Index: xz/src/liblzma/common/block_encoder.c |
=================================================================== |
--- xz/src/liblzma/common/block_encoder.c (revision 0) |
+++ xz/src/liblzma/common/block_encoder.c (revision 0) |
@@ -0,0 +1,212 @@ |
+/////////////////////////////////////////////////////////////////////////////// |
+// |
+/// \file block_encoder.c |
+/// \brief Encodes .xz Blocks |
+// |
+// Author: Lasse Collin |
+// |
+// This file has been put into the public domain. |
+// You can do whatever you want with this file. |
+// |
+/////////////////////////////////////////////////////////////////////////////// |
+ |
+#include "block_encoder.h" |
+#include "filter_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 Unpadded Size, Compressed Size, |
+ /// and Uncompressed Size back to this structure when the encoding |
+ /// has been finished. |
+ lzma_block *block; |
+ |
+ enum { |
+ SEQ_CODE, |
+ SEQ_PADDING, |
+ SEQ_CHECK, |
+ } sequence; |
+ |
+ /// Compressed Size calculated while encoding |
+ lzma_vli compressed_size; |
+ |
+ /// Uncompressed Size calculated while encoding |
+ lzma_vli uncompressed_size; |
+ |
+ /// Position in the Check field |
+ size_t pos; |
+ |
+ /// Check of the uncompressed data |
+ lzma_check_state check; |
+}; |
+ |
+ |
+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 (LZMA_VLI_MAX - coder->uncompressed_size < in_size - *in_pos) |
+ return LZMA_DATA_ERROR; |
+ |
+ 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 (COMPRESSED_SIZE_MAX - coder->compressed_size < out_used) |
+ return LZMA_DATA_ERROR; |
+ |
+ coder->compressed_size += out_used; |
+ |
+ // 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->block->check, |
+ in + in_start, in_used); |
+ |
+ if (ret != LZMA_STREAM_END || action == LZMA_SYNC_FLUSH) |
+ return ret; |
+ |
+ assert(*in_pos == in_size); |
+ assert(action == LZMA_FINISH); |
+ |
+ // Copy the values into coder->block. The caller |
+ // may use this information to construct Index. |
+ coder->block->compressed_size = coder->compressed_size; |
+ coder->block->uncompressed_size = coder->uncompressed_size; |
+ |
+ coder->sequence = SEQ_PADDING; |
+ } |
+ |
+ // Fall through |
+ |
+ case SEQ_PADDING: |
+ // Pad Compressed Data to a multiple of four bytes. We can |
+ // use coder->compressed_size for this since we don't need |
+ // it for anything else anymore. |
+ while (coder->compressed_size & 3) { |
+ if (*out_pos >= out_size) |
+ return LZMA_OK; |
+ |
+ out[*out_pos] = 0x00; |
+ ++*out_pos; |
+ ++coder->compressed_size; |
+ } |
+ |
+ if (coder->block->check == LZMA_CHECK_NONE) |
+ return LZMA_STREAM_END; |
+ |
+ lzma_check_finish(&coder->check, coder->block->check); |
+ |
+ coder->sequence = SEQ_CHECK; |
+ |
+ // Fall through |
+ |
+ case SEQ_CHECK: { |
+ const size_t check_size = lzma_check_size(coder->block->check); |
+ lzma_bufcpy(coder->check.buffer.u8, &coder->pos, check_size, |
+ out, out_pos, out_size); |
+ if (coder->pos < check_size) |
+ return LZMA_OK; |
+ |
+ memcpy(coder->block->raw_check, coder->check.buffer.u8, |
+ check_size); |
+ return LZMA_STREAM_END; |
+ } |
+ } |
+ |
+ return LZMA_PROG_ERROR; |
+} |
+ |
+ |
+static void |
+block_encoder_end(lzma_coder *coder, lzma_allocator *allocator) |
+{ |
+ lzma_next_end(&coder->next, allocator); |
+ lzma_free(coder, allocator); |
+ return; |
+} |
+ |
+ |
+static lzma_ret |
+block_encoder_update(lzma_coder *coder, lzma_allocator *allocator, |
+ const lzma_filter *filters lzma_attribute((unused)), |
+ const lzma_filter *reversed_filters) |
+{ |
+ if (coder->sequence != SEQ_CODE) |
+ return LZMA_PROG_ERROR; |
+ |
+ return lzma_next_filter_update( |
+ &coder->next, allocator, reversed_filters); |
+} |
+ |
+ |
+extern lzma_ret |
+lzma_block_encoder_init(lzma_next_coder *next, lzma_allocator *allocator, |
+ lzma_block *block) |
+{ |
+ lzma_next_coder_init(&lzma_block_encoder_init, next, allocator); |
+ |
+ if (block->version != 0) |
+ return LZMA_OPTIONS_ERROR; |
+ |
+ // If the Check ID is not supported, we cannot calculate the check and |
+ // thus not create a proper Block. |
+ if ((unsigned int)(block->check) > LZMA_CHECK_ID_MAX) |
+ return LZMA_PROG_ERROR; |
+ |
+ if (!lzma_check_is_supported(block->check)) |
+ return LZMA_UNSUPPORTED_CHECK; |
+ |
+ // 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->update = &block_encoder_update; |
+ next->coder->next = LZMA_NEXT_CODER_INIT; |
+ } |
+ |
+ // Basic initializations |
+ next->coder->sequence = SEQ_CODE; |
+ next->coder->block = block; |
+ next->coder->compressed_size = 0; |
+ next->coder->uncompressed_size = 0; |
+ next->coder->pos = 0; |
+ |
+ // Initialize the check |
+ lzma_check_init(&next->coder->check, block->check); |
+ |
+ // Initialize the requested filters. |
+ return lzma_raw_encoder_init(&next->coder->next, allocator, |
+ block->filters); |
+} |
+ |
+ |
+extern LZMA_API(lzma_ret) |
+lzma_block_encoder(lzma_stream *strm, lzma_block *block) |
+{ |
+ lzma_next_strm_init(lzma_block_encoder_init, strm, block); |
+ |
+ strm->internal->supported_actions[LZMA_RUN] = true; |
+ strm->internal->supported_actions[LZMA_FINISH] = true; |
+ |
+ return LZMA_OK; |
+} |
Property changes on: xz/src/liblzma/common/block_encoder.c |
___________________________________________________________________ |
Added: svn:eol-style |
+ LF |