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Merging upstream version 1.13.

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Signed-off-by: Daniel Baumann <daniel@debian.org>
This commit is contained in:
Daniel Baumann 2025-02-20 21:32:02 +01:00
parent 5c41f945ed
commit 24b3a249d6
Signed by: daniel
GPG key ID: FBB4F0E80A80222F
28 changed files with 803 additions and 720 deletions
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127
encoder.c
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@ -1,5 +1,5 @@
/* Lzlib - Compression library for the lzip format
Copyright (C) 2009-2021 Antonio Diaz Diaz.
Copyright (C) 2009-2022 Antonio Diaz Diaz.
This library is free software. Redistribution and use in source and
binary forms, with or without modification, are permitted provided
@ -21,18 +21,7 @@ static int LZe_get_match_pairs( struct LZ_encoder * const e, struct Pair * pairs
{
int32_t * ptr0 = e->eb.mb.pos_array + ( e->eb.mb.cyclic_pos << 1 );
int32_t * ptr1 = ptr0 + 1;
int32_t * newptr;
int len = 0, len0 = 0, len1 = 0;
int maxlen = 3; /* only used if pairs != 0 */
int num_pairs = 0;
const int pos1 = e->eb.mb.pos + 1;
const int min_pos = ( e->eb.mb.pos > e->eb.mb.dictionary_size ) ?
e->eb.mb.pos - e->eb.mb.dictionary_size : 0;
const uint8_t * const data = Mb_ptr_to_current_pos( &e->eb.mb );
int count, key2, key3, key4, newpos1;
unsigned tmp;
int len_limit = e->match_len_limit;
if( len_limit > Mb_available_bytes( &e->eb.mb ) )
{
e->been_flushed = true;
@ -40,12 +29,18 @@ static int LZe_get_match_pairs( struct LZ_encoder * const e, struct Pair * pairs
if( len_limit < 4 ) { *ptr0 = *ptr1 = 0; return 0; }
}
tmp = crc32[data[0]] ^ data[1];
key2 = tmp & ( num_prev_positions2 - 1 );
int maxlen = 3; /* only used if pairs != 0 */
int num_pairs = 0;
const int min_pos = ( e->eb.mb.pos > e->eb.mb.dictionary_size ) ?
e->eb.mb.pos - e->eb.mb.dictionary_size : 0;
const uint8_t * const data = Mb_ptr_to_current_pos( &e->eb.mb );
unsigned tmp = crc32[data[0]] ^ data[1];
const int key2 = tmp & ( num_prev_positions2 - 1 );
tmp ^= (unsigned)data[2] << 8;
key3 = num_prev_positions2 + ( tmp & ( num_prev_positions3 - 1 ) );
key4 = num_prev_positions2 + num_prev_positions3 +
( ( tmp ^ ( crc32[data[3]] << 5 ) ) & e->eb.mb.key4_mask );
const int key3 = num_prev_positions2 + ( tmp & ( num_prev_positions3 - 1 ) );
const int key4 = num_prev_positions2 + num_prev_positions3 +
( ( tmp ^ ( crc32[data[3]] << 5 ) ) & e->eb.mb.key4_mask );
if( pairs )
{
@ -54,7 +49,7 @@ static int LZe_get_match_pairs( struct LZ_encoder * const e, struct Pair * pairs
if( np2 > min_pos && e->eb.mb.buffer[np2-1] == data[0] )
{
pairs[0].dis = e->eb.mb.pos - np2;
pairs[0].len = maxlen = 2;
pairs[0].len = maxlen = 2 + ( np2 == np3 );
num_pairs = 1;
}
if( np2 != np3 && np3 > min_pos && e->eb.mb.buffer[np3-1] == data[0] )
@ -73,19 +68,22 @@ static int LZe_get_match_pairs( struct LZ_encoder * const e, struct Pair * pairs
}
}
const int pos1 = e->eb.mb.pos + 1;
e->eb.mb.prev_positions[key2] = pos1;
e->eb.mb.prev_positions[key3] = pos1;
newpos1 = e->eb.mb.prev_positions[key4];
int newpos1 = e->eb.mb.prev_positions[key4];
e->eb.mb.prev_positions[key4] = pos1;
int len = 0, len0 = 0, len1 = 0;
int count;
for( count = e->cycles; ; )
{
int delta;
if( newpos1 <= min_pos || --count < 0 ) { *ptr0 = *ptr1 = 0; break; }
if( e->been_flushed ) len = 0;
