| Index: xz/src/liblzma/common/stream_encoder.c
|
| ===================================================================
|
| --- xz/src/liblzma/common/stream_encoder.c (revision 0)
|
| +++ xz/src/liblzma/common/stream_encoder.c (revision 0)
|
| @@ -0,0 +1,331 @@
|
| +///////////////////////////////////////////////////////////////////////////////
|
| +//
|
| +/// \file stream_encoder.c
|
| +/// \brief Encodes .xz Streams
|
| +//
|
| +// Author: Lasse Collin
|
| +//
|
| +// This file has been put into the public domain.
|
| +// You can do whatever you want with this file.
|
| +//
|
| +///////////////////////////////////////////////////////////////////////////////
|
| +
|
| +#include "stream_encoder.h"
|
| +#include "block_encoder.h"
|
| +#include "index_encoder.h"
|
| +
|
| +
|
| +struct lzma_coder_s {
|
| + enum {
|
| + SEQ_STREAM_HEADER,
|
| + SEQ_BLOCK_INIT,
|
| + SEQ_BLOCK_HEADER,
|
| + SEQ_BLOCK_ENCODE,
|
| + SEQ_INDEX_ENCODE,
|
| + SEQ_STREAM_FOOTER,
|
| + } sequence;
|
| +
|
| + /// True if Block encoder has been initialized by
|
| + /// lzma_stream_encoder_init() or stream_encoder_update()
|
| + /// and thus doesn't need to be initialized in stream_encode().
|
| + bool block_encoder_is_initialized;
|
| +
|
| + /// Block
|
| + lzma_next_coder block_encoder;
|
| +
|
| + /// Options for the Block encoder
|
| + lzma_block block_options;
|
| +
|
| + /// The filter chain currently in use
|
| + lzma_filter filters[LZMA_FILTERS_MAX + 1];
|
| +
|
| + /// Index encoder. This is separate from Block encoder, because this
|
| + /// doesn't take much memory, and when encoding multiple Streams
|
| + /// with the same encoding options we avoid reallocating memory.
|
| + lzma_next_coder index_encoder;
|
| +
|
| + /// Index to hold sizes of the Blocks
|
| + lzma_index *index;
|
| +
|
| + /// Read position in buffer[]
|
| + size_t buffer_pos;
|
| +
|
| + /// Total number of bytes in buffer[]
|
| + size_t buffer_size;
|
| +
|
| + /// Buffer to hold Stream Header, Block Header, and Stream Footer.
|
| + /// Block Header has biggest maximum size.
|
| + uint8_t buffer[LZMA_BLOCK_HEADER_SIZE_MAX];
|
| +};
|
| +
|
| +
|
| +static lzma_ret
|
| +block_encoder_init(lzma_coder *coder, lzma_allocator *allocator)
|
| +{
|
| + // Prepare the Block options. Even though Block encoder doesn't need
|
| + // compressed_size, uncompressed_size, and header_size to be
|
| + // initialized, it is a good idea to do it here, because this way
|
| + // we catch if someone gave us Filter ID that cannot be used in
|
| + // Blocks/Streams.
|
| + coder->block_options.compressed_size = LZMA_VLI_UNKNOWN;
|
| + coder->block_options.uncompressed_size = LZMA_VLI_UNKNOWN;
|
| +
|
| + return_if_error(lzma_block_header_size(&coder->block_options));
|
| +
|
| + // Initialize the actual Block encoder.
|
| + return lzma_block_encoder_init(&coder->block_encoder, allocator,
|
| + &coder->block_options);
|
| +}
|
| +
|
| +
|
| +static lzma_ret
|
| +stream_encode(lzma_coder *coder, lzma_allocator *allocator,
|
| + const uint8_t *restrict in, size_t *restrict in_pos,
|
| + size_t in_size, uint8_t *restrict out,
|
| + size_t *restrict out_pos, size_t out_size, lzma_action action)
|
| +{
|
| + // Main loop
|
| + while (*out_pos < out_size)
|
| + switch (coder->sequence) {
|
| + case SEQ_STREAM_HEADER:
|
| + case SEQ_BLOCK_HEADER:
|
| + case SEQ_STREAM_FOOTER:
|
| + lzma_bufcpy(coder->buffer, &coder->buffer_pos,
|
| + coder->buffer_size, out, out_pos, out_size);
|
| + if (coder->buffer_pos < coder->buffer_size)
|
| + return LZMA_OK;
|
| +
|
| + if (coder->sequence == SEQ_STREAM_FOOTER)
|
| + return LZMA_STREAM_END;
|
| +
|
| + coder->buffer_pos = 0;
|
| + ++coder->sequence;
|
| + break;
|
| +
|
| + case SEQ_BLOCK_INIT: {
|
| + if (*in_pos == in_size) {
|
| + // If we are requested to flush or finish the current
|
| + // Block, return LZMA_STREAM_END immediately since
|
| + // there's nothing to do.
