| Index: xz/src/liblzma/lzma/lzma2_encoder.c
|
| ===================================================================
|
| --- xz/src/liblzma/lzma/lzma2_encoder.c (revision 0)
|
| +++ xz/src/liblzma/lzma/lzma2_encoder.c (revision 0)
|
| @@ -0,0 +1,393 @@
|
| +///////////////////////////////////////////////////////////////////////////////
|
| +//
|
| +/// \file lzma2_encoder.c
|
| +/// \brief LZMA2 encoder
|
| +///
|
| +// Authors: Igor Pavlov
|
| +// Lasse Collin
|
| +//
|
| +// This file has been put into the public domain.
|
| +// You can do whatever you want with this file.
|
| +//
|
| +///////////////////////////////////////////////////////////////////////////////
|
| +
|
| +#include "lz_encoder.h"
|
| +#include "lzma_encoder.h"
|
| +#include "fastpos.h"
|
| +#include "lzma2_encoder.h"
|
| +
|
| +
|
| +struct lzma_coder_s {
|
| + enum {
|
| + SEQ_INIT,
|
| + SEQ_LZMA_ENCODE,
|
| + SEQ_LZMA_COPY,
|
| + SEQ_UNCOMPRESSED_HEADER,
|
| + SEQ_UNCOMPRESSED_COPY,
|
| + } sequence;
|
| +
|
| + /// LZMA encoder
|
| + lzma_coder *lzma;
|
| +
|
| + /// LZMA options currently in use.
|
| + lzma_options_lzma opt_cur;
|
| +
|
| + bool need_properties;
|
| + bool need_state_reset;
|
| + bool need_dictionary_reset;
|
| +
|
| + /// Uncompressed size of a chunk
|
| + size_t uncompressed_size;
|
| +
|
| + /// Compressed size of a chunk (excluding headers); this is also used
|
| + /// to indicate the end of buf[] in SEQ_LZMA_COPY.
|
| + size_t compressed_size;
|
| +
|
| + /// Read position in buf[]
|
| + size_t buf_pos;
|
| +
|
| + /// Buffer to hold the chunk header and LZMA compressed data
|
| + uint8_t buf[LZMA2_HEADER_MAX + LZMA2_CHUNK_MAX];
|
| +};
|
| +
|
| +
|
| +static void
|
| +lzma2_header_lzma(lzma_coder *coder)
|
| +{
|
| + assert(coder->uncompressed_size > 0);
|
| + assert(coder->uncompressed_size <= LZMA2_UNCOMPRESSED_MAX);
|
| + assert(coder->compressed_size > 0);
|
| + assert(coder->compressed_size <= LZMA2_CHUNK_MAX);
|
| +
|
| + size_t pos;
|
| +
|
| + if (coder->need_properties) {
|
| + pos = 0;
|
| +
|
| + if (coder->need_dictionary_reset)
|
| + coder->buf[pos] = 0x80 + (3 << 5);
|
| + else
|
| + coder->buf[pos] = 0x80 + (2 << 5);
|
| + } else {
|
| + pos = 1;
|
| +
|
| + if (coder->need_state_reset)
|
| + coder->buf[pos] = 0x80 + (1 << 5);
|
| + else
|
| + coder->buf[pos] = 0x80;
|
| + }
|
| +
|
| + // Set the start position for copying.
|
| + coder->buf_pos = pos;
|
| +
|
| + // Uncompressed size
|
| + size_t size = coder->uncompressed_size - 1;
|
| + coder->buf[pos++] += size >> 16;
|
| + coder->buf[pos++] = (size >> 8) & 0xFF;
|
| + coder->buf[pos++] = size & 0xFF;
|
| +
|
| + // Compressed size
|
| + size = coder->compressed_size - 1;
|
| + coder->buf[pos++] = size >> 8;
|
| + coder->buf[pos++] = size & 0xFF;
|
| +
|
| + // Properties, if needed
|
| + if (coder->need_properties)
|
| + lzma_lzma_lclppb_encode(&coder->opt_cur, coder->buf + pos);
|
| +
|
| + coder->need_properties = false;
|
| + coder->need_state_reset = false;
|
| + coder->need_dictionary_reset = false;
|
| +
|
| + // The copying code uses coder->compressed_size to indicate the end
|
| + // of coder->buf[], so we need add the maximum size of the header here.
