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-rw-r--r--src/liblzma/common/delta_coder.c189
1 files changed, 0 insertions, 189 deletions
diff --git a/src/liblzma/common/delta_coder.c b/src/liblzma/common/delta_coder.c
deleted file mode 100644
index 9b260a01..00000000
--- a/src/liblzma/common/delta_coder.c
+++ /dev/null
@@ -1,189 +0,0 @@
-///////////////////////////////////////////////////////////////////////////////
-//
-/// \file delta_coder.c
-/// \brief Encoder and decoder for the Delta filter
-//
-// 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 "delta_coder.h"
-
-
-struct lzma_coder_s {
- /// Next coder in the chain
- lzma_next_coder next;
-
- /// Uncompressed size - This is needed when we are the last
- /// filter in the chain.
- lzma_vli uncompressed_size;
-
- /// Delta distance
- size_t distance;
-
- /// True if we are encoding; false if decoding
- bool is_encoder;
-
- /// Position in history[]
- uint8_t pos;
-
- /// Buffer to hold history of the original data
- uint8_t history[LZMA_DELTA_DISTANCE_MAX];
-};
-
-
-static void
-encode_buffer(lzma_coder *coder, uint8_t *buffer, size_t size)
-{
- const size_t distance = coder->distance;
-
- for (size_t i = 0; i < size; ++i) {
- const uint8_t tmp = coder->history[
- (distance + coder->pos) & 0xFF];
- coder->history[coder->pos--] = buffer[i];
- buffer[i] -= tmp;
- }
-
- return;
-}
-
-
-static void
-decode_buffer(lzma_coder *coder, uint8_t *buffer, size_t size)
-{
- const size_t distance = coder->distance;
-
- for (size_t i = 0; i < size; ++i) {
- buffer[i] += coder->history[(distance + coder->pos) & 0xFF];
- coder->history[coder->pos--] = buffer[i];
- }
-
- return;
-}
-
-
-static lzma_ret
-delta_code(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)
-{
- const size_t out_start = *out_pos;
- size_t size;
- lzma_ret ret;
-
- if (coder->next.code == NULL) {
- if (!coder->is_encoder) {
- // Limit in_size so that we don't copy too much.
- if ((lzma_vli)(in_size - *in_pos)
- > coder->uncompressed_size)
- in_size = *in_pos + (size_t)(
- coder->uncompressed_size);
- }
-
- size = bufcpy(in, in_pos, in_size, out, out_pos, out_size);
-
- if (coder->uncompressed_size != LZMA_VLI_VALUE_UNKNOWN)
- coder->uncompressed_size -= size;
-
- // action can be LZMA_FINISH only in the encoder.
- ret = (action == LZMA_FINISH && *in_pos == in_size)
- || coder->uncompressed_size == 0
- ? LZMA_STREAM_END : LZMA_OK;
-
- } else {
- ret = coder->next.code(coder->next.coder, allocator,
- in, in_pos, in_size, out, out_pos, out_size,
- action);
- if (ret != LZMA_OK && ret != LZMA_STREAM_END)
- return ret;
-
- size = *out_pos - out_start;
- }
-
- if (coder->is_encoder)
- encode_buffer(coder, out + out_start, size);
- else
- decode_buffer(coder, out + out_start, size);
-
- return ret;
-}
-
-
-static void
-delta_coder_end(lzma_coder *coder, lzma_allocator *allocator)
-{
- lzma_next_coder_end(&coder->next, allocator);
- lzma_free(coder, allocator);
- return;
-}
-
-
-static lzma_ret
-delta_coder_init(lzma_next_coder *next, lzma_allocator *allocator,
- const lzma_filter_info *filters, bool is_encoder)
-{
- // Allocate memory for the decoder if needed.
- if (next->coder == NULL) {
- next->coder = lzma_alloc(sizeof(lzma_coder), allocator);
- if (next->coder == NULL)
- return LZMA_MEM_ERROR;
-
- next->code = &delta_code;
- next->end = &delta_coder_end;
- next->coder->next = LZMA_NEXT_CODER_INIT;
- }
-
- // 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;
-
- // Set the delta distance.
- if (filters[0].options == NULL)
- return LZMA_PROG_ERROR;
- next->coder->distance = ((lzma_options_delta *)(filters[0].options))
- ->distance;
- if (next->coder->distance < LZMA_DELTA_DISTANCE_MIN
- || next->coder->distance > LZMA_DELTA_DISTANCE_MAX)
- return LZMA_HEADER_ERROR;
-
- // Initialize the rest of the variables.
- next->coder->pos = 0;
- memzero(next->coder->history, LZMA_DELTA_DISTANCE_MAX);
-
- // Initialize the next decoder in the chain, if any.
- return lzma_next_filter_init(&next->coder->next,
- allocator, filters + 1);
-}
-
-
-#ifdef HAVE_ENCODER
-extern lzma_ret
-lzma_delta_encoder_init(lzma_next_coder *next, lzma_allocator *allocator,
- const lzma_filter_info *filters)
-{
- return delta_coder_init(next, allocator, filters, true);
-}
-#endif
-
-
-#ifdef HAVE_DECODER
-extern lzma_ret
-lzma_delta_decoder_init(lzma_next_coder *next, lzma_allocator *allocator,
- const lzma_filter_info *filters)
-{
- return delta_coder_init(next, allocator, filters, false);
-}
-#endif