wimlib.net Git - wimlib/blob - src/decompress.c

   1 /*
   2  * decompress.c
   3  *
   4  * Generic functions for decompression, wrapping around actual decompression
   5  * implementations.
   6  */
   7
   8 /*
   9  * Copyright (C) 2013, 2014 Eric Biggers
  10  *
  11  * This file is part of wimlib, a library for working with WIM files.
  12  *
  13  * wimlib is free software; you can redistribute it and/or modify it under the
  14  * terms of the GNU General Public License as published by the Free
  15  * Software Foundation; either version 3 of the License, or (at your option)
  16  * any later version.
  17  *
  18  * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY
  19  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
  20  * A PARTICULAR PURPOSE. See the GNU General Public License for more
  21  * details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with wimlib; if not, see http://www.gnu.org/licenses/.
  25  */
  26
  27 #ifdef HAVE_CONFIG_H
  28 #  include "config.h"
  29 #endif
  30
  31 #include "wimlib.h"
  32 #include "wimlib/decompressor_ops.h"
  33 #include "wimlib/util.h"
  34
  35 struct wimlib_decompressor {
  36         const struct decompressor_ops *ops;
  37         size_t max_block_size;
  38         void *private;
  39 };
  40
  41 static const struct decompressor_ops *decompressor_ops[] = {
  42         [WIMLIB_COMPRESSION_TYPE_XPRESS] = &xpress_decompressor_ops,
  43         [WIMLIB_COMPRESSION_TYPE_LZX]    = &lzx_decompressor_ops,
  44         [WIMLIB_COMPRESSION_TYPE_LZMS]   = &lzms_decompressor_ops,
  45 };
  46
  47 static bool
  48 decompressor_ctype_valid(int ctype)
  49 {
  50         return (ctype >= 0 &&
  51                 ctype < ARRAY_LEN(decompressor_ops) &&
  52                 decompressor_ops[ctype] != NULL);
  53 }
  54
  55 WIMLIBAPI int
  56 wimlib_create_decompressor(enum wimlib_compression_type ctype,
  57                            size_t max_block_size,
  58                            struct wimlib_decompressor **dec_ret)
  59 {
  60         struct wimlib_decompressor *dec;
  61
  62         if (dec_ret == NULL)
  63                 return WIMLIB_ERR_INVALID_PARAM;
  64
  65         if (!decompressor_ctype_valid(ctype))
  66                 return WIMLIB_ERR_INVALID_COMPRESSION_TYPE;
  67
  68         dec = MALLOC(sizeof(*dec));
  69         if (dec == NULL)
  70                 return WIMLIB_ERR_NOMEM;
  71         dec->ops = decompressor_ops[ctype];
  72         dec->max_block_size = max_block_size;
  73         dec->private = NULL;
  74         if (dec->ops->create_decompressor) {
  75                 int ret;
  76
  77                 ret = dec->ops->create_decompressor(max_block_size,
  78                                                     &dec->private);
  79                 if (ret) {
  80                         FREE(dec);
  81                         return ret;
  82                 }
  83         }
  84         *dec_ret = dec;
  85         return 0;
  86 }
  87
  88 WIMLIBAPI int
  89 wimlib_decompress(const void *compressed_data, size_t compressed_size,
  90                   void *uncompressed_data, size_t uncompressed_size,
  91                   struct wimlib_decompressor *dec)
  92 {
  93         if (unlikely(uncompressed_size > dec->max_block_size))
  94                 return -2;
  95
  96         return dec->ops->decompress(compressed_data, compressed_size,
  97                                     uncompressed_data, uncompressed_size,
  98                                     dec->private);
  99 }
 100
 101 WIMLIBAPI void
 102 wimlib_free_decompressor(struct wimlib_decompressor *dec)
 103 {
 104         if (dec) {
 105                 if (dec->ops->free_decompressor)
 106                         dec->ops->free_decompressor(dec->private);
 107                 FREE(dec);
 108         }
 109 }