mirror of https://git.tukaani.org/xz.git
114 lines
2.8 KiB
C
114 lines
2.8 KiB
C
///////////////////////////////////////////////////////////////////////////////
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//
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/// \file auto_decoder.c
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/// \brief Autodetect between .lzma Stream and LZMA_Alone formats
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//
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// Copyright (C) 2007 Lasse Collin
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//
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// This library is free software; you can redistribute it and/or
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// modify it under the terms of the GNU Lesser General Public
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// License as published by the Free Software Foundation; either
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// version 2.1 of the License, or (at your option) any later version.
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//
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// This library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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// Lesser General Public License for more details.
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//
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///////////////////////////////////////////////////////////////////////////////
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#include "common.h"
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#include "alone_decoder.h"
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struct lzma_coder_s {
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lzma_next_coder next;
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lzma_extra **header;
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lzma_extra **footer;
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bool initialized;
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};
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static lzma_ret
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auto_decode(lzma_coder *coder, lzma_allocator *allocator,
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const uint8_t *restrict in, size_t *restrict in_pos,
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size_t in_size, uint8_t *restrict out,
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size_t *restrict out_pos, size_t out_size, lzma_action action)
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{
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if (!coder->initialized) {
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if (*in_pos >= in_size)
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return LZMA_OK;
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lzma_ret ret;
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if (in[*in_pos] == 0xFF)
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ret = lzma_stream_decoder_init(&coder->next, allocator,
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coder->header, coder->footer);
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else
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ret = lzma_alone_decoder_init(&coder->next, allocator);
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if (ret != LZMA_OK)
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return ret;
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coder->initialized = true;
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}
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return coder->next.code(coder->next.coder, allocator,
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in, in_pos, in_size, out, out_pos, out_size, action);
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}
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static void
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auto_decoder_end(lzma_coder *coder, lzma_allocator *allocator)
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{
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lzma_next_coder_end(&coder->next, allocator);
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lzma_free(coder, allocator);
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return;
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}
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static lzma_ret
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auto_decoder_init(lzma_next_coder *next, lzma_allocator *allocator,
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lzma_extra **header, lzma_extra **footer)
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{
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if (next->coder == NULL) {
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next->coder = lzma_alloc(sizeof(lzma_coder), allocator);
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if (next->coder == NULL)
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return LZMA_MEM_ERROR;
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next->code = &auto_decode;
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next->end = &auto_decoder_end;
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next->coder->next = LZMA_NEXT_CODER_INIT;
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}
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next->coder->header = header;
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next->coder->footer = footer;
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next->coder->initialized = false;
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return LZMA_OK;
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}
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/*
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extern lzma_ret
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lzma_auto_decoder_init(lzma_next_coder *next, lzma_allocator *allocator,
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lzma_extra **header, lzma_extra **footer)
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{
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lzma_next_coder_init(
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auto_decoder_init, next, allocator, header, footer);
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}
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*/
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extern LZMA_API lzma_ret
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lzma_auto_decoder(lzma_stream *strm, lzma_extra **header, lzma_extra **footer)
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{
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lzma_next_strm_init(strm, auto_decoder_init, header, footer);
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strm->internal->supported_actions[LZMA_RUN] = true;
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strm->internal->supported_actions[LZMA_SYNC_FLUSH] = true;
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return LZMA_OK;
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}
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