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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-14 12:54:40 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-14 12:54:40 +0000
commit47d9004eff8861813477ed571350f7cd83ea4fd4 (patch)
treef909edd49006917e1d3cdae838ca56f5fa7fc9ff /decoder.h
parentInitial commit. (diff)
downloadlunzip-752f3f2cf32e73543411f1d12b2ad0684d507a75.tar.xz
lunzip-752f3f2cf32e73543411f1d12b2ad0684d507a75.zip
Adding upstream version 1.14.upstream/1.14upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'decoder.h')
-rw-r--r--decoder.h397
1 files changed, 397 insertions, 0 deletions
diff --git a/decoder.h b/decoder.h
new file mode 100644
index 0000000..8a948e9
--- /dev/null
+++ b/decoder.h
@@ -0,0 +1,397 @@
+/* Lunzip - Decompressor for the lzip format
+ Copyright (C) 2010-2024 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/>.
+*/
+
+enum { rd_buffer_size = 16384 };
+
+struct Range_decoder
+ {
+ unsigned long long partial_member_pos;
+ uint8_t * buffer; /* input buffer */
+ int pos; /* current pos in buffer */
+ int stream_pos; /* when reached, a new block must be read */
+ uint32_t code;
+ uint32_t range;
+ int infd; /* input file descriptor */
+ bool at_stream_end;
+ };
+
+bool Rd_read_block( struct Range_decoder * const rdec );
+
+static inline bool Rd_init( struct Range_decoder * const rdec, const int ifd )
+ {
+ rdec->partial_member_pos = 0;
+ rdec->buffer = (uint8_t *)malloc( rd_buffer_size );
+ if( !rdec->buffer ) return false;
+ rdec->pos = 0;
+ rdec->stream_pos = 0;
+ rdec->code = 0;
+ rdec->range = 0xFFFFFFFFU;
+ rdec->infd = ifd;
+ rdec->at_stream_end = false;
+ return true;
+ }
+
+static inline void Rd_free( struct Range_decoder * const rdec )
+ { free( rdec->buffer ); }
+
+static inline bool Rd_finished( struct Range_decoder * const rdec )
+ { return rdec->pos >= rdec->stream_pos && !Rd_read_block( rdec ); }
+
+static inline unsigned long long
+Rd_member_position( const struct Range_decoder * const rdec )
+ { return rdec->partial_member_pos + rdec->pos; }
+
+static inline void Rd_reset_member_position( struct Range_decoder * const rdec )
+ { rdec->partial_member_pos = 0; rdec->partial_member_pos -= rdec->pos; }
+
+static inline uint8_t Rd_get_byte( struct Range_decoder * const rdec )
+ {
+ /* 0xFF avoids decoder error if member is truncated at EOS marker */
+ if( Rd_finished( rdec ) ) return 0xFF;
+ return rdec->buffer[rdec->pos++];
+ }
+
+static inline int Rd_read_data( struct Range_decoder * const rdec,
+ uint8_t * const outbuf, const int size )
+ {
+ int sz = 0;
+ while( sz < size && !Rd_finished( rdec ) )
+ {
+ const int rd = min( size - sz, rdec->stream_pos - rdec->pos );
+ memcpy( outbuf + sz, rdec->buffer + rdec->pos, rd );
+ rdec->pos += rd;
+ sz += rd;
+ }
+ return sz;
+ }
+
+static inline bool Rd_load( struct Range_decoder * const rdec,
+ const bool ignore_marking )
+ {
+ int i;
+ rdec->code = 0;
+ rdec->range = 0xFFFFFFFFU;
+ /* check and discard first byte of the LZMA stream */
+ if( Rd_get_byte( rdec ) != 0 && !ignore_marking ) return false;
+ for( i = 0; i < 4; ++i ) rdec->code = (rdec->code << 8) | Rd_get_byte( rdec );
