include <cstring>
+#include <string>
+#include <vector>
+#include <stdint.h>
+#include <unistd.h>
+
+#include "lzip.h"
+#include "decoder.h"
+
+
+const CRC32 crc32;
+
+
+/* Return the number of bytes really read.
+   If (value returned < size) and (errno == 0), means EOF was reached.
+*/
+long long readblock( const int fd, uint8_t * const buf, const long long size )
+  {
+  long long sz = 0;
+  errno = 0;
+  while( sz < size )
+    {
+    const int n = read( fd, buf + sz, std::min( 1LL << 20, size - sz ) );
+    if( n > 0 ) sz += n;
+    else if( n == 0 ) break;				// EOF
+    else if( errno != EINTR ) break;
+    errno = 0;
+    }
+  return sz;
+  }
+
+
+/* Return the number of bytes really written.
+   If (value returned < size), it is always an error.
+*/
+long long writeblock( const int fd, const uint8_t * const buf,
+                      const long long size )
+  {
+  long long sz = 0;
+  errno = 0;
+  while( sz < size )
+    {
+    const int n = write( fd, buf + sz, std::min( 1LL << 20, size - sz ) );
+    if( n > 0 ) sz += n;
+    else if( n < 0 && errno != EINTR ) break;
+    errno = 0;
+    }
+  return sz;
+  }
+
+
+bool Range_decoder::read_block()
+  {
+  if( !at_stream_end )
+    {
+    stream_pos = readblock( infd, buffer, buffer_size );
+    if( stream_pos != buffer_size && errno ) throw Error( "Read error" );
+    at_stream_end = ( stream_pos < buffer_size );
+    partial_member_pos += pos;
+    pos = 0;
+    show_dprogress();
+    }
+  return pos < stream_pos;
+  }
+
+
+void LZ_decoder::flush_data()
+  {
+  if( pos > stream_pos )
+    {
+    const int size = pos - stream_pos;
+    crc32.update_buf( crc_, buffer + stream_pos, size );
+    if( outfd >= 0 )
+      {
+      const unsigned long long sp = stream_position();
+      const long long i = positive_diff( outskip, sp );
+      const long long s =
+        std::min( positive_diff( outend, sp ), (unsigned long long)size ) - i;
+      if( s > 0 && writeblock( outfd, buffer + stream_pos + i, s ) != s )
+        throw Error( "Write error" );
+      }
+    if( pos >= dictionary_size )
+      { partial_data_pos += pos; pos = 0; pos_wrapped = true; }
+    stream_pos = pos;
+    }
+  }
+
+
+bool LZ_decoder::verify_trailer( const Pretty_print & pp ) const
+  {
+  Lzip_trailer trailer;
+  int size = rdec.read_data( trailer.data, Lzip_trailer::size );
+  const unsigned long long data_size = data_position();
+  const unsigned long long member_size = rdec.member_position();
+  bool error = false;
+
+  if( size < Lzip_trailer::size )
+    {
+    error = true;
+    if( verbosity >= 0 )
+      {
+      pp();
+      std::fprintf( stderr, "Trailer truncated at trailer position %d;"
+                            " some checks may fail.\n", size );
+      }
+    while( size < Lzip_trailer::size ) trailer.data[size++] = 0;
+    }
+
+  const unsigned td_crc = trailer.data_crc();
+  if( td_crc != crc() )
+    {
+    error = true;
+    if( verbosity >= 0 )
+      {
+      pp();
+      std::fprintf( stderr, "CRC mismatch; stored %08X, computed %08X\n",
+                    td_crc, crc() );
+      }
+    }
+  const unsigned long long td_size = trailer.data_size();
+  if( td_size != data_size )
+    {
+    error = true;
+    if( verbosity >= 0 )
+      {
+      pp();
+      std::fprintf( stderr, "Data size mismatch; stored %llu (0x%llX), computed %llu (0x%llX)\n",
+                    td_size, td_size, data_size, data_size );
+      }
+    }
+  const unsigned long long tm_size = trailer.member_size();
+  if( tm_size != member_size )
+    {
+    error = true;
+    if( verbosity >= 0 )
+      {
+      pp();
+      std::fprintf( stderr, "Member size mismatch; stored %llu (0x%llX), computed %llu (0x%llX)\n",
+                    tm_size, tm_size, member_size, member_size );
+      }
+    }
+  if( error ) return false;
+  if( verbosity >= 2 )
+    {
+    if( verbosity >= 4 ) show_header( dictionary_size );
+    if( data_size == 0 || member_size == 0 )
+      std::fputs( "no data compressed. ", stderr );
+    else
+      std::fprintf( stderr, "%6.3f:1, %5.2f%% ratio, %5.2f%% saved. ",
+                    (double)data_size / member_size,
+                    ( 100.0 * member_size ) / data_size,
+                    100.0 - ( ( 100.0 * member_size ) / data_size ) );
+    if( verbosity >= 4 ) std::fprintf( stderr, "CRC %08X, ", td_crc );