delta = pos1 - newpos1;
newptr = e->eb.mb.pos_array +
const int delta = pos1 - newpos1;
int32_t * const newptr = e->eb.mb.pos_array +
( ( e->eb.mb.cyclic_pos - delta +
( (e->eb.mb.cyclic_pos >= delta) ? 0 : e->eb.mb.dictionary_size + 1 ) ) << 1 );
if( data[len-delta] == data[len] )
@ -140,7 +138,6 @@ static void LZe_update_distance_prices( struct LZ_encoder * const e )
for( len_state = 0; len_state < len_states; ++len_state )
{
int * const dsp = e->dis_slot_prices[len_state];
int * const dp = e->dis_prices[len_state];
const Bit_model * const bmds = e->eb.bm_dis_slot[len_state];
int slot = 0;
for( ; slot < end_dis_model; ++slot )
@ -149,6 +146,7 @@ static void LZe_update_distance_prices( struct LZ_encoder * const e )
dsp[slot] = price_symbol6( bmds, slot ) +
(((( slot >> 1 ) - 1 ) - dis_align_bits ) << price_shift_bits );
int * const dp = e->dis_prices[len_state];
for( dis = 0; dis < start_dis_model; ++dis )
dp[dis] = dsp[dis];
for( ; dis < modeled_distances; ++dis )
@ -157,7 +155,7 @@ static void LZe_update_distance_prices( struct LZ_encoder * const e )
}
/* Returns the number of bytes advanced (ahead).
/* Return the number of bytes advanced (ahead).
trials[0]..trials[ahead-1] contain the steps to encode.
( trials[0].dis4 == -1 ) means literal.
A match/rep longer or equal than match_len_limit finishes the sequence.
@ -166,9 +164,8 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e,
const int reps[num_rep_distances],
const State state )
{
int main_len, num_pairs, i, rep, num_trials, len;
int rep_index = 0, cur = 0;
int replens[num_rep_distances];
int num_pairs, num_trials;
int i, rep, len;
if( e->pending_num_pairs > 0 ) /* from previous call */
{
@ -177,8 +174,10 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e,
}
else
num_pairs = LZe_read_match_distances( e );
main_len = ( num_pairs > 0 ) ? e->pairs[num_pairs-1].len : 0;
const int main_len = ( num_pairs > 0 ) ? e->pairs[num_pairs-1].len : 0;
int replens[num_rep_distances];
int rep_index = 0;
for( i = 0; i < num_rep_distances; ++i )
{
replens[i] = Mb_true_match_len( &e->eb.mb, 0, reps[i] + 1 );
@ -200,7 +199,6 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e,
return main_len;
}
{
const int pos_state = Mb_data_position( &e->eb.mb ) & pos_state_mask;
const int match_price = price1( e->eb.bm_match[state][pos_state] );
const int rep_match_price = match_price + price1( e->eb.bm_rep[state] );
@ -238,9 +236,8 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e,
for( rep = 0; rep < num_rep_distances; ++rep )
{
int price;
if( replens[rep] < min_match_len ) continue;
price = rep_match_price + LZeb_price_rep( &e->eb, rep, state, pos_state );
const int price = rep_match_price + LZeb_price_rep( &e->eb, rep, state, pos_state );
for( len = min_match_len; len <= replens[rep]; ++len )
Tr_update( &e->trials[len], price +
Lp_price( &e->rep_len_prices, len, pos_state ), rep, 0 );
@ -260,17 +257,10 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e,
if( ++len > e->pairs[i].len && ++i >= num_pairs ) break;
}
}
}
int cur = 0;
while( true ) /* price optimization loop */
{
struct Trial *cur_trial, *next_trial;
int newlen, pos_state, triable_bytes, len_limit;
int start_len = min_match_len;
int next_price, match_price, rep_match_price;
State cur_state;
uint8_t prev_byte, cur_byte, match_byte;
if( !Mb_move_pos( &e->eb.mb ) ) return 0;
