| /////////////////////////////////////////////////////////////////////////////// |
| // |
| /// \file auto_decoder.c |
| /// \brief Autodetect between .lzma Stream and LZMA_Alone formats |
| // |
| // 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 "common.h" |
| #include "alone_decoder.h" |
| |
| |
| struct lzma_coder_s { |
| lzma_next_coder next; |
| |
| lzma_extra **header; |
| lzma_extra **footer; |
| bool initialized; |
| }; |
| |
| |
| static lzma_ret |
| auto_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->initialized) { |
| if (*in_pos >= in_size) |
| return LZMA_OK; |
| |
| lzma_ret ret; |
| |
| if (in[*in_pos] == 0xFF) |
| ret = lzma_stream_decoder_init(&coder->next, allocator, |
| coder->header, coder->footer); |
| else |
| ret = lzma_alone_decoder_init(&coder->next, allocator); |
| |
| if (ret != LZMA_OK) |
| return ret; |
| |
| coder->initialized = true; |
| } |
| |
| return coder->next.code(coder->next.coder, allocator, |
| in, in_pos, in_size, out, out_pos, out_size, action); |
| } |
| |
| |
| static void |
| auto_decoder_end(lzma_coder *coder, lzma_allocator *allocator) |
| { |
| lzma_next_coder_end(&coder->next, allocator); |
| lzma_free(coder, allocator); |
| return; |
| } |
| |
| |
| static lzma_ret |
| auto_decoder_init(lzma_next_coder *next, lzma_allocator *allocator, |
| lzma_extra **header, lzma_extra **footer) |
| { |
| if (next->coder == NULL) { |
| next->coder = lzma_alloc(sizeof(lzma_coder), allocator); |
| if (next->coder == NULL) |
| return LZMA_MEM_ERROR; |
| |
| next->code = &auto_decode; |
| next->end = &auto_decoder_end; |
| next->coder->next = LZMA_NEXT_CODER_INIT; |
| } |
| |
| next->coder->header = header; |
| next->coder->footer = footer; |
| next->coder->initialized = false; |
| |
| return LZMA_OK; |
| } |
| |
| |
| /* |
| extern lzma_ret |
| lzma_auto_decoder_init(lzma_next_coder *next, lzma_allocator *allocator, |
| lzma_extra **header, lzma_extra **footer) |
| { |
| lzma_next_coder_init( |
| auto_decoder_init, next, allocator, header, footer); |
| } |
| */ |
| |
| |
| extern LZMA_API lzma_ret |
| lzma_auto_decoder(lzma_stream *strm, lzma_extra **header, lzma_extra **footer) |
| { |
| lzma_next_strm_init(strm, auto_decoder_init, header, footer); |
| |
| strm->internal->supported_actions[LZMA_RUN] = true; |
| strm->internal->supported_actions[LZMA_SYNC_FLUSH] = true; |
| |
| return LZMA_OK; |
| } |