From 5d018dc03549c1ee4958364712fb0c94e1bf2741 Mon Sep 17 00:00:00 2001 From: Lasse Collin Date: Sun, 9 Dec 2007 00:42:33 +0200 Subject: Imported to git. --- src/liblzma/common/metadata_encoder.c | 436 ++++++++++++++++++++++++++++++++++ 1 file changed, 436 insertions(+) create mode 100644 src/liblzma/common/metadata_encoder.c (limited to 'src/liblzma/common/metadata_encoder.c') diff --git a/src/liblzma/common/metadata_encoder.c b/src/liblzma/common/metadata_encoder.c new file mode 100644 index 00000000..17587c5c --- /dev/null +++ b/src/liblzma/common/metadata_encoder.c @@ -0,0 +1,436 @@ +/////////////////////////////////////////////////////////////////////////////// +// +/// \file metadata_encoder.c +/// \brief Encodes metadata to be stored into Metadata Blocks +// +// 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 "metadata_encoder.h" +#include "block_encoder.h" + + +struct lzma_coder_s { + enum { + SEQ_FLAGS, + SEQ_HEADER_METADATA_SIZE, + SEQ_TOTAL_SIZE, + SEQ_UNCOMPRESSED_SIZE, + SEQ_INDEX_COUNT, + SEQ_INDEX_TOTAL, + SEQ_INDEX_UNCOMPRESSED, + SEQ_EXTRA_ID, + SEQ_EXTRA_SIZE, + SEQ_EXTRA_DATA, + SEQ_END, + } sequence; + + /// Position in variable-length integers + size_t pos; + + /// Local copy of the Metadata structure. Note that we keep + /// a copy only of the main structure, not Index or Extra Records. + lzma_metadata metadata; + + /// Number of Records in Index + size_t index_count; + + /// Index Record currently being processed + const lzma_index *index_current; + + /// Block encoder for the encoded Metadata + lzma_next_coder block_encoder; + + /// True once everything except compression has been done. + bool end_was_reached; + + /// buffer[buffer_pos] is the first byte that needs to be compressed. + size_t buffer_pos; + + /// buffer[buffer_size] is the next position where a byte will be + /// written by process(). + size_t buffer_size; + + /// Temporary buffer to which encoded Metadata is written before + /// it is compressed. + uint8_t buffer[LZMA_BUFFER_SIZE]; +}; + + +#define write_vli(num) \ +do { \ + const lzma_ret ret = lzma_vli_encode(num, &coder->pos, 1, \ + coder->buffer, &coder->buffer_size, \ + LZMA_BUFFER_SIZE); \ + if (ret != LZMA_STREAM_END) \ + return ret; \ + coder->pos = 0; \ +} while (0) + + +static lzma_ret +process(lzma_coder *coder) +{ + while (coder->buffer_size < LZMA_BUFFER_SIZE) + switch (coder->sequence) { + case SEQ_FLAGS: + coder->buffer[coder->buffer_size] = 0; + + if (coder->metadata.header_metadata_size + != LZMA_VLI_VALUE_UNKNOWN) + coder->buffer[coder->buffer_size] |= 0x01; + + if (coder->metadata.total_size != LZMA_VLI_VALUE_UNKNOWN) + coder->buffer[coder->buffer_size] |= 0x02; + + if (coder->metadata.uncompressed_size + != LZMA_VLI_VALUE_UNKNOWN) + coder->buffer[coder->buffer_size] |= 0x04; + + if (coder->index_count > 0) + coder->buffer[coder->buffer_size] |= 0x08; + + if (coder->metadata.extra != NULL) + coder->buffer[coder->buffer_size] |= 0x80; + + ++coder->buffer_size; + coder->sequence = SEQ_HEADER_METADATA_SIZE; + break; + + case SEQ_HEADER_METADATA_SIZE: + if (coder->metadata.header_metadata_size + != LZMA_VLI_VALUE_UNKNOWN) + write_vli(coder->metadata.header_metadata_size); + + coder->sequence = SEQ_TOTAL_SIZE; + break; + + case SEQ_TOTAL_SIZE: + if (coder->metadata.total_size != LZMA_VLI_VALUE_UNKNOWN) + write_vli(coder->metadata.total_size); + + coder->sequence = SEQ_UNCOMPRESSED_SIZE; + break; + + case SEQ_UNCOMPRESSED_SIZE: + if (coder->metadata.uncompressed_size + != LZMA_VLI_VALUE_UNKNOWN) + write_vli(coder->metadata.uncompressed_size); + + coder->sequence = SEQ_INDEX_COUNT; + break; + + case SEQ_INDEX_COUNT: + if (coder->index_count == 0) { + if (coder->metadata.extra == NULL) { + coder->sequence = SEQ_END; + return LZMA_STREAM_END; + } + + coder->sequence = SEQ_EXTRA_ID; + break; + } + + write_vli(coder->index_count); + coder->sequence = SEQ_INDEX_TOTAL; + break; + + case SEQ_INDEX_TOTAL: + write_vli(coder->index_current->total_size); + + coder->index_current = coder->index_current->next; + if (coder->index_current == NULL) { + coder->index_current = coder->metadata.index; + coder->sequence = SEQ_INDEX_UNCOMPRESSED; + } + + break; + + case SEQ_INDEX_UNCOMPRESSED: + write_vli(coder->index_current->uncompressed_size); + + coder->index_current = coder->index_current->next; + if (coder->index_current != NULL) + break; + + if (coder->metadata.extra != NULL) { + coder->sequence = SEQ_EXTRA_ID; + break; + } + + coder->sequence = SEQ_END; + return LZMA_STREAM_END; + + case SEQ_EXTRA_ID: { + const lzma_ret ret = lzma_vli_encode( + coder->metadata.extra->id, &coder->pos, 1, + coder->buffer, &coder->buffer_size, + LZMA_BUFFER_SIZE); + switch (ret) { + case LZMA_OK: + break; + + case LZMA_STREAM_END: + coder->pos = 0; + + // Handle the special ID 0. + if (coder->metadata.extra->id == 0) { + coder->metadata.extra + = coder->metadata.extra->next; + if (coder->metadata.extra == NULL) { + coder->sequence = SEQ_END; + return LZMA_STREAM_END; + } + + coder->sequence = SEQ_EXTRA_ID; + + } else { + coder->sequence = SEQ_EXTRA_SIZE; + } + + break; + + default: + return ret; + } + + break; + } + + case SEQ_EXTRA_SIZE: + if (coder->metadata.extra->size >= (lzma_vli)(SIZE_MAX)) + return LZMA_HEADER_ERROR; + + write_vli(coder->metadata.extra->size); + coder->sequence = SEQ_EXTRA_DATA; + break; + + case SEQ_EXTRA_DATA: + bufcpy(coder->metadata.extra->data, &coder->pos, + coder->metadata.extra->size, + coder->buffer, &coder->buffer_size, + LZMA_BUFFER_SIZE); + + if ((size_t)(coder->metadata.extra->size) == coder->pos) { + coder->metadata.extra = coder->metadata.extra->next; + if (coder->metadata.extra == NULL) { + coder->sequence = SEQ_END; + return LZMA_STREAM_END; + } + + coder->pos = 0; + coder->sequence = SEQ_EXTRA_ID; + } + + break; + + case SEQ_END: + // Everything is encoded. Let the compression code finish + // its work now. + return LZMA_STREAM_END; + } + + return LZMA_OK; +} + + +static lzma_ret +metadata_encode(lzma_coder *coder, lzma_allocator *allocator, + const uint8_t *restrict in lzma_attribute((unused)), + size_t *restrict in_pos lzma_attribute((unused)), + size_t in_size lzma_attribute((unused)), uint8_t *restrict out, + size_t *restrict out_pos, size_t out_size, + lzma_action action lzma_attribute((unused))) +{ + while (!coder->end_was_reached) { + // Flush coder->buffer if it isn't empty. + if (coder->buffer_size > 0) { + const lzma_ret ret = coder->block_encoder.code( + coder->block_encoder.coder, allocator, + coder->buffer, &coder->buffer_pos, + coder->buffer_size, + out, out_pos, out_size, LZMA_RUN); + if (coder->buffer_pos < coder->buffer_size + || ret != LZMA_OK) + return ret; + + coder->buffer_pos = 0; + coder->buffer_size = 0; + } + + const lzma_ret ret = process(coder); + + switch (ret) { + case LZMA_OK: + break; + + case LZMA_STREAM_END: + coder->end_was_reached = true; + break; + + default: + return ret; + } + } + + // Finish + return