46 lines
1.6 KiB
C
46 lines
1.6 KiB
C
/*
|
|
* Decompression convenience functions
|
|
*
|
|
* Copyright 2007 David Gibson, IBM Corporation.
|
|
*
|
|
* This file is licensed under the terms of the GNU General Public
|
|
* License version 2. This program is licensed "as is" without any
|
|
* warranty of any kind, whether express or implied.
|
|
*/
|
|
#ifndef _PPC_BOOT_GUNZIP_UTIL_H_
|
|
#define _PPC_BOOT_GUNZIP_UTIL_H_
|
|
|
|
#include "zlib.h"
|
|
|
|
/*
|
|
* These functions are designed to make life easy for decompressing
|
|
* kernel images, initrd images or any other gzip compressed image,
|
|
* particularly if its useful to decompress part of the image (e.g. to
|
|
* examine headers) before decompressing the remainder.
|
|
*
|
|
* To use:
|
|
* - declare a gunzip_state structure
|
|
* - use gunzip_start() to initialize the state, associating it
|
|
* with a