block/dmg-lzfse.c

   1 /*
   2  * DMG lzfse uncompression
   3  *
   4  * Copyright (c) 2018 Julio Cesar Faracco
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24 #include "qemu/osdep.h"
  25 #include "dmg.h"
  26
  27 /* Work around a -Wstrict-prototypes warning in LZFSE headers */
  28 #pragma GCC diagnostic push
  29 #pragma GCC diagnostic ignored "-Wstrict-prototypes"
  30 #include <lzfse.h>
  31 #pragma GCC diagnostic pop
  32
  33 static int dmg_uncompress_lzfse_do(char *next_in, unsigned int avail_in,
  34                                    char *next_out, unsigned int avail_out)
  35 {
  36     size_t out_size = lzfse_decode_buffer((uint8_t *) next_out, avail_out,
  37                                           (uint8_t *) next_in, avail_in,
  38                                           NULL);
  39
  40     /* We need to decode the single chunk only. */
  41     /* So, out_size == avail_out is not an error here. */
  42     if (out_size > 0) {
  43         return out_size;
  44     }
  45     return -1;
  46 }
  47
  48 __attribute__((constructor))
  49 static void dmg_lzfse_init(void)
  50 {
  51     assert(!dmg_uncompress_lzfse);
  52     dmg_uncompress_lzfse = dmg_uncompress_lzfse_do;
  53 }