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 free software; you can redistribute it and/or modify it under
  12  * the terms of the GNU Lesser General Public License as published by the Free
  13  * Software Foundation; either version 3 of the License, or (at your option) any
  14  * later version.
  15  *
  16  * This file is distributed in the hope that it will be useful, but WITHOUT
  17  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  18  * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
  19  * details.
  20  *
  21  * You should have received a copy of the GNU Lesser General Public License
  22  * along with this file; if not, see https://www.gnu.org/licenses/.
  23  */
  24
  25 #ifdef HAVE_CONFIG_H
  26 #  include "config.h"
  27 #endif
  28
  29 #include "wimlib.h"
  30 #include "wimlib/decompressor_ops.h"
  31 #include "wimlib/util.h"
  32
  33 struct wimlib_decompressor {
  34         const struct decompressor_ops *ops;
  35         size_t max_block_size;
  36         void *private;
  37 };
  38
  39 static const struct decompressor_ops * const decompressor_ops[] = {
  40         [WIMLIB_COMPRESSION_TYPE_XPRESS] = &xpress_decompressor_ops,
  41         [WIMLIB_COMPRESSION_TYPE_LZX]    = &lzx_decompressor_ops,
  42         [WIMLIB_COMPRESSION_TYPE_LZMS]   = &lzms_decompressor_ops,
  43 };
  44
  45 static bool
  46 decompressor_ctype_valid(int ctype)
  47 {
  48         return (ctype >= 0 &&
  49                 ctype < ARRAY_LEN(decompressor_ops) &&
  50                 decompressor_ops[ctype] != NULL);
  51 }
  52
  53 WIMLIBAPI int
  54 wimlib_create_decompressor(enum wimlib_compression_type ctype,
  55                            size_t max_block_size,
  56                            struct wimlib_decompressor **dec_ret)
  57 {
  58         struct wimlib_decompressor *dec;
  59         int ret;
  60
  61         ret = wimlib_global_init(0);
  62         if (ret)
  63                 return ret;
  64
  65         if (!decompressor_ctype_valid(ctype))
  66                 return WIMLIB_ERR_INVALID_COMPRESSION_TYPE;
  67
  68         if (dec_ret == NULL)
  69                 return WIMLIB_ERR_INVALID_PARAM;
  70
  71         if (max_block_size == 0)
  72                 return WIMLIB_ERR_INVALID_PARAM;
  73
  74         dec = MALLOC(sizeof(*dec));
  75         if (dec == NULL)
  76                 return WIMLIB_ERR_NOMEM;
  77         dec->ops = decompressor_ops[ctype];
  78         dec->max_block_size = max_block_size;
  79         dec->private = NULL;
  80         if (dec->ops->create_decompressor) {
  81                 ret = dec->ops->create_decompressor(max_block_size,
  82                                                     &dec->private);
  83                 if (ret) {
  84                         FREE(dec);
  85                         return ret;
  86                 }
  87         }
  88         *dec_ret = dec;
  89         return 0;
  90 }
  91
  92 WIMLIBAPI int
  93 wimlib_decompress(const void *compressed_data, size_t compressed_size,
  94                   void *uncompressed_data, size_t uncompressed_size,
  95                   struct wimlib_decompressor *dec)
  96 {
  97         if (unlikely(uncompressed_size > dec->max_block_size))
  98                 return -2;
  99
 100         return dec->ops->decompress(compressed_data, compressed_size,
 101                                     uncompressed_data, uncompressed_size,
 102                                     dec->private);
 103 }
 104
 105 WIMLIBAPI void
 106 wimlib_free_decompressor(struct wimlib_decompressor *dec)
 107 {
 108         if (dec) {
 109                 if (dec->ops->free_decompressor)
 110                         dec->ops->free_decompressor(dec->private);
 111                 FREE(dec);
 112         }
 113 }