|
| + coder->compressed_size += LZMA2_HEADER_MAX;
|
| +
|
| + return;
|
| +}
|
| +
|
| +
|
| +static void
|
| +lzma2_header_uncompressed(lzma_coder *coder)
|
| +{
|
| + assert(coder->uncompressed_size > 0);
|
| + assert(coder->uncompressed_size <= LZMA2_CHUNK_MAX);
|
| +
|
| + // If this is the first chunk, we need to include dictionary
|
| + // reset indicator.
|
| + if (coder->need_dictionary_reset)
|
| + coder->buf[0] = 1;
|
| + else
|
| + coder->buf[0] = 2;
|
| +
|
| + coder->need_dictionary_reset = false;
|
| +
|
| + // "Compressed" size
|
| + coder->buf[1] = (coder->uncompressed_size - 1) >> 8;
|
| + coder->buf[2] = (coder->uncompressed_size - 1) & 0xFF;
|
| +
|
| + // Set the start position for copying.
|
| + coder->buf_pos = 0;
|
| + return;
|
| +}
|
| +
|
| +
|
| +static lzma_ret
|
| +lzma2_encode(lzma_coder *restrict coder, lzma_mf *restrict mf,
|
| + uint8_t *restrict out, size_t *restrict out_pos,
|
| + size_t out_size)
|
| +{
|
| + while (*out_pos < out_size)
|
| + switch (coder->sequence) {
|
| + case SEQ_INIT:
|
| + // If there's no input left and we are flushing or finishing,
|
| + // don't start a new chunk.
|
| + if (mf_unencoded(mf) == 0) {
|
| + // Write end of payload marker if finishing.
|
| + if (mf->action == LZMA_FINISH)
|
| + out[(*out_pos)++] = 0;
|
| +
|
| + return mf->action == LZMA_RUN
|
| + ? LZMA_OK : LZMA_STREAM_END;
|
| + }
|
| +
|
| + if (coder->need_state_reset)
|
| + return_if_error(lzma_lzma_encoder_reset(
|
| + coder->lzma, &coder->opt_cur));
|
| +
|
| + coder->uncompressed_size = 0;
|
| + coder->compressed_size = 0;
|
| + coder->sequence = SEQ_LZMA_ENCODE;
|
| +
|
| + // Fall through
|
| +
|
| + case SEQ_LZMA_ENCODE: {
|
| + // Calculate how much more uncompressed data this chunk
|
| + // could accept.
|
| + const uint32_t left = LZMA2_UNCOMPRESSED_MAX
|
| + - coder->uncompressed_size;
|
| + uint32_t limit;
|
| +
|
| + if (left < mf->match_len_max) {
|
| + // Must flush immediately since the next LZMA symbol
|
| + // could make the uncompressed size of the chunk too
|
| + // big.
|
| + limit = 0;
|
| + } else {
|
| + // Calculate maximum read_limit that is OK from point
|
| + // of view of LZMA2 chunk size.
|
| + limit = mf->read_pos - mf->read_ahead
|
| + + left - mf->match_len_max;
|
| + }
|
| +
|
| + // Save the start position so that we can update
|
| + // coder->uncompressed_size.
|
| + const uint32_t read_start = mf->read_pos - mf->read_ahead;
|
| +
|
| + // Call the LZMA encoder until the chunk is finished.
|
| + const lzma_ret ret = lzma_lzma_encode(coder->lzma, mf,
|
| + coder->buf + LZMA2_HEADER_MAX,
|
| + &coder->compressed_size,
|
| + LZMA2_CHUNK_MAX, limit);
|
| +
|
| + coder->uncompressed_size += mf->read_pos - mf->read_ahead
|
| + - read_start;
|
| +
|
| + assert(coder->compressed_size <= LZMA2_CHUNK_MAX);
|
| + assert(coder->uncompressed_size <= LZMA2_UNCOMPRESSED_MAX);
|
| +
|
| + if (ret != LZMA_STREAM_END)
|
| + return LZMA_OK;
|
| +
|
| + // See if the chunk compressed. If it didn't, we encode it
|
| + // as uncompressed chunk. This saves a few bytes of space
|
| + // and makes decoding faster.