+    if( verbosity >= 3 )
+      std::fprintf( stderr, "%9llu out, %8llu in. ", data_size, member_size );
+    }
+  if( rdec.get_code() != 0 && verbosity >= 1 )
+    {			// corruption in the last 4 bytes of the EOS marker
+    pp();
+    std::fprintf( stderr, "Range decoder final code is %08X\n", rdec.get_code() );
+    }
+  return true;
+  }
+
+
+/* Return value: 0 = OK, 1 = decoder error, 2 = unexpected EOF,
+                 3 = trailer error, 4 = unknown marker found. */
+int LZ_decoder::decode_member( const Pretty_print & pp )
+  {
+  Bit_model bm_literal[1<<literal_context_bits][0x300];
+  Bit_model bm_match[State::states][pos_states];
+  Bit_model bm_rep[State::states];
+  Bit_model bm_rep0[State::states];
+  Bit_model bm_rep1[State::states];
+  Bit_model bm_rep2[State::states];
+  Bit_model bm_len[State::states][pos_states];
+  Bit_model bm_dis_slot[len_states][1<<dis_slot_bits];
+  Bit_model bm_dis[modeled_distances-end_dis_model+1];
+  Bit_model bm_align[dis_align_size];
+  Len_model match_len_model;
+  Len_model rep_len_model;
+  unsigned rep0 = 0;		// rep[0-3] latest four distances
+  unsigned rep1 = 0;		// used for efficient coding of
+  unsigned rep2 = 0;		// repeated distances
+  unsigned rep3 = 0;
+  State state;
+
+  rdec.load();
+  while( !rdec.finished() )
+    {
+    const int pos_state = data_position() & pos_state_mask;
+    if( rdec.decode_bit( bm_match[state()][pos_state] ) == 0 )	// 1st bit
+      {
+      // literal byte
+      Bit_model * const bm = bm_literal[get_lit_state(peek_prev())];
+      if( state.is_char_set_char() )
+        put_byte( rdec.decode_tree8( bm ) );
+      else
+        put_byte( rdec.decode_matched( bm, peek( rep0 ) ) );
+      continue;
+      }
+    // match or repeated match
+    int len;
+    if( rdec.decode_bit( bm_rep[state()] ) != 0 )		// 2nd bit
+      {
+      if( rdec.decode_bit( bm_rep0[state()] ) == 0 )		// 3rd bit
+        {
+        if( rdec.decode_bit( bm_len[state()][pos_state] ) == 0 ) // 4th bit
+          { state.set_short_rep(); put_byte( peek( rep0 ) ); continue; }
+        }
+      else
+        {
+        unsigned distance;
+        if( rdec.decode_bit( bm_rep1[state()] ) == 0 )		// 4th bit
+          distance = rep1;
+        else
+          {
+          if( rdec.decode_bit( bm_rep2[state()] ) == 0 )	// 5th bit
+            distance = rep2;
+          else
+            { distance = rep3; rep3 = rep2; }
+          rep2 = rep1;
+          }
+        rep1 = rep0;
+        rep0 = distance;
+        }
+      state.set_rep();
+      len = rdec.decode_len( rep_len_model, pos_state );
+      }
+    else					// match
+      {
+      len = rdec.decode_len( match_len_model, pos_state );
+      unsigned distance = rdec.decode_tree6( bm_dis_slot[get_len_state(len)] );
+      if( distance >= start_dis_model )
+        {
+        const unsigned dis_slot = distance;
+        const int direct_bits = ( dis_slot >> 1 ) - 1;
+        distance = ( 2 | ( dis_slot & 1 ) ) << direct_bits;
+        if( dis_slot < end_dis_model )
+          distance += rdec.decode_tree_reversed(
+                      bm_dis + ( distance - dis_slot ), direct_bits );
+        else
+          {
+          distance +=
+            rdec.decode( direct_bits - dis_align_bits ) << dis_align_bits;
+          distance += rdec.decode_tree_reversed4( bm_align );
+          if( distance == 0xFFFFFFFFU )		// marker found
+            {
+            rdec.normalize();
+            flush_data();
+            if( len == min_match_len )		// End Of Stream marker
+              {
+              if( verify_trailer( pp ) ) return 0; else return 3;
+              }
+            if( len == min_match_len + 1 )	// Sync Flush marker
+              {
+              rdec.load(); continue;
+              }
+            if( verbosity >= 0 )
+              {
+              pp();
+              std::fprintf( stderr, "Unsupported marker code '%d'\n", len );
+              }
+            return 4;
+            }
+          }
+        }
+      rep3 = rep2; rep2 = rep1; rep1 = rep0; rep0 = distance;
+      state.set_match();
+      if( rep0 >= dictionary_size || ( rep0 >= pos && !pos_wrapped ) )
+        { flush_data(); return 1; }
+      }
+    copy_block( rep0, len );
+    }
+  flush_data();
+  return 2;
+  }