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author | Lasse Collin <lasse.collin@tukaani.org> | 2007-12-09 00:42:33 +0200 |
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committer | Lasse Collin <lasse.collin@tukaani.org> | 2007-12-09 00:42:33 +0200 |
commit | 5d018dc03549c1ee4958364712fb0c94e1bf2741 (patch) | |
tree | 1b211911fb33fddb3f04b77f99e81df23623ffc4 /src/liblzma/common/block_encoder.c | |
download | xz-5d018dc03549c1ee4958364712fb0c94e1bf2741.tar.xz |
Imported to git.
Diffstat (limited to 'src/liblzma/common/block_encoder.c')
-rw-r--r-- | src/liblzma/common/block_encoder.c | 375 |
1 files changed, 375 insertions, 0 deletions
diff --git a/src/liblzma/common/block_encoder.c b/src/liblzma/common/block_encoder.c new file mode 100644 index 00000000..77ff78ea --- /dev/null +++ b/src/liblzma/common/block_encoder.c @@ -0,0 +1,375 @@ +/////////////////////////////////////////////////////////////////////////////// +// +/// \file block_encoder.c +/// \brief Encodes .lzma 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 "block_encoder.h" +#include "block_private.h" +#include "raw_encoder.h" +#include "check.h" + + +struct lzma_coder_s { + /// The filters in the chain; initialized with lzma_raw_decoder_init(). + lzma_next_coder next; + + /// Encoding options; we also write Total Size, Compressed Size, and + /// Uncompressed Size back to this structure when the encoding has + /// been finished. + lzma_options_block *options; + + enum { + SEQ_CODE, + SEQ_CHECK_FINISH, + SEQ_CHECK_COPY, + SEQ_UNCOMPRESSED_SIZE, + SEQ_BACKWARD_SIZE, + SEQ_PADDING, + } sequence; + + /// Position in .header and .check. + size_t pos; + + /// Check of the uncompressed data + lzma_check check; + + /// Total Size calculated while encoding + lzma_vli total_size; + + /// Compressed Size calculated while encoding + lzma_vli compressed_size; + + /// Uncompressed Size calculated while encoding + lzma_vli uncompressed_size; + + /// Maximum allowed total_size + lzma_vli total_limit; + + /// Maximum allowed uncompressed_size + lzma_vli uncompressed_limit; + + /// Backward Size - This is a copy of total_size right before + /// the Backward Size field. + lzma_vli backward_size; +}; + + +static lzma_ret +block_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) +{ + // Check that our amount of input stays in proper limits. + if (coder->options->uncompressed_size != LZMA_VLI_VALUE_UNKNOWN) { + if (action == LZMA_FINISH) { + if (coder->options->uncompressed_size + - coder->uncompressed_size + != (lzma_vli)(in_size - *in_pos)) + return LZMA_DATA_ERROR; + } else { + if (coder->options->uncompressed_size + - coder->uncompressed_size + < (lzma_vli)(in_size - *in_pos)) + return LZMA_DATA_ERROR; + } + } else if (LZMA_VLI_VALUE_MAX - coder->uncompressed_size + < (lzma_vli)(in_size - *in_pos)) { + return LZMA_DATA_ERROR; + } + + // Main loop + while (*out_pos < out_size + && (*in_pos < in_size || action == LZMA_FINISH)) + switch (coder->sequence) { + case SEQ_CODE: { + const size_t in_start = *in_pos; + const size_t out_start = *out_pos; + + const lzma_ret ret = coder->next.code(coder->next.coder, + allocator, in, in_pos, in_size, + out, out_pos, out_size, action); + + const size_t in_used = *in_pos - in_start; + const size_t out_used = *out_pos - out_start; + + if (update_size(&coder->total_size, out_used, + coder->total_limit) + || update_size(&coder->compressed_size, + out_used, + coder->options->compressed_size)) + return LZMA_DATA_ERROR; + + // No