coder->block_encoder.code(coder->block_encoder.coder, allocator, + coder->buffer, &coder->buffer_pos, coder->buffer_size, + out, out_pos, out_size, LZMA_FINISH); +} + + +static void +metadata_encoder_end(lzma_coder *coder, lzma_allocator *allocator) +{ + lzma_next_coder_end(&coder->block_encoder, allocator); + lzma_free(coder, allocator); + return; +} + + +static lzma_ret +metadata_encoder_init(lzma_next_coder *next, lzma_allocator *allocator, + lzma_options_block *options, const lzma_metadata *metadata) +{ + if (options == NULL || metadata == 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 = &metadata_encode; + next->end = &metadata_encoder_end; + next->coder->block_encoder = LZMA_NEXT_CODER_INIT; + } + + next->coder->sequence = SEQ_FLAGS; + next->coder->pos = 0; + next->coder->metadata = *metadata; + next->coder->index_count = 0; + next->coder->index_current = metadata->index; + next->coder->end_was_reached = false; + next->coder->buffer_pos = 0; + next->coder->buffer_size = 0; + + // Count and validate the Index Records. + { + const lzma_index *i = metadata->index; + while (i != NULL) { + if (i->total_size > LZMA_VLI_VALUE_MAX + || i->uncompressed_size + > LZMA_VLI_VALUE_MAX) + return LZMA_PROG_ERROR; + + ++next->coder->index_count; + i = i->next; + } + } + + // Initialize the Block encoder. + return lzma_block_encoder_init( + &next->coder->block_encoder, allocator, options); +} + + +extern lzma_ret +lzma_metadata_encoder_init(lzma_next_coder *next, lzma_allocator *allocator, + lzma_options_block *options, const lzma_metadata *metadata) +{ + lzma_next_coder_init(metadata_encoder_init, next, allocator, + options, metadata); +} + + +extern LZMA_API lzma_ret +lzma_metadata_encoder(lzma_stream *strm, lzma_options_block *options, + const lzma_metadata *metadata) +{ + lzma_next_strm_init(strm, metadata_encoder_init, options, metadata); + + strm->internal->supported_actions[LZMA_FINISH] = true; + + return LZMA_OK; +} + + +extern LZMA_API lzma_vli +lzma_metadata_size(const lzma_metadata *metadata) +{ + lzma_vli size = 1; // Metadata Flags + + // Validate header_metadata_size, total_size, and uncompressed_size. + if (!lzma_vli_is_valid(metadata->header_metadata_size) + || !lzma_vli_is_valid(metadata->total_size) + || !lzma_vli_is_valid(metadata->uncompressed_size)) + return 0; + + // Add the sizes of these three fields. + if (metadata->header_metadata_size != LZMA_VLI_VALUE_UNKNOWN) + size += lzma_vli_size(metadata->header_metadata_size); + + if (metadata->total_size != LZMA_VLI_VALUE_UNKNOWN) + size += lzma_vli_size(metadata->total_size); + + if (metadata->uncompressed_size != LZMA_VLI_VALUE_UNKNOWN) + size += lzma_vli_size(metadata->uncompressed_size); + + // Index + if (metadata->index != NULL) { + const lzma_index *i = metadata->index; + size_t count = 1; + + do { + const size_t x = lzma_vli_size(i->total_size); + const size_t y = lzma_vli_size(i->uncompressed_size); + if (x == 0 || y == 0) + return 0; + + size += x + y; + ++count; + i = i->next; + + } while (i != NULL); + + const size_t tmp = lzma_vli_size(count); + if (tmp == 0) + return 0; + + size += tmp; + } + + // Extra + { + const lzma_extra *e = metadata->extra; + while (e != NULL) { + // Validate the numbers. + if (e->id > LZMA_VLI_VALUE_MAX + || e->size >= (lzma_vli)(SIZE_MAX)) + return 0; + + // Add the sizes. + size += lzma_vli_size(e->id); + if (e->id != 0) { + size += lzma_vli_size(e->size); + size += e->size; + } + + e = e->next; + } + } + + return size; +} -- cgit v1.2.3