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Code Issues Releases Wiki Activity

Miscellaneous LZ and LZMA encoder cleanups

This commit is contained in:
Lasse Collin 2008-09-17 22:11:39 +03:00
parent 13d68b0698
commit f147666a5c
5 changed files with 29 additions and 117 deletions
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14
src/liblzma/api/lzma/lzma.h
View File

@ -38,13 +38,6 @@
* Usually hash chains are faster than binary trees.
*/
typedef enum {
LZMA_MF_INVALID = -1,
/**<
* \brief Invalid match finder ID
*
* Used as array terminator in lzma_available_match_finders.
*/
LZMA_MF_HC3 = 0x03,
/**<
* \brief Hash Chain with 3 bytes hashing
@ -121,13 +114,6 @@ extern lzma_bool lzma_mf_is_supported(lzma_match_finder match_finder)
* finder.
*/
typedef enum {
LZMA_MODE_INVALID = -1,
/**<
* \brief Invalid mode
*
* Used as array terminator in lzma_available_modes.
*/
LZMA_MODE_FAST = 0,
/**<
* \brief Fast compression

8
src/liblzma/lz/lz_encoder.c
View File

@ -288,8 +288,12 @@ lz_encoder_prepare(lzma_mf *mf, lzma_allocator *allocator,
return true;
}
// Calculate the sizes of mf->hash and mf->son.
// Calculate the sizes of mf->hash and mf->son and check that
// find_len_max is big enough for the selected match finder.
const uint32_t hash_bytes = lz_options->match_finder & 0x0F;
if (hash_bytes > mf->find_len_max)
return true;
const bool is_bt = (lz_options->match_finder & 0x10) != 0;
uint32_t hs;
@ -351,7 +355,7 @@ lz_encoder_prepare(lzma_mf *mf, lzma_allocator *allocator,
// Maximum number of match finder cycles
mf->loops = lz_options->match_finder_cycles;
if (mf->loops == 0) {
mf->loops = 16 + (lz_options->find_len_max / 2);
mf->loops = 16 + (mf->find_len_max / 2);
if (!is_bt)
mf->loops /= 2;
}

1
src/liblzma/lzma/Makefile.am
View File

@ -31,7 +31,6 @@ liblzma2_la_SOURCES += \
lzma_encoder.c \
lzma_encoder_presets.c \
lzma_encoder_private.h \
lzma_encoder_features.c \
lzma_encoder_optimum_fast.c \
lzma_encoder_optimum_normal.c