|
| + if (coder->compressed_size >= coder->uncompressed_size) {
|
| + coder->uncompressed_size += mf->read_ahead;
|
| + assert(coder->uncompressed_size
|
| + <= LZMA2_UNCOMPRESSED_MAX);
|
| + mf->read_ahead = 0;
|
| + lzma2_header_uncompressed(coder);
|
| + coder->need_state_reset = true;
|
| + coder->sequence = SEQ_UNCOMPRESSED_HEADER;
|
| + break;
|
| + }
|
| +
|
| + // The chunk did compress at least by one byte, so we store
|
| + // the chunk as LZMA.
|
| + lzma2_header_lzma(coder);
|
| +
|
| + coder->sequence = SEQ_LZMA_COPY;
|
| + }
|
| +
|
| + // Fall through
|
| +
|
| + case SEQ_LZMA_COPY:
|
| + // Copy the compressed chunk along its headers to the
|
| + // output buffer.
|
| + lzma_bufcpy(coder->buf, &coder->buf_pos,
|
| + coder->compressed_size,
|
| + out, out_pos, out_size);
|
| + if (coder->buf_pos != coder->compressed_size)
|
| + return LZMA_OK;
|
| +
|
| + coder->sequence = SEQ_INIT;
|
| + break;
|
| +
|
| + case SEQ_UNCOMPRESSED_HEADER:
|
| + // Copy the three-byte header to indicate uncompressed chunk.
|
| + lzma_bufcpy(coder->buf, &coder->buf_pos,
|
| + LZMA2_HEADER_UNCOMPRESSED,
|
| + out, out_pos, out_size);
|
| + if (coder->buf_pos != LZMA2_HEADER_UNCOMPRESSED)
|
| + return LZMA_OK;
|
| +
|
| + coder->sequence = SEQ_UNCOMPRESSED_COPY;
|
| +
|
| + // Fall through
|
| +
|
| + case SEQ_UNCOMPRESSED_COPY:
|
| + // Copy the uncompressed data as is from the dictionary
|
| + // to the output buffer.
|
| + mf_read(mf, out, out_pos, out_size, &coder->uncompressed_size);
|
| + if (coder->uncompressed_size != 0)
|
| + return LZMA_OK;
|
| +
|
| + coder->sequence = SEQ_INIT;
|
| + break;
|
| + }
|
| +
|
| + return LZMA_OK;
|
| +}
|
| +
|
| +
|
| +static void
|
| +lzma2_encoder_end(lzma_coder *coder, lzma_allocator *allocator)
|
| +{
|
| + lzma_free(coder->lzma, allocator);
|
| + lzma_free(coder, allocator);
|
| + return;
|
| +}
|
| +
|
| +
|
| +static lzma_ret
|
| +lzma2_encoder_options_update(lzma_coder *coder, const lzma_filter *filter)
|
| +{
|
| + // New options can be set only when there is no incomplete chunk.
|
| + // This is the case at the beginning of the raw stream and right
|
| + // after LZMA_SYNC_FLUSH.
|
| + if (filter->options == NULL || coder->sequence != SEQ_INIT)
|
| + return LZMA_PROG_ERROR;
|
| +
|
| + // Look if there are new options. At least for now,
|
| + // only lc/lp/pb can be changed.
|
| + const lzma_options_lzma *opt = filter->options;
|
| + if (coder->opt_cur.lc != opt->lc || coder->opt_cur.lp != opt->lp
|
| + || coder->opt_cur.pb != opt->pb) {
|
| + // Validate the options.
|
| + if (opt->lc > LZMA_LCLP_MAX || opt->lp > LZMA_LCLP_MAX
|
| + || opt->lc + opt->lp > LZMA_LCLP_MAX
|
| + || opt->pb > LZMA_PB_MAX)
|
| + return LZMA_OPTIONS_ERROR;
|
| +
|
| + // The new options will be used when the encoder starts
|
| + // a new LZMA2 chunk.
