src/liblzma/common/easy.c

   1 ///////////////////////////////////////////////////////////////////////////////
   2 //
   3 /// \file       easy.c
   4 /// \brief      Easy Stream encoder initialization
   5 //
   6 //  Copyright (C) 2008 Lasse Collin
   7 //
   8 //  This library is free software; you can redistribute it and/or
   9 //  modify it under the terms of the GNU Lesser General Public
  10 //  License as published by the Free Software Foundation; either
  11 //  version 2.1 of the License, or (at your option) any later version.
  12 //
  13 //  This library is distributed in the hope that it will be useful,
  14 //  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 //  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16 //  Lesser General Public License for more details.
  17 //
  18 ///////////////////////////////////////////////////////////////////////////////
  19
  20 #include "stream_encoder.h"
  21
  22
  23 struct lzma_coder_s {
  24         lzma_next_coder stream_encoder;
  25
  26         /// We need to keep the filters array available in case
  27         /// LZMA_FULL_FLUSH is used.
  28         lzma_options_filter filters[5];
  29 };
  30
  31
  32 static bool
  33 easy_set_filters(lzma_options_filter *filters, uint32_t level)
  34 {
  35         bool error = false;
  36
  37         if (level == 0) {
  38                 // TODO FIXME Use Subblock or LZMA2 with no compression.
  39                 error = true;
  40
  41 #ifdef HAVE_FILTER_LZMA
  42         } else if (level <= 9) {
  43                 filters[0].id = LZMA_FILTER_LZMA;
  44                 filters[0].options = (void *)(&lzma_preset_lzma[level - 1]);
  45                 filters[1].id = LZMA_VLI_VALUE_UNKNOWN;
  46 #endif
  47
  48         } else {
  49                 error = true;
  50         }
  51
  52         return error;
  53 }
  54
  55
  56 static lzma_ret
  57 easy_encode(lzma_coder *coder, lzma_allocator *allocator,
  58                 const uint8_t *restrict in, size_t *restrict in_pos,
  59                 size_t in_size, uint8_t *restrict out,
  60                 size_t *restrict out_pos, size_t out_size, lzma_action action)
  61 {
  62         return coder->stream_encoder.code(
  63                         coder->stream_encoder.coder, allocator,
  64                         in, in_pos, in_size, out, out_pos, out_size, action);
  65 }
  66
  67
  68 static void
  69 easy_encoder_end(lzma_coder *coder, lzma_allocator *allocator)
  70 {
  71         lzma_next_coder_end(&coder->stream_encoder, allocator);
  72         lzma_free(coder, allocator);
  73         return;
  74 }
  75
  76
  77 static lzma_ret
  78 easy_encoder_init(lzma_next_coder *next, lzma_allocator *allocator,
  79                 lzma_easy_level level)
  80 {
  81         if (next->coder == NULL) {
  82                 next->coder = lzma_alloc(sizeof(lzma_coder), allocator);
  83                 if (next->coder == NULL)
  84                         return LZMA_MEM_ERROR;
  85
  86                 next->code = &easy_encode;
  87                 next->end = &easy_encoder_end;
  88
  89                 next->coder->stream_encoder = LZMA_NEXT_CODER_INIT;
  90         }
  91
  92         if (easy_set_filters(next->coder->filters, level))
  93                 return LZMA_HEADER_ERROR;
  94
  95         return lzma_stream_encoder_init(&next->coder->stream_encoder,
  96                         allocator, next->coder->filters, LZMA_CHECK_CRC32);
  97 }
  98
  99
 100 extern LZMA_API lzma_ret
 101 lzma_easy_encoder(lzma_stream *strm, lzma_easy_level level)
 102 {
 103         lzma_next_strm_init(strm, easy_encoder_init, level);
 104
 105         strm->internal->supported_actions[LZMA_RUN] = true;
 106         strm->internal->supported_actions[LZMA_SYNC_FLUSH] = true;
 107         strm->internal->supported_actions[LZMA_FULL_FLUSH] = true;
 108         strm->internal->supported_actions[LZMA_FINISH] = true;
 109
 110         return LZMA_OK;
 111 }
 112
 113
 114 extern LZMA_API uint32_t
 115 lzma_easy_memory_usage(lzma_easy_level level)
 116 {
 117         lzma_options_filter filters[5];
 118         if (easy_set_filters(filters, level))
 119                 return UINT32_MAX;
 120
 121         return lzma_memory_usage(filters, true);
 122 }