+ return true;
+ }
+
+static inline void Rd_normalize( struct Range_decoder * const rdec )
+ {
+ if( rdec->range <= 0x00FFFFFFU )
+ { rdec->range <<= 8; rdec->code = (rdec->code << 8) | Rd_get_byte( rdec ); }
+ }
+
+static inline unsigned Rd_decode( struct Range_decoder * const rdec,
+ const int num_bits )
+ {
+ unsigned symbol = 0;
+ int i;
+ for( i = num_bits; i > 0; --i )
+ {
+ Rd_normalize( rdec );
+ rdec->range >>= 1;
+/* symbol <<= 1; */
+/* if( rdec->code >= rdec->range ) { rdec->code -= rdec->range; symbol |= 1; } */
+ const bool bit = ( rdec->code >= rdec->range );
+ symbol <<= 1; symbol += bit;
+ rdec->code -= rdec->range & ( 0U - bit );
+ }
+ return symbol;
+ }
+
+static inline unsigned Rd_decode_bit( struct Range_decoder * const rdec,
+ Bit_model * const probability )
+ {
+ Rd_normalize( rdec );
+ const uint32_t bound = ( rdec->range >> bit_model_total_bits ) * *probability;
+ if( rdec->code < bound )
+ {
+ rdec->range = bound;
+ *probability += ( bit_model_total - *probability ) >> bit_model_move_bits;
+ return 0;
+ }
+ else
+ {
+ rdec->code -= bound;
+ rdec->range -= bound;
+ *probability -= *probability >> bit_model_move_bits;
+ return 1;
+ }
+ }
+
+static inline void Rd_decode_symbol_bit( struct Range_decoder * const rdec,
+ Bit_model * const probability, unsigned * symbol )
+ {
+ Rd_normalize( rdec );
+ *symbol <<= 1;
+ const uint32_t bound = ( rdec->range >> bit_model_total_bits ) * *probability;
+ if( rdec->code < bound )
+ {
+ rdec->range = bound;
+ *probability += ( bit_model_total - *probability ) >> bit_model_move_bits;
+ }
+ else
+ {
+ rdec->code -= bound;
+ rdec->range -= bound;
+ *probability -= *probability >> bit_model_move_bits;
+ *symbol |= 1;
+ }
+ }
+
+static inline void Rd_decode_symbol_bit_reversed( struct Range_decoder * const rdec,
+ Bit_model * const probability, unsigned * model,
+ unsigned * symbol, const int i )
+ {
+ Rd_normalize( rdec );
+ *model <<= 1;
+ const uint32_t bound = ( rdec->range >> bit_model_total_bits ) * *probability;
+ if( rdec->code < bound )
+ {
+ rdec->range = bound;
+ *probability += ( bit_model_total - *probability ) >> bit_model_move_bits;
+ }
+ else
+ {
+ rdec->code -= bound;
+ rdec->range -= bound;
+ *probability -= *probability >> bit_model_move_bits;
+ *model |= 1;
+ *symbol |= 1 << i;
+ }
+ }
+
+static inline unsigned Rd_decode_tree6( struct Range_decoder * const rdec,
+ Bit_model bm[] )
+ {
+ unsigned symbol = 1;
+ Rd_decode_symbol_bit( rdec, &bm[symbol], &symbol );
+ Rd_decode_symbol_bit( rdec, &bm[symbol], &symbol );
+ Rd_decode_symbol_bit( rdec, &bm[symbol], &symbol );
+ Rd_decode_symbol_bit( rdec, &bm[symbol], &symbol );
+ Rd_decode_symbol_bit( rdec, &bm[symbol], &symbol );
+ Rd_decode_symbol_bit( rdec, &bm[symbol], &symbol );
+ return symbol & 0x3F;
+ }
+
+static inline unsigned Rd_decode_tree8( struct Range_decoder * const rdec,
+ Bit_model bm[] )
+ {
+ unsigned symbol = 1;
+ Rd_decode_symbol_bit( rdec, &bm[symbol], &symbol );
+ Rd_decode_symbol_bit( rdec, &bm[symbol], &symbol );
+ Rd_decode_symbol_bit( rdec, &bm[symbol], &symbol );
+ Rd_decode_symbol_bit( rdec, &bm[symbol], &symbol );
