include/linux/decompress/generic.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef DECOMPRESS_GENERIC_H
   3 #define DECOMPRESS_GENERIC_H
   4
   5 typedef int (*decompress_fn) (unsigned char *inbuf, long len,
   6                               long (*fill)(void*, unsigned long),
   7                               long (*flush)(void*, unsigned long),
   8                               unsigned char *outbuf,
   9                               long *posp,
  10                               void(*error)(char *x));
  11
  12 /* inbuf   - input buffer
  13  *len     - len of pre-read data in inbuf
  14  *fill    - function to fill inbuf when empty
  15  *flush   - function to write out outbuf
  16  *outbuf  - output buffer
  17  *posp    - if non-null, input position (number of bytes read) will be
  18  *        returned here
  19  *
  20  *If len != 0, inbuf should contain all the necessary input data, and fill
  21  *should be NULL
  22  *If len = 0, inbuf can be NULL, in which case the decompressor will allocate
  23  *the input buffer.  If inbuf != NULL it must be at least XXX_IOBUF_SIZE bytes.
  24  *fill will be called (repeatedly...) to read data, at most XXX_IOBUF_SIZE
  25  *bytes should be read per call.  Replace XXX with the appropriate decompressor
  26  *name, i.e. LZMA_IOBUF_SIZE.
  27  *
  28  *If flush = NULL, outbuf must be large enough to buffer all the expected
  29  *output.  If flush != NULL, the output buffer will be allocated by the
  30  *decompressor (outbuf = NULL), and the flush function will be called to
  31  *flush the output buffer at the appropriate time (decompressor and stream
  32  *dependent).
  33  */
  34
  35
  36 /* Utility routine to detect the decompression method */
  37 decompress_fn decompress_method(const unsigned char *inbuf, long len,
  38                                 const char **name);
  39
  40 #endif