|
| + coder->opt_cur.lc = opt->lc;
|
| + coder->opt_cur.lp = opt->lp;
|
| + coder->opt_cur.pb = opt->pb;
|
| + coder->need_properties = true;
|
| + coder->need_state_reset = true;
|
| + }
|
| +
|
| + return LZMA_OK;
|
| +}
|
| +
|
| +
|
| +static lzma_ret
|
| +lzma2_encoder_init(lzma_lz_encoder *lz, lzma_allocator *allocator,
|
| + const void *options, lzma_lz_options *lz_options)
|
| +{
|
| + if (options == NULL)
|
| + return LZMA_PROG_ERROR;
|
| +
|
| + if (lz->coder == NULL) {
|
| + lz->coder = lzma_alloc(sizeof(lzma_coder), allocator);
|
| + if (lz->coder == NULL)
|
| + return LZMA_MEM_ERROR;
|
| +
|
| + lz->code = &lzma2_encode;
|
| + lz->end = &lzma2_encoder_end;
|
| + lz->options_update = &lzma2_encoder_options_update;
|
| +
|
| + lz->coder->lzma = NULL;
|
| + }
|
| +
|
| + lz->coder->opt_cur = *(const lzma_options_lzma *)(options);
|
| +
|
| + lz->coder->sequence = SEQ_INIT;
|
| + lz->coder->need_properties = true;
|
| + lz->coder->need_state_reset = false;
|
| + lz->coder->need_dictionary_reset
|
| + = lz->coder->opt_cur.preset_dict == NULL
|
| + || lz->coder->opt_cur.preset_dict_size == 0;
|
| +
|
| + // Initialize LZMA encoder
|
| + return_if_error(lzma_lzma_encoder_create(&lz->coder->lzma, allocator,
|
| + &lz->coder->opt_cur, lz_options));
|
| +
|
| + // Make sure that we will always have enough history available in
|
| + // case we need to use uncompressed chunks. They are used when the
|
| + // compressed size of a chunk is not smaller than the uncompressed
|
| + // size, so we need to have at least LZMA2_COMPRESSED_MAX bytes
|
| + // history available.
|
| + if (lz_options->before_size + lz_options->dict_size < LZMA2_CHUNK_MAX)
|
| + lz_options->before_size
|
| + = LZMA2_CHUNK_MAX - lz_options->dict_size;
|
| +
|
| + return LZMA_OK;
|
| +}
|
| +
|
| +
|
| +extern lzma_ret
|
| +lzma_lzma2_encoder_init(lzma_next_coder *next, lzma_allocator *allocator,
|
| + const lzma_filter_info *filters)
|
| +{
|
| + return lzma_lz_encoder_init(
|
| + next, allocator, filters, &lzma2_encoder_init);
|
| +}
|
| +
|
| +
|
| +extern uint64_t
|
| +lzma_lzma2_encoder_memusage(const void *options)
|
| +{
|
| + const uint64_t lzma_mem = lzma_lzma_encoder_memusage(options);
|
| + if (lzma_mem == UINT64_MAX)
|
| + return UINT64_MAX;
|
| +
|
| + return sizeof(lzma_coder) + lzma_mem;
|
| +}
|
| +
|
| +
|
| +extern lzma_ret
|
| +lzma_lzma2_props_encode(const void *options, uint8_t *out)
|
| +{
|
| + const lzma_options_lzma *const opt = options;
|
| + uint32_t d = my_max(opt->dict_size, LZMA_DICT_SIZE_MIN);
|
| +
|
| + // Round up to to the next 2^n - 1 or 2^n + 2^(n - 1) - 1 depending
|
| + // on which one is the next:
|
| + --d;
|
| + d |= d >> 2;
|
| + d |= d >> 3;
|
| + d |= d >> 4;
|
| + d |= d >> 8;
|
| + d |= d >> 16;
|
| +
|
| + // Get the highest two bits using the proper encoding:
|
| + if (d == UINT32_MAX)
|
| + out[0] = 40;
|
| + else
|
| + out[0] = get_pos_slot(d + 1) - 24;
|
| +
|
| + return LZMA_OK;
|
| +}
|
|
|
| Property changes on: xz/src/liblzma/lzma/lzma2_encoder.c
|
| ___________________________________________________________________
|
| Added: svn:eol-style
|
| + LF
|
|
|
|
|