+ Rd_decode_symbol_bit( rdec, &bm[symbol], &symbol );
+ Rd_decode_symbol_bit( rdec, &bm[symbol], &symbol );
+ Rd_decode_symbol_bit( rdec, &bm[symbol], &symbol );
+ Rd_decode_symbol_bit( rdec, &bm[symbol], &symbol );
+ return symbol & 0xFF;
+ }
+
+static inline unsigned
+Rd_decode_tree_reversed( struct Range_decoder * const rdec,
+ Bit_model bm[], const int num_bits )
+ {
+ unsigned model = 1;
+ unsigned symbol = 0;
+ int i;
+ for( i = 0; i < num_bits; ++i )
+ Rd_decode_symbol_bit_reversed( rdec, &bm[model], &model, &symbol, i );
+ return symbol;
+ }
+
+static inline unsigned
+Rd_decode_tree_reversed4( struct Range_decoder * const rdec, Bit_model bm[] )
+ {
+ unsigned model = 1;
+ unsigned symbol = 0;
+ Rd_decode_symbol_bit_reversed( rdec, &bm[model], &model, &symbol, 0 );
+ Rd_decode_symbol_bit_reversed( rdec, &bm[model], &model, &symbol, 1 );
+ Rd_decode_symbol_bit_reversed( rdec, &bm[model], &model, &symbol, 2 );
+ Rd_decode_symbol_bit_reversed( rdec, &bm[model], &model, &symbol, 3 );
+ return symbol;
+ }
+
+static inline unsigned Rd_decode_matched( struct Range_decoder * const rdec,
+ Bit_model bm[], unsigned match_byte )
+ {
+ unsigned symbol = 1;
+ unsigned mask = 0x100;
+ while( true )
+ {
+ const unsigned match_bit = ( match_byte <<= 1 ) & mask;
+ const unsigned bit = Rd_decode_bit( rdec, &bm[symbol+match_bit+mask] );
+ symbol <<= 1; symbol += bit;
+ if( symbol > 0xFF ) return symbol & 0xFF;
+ mask &= ~(match_bit ^ (bit << 8)); /* if( match_bit != bit ) mask = 0; */
+ }
+ }
+
+static inline unsigned Rd_decode_len( struct Range_decoder * const rdec,
+ struct Len_model * const lm,
+ const int pos_state )
+ {
+ Bit_model * bm;
+ unsigned mask, offset, symbol = 1;
+
+ if( Rd_decode_bit( rdec, &lm->choice1 ) == 0 )
+ { bm = lm->bm_low[pos_state]; mask = 7; offset = 0; goto len3; }
+ if( Rd_decode_bit( rdec, &lm->choice2 ) == 0 )
+ { bm = lm->bm_mid[pos_state]; mask = 7; offset = len_low_symbols; goto len3; }
+ bm = lm->bm_high; mask = 0xFF; offset = len_low_symbols + len_mid_symbols;
+ Rd_decode_symbol_bit( rdec, &bm[symbol], &symbol );
+ Rd_decode_symbol_bit( rdec, &bm[symbol], &symbol );
+ Rd_decode_symbol_bit( rdec, &bm[symbol], &symbol );
+ Rd_decode_symbol_bit( rdec, &bm[symbol], &symbol );
+ Rd_decode_symbol_bit( rdec, &bm[symbol], &symbol );
+len3:
+ Rd_decode_symbol_bit( rdec, &bm[symbol], &symbol );
+ Rd_decode_symbol_bit( rdec, &bm[symbol], &symbol );
+ Rd_decode_symbol_bit( rdec, &bm[symbol], &symbol );
+ return ( symbol & mask ) + min_match_len + offset;
+ }
+
+
+struct LZ_decoder
+ {
+ unsigned long long partial_data_pos;
+ struct Range_decoder * rdec;
+ unsigned dictionary_size;
+ unsigned buffer_size;
+ uint8_t * buffer; /* output buffer */
+ unsigned pos; /* current pos in buffer */
+ unsigned stream_pos; /* first byte not yet written to file */
+ uint32_t crc;
+ int outfd; /* output file descriptor */
+ bool pos_wrapped;
+ };
+
+void LZd_flush_data( struct LZ_decoder * const d );
+
+unsigned seek_read_back( const int fd, uint8_t * const buf, const int size,
+ const int offset );
+
+static inline uint8_t LZd_peek_prev( const struct LZ_decoder * const d )
+ { return d->buffer[((d->pos > 0) ? d->pos : d->buffer_size)-1]; }