if( ++cur >= num_trials ) /* no more initialized trials */
{
@ -278,8 +268,8 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e,
return cur;
}
num_pairs = LZe_read_match_distances( e );
newlen = ( num_pairs > 0 ) ? e->pairs[num_pairs-1].len : 0;
const int num_pairs = LZe_read_match_distances( e );
const int newlen = ( num_pairs > 0 ) ? e->pairs[num_pairs-1].len : 0;
if( newlen >= e->match_len_limit )
{
e->pending_num_pairs = num_pairs;
@ -288,7 +278,8 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e,
}
/* give final values to current trial */
cur_trial = &e->trials[cur];
struct Trial * cur_trial = &e->trials[cur];
State cur_state;
{
const int dis4 = cur_trial->dis4;
int prev_index = cur_trial->prev_index;
@ -319,25 +310,25 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e,
mtf_reps( dis4, cur_trial->reps ); /* literal is ignored */
}
pos_state = Mb_data_position( &e->eb.mb ) & pos_state_mask;
prev_byte = Mb_peek( &e->eb.mb, 1 );
cur_byte = Mb_peek( &e->eb.mb, 0 );
match_byte = Mb_peek( &e->eb.mb, cur_trial->reps[0] + 1 );
const int pos_state = Mb_data_position( &e->eb.mb ) & pos_state_mask;
const uint8_t prev_byte = Mb_peek( &e->eb.mb, 1 );
const uint8_t cur_byte = Mb_peek( &e->eb.mb, 0 );
const uint8_t match_byte = Mb_peek( &e->eb.mb, cur_trial->reps[0] + 1 );
next_price = cur_trial->price +
price0( e->eb.bm_match[cur_state][pos_state] );
int next_price = cur_trial->price +
price0( e->eb.bm_match[cur_state][pos_state] );
if( St_is_char( cur_state ) )
next_price += LZeb_price_literal( &e->eb, prev_byte, cur_byte );
else
next_price += LZeb_price_matched( &e->eb, prev_byte, cur_byte, match_byte );
/* try last updates to next trial */
next_trial = &e->trials[cur+1];
struct Trial * next_trial = &e->trials[cur+1];
Tr_update( next_trial, next_price, -1, cur ); /* literal */
match_price = cur_trial->price + price1( e->eb.bm_match[cur_state][pos_state] );
rep_match_price = match_price + price1( e->eb.bm_rep[cur_state] );
const int match_price = cur_trial->price + price1( e->eb.bm_match[cur_state][pos_state] );
const int rep_match_price = match_price + price1( e->eb.bm_rep[cur_state] );
if( match_byte == cur_byte && next_trial->dis4 != 0 &&
next_trial->prev_index2 == single_step_trial )
@ -352,11 +343,11 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e,
}
}
triable_bytes =
const int triable_bytes =
min( Mb_available_bytes( &e->eb.mb ), max_num_trials - 1 - cur );
if( triable_bytes < min_match_len ) continue;
len_limit = min( e->match_len_limit, triable_bytes );
const int len_limit = min( e->match_len_limit, triable_bytes );
/* try literal + rep0 */
if( match_byte != cur_byte && next_trial->prev_index != cur )
@ -380,19 +371,20 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e,
}
}
int start_len = min_match_len;
/* try rep distances */
for( rep = 0; rep < num_rep_distances; ++rep )
{
const uint8_t * const data = Mb_ptr_to_current_pos( &e->eb.mb );
const int dis = cur_trial->reps[rep] + 1;
int price;
if( data[0-dis] != data[0] || data[1-dis] != data[1] ) continue;
for( len = min_match_len; len < len_limit; ++len )
if( data[len-dis] != data[len] ) break;
while( num_trials < cur + len )
e->trials[++num_trials].price = infinite_price;
price = rep_match_price + LZeb_price_rep( &e->eb, rep, cur_state, pos_state );
int price = rep_match_price + LZeb_price_rep( &e->eb, rep, cur_state, pos_state );
