diff options
author | Karl Berry <karl@freefriends.org> | 2010-06-13 22:23:34 +0000 |
---|---|---|
committer | Karl Berry <karl@freefriends.org> | 2010-06-13 22:23:34 +0000 |
commit | f06e0d7e9489163b444e1381a9e670ed1789725d (patch) | |
tree | d838b80e2b32cea0554b0a238b8344fe8059b4ad /Build/source/extra/xz/src/liblzma/common/stream_buffer_encoder.c | |
parent | 686b7eed06371a6d8721b657c0e77207732172dc (diff) |
rename to plain xz for the sake of diffs and consistent path in doc
git-svn-id: svn://tug.org/texlive/trunk@18954 c570f23f-e606-0410-a88d-b1316a301751
Diffstat (limited to 'Build/source/extra/xz/src/liblzma/common/stream_buffer_encoder.c')
-rw-r--r-- | Build/source/extra/xz/src/liblzma/common/stream_buffer_encoder.c | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/Build/source/extra/xz/src/liblzma/common/stream_buffer_encoder.c b/Build/source/extra/xz/src/liblzma/common/stream_buffer_encoder.c new file mode 100644 index 00000000000..bbafaa6d01d --- /dev/null +++ b/Build/source/extra/xz/src/liblzma/common/stream_buffer_encoder.c @@ -0,0 +1,131 @@ +/////////////////////////////////////////////////////////////////////////////// +// +/// \file stream_buffer_encoder.c +/// \brief Single-call .xz Stream encoder +// +// Author: Lasse Collin +// +// This file has been put into the public domain. +// You can do whatever you want with this file. +// +/////////////////////////////////////////////////////////////////////////////// + +#include "index.h" + + +/// Maximum size of Index that has exactly one Record. +/// Index Indicator + Number of Records + Record + CRC32 rounded up to +/// the next multiple of four. +#define INDEX_BOUND ((1 + 1 + 2 * LZMA_VLI_BYTES_MAX + 4 + 3) & ~3) + +/// Stream Header, Stream Footer, and Index +#define HEADERS_BOUND (2 * LZMA_STREAM_HEADER_SIZE + INDEX_BOUND) + + +extern LZMA_API(size_t) +lzma_stream_buffer_bound(size_t uncompressed_size) +{ + // Get the maximum possible size of a Block. + const size_t block_bound = lzma_block_buffer_bound(uncompressed_size); + if (block_bound == 0) + return 0; + + // Catch the possible integer overflow and also prevent the size of + // the Stream exceeding LZMA_VLI_MAX (theoretically possible on + // 64-bit systems). + if (MIN(SIZE_MAX, LZMA_VLI_MAX) - block_bound < HEADERS_BOUND) + return 0; + + return block_bound + HEADERS_BOUND; +} + + +extern LZMA_API(lzma_ret) +lzma_stream_buffer_encode(lzma_filter *filters, lzma_check check, + lzma_allocator *allocator, const uint8_t *in, size_t in_size, + uint8_t *out, size_t *out_pos_ptr, size_t out_size) +{ + // Sanity checks + if (filters == NULL || (unsigned int)(check) > LZMA_CHECK_ID_MAX + || (in == NULL && in_size != 0) || out == NULL + || out_pos_ptr == NULL || *out_pos_ptr > out_size) + return LZMA_PROG_ERROR; + + // Note for the paranoids: Index encoder prevents the Stream from + // getting too big and still being accepted with LZMA_OK, and Block + // encoder catches if the input is too big. So we don't need to + // separately check if the buffers are too big. + + // Use a local copy. We update *out_pos_ptr only if everything + // succeeds. + size_t out_pos = *out_pos_ptr; + + // Check that there's enough space for both Stream Header and + // Stream Footer. + if (out_size - out_pos <= 2 * LZMA_STREAM_HEADER_SIZE) + return LZMA_BUF_ERROR; + + // Reserve space for Stream Footer so we don't need to check for + // available space again before encoding Stream Footer. + out_size -= LZMA_STREAM_HEADER_SIZE; + + // Encode the Stream Header. + lzma_stream_flags stream_flags = { + .version = 0, + .check = check, + }; + + if (lzma_stream_header_encode(&stream_flags, out + out_pos) + != LZMA_OK) + return LZMA_PROG_ERROR; + + out_pos += LZMA_STREAM_HEADER_SIZE; + + // Block + lzma_block block = { + .version = 0, + .check = check, + .filters = filters, + }; + + return_if_error(lzma_block_buffer_encode(&block, allocator, + in, in_size, out, &out_pos, out_size)); + + // Index + { + // Create an Index with one Record. + lzma_index *i = lzma_index_init(allocator); + if (i == NULL) + return LZMA_MEM_ERROR; + + lzma_ret ret = lzma_index_append(i, allocator, + lzma_block_unpadded_size(&block), + block.uncompressed_size); + + // If adding the Record was successful, encode the Index + // and get its size which will be stored into Stream Footer. + if (ret == LZMA_OK) { + ret = lzma_index_buffer_encode( + i, out, &out_pos, out_size); + + stream_flags.backward_size = lzma_index_size(i); + } + + lzma_index_end(i, allocator); + + if (ret != LZMA_OK) + return ret; + } + + // Stream Footer. We have already reserved space for this. + if (lzma_stream_footer_encode(&stream_flags, out + out_pos) + != LZMA_OK) + return LZMA_PROG_ERROR; + + out_pos += LZMA_STREAM_HEADER_SIZE; + + // Everything went fine, make the new output position available + // to the application. + *out_pos_ptr = out_pos; + return LZMA_OK; +} |