+
+static inline uint8_t LZd_peek( const struct LZ_decoder * const d,
+ const unsigned distance )
+ {
+ uint8_t b;
+ if( d->pos > distance ) b = d->buffer[d->pos-distance-1];
+ else if( d->buffer_size > distance )
+ b = d->buffer[d->buffer_size+d->pos-distance-1];
+ else if( seek_read_back( d->outfd, &b, 1,
+ distance + 1 + d->stream_pos - d->pos ) != 1 )
+ { show_error( "Seek error", errno, false ); cleanup_and_fail( 1 ); }
+ return b;
+ }
+
+static inline void LZd_put_byte( struct LZ_decoder * const d, const uint8_t b )
+ {
+ d->buffer[d->pos] = b;
+ if( ++d->pos >= d->buffer_size ) LZd_flush_data( d );
+ }
+
+static inline void LZd_copy_block( struct LZ_decoder * const d,
+ const unsigned distance, unsigned len )
+ {
+ unsigned lpos = d->pos, i = lpos - distance - 1;
+ bool fast, fast2;
+ if( lpos > distance )
+ {
+ fast = ( len < d->buffer_size - lpos );
+ fast2 = ( fast && len <= lpos - i );
+ }
+ else
+ {
+ i += d->buffer_size;
+ fast = ( len < d->buffer_size - i ); /* (i == pos) may happen */
+ fast2 = ( fast && len <= i - lpos );
+ }
+ if( fast ) /* no wrap */
+ {
+ d->pos += len;
+ if( fast2 ) /* no wrap, no overlap */
+ memcpy( d->buffer + lpos, d->buffer + i, len );
+ else
+ for( ; len > 0; --len ) d->buffer[lpos++] = d->buffer[i++];
+ }
+ else for( ; len > 0; --len )
+ {
+ d->buffer[d->pos] = d->buffer[i];
+ if( ++d->pos >= d->buffer_size ) LZd_flush_data( d );
+ if( ++i >= d->buffer_size ) i = 0;
+ }
+ }
+
+/* block is (at least partially) outside of the buffer */
+static inline void LZd_copy_block2( struct LZ_decoder * const d,
+ const unsigned distance, unsigned len )
+ {
+ if( len < d->buffer_size - d->pos ) /* no wrap */
+ {
+ const unsigned offset = distance + 1 + d->stream_pos - d->pos;
+ if( len <= offset ) /* block is in file */
+ {
+ if( seek_read_back( d->outfd, d->buffer + d->pos, len, offset ) != len )
+ { show_error( "Seek error", errno, false ); cleanup_and_fail( 1 ); }
+ d->pos += len;
+ return;
+ }
+ }
+ for( ; len > 0; --len )
+ LZd_put_byte( d, LZd_peek( d, distance ) );
+ }
+
+static inline bool LZd_init( struct LZ_decoder * const d,
+ struct Range_decoder * const rde,
+ const unsigned buffer_size,
+ const unsigned dict_size, const int ofd )
+ {
+ d->partial_data_pos = 0;
+ d->rdec = rde;
+ d->dictionary_size = dict_size;
+ d->buffer_size = min( buffer_size, dict_size );
+ d->buffer = (uint8_t *)malloc( d->buffer_size );
+ if( !d->buffer ) return false;
+ d->pos = 0;
+ d->stream_pos = 0;
+ d->crc = 0xFFFFFFFFU;
+ d->outfd = ofd;
+ d->pos_wrapped = false;
+ /* prev_byte of first byte; also for LZd_peek( 0 ) on corrupt file */
+ d->buffer[d->buffer_size-1] = 0;
+ return true;
+ }
+
+static inline void LZd_free( struct LZ_decoder * const d )
+ { free( d->buffer ); }
+
+static inline unsigned LZd_crc( const struct LZ_decoder * const d )
+ { return d->crc ^ 0xFFFFFFFFU; }
+
+static inline unsigned long long
+LZd_data_position( const struct LZ_decoder * const d )
+ { return d->partial_data_pos + d->pos; }
+
+int LZd_decode_member( struct LZ_decoder * const d,
+ const struct Cl_options * const cl_opts,
+ struct Pretty_print * const pp );