need to check for overflow because we have already + // checked it at the beginning of this function. + coder->uncompressed_size += in_used; + + lzma_check_update(&coder->check, coder->options->check, + in + in_start, in_used); + + if (ret != LZMA_STREAM_END) + return ret; + + assert(*in_pos == in_size); + + // Compressed and Uncompressed Sizes are now at their final + // values. Verify that they match the values give to us. + if (!is_size_valid(coder->compressed_size, + coder->options->compressed_size) + || !is_size_valid(coder->uncompressed_size, + coder->options->uncompressed_size)) + return LZMA_DATA_ERROR; + + coder->sequence = SEQ_CHECK_FINISH; + break; + } + + case SEQ_CHECK_FINISH: + if (coder->options->check == LZMA_CHECK_NONE) { + coder->sequence = SEQ_UNCOMPRESSED_SIZE; + break; + } + + lzma_check_finish(&coder->check, coder->options->check); + coder->sequence = SEQ_CHECK_COPY; + + // Fall through + + case SEQ_CHECK_COPY: + assert(lzma_check_sizes[coder->options->check] > 0); + + switch (coder->options->check) { + case LZMA_CHECK_CRC32: + out[*out_pos] = coder->check.crc32 >> (coder->pos * 8); + break; + + case LZMA_CHECK_CRC64: + out[*out_pos] = coder->check.crc64 >> (coder->pos * 8); + break; + + case LZMA_CHECK_SHA256: + out[*out_pos] = coder->check.sha256.buffer[coder->pos]; + break; + + default: + assert(0); + return LZMA_PROG_ERROR; + } + + ++*out_pos; + + if (update_size(&coder->total_size, 1, coder->total_limit)) + return LZMA_DATA_ERROR; + + if (++coder->pos == lzma_check_sizes[coder->options->check]) { + coder->pos = 0; + coder->sequence = SEQ_UNCOMPRESSED_SIZE; + } + + break; + + case SEQ_UNCOMPRESSED_SIZE: + if (coder->options->has_uncompressed_size_in_footer) { + const size_t out_start = *out_pos; + + const lzma_ret ret = lzma_vli_encode( + coder->uncompressed_size, + &coder->pos, 1, + out, out_pos, out_size); + + // Updating the size this way instead of doing in a + // single chunk using lzma_vli_size(), because this + // way we detect when exactly we are going out of + // our limits. + if (update_size(&coder->total_size, + *out_pos - out_start, + coder->total_limit)) + return LZMA_DATA_ERROR; + + if (ret != LZMA_STREAM_END) + return ret; + + coder->pos = 0; + } + + coder->backward_size = coder->total_size; + coder->sequence = SEQ_BACKWARD_SIZE; + break; + + case SEQ_BACKWARD_SIZE: + if (coder->options->has_backward_size) { + const size_t out_start = *out_pos; + + const lzma_ret ret = lzma_vli_encode( + coder->backward_size, &coder->pos, 1, + out, out_pos, out_size); + + if (update_size(&coder->total_size, + *out_pos - out_start, + coder->total_limit)) + return LZMA_DATA_ERROR; + + if (ret != LZMA_STREAM_END) + return ret; + } + + coder->sequence = SEQ_PADDING; + break; + + case SEQ_PADDING: + if (coder->options->handle_padding) { + assert(!coder->options + ->has_uncompressed_size_in_footer); + assert(!coder->options->has_backward_size); + assert(coder->options->total_size != LZMA_VLI_VALUE_UNKNOWN); + + if (coder->total_size < coder->options->total_size) { + out[*out_pos] = 0x00; + ++*out_pos; + + if (update_size(&coder->total_size, 1, + coder->total_limit)) + return LZMA_DATA_ERROR; + + break; + } + } + + // Now also Total Size is known. Verify it. + if (!is_size_valid(coder->total_size, + coder->options->total_size)) + return LZMA_DATA_ERROR; + + // Copy the values into coder->options. The caller + // may use this information to construct Index. + coder->options->total_size = coder->total_size; + coder->options->compressed_size = coder->compressed_size; + coder->options->uncompressed_size = coder->uncompressed_size; + + return LZMA_STREAM_END; + + default: + return LZMA_PROG_ERROR; + } + + return LZMA_OK; +} + + +static void +block_encoder_end(lzma_coder *coder, lzma_allocator *allocator) +{ + lzma_next_coder_end(&coder->next, allocator); + lzma_free(coder, allocator); + return; +} + + +static lzma_ret +block_encoder_init(lzma_next_coder *next, lzma_allocator *allocator, + lzma_options_block *options) +{ + // Validate some options. + if (options == NULL + || !lzma_vli_is_valid(options->total_size) + || !lzma_vli_is_valid(options->compressed_size) + || !lzma_vli_is_valid(options->uncompressed_size) + || !lzma_vli_is_valid(options->total_size) + || !lzma_vli_is_valid(options->total_limit) + || !lzma_vli_is_valid(options->uncompressed_limit) + || (options->uncompressed_size + != LZMA_VLI_VALUE_UNKNOWN + && options->uncompressed_size + > options->uncompressed_limit) + || (options->total_size != LZMA_VLI_VALUE_UNKNOWN + && options->total_size + > options->total_limit) + || (!options->has_eopm && options->uncompressed_size + == LZMA_VLI_VALUE_UNKNOWN) + || (options->handle_padding && (options->total_size + == LZMA_VLI_VALUE_UNKNOWN + || options->has_uncompressed_size_in_footer + || options->has_backward_size)) + || options->header_size > options->total_size) + return LZMA_PROG_ERROR; + + // Allocate and initialize *next->coder if needed. + if (next->coder == NULL) { + next->coder = lzma_alloc(sizeof(lzma_coder), allocator); + if (next->coder == NULL) + return LZMA_MEM_ERROR; + + next->code = &block_encode; + next->end = &block_encoder_end; + next->coder->next = LZMA_NEXT_CODER_INIT; + } + + // Initialize the check. + return_if_error(lzma_check_init(&next->coder->check, options->check)); + + // If End of Payload Marker is not used and Uncompressed Size is zero, + // Compressed Data is empty. That is, we don't call the encoder at all. + // We initialize it though; it allows detecting invalid options. + if (!options->has_eopm && options->uncompressed_size == 0) { + // Also Compressed Size must also be zero if it has been + // given to us. + if (!is_size_valid(options->compressed_size, 0)) + return LZMA_PROG_ERROR; + + next->coder->sequence = SEQ_CHECK_FINISH; + } else { + next->coder->sequence = SEQ_CODE; + } + + // Other initializations + next->coder->options = options; + next->coder->pos = 0; + next->coder->total_size = options->header_size; + next->coder->compressed_size = 0; + next->coder->uncompressed_size = 0; + next->coder->total_limit + = MIN(options->total_size, options->total_limit); + next->coder->uncompressed_limit = MIN(options->uncompressed_size, + options->uncompressed_limit); + + // Initialize the requested filters. + return lzma_raw_encoder_init(&next->coder->next, allocator, + options->filters, options->has_eopm + ? LZMA_VLI_VALUE_UNKNOWN + : options->uncompressed_size, + true); +} + + +extern lzma_ret +lzma_block_encoder_init(lzma_next_coder *next, lzma_allocator *allocator, + lzma_options_block *options) +{ + lzma_next_coder_init(block_encoder_init, next, allocator, options); +} + + +extern LZMA_API lzma_ret +lzma_block_encoder(lzma_stream *strm, lzma_options_block *options) +{ + lzma_next_strm_init(strm, block_encoder_init, options); + + strm->internal->supported_actions[LZMA_RUN] = true; + strm->internal->supported_actions[LZMA_FINISH] = true; + + return LZMA_OK; +} |