diff options
| -rw-r--r-- | src/liblzma/api/lzma/block.h | 41 | ||||
| -rw-r--r-- | src/liblzma/common/Makefile.am | 1 | ||||
| -rw-r--r-- | src/liblzma/common/block_buffer_decoder.c | 87 |
3 files changed, 129 insertions, 0 deletions
diff --git a/src/liblzma/api/lzma/block.h b/src/liblzma/api/lzma/block.h index 612cd87f..7ac0a02c 100644 --- a/src/liblzma/api/lzma/block.h +++ b/src/liblzma/api/lzma/block.h @@ -56,6 +56,7 @@ typedef struct { * - lzma_block_encoder() * - lzma_block_decoder() * - lzma_block_buffer_encode() + * - lzma_block_buffer_decode() * * Written by: * - lzma_block_header_decode() @@ -74,6 +75,7 @@ typedef struct { * - lzma_block_unpadded_size() * - lzma_block_total_size() * - lzma_block_decoder() + * - lzma_block_buffer_decode() * * Written by: * - lzma_block_header_size() @@ -98,6 +100,7 @@ typedef struct { * - lzma_block_encoder() * - lzma_block_decoder() * - lzma_block_buffer_encode() + * - lzma_block_buffer_decode() */ lzma_check check; @@ -144,6 +147,7 @@ typedef struct { * - lzma_block_unpadded_size() * - lzma_block_total_size() * - lzma_block_decoder() + * - lzma_block_buffer_decode() * * Written by: * - lzma_block_header_decode() @@ -151,6 +155,7 @@ typedef struct { * - lzma_block_encoder() * - lzma_block_decoder() * - lzma_block_buffer_encode() + * - lzma_block_buffer_decode() */ lzma_vli compressed_size; @@ -167,12 +172,14 @@ typedef struct { * - lzma_block_header_size() * - lzma_block_header_encode() * - lzma_block_decoder() + * - lzma_block_buffer_decode() * * Written by: * - lzma_block_header_decode() * - lzma_block_encoder() * - lzma_block_decoder() * - lzma_block_buffer_encode() + * - lzma_block_buffer_decode() */ lzma_vli uncompressed_size; @@ -188,6 +195,7 @@ typedef struct { * - lzma_block_encoder() * - lzma_block_decoder() * - lzma_block_buffer_encode() + * - lzma_block_buffer_decode() * * Written by: * - lzma_block_header_decode(): Note that this does NOT free() @@ -473,3 +481,36 @@ extern lzma_ret lzma_block_buffer_encode( const uint8_t *in, size_t in_size, uint8_t *out, size_t *out_pos, size_t out_size) lzma_attr_warn_unused_result; + + +/** + * \brief Single-call .xz Block decoder + * + * This is single-call equivalent of lzma_block_decoder(), and requires that + * the caller has already decoded Block Header and checked its memory usage. + * + * \param block Block options just like with lzma_block_decoder(). + * \param allocator lzma_allocator for custom allocator functions. + * Set to NULL to use malloc() and free(). + * \param in Beginning of the input buffer + * \param in_pos The next byte will be read from in[*in_pos]. + * *in_pos is updated only if decoding succeeds. + * \param in_size Size of the input buffer; the first byte that + * won't be read is in[in_size]. + * \param out Beginning of the output buffer + * \param out_pos The next byte will be written to out[*out_pos]. + * *out_pos is updated only if encoding succeeds. + * \param out_size Size of the out buffer; the first byte into + * which no data is written to is out[out_size]. + * + * \return - LZMA_OK: Decoding was successful. + * - LZMA_OPTIONS_ERROR + * - LZMA_DATA_ERROR + * - LZMA_MEM_ERROR + * - LZMA_BUF_ERROR: Output buffer was too small. + * - LZMA_PROG_ERROR + */ +extern lzma_ret lzma_block_buffer_decode( + lzma_block *block, lzma_allocator *allocator, + const uint8_t *in, size_t *in_pos, size_t in_size, + uint8_t *out, size_t *out_pos, size_t out_size); diff --git a/src/liblzma/common/Makefile.am b/src/liblzma/common/Makefile.am index e8ff480f..1496b2d0 100644 --- a/src/liblzma/common/Makefile.am +++ b/src/liblzma/common/Makefile.am @@ -61,6 +61,7 @@ libcommon_la_SOURCES += \ alone_decoder.c \ alone_decoder.h \ auto_decoder.c \ + block_buffer_decoder.c \ block_decoder.c \ block_decoder.h \ block_header_decoder.c \ diff --git a/src/liblzma/common/block_buffer_decoder.c b/src/liblzma/common/block_buffer_decoder.c new file mode 100644 index 00000000..ec24e44b --- /dev/null +++ b/src/liblzma/common/block_buffer_decoder.c @@ -0,0 +1,87 @@ +/////////////////////////////////////////////////////////////////////////////// +// +/// \file block_buffer_decoder.c +/// \brief Single-call .xz Block decoder +// +// Copyright (C) 2009 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_decoder.h" + + +extern LZMA_API lzma_ret +lzma_block_buffer_decode(lzma_block *block, lzma_allocator *allocator, + const uint8_t *in, size_t *in_pos, size_t in_size, + uint8_t *out, size_t *out_pos, size_t out_size) +{ + if (in_pos == NULL || (in == NULL && *in_pos != in_size) + || *in_pos > in_size || out_pos == NULL + || (out == NULL && *out_pos != out_size) + || *out_pos > out_size) + return LZMA_PROG_ERROR; + + // Initialize the Block decoder. + lzma_next_coder block_decoder = LZMA_NEXT_CODER_INIT; + lzma_ret ret = lzma_block_decoder_init( + &block_decoder, allocator, block); + + if (ret == LZMA_OK) { + // Save the positions so that we can restore them in case + // an error occurs. + const size_t in_start = *in_pos; + const size_t out_start = *out_pos; + + // Do the actual decoding. + ret = block_decoder.code(block_decoder.coder, allocator, + in, in_pos, in_size, out, out_pos, out_size, + LZMA_FINISH); + + if (ret == LZMA_STREAM_END) { + ret = LZMA_OK; + } else { + // Something went wrong, restore the positions. + *in_pos = in_start; + *out_pos = out_start; + + if (ret == LZMA_OK) { + // Either the input was truncated or the + // output buffer was too small. + assert(*in_pos == in_size + || *out_pos == out_size); + + // If all the input was consumed, then the + // input is truncated, even if the output + // buffer is also full. This is because + // processing the last byte of the Block + // never produces output. + // + // NOTE: This assumption may break when new + // filters are added, if the end marker of + // the filter doesn't consume at least one + // complete byte. + if (*in_pos == in_size) + ret = LZMA_DATA_ERROR; + else + ret = LZMA_BUF_ERROR; + } + } + } + + // Free the decoder memory. This needs to be done even if + // initialization fails, because the internal API doesn't + // require the initialization function to free its memory on error. + lzma_next_end(&block_decoder, allocator); + + return ret; +} |