diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/liblzma/common/copy_coder.c | 92 |
1 files changed, 57 insertions, 35 deletions
diff --git a/src/liblzma/common/copy_coder.c b/src/liblzma/common/copy_coder.c index 64864f60..41f327d1 100644 --- a/src/liblzma/common/copy_coder.c +++ b/src/liblzma/common/copy_coder.c @@ -23,12 +23,12 @@ struct lzma_coder_s { lzma_next_coder next; lzma_vli uncompressed_size; - bool is_encoder; }; +#ifdef HAVE_ENCODER static lzma_ret -copy_code(lzma_coder *coder, lzma_allocator *allocator, +copy_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) @@ -43,48 +43,71 @@ copy_code(lzma_coder *coder, lzma_allocator *allocator, action); // If we get here, we are the last filter in the chain. + assert(coder->uncompressed_size <= LZMA_VLI_VALUE_MAX); const size_t in_avail = in_size - *in_pos; - if (coder->is_encoder) { - // Check that we don't have too much input. - if ((lzma_vli)(in_avail) > coder->uncompressed_size) - return LZMA_DATA_ERROR; - - // Check that once LZMA_FINISH has been given, the - // amount of input matches uncompressed_size if it - // is known. - if (action == LZMA_FINISH && coder->uncompressed_size - != LZMA_VLI_VALUE_UNKNOWN - && coder->uncompressed_size - != (lzma_vli)(in_avail)) - return LZMA_DATA_ERROR; - - } else { - // Limit in_size so that we don't copy too much. - if ((lzma_vli)(in_avail) > coder->uncompressed_size) - in_size = *in_pos + (size_t)(coder->uncompressed_size); - } + // Check that we don't have too much input. + if ((lzma_vli)(in_avail) > coder->uncompressed_size) + return LZMA_DATA_ERROR; - // Store the old input position, which is needed to update - // coder->uncompressed_size. - const size_t in_start = *in_pos; + // Check that once LZMA_FINISH has been given, the amount of input + // matches uncompressed_size, which is always known. + if (action == LZMA_FINISH + && coder->uncompressed_size != (lzma_vli)(in_avail)) + return LZMA_DATA_ERROR; // We are the last coder in the chain. // Just copy as much data as possible. - bufcpy(in, in_pos, in_size, out, out_pos, out_size); + const size_t in_used = bufcpy( + in, in_pos, in_size, out, out_pos, out_size); // Update uncompressed_size if it is known. if (coder->uncompressed_size != LZMA_VLI_VALUE_UNKNOWN) - coder->uncompressed_size -= *in_pos - in_start; + coder->uncompressed_size -= in_used; - // action can be LZMA_FINISH only in the encoder. - if ((action == LZMA_FINISH && *in_pos == in_size) + // LZMA_SYNC_FLUSH and LZMA_FINISH are the same thing for us. + if ((action != LZMA_RUN && *in_pos == in_size) || coder->uncompressed_size == 0) return LZMA_STREAM_END; return LZMA_OK; } +#endif + + +#ifdef HAVE_DECODER +static lzma_ret +copy_decode(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) +{ + if (coder->next.code != NULL) + return coder->next.code(coder->next.coder, allocator, + in, in_pos, in_size, out, out_pos, out_size, + action); + + assert(coder->uncompressed_size <= LZMA_VLI_VALUE_MAX); + + const size_t in_avail = in_size - *in_pos; + + // Limit in_size so that we don't copy too much. + if ((lzma_vli)(in_avail) > coder->uncompressed_size) + in_size = *in_pos + (size_t)(coder->uncompressed_size); + + // We are the last coder in the chain. + // Just copy as much data as possible. + const size_t in_used = bufcpy( + in, in_pos, in_size, out, out_pos, out_size); + + // Update uncompressed_size if it is known. + if (coder->uncompressed_size != LZMA_VLI_VALUE_UNKNOWN) + coder->uncompressed_size -= in_used; + + return coder->uncompressed_size == 0 ? LZMA_STREAM_END : LZMA_OK; +} +#endif static void @@ -98,7 +121,7 @@ copy_coder_end(lzma_coder *coder, lzma_allocator *allocator) static lzma_ret copy_coder_init(lzma_next_coder *next, lzma_allocator *allocator, - const lzma_filter_info *filters, bool is_encoder) + const lzma_filter_info *filters, lzma_code_function encode) { // Allocate memory for the decoder if needed. if (next->coder == NULL) { @@ -106,7 +129,7 @@ copy_coder_init(lzma_next_coder *next, lzma_allocator *allocator, if (next->coder == NULL) return LZMA_MEM_ERROR; - next->code = ©_code; + next->code = encode; next->end = ©_coder_end; next->coder->next = LZMA_NEXT_CODER_INIT; } @@ -114,9 +137,6 @@ copy_coder_init(lzma_next_coder *next, lzma_allocator *allocator, // Copy Uncompressed Size which is used to limit the output size. next->coder->uncompressed_size = filters[0].uncompressed_size; - // The coder acts slightly differently as encoder and decoder. - next->coder->is_encoder = is_encoder; - // Initialize the next decoder in the chain, if any. return lzma_next_filter_init( &next->coder->next, allocator, filters + 1); @@ -128,7 +148,8 @@ extern lzma_ret lzma_copy_encoder_init(lzma_next_coder *next, lzma_allocator *allocator, const lzma_filter_info *filters) { - lzma_next_coder_init(copy_coder_init, next, allocator, filters, true); + lzma_next_coder_init(copy_coder_init, next, allocator, filters, + ©_encode); } #endif @@ -138,6 +159,7 @@ extern lzma_ret lzma_copy_decoder_init(lzma_next_coder *next, lzma_allocator *allocator, const lzma_filter_info *filters) { - lzma_next_coder_init(copy_coder_init, next, allocator, filters, false); + lzma_next_coder_init(copy_coder_init, next, allocator, filters, + ©_decode); } #endif |