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         /// Options for LZMA2
  27         lzma_options_lzma opt_lzma;
  28
  29         /// We need to keep the filters array available in case
  30         /// LZMA_FULL_FLUSH is used.
  31         lzma_filter filters[5];
  32 };
  33
  34
  35 static bool
  36 easy_set_filters(lzma_coder *coder, uint32_t level)
  37 {
  38         bool error = false;
  39
  40         if (level == 0) {
  41                 // TODO FIXME Use Subblock or LZMA2 with no compression.
  42                 error = true;
  43
  44 #ifdef HAVE_ENCODER_LZMA2
  45         } else if (level <= 9) {
  46                 error = lzma_lzma_preset(&coder->opt_lzma, level - 1);
  47                 coder->filters[0].id = LZMA_FILTER_LZMA2;
  48                 coder->filters[0].options = &coder->opt_lzma;
  49                 coder->filters[1].id = LZMA_VLI_UNKNOWN;
  50 #endif
  51
  52         } else {
  53                 error = true;
  54         }
  55
  56         return error;
  57 }
  58
  59
  60 static lzma_ret
  61 easy_encode(lzma_coder *coder, lzma_allocator *allocator,
  62                 const uint8_t *restrict in, size_t *restrict in_pos,
  63                 size_t in_size, uint8_t *restrict out,
  64                 size_t *restrict out_pos, size_t out_size, lzma_action action)
  65 {
  66         return coder->stream_encoder.code(
  67                         coder->stream_encoder.coder, allocator,
  68                         in, in_pos, in_size, out, out_pos, out_size, action);
  69 }
  70
  71
  72 static void
  73 easy_encoder_end(lzma_coder *coder, lzma_allocator *allocator)
  74 {
  75         lzma_next_end(&coder->stream_encoder, allocator);
  76         lzma_free(coder, allocator);
  77         return;
  78 }
  79
  80
  81 static lzma_ret
  82 easy_encoder_init(lzma_next_coder *next, lzma_allocator *allocator,
  83                 lzma_easy_level level)
  84 {
  85         lzma_next_coder_init(easy_encoder_init, next, allocator);
  86
  87         if (next->coder == NULL) {
  88                 next->coder = lzma_alloc(sizeof(lzma_coder), allocator);
  89                 if (next->coder == NULL)
  90                         return LZMA_MEM_ERROR;
  91
  92                 next->code = &easy_encode;
  93                 next->end = &easy_encoder_end;
  94
  95                 next->coder->stream_encoder = LZMA_NEXT_CODER_INIT;
  96         }
  97
  98         if (easy_set_filters(next->coder, level))
  99                 return LZMA_OPTIONS_ERROR;
 100
 101         return lzma_stream_encoder_init(&next->coder->stream_encoder,
 102                         allocator, next->coder->filters, LZMA_CHECK_CRC32);
 103 }
 104
 105
 106 extern LZMA_API lzma_ret
 107 lzma_easy_encoder(lzma_stream *strm, lzma_easy_level level)
 108 {
 109         lzma_next_strm_init(easy_encoder_init, strm, level);
 110
 111         strm->internal->supported_actions[LZMA_RUN] = true;
 112         strm->internal->supported_actions[LZMA_SYNC_FLUSH] = true;
 113         strm->internal->supported_actions[LZMA_FULL_FLUSH] = true;
 114         strm->internal->supported_actions[LZMA_FINISH] = true;
 115
 116         return LZMA_OK;
 117 }
 118
 119
 120 extern LZMA_API uint64_t
 121 lzma_easy_memory_usage(lzma_easy_level level)
 122 {
 123         lzma_coder coder;
 124         if (easy_set_filters(&coder, level))
 125                 return UINT32_MAX;
 126
 127         return lzma_memusage_encoder(coder.filters);
 128 }