|
| + if (action != LZMA_FINISH)
|
| + return action == LZMA_RUN
|
| + ? LZMA_OK : LZMA_STREAM_END;
|
| +
|
| + // The application had used LZMA_FULL_FLUSH to finish
|
| + // the previous Block, but now wants to finish without
|
| + // encoding new data, or it is simply creating an
|
| + // empty Stream with no Blocks.
|
| + //
|
| + // Initialize the Index encoder, and continue to
|
| + // actually encoding the Index.
|
| + return_if_error(lzma_index_encoder_init(
|
| + &coder->index_encoder, allocator,
|
| + coder->index));
|
| + coder->sequence = SEQ_INDEX_ENCODE;
|
| + break;
|
| + }
|
| +
|
| + // Initialize the Block encoder unless it was already
|
| + // initialized by lzma_stream_encoder_init() or
|
| + // stream_encoder_update().
|
| + if (!coder->block_encoder_is_initialized)
|
| + return_if_error(block_encoder_init(coder, allocator));
|
| +
|
| + // Make it false so that we don't skip the initialization
|
| + // with the next Block.
|
| + coder->block_encoder_is_initialized = false;
|
| +
|
| + // Encode the Block Header. This shouldn't fail since we have
|
| + // already initialized the Block encoder.
|
| + if (lzma_block_header_encode(&coder->block_options,
|
| + coder->buffer) != LZMA_OK)
|
| + return LZMA_PROG_ERROR;
|
| +
|
| + coder->buffer_size = coder->block_options.header_size;
|
| + coder->sequence = SEQ_BLOCK_HEADER;
|
| + break;
|
| + }
|
| +
|
| + case SEQ_BLOCK_ENCODE: {
|
| + static const lzma_action convert[4] = {
|
| + LZMA_RUN,
|
| + LZMA_SYNC_FLUSH,
|
| + LZMA_FINISH,
|
| + LZMA_FINISH,
|
| + };
|
| +
|
| + const lzma_ret ret = coder->block_encoder.code(
|
| + coder->block_encoder.coder, allocator,
|
| + in, in_pos, in_size,
|
| + out, out_pos, out_size, convert[action]);
|
| + if (ret != LZMA_STREAM_END || action == LZMA_SYNC_FLUSH)
|
| + return ret;
|
| +
|
| + // Add a new Index Record.
|
| + const lzma_vli unpadded_size = lzma_block_unpadded_size(
|
| + &coder->block_options);
|
| + assert(unpadded_size != 0);
|
| + return_if_error(lzma_index_append(coder->index, allocator,
|
| + unpadded_size,
|
| + coder->block_options.uncompressed_size));
|
| +
|
| + coder->sequence = SEQ_BLOCK_INIT;
|
| + break;
|
| + }
|
| +
|
| + case SEQ_INDEX_ENCODE: {
|
| + // Call the Index encoder. It doesn't take any input, so
|
| + // those pointers can be NULL.
|
| + const lzma_ret ret = coder->index_encoder.code(
|
| + coder->index_encoder.coder, allocator,
|
| + NULL, NULL, 0,
|
| + out, out_pos, out_size, LZMA_RUN);
|
| + if (ret != LZMA_STREAM_END)
|
| + return ret;
|
| +
|
| + // Encode the Stream Footer into coder->buffer.
|
| + const lzma_stream_flags stream_flags = {
|
| + .version = 0,
|
| + .backward_size = lzma_index_size(coder->index),
|
| + .check = coder->block_options.check,
|
| + };
|
| +
|
| + if (lzma_stream_footer_encode(&stream_flags, coder->buffer)
|
| + != LZMA_OK)
|
| + return LZMA_PROG_ERROR;
|
| +
|
| + coder->buffer_size = LZMA_STREAM_HEADER_SIZE;
|
| + coder->sequence = SEQ_STREAM_FOOTER;
|
| + break;
|
| + }
|
| +
|
| + default:
|
| + assert(0);
|
| + return LZMA_PROG_ERROR;
|
| + }
|
| +
|
| + return LZMA_OK;
|
| +}
|
| +
|
| +
|
| +static void
|
| +stream_encoder_end(lzma_coder *coder, lzma_allocator *allocator)
|
| +{
|
| + lzma_next_end(&coder->block_encoder, allocator);
|
| + lzma_next_end(&coder->index_encoder, allocator);
|
| + lzma_index_end(coder->index, allocator);
|
| +
|
| + for (size_t i = 0; coder->filters[i].id != LZMA_VLI_UNKNOWN; ++i)
|
| + lzma_free(coder->filters[i].options, allocator);
|
| +
|
| + lzma_free(coder, allocator);
|
| + return;
|
| +}
|
| +
|
| +
|
| +static lzma_ret
|
| +stream_encoder_update(lzma_coder *coder, lzma_allocator *allocator,
|
| + const lzma_filter *filters,
|
| + const lzma_filter *reversed_filters)
|
| +{
|
| + if (coder->sequence <= SEQ_BLOCK_INIT) {
|
| + // There is no incomplete Block waiting to be finished,
|
| + // thus we can change the whole filter chain. Start by
|
| + // trying to initialize the Block encoder with the new
|
| + // chain. This way we detect if the chain is valid.