for( i = min_match_len; i <= len; ++i )
Tr_update( &e->trials[cur+i], price +
Lp_price( &e->rep_len_prices, i, pos_state ), rep, cur );
@ -400,17 +392,14 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e,
if( rep == 0 ) start_len = len + 1; /* discard shorter matches */
/* try rep + literal + rep0 */
{
int len2 = len + 1;
const int limit = min( e->match_len_limit + len2, triable_bytes );
int pos_state2;
State state2;
while( len2 < limit && data[len2-dis] == data[len2] ) ++len2;
len2 -= len + 1;
if( len2 < min_match_len ) continue;
pos_state2 = ( pos_state + len ) & pos_state_mask;
state2 = St_set_rep( cur_state );
int pos_state2 = ( pos_state + len ) & pos_state_mask;
State state2 = St_set_rep( cur_state );
price += Lp_price( &e->rep_len_prices, len, pos_state ) +
price0( e->eb.bm_match[state2][pos_state2] ) +
LZeb_price_matched( &e->eb, data[len-1], data[len], data[len-dis] );
@ -423,21 +412,19 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e,
e->trials[++num_trials].price = infinite_price;
Tr_update3( &e->trials[cur+len+1+len2], price, rep, cur + len + 1, cur );
}
}
/* try matches */
if( newlen >= start_len && newlen <= len_limit )
{
int dis;
const int normal_match_price = match_price +
price0( e->eb.bm_rep[cur_state] );
while( num_trials < cur + newlen )
e->trials[++num_trials].price = infinite_price;
i = 0;
int i = 0;
while( e->pairs[i].len < start_len ) ++i;
dis = e->pairs[i].dis;
int dis = e->pairs[i].dis;
for( len = start_len; ; ++len )
{
int price = normal_match_price + LZe_price_pair( e, dis, len, pos_state );
@ -484,7 +471,7 @@ static bool LZe_encode_member( struct LZ_encoder * const e )
const int dis_price_count = best ? 1 : 512;
const int align_price_count = best ? 1 : dis_align_size;
const int price_count = ( e->match_len_limit > 36 ) ? 1013 : 4093;
int ahead, i;
int i;
State * const state = &e->eb.state;
if( e->eb.member_finished ) return true;
@ -494,11 +481,10 @@ static bool LZe_encode_member( struct LZ_encoder * const e )
if( Mb_data_position( &e->eb.mb ) == 0 &&
!Mb_data_finished( &e->eb.mb ) ) /* encode first byte */
{
const uint8_t prev_byte = 0;
uint8_t cur_byte;
if( !Mb_enough_available_bytes( &e->eb.mb ) ||
!Re_enough_free_bytes( &e->eb.renc ) ) return true;
cur_byte = Mb_peek( &e->eb.mb, 0 );
const uint8_t prev_byte = 0;
const uint8_t cur_byte = Mb_peek( &e->eb.mb, 0 );
Re_encode_bit( &e->eb.renc, &e->eb.bm_match[*state][0], 0 );
LZeb_encode_literal( &e->eb, prev_byte, cur_byte );
CRC32_update_byte( &e->eb.crc, cur_byte );
@ -525,7 +511,7 @@ static bool LZe_encode_member( struct LZ_encoder * const e )
Lp_update_prices( &e->rep_len_prices );
}
ahead = LZe_sequence_optimizer( e, e->eb.reps, *state );
int ahead = LZe_sequence_optimizer( e, e->eb.reps, *state );
e->price_counter -= ahead;
for( i = 0; ahead > 0; )
@ -542,14 +528,13 @@ static bool LZe_encode_member( struct LZ_encoder * const e )
const uint8_t prev_byte = Mb_peek( &e->eb.mb, ahead + 1 );
const uint8_t cur_byte = Mb_peek( &e->eb.mb, ahead );
CRC32_update_byte( &e->eb.crc, cur_byte );
if( St_is_char( *state ) )
if( ( *state = St_set_char( *state ) ) < 4 )
LZeb_encode_literal( &e->eb, prev_byte, cur_byte );
else
{
const uint8_t match_byte = Mb_peek( &e->eb.mb, ahead + e->eb.reps[0] + 1 );
LZeb_encode_matched( &e->eb, prev_byte, cur_byte, match_byte );
}
*state = St_set_char( *state );
}
else /* match or repeated match */
{