64
src/liblzma/lzma/lzma_encoder.c
View File

@ -422,16 +422,11 @@ lzma_encode(lzma_coder *restrict coder, lzma_mf *restrict mf,
// Initialization //
////////////////////
static bool
static void
set_lz_options(lzma_lz_options *lz_options, const lzma_options_lzma *options)
{
if (!is_lclppb_valid(options)
|| options->fast_bytes < LZMA_FAST_BYTES_MIN
|| options->fast_bytes > LZMA_FAST_BYTES_MAX)
return true;
// FIXME validation
// LZ encoder initialization does the validation, also when just
// calculating memory usage, so we don't need to validate here.
lz_options->before_size = OPTS;
lz_options->dictionary_size = options->dictionary_size;
lz_options->after_size = LOOP_INPUT_MAX;
@ -441,8 +436,6 @@ set_lz_options(lzma_lz_options *lz_options, const lzma_options_lzma *options)
lz_options->match_finder_cycles = options->match_finder_cycles;
lz_options->preset_dictionary = options->preset_dictionary;
lz_options->preset_dictionary_size = options->preset_dictionary_size;
return false;
}
@ -476,8 +469,7 @@ lzma_lzma_encoder_reset(lzma_coder *coder, const lzma_options_lzma *options)
coder->pos_mask = (1U << options->pos_bits) - 1;
coder->literal_context_bits = options->literal_context_bits;
coder->literal_pos_mask = (1 << options->literal_pos_bits) - 1;
coder->literal_pos_mask = (1U << options->literal_pos_bits) - 1;
// Range coder
rc_reset(&coder->rc);
@ -519,7 +511,19 @@ lzma_lzma_encoder_reset(lzma_coder *coder, const lzma_options_lzma *options)
length_encoder_reset(&coder->rep_len_encoder,
1U << options->pos_bits, coder->fast_mode);
// FIXME: Too big or too small won't work when resetting in the middle of LZMA2.
// Price counts are incremented every time appropriate probabilities
// are changed. price counts are set to zero when the price tables
// are updated, which is done when the appropriate price counts have
// big enough value, and lzma_mf.read_ahead == 0 which happens at
// least every OPTS (a few thousand) possible price count increments.
//
// By resetting price counts to UINT32_MAX / 2, we make sure that the
// price tables will be initialized before they will be used (since
// the value is definitely big enough), and that it is OK to increment
// price counts without risk of integer overflow (since UINT32_MAX / 2
// is small enough). The current code doesn't increment price counts
// before initializing price tables, but it maybe done in future if
// we add support for saving the state between LZMA2 chunks.
coder->match_price_count = UINT32_MAX / 2;
coder->align_price_count = UINT32_MAX / 2;
@ -540,10 +544,10 @@ lzma_lzma_encoder_create(lzma_coder **coder_ptr, lzma_allocator *allocator,
lzma_coder *coder = *coder_ptr;
// Validate options that aren't validated elsewhere.
if (!is_lclppb_valid(options)
|| options->fast_bytes < LZMA_FAST_BYTES_MIN
|| options->fast_bytes > LZMA_FAST_BYTES_MAX)
// Validate some of the options. LZ encoder validates fast_bytes too
// but we need a valid value here earlier.
if (!is_lclppb_valid(options) || options->fast_bytes < MATCH_LEN_MIN
|| options->fast_bytes > MATCH_LEN_MAX)
return LZMA_OPTIONS_ERROR;
// Set compression mode.
@ -581,9 +585,7 @@ lzma_lzma_encoder_create(lzma_coder **coder_ptr, lzma_allocator *allocator,
lzma_lzma_encoder_reset(coder, options);
// LZ encoder options FIXME validation
if (set_lz_options(lz_options, options))
return LZMA_OPTIONS_ERROR;
set_lz_options(lz_options, options);
return LZMA_OK;
}
@ -603,25 +605,6 @@ extern lzma_ret
lzma_lzma_encoder_init(lzma_next_coder *next, lzma_allocator *allocator,
const lzma_filter_info *filters)
{
// Initialization call chain:
//
// lzma_lzma_encoder_init()
// `-- lzma_lz_encoder_init()
// `-- lzma_encoder_init()
// `-- lzma_encoder_init2()
//
// The above complexity is to let LZ encoder store the pointer to
// the LZMA encoder structure. Encoding call tree:
//
// lz_encode()
// |-- fill_window()
// | `-- Next coder in the chain, if any
// `-- lzma_encode()
// |-- lzma_dict_find()
// `-- lzma_dict_skip()
//
// FIXME ^
//
return lzma_lz_encoder_init(
next, allocator, filters, &lzma_encoder_init);
}
@ -631,8 +614,7 @@ extern uint64_t
lzma_lzma_encoder_memusage(const void *options)
{
lzma_lz_options lz_options;
if (set_lz_options(&lz_options, options))
return UINT64_MAX;
set_lz_options(&lz_options, options);
const uint64_t lz_memusage = lzma_lz_encoder_memusage(&lz_options);
if (lz_memusage == UINT64_MAX)

59
src/liblzma/lzma/lzma_encoder_features.c
View File

@ -1,59 +0,0 @@
///////////////////////////////////////////////////////////////////////////////
//
/// \file lzma_encoder_features.c
/// \brief Information about features enabled at compile time
//
// Copyright (C) 2007 Lasse Collin
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library 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
// Lesser General Public License for more details.
//
///////////////////////////////////////////////////////////////////////////////
#include "common.h"
static lzma_mode modes[] = {
LZMA_MODE_FAST,
LZMA_MODE_NORMAL,
LZMA_MODE_INVALID
};
LZMA_API const lzma_mode *const lzma_available_modes = modes;
static lzma_match_finder match_finders[] = {
#ifdef HAVE_MF_HC3
LZMA_MF_HC3,
#endif
#ifdef HAVE_MF_HC4
LZMA_MF_HC4,
#endif
#ifdef HAVE_MF_BT2
LZMA_MF_BT2,
#endif
#ifdef HAVE_MF_BT3
LZMA_MF_BT3,
#endif
#ifdef HAVE_MF_BT4
LZMA_MF_BT4,
#endif
LZMA_MF_INVALID
};
LZMA_API const lzma_match_finder *const lzma_available_match_finders
= match_finders;