|
| + coder->block_encoder_is_initialized = false;
|
| + coder->block_options.filters = (lzma_filter *)(filters);
|
| + const lzma_ret ret = block_encoder_init(coder, allocator);
|
| + coder->block_options.filters = coder->filters;
|
| + if (ret != LZMA_OK)
|
| + return ret;
|
| +
|
| + coder->block_encoder_is_initialized = true;
|
| +
|
| + } else if (coder->sequence <= SEQ_BLOCK_ENCODE) {
|
| + // We are in the middle of a Block. Try to update only
|
| + // the filter-specific options.
|
| + return_if_error(coder->block_encoder.update(
|
| + coder->block_encoder.coder, allocator,
|
| + filters, reversed_filters));
|
| + } else {
|
| + // Trying to update the filter chain when we are already
|
| + // encoding Index or Stream Footer.
|
| + return LZMA_PROG_ERROR;
|
| + }
|
| +
|
| + // Free the copy of the old chain and make a copy of the new chain.
|
| + for (size_t i = 0; coder->filters[i].id != LZMA_VLI_UNKNOWN; ++i)
|
| + lzma_free(coder->filters[i].options, allocator);
|
| +
|
| + return lzma_filters_copy(filters, coder->filters, allocator);
|
| +}
|
| +
|
| +
|
| +extern lzma_ret
|
| +lzma_stream_encoder_init(lzma_next_coder *next, lzma_allocator *allocator,
|
| + const lzma_filter *filters, lzma_check check)
|
| +{
|
| + lzma_next_coder_init(&lzma_stream_encoder_init, next, allocator);
|
| +
|
| + if (filters == NULL)
|
| + return LZMA_PROG_ERROR;
|
| +
|
| + if (next->coder == NULL) {
|
| + next->coder = lzma_alloc(sizeof(lzma_coder), allocator);
|
| + if (next->coder == NULL)
|
| + return LZMA_MEM_ERROR;
|
| +
|
| + next->code = &stream_encode;
|
| + next->end = &stream_encoder_end;
|
| + next->update = &stream_encoder_update;
|
| +
|
| + next->coder->block_encoder = LZMA_NEXT_CODER_INIT;
|
| + next->coder->index_encoder = LZMA_NEXT_CODER_INIT;
|
| + next->coder->index = NULL;
|
| + }
|
| +
|
| + // Basic initializations
|
| + next->coder->sequence = SEQ_STREAM_HEADER;
|
| + next->coder->block_options.version = 0;
|
| + next->coder->block_options.check = check;
|
| + next->coder->filters[0].id = LZMA_VLI_UNKNOWN;
|
| +
|
| + // Initialize the Index
|
| + lzma_index_end(next->coder->index, allocator);
|
| + next->coder->index = lzma_index_init(allocator);
|
| + if (next->coder->index == NULL)
|
| + return LZMA_MEM_ERROR;
|
| +
|
| + // Encode the Stream Header
|
| + lzma_stream_flags stream_flags = {
|
| + .version = 0,
|
| + .check = check,
|
| + };
|
| + return_if_error(lzma_stream_header_encode(
|
| + &stream_flags, next->coder->buffer));
|
| +
|
| + next->coder->buffer_pos = 0;
|
| + next->coder->buffer_size = LZMA_STREAM_HEADER_SIZE;
|
| +
|
| + // Initialize the Block encoder. This way we detect unsupported
|
| + // filter chains when initializing the Stream encoder instead of
|
| + // giving an error after Stream Header has already written out.
|
| + return stream_encoder_update(
|
| + next->coder, allocator, filters, NULL);
|
| +}
|
| +
|
| +
|
| +extern LZMA_API(lzma_ret)
|
| +lzma_stream_encoder(lzma_stream *strm,
|
| + const lzma_filter *filters, lzma_check check)
|
| +{
|
| + lzma_next_strm_init(lzma_stream_encoder_init, strm, filters, check);
|
| +
|
| + strm->internal->supported_actions[LZMA_RUN] = true;
|
| + strm->internal->supported_actions[LZMA_SYNC_FLUSH] = true;
|
| + strm->internal->supported_actions[LZMA_FULL_FLUSH] = true;
|
| + strm->internal->supported_actions[LZMA_FINISH] = true;
|
| +
|
| + return LZMA_OK;
|
| +}
|
|
|
| Property changes on: xz/src/liblzma/common/stream_encoder.c
|
| ___________________________________________________________________
|
| Added: svn:eol-style
|
| + LF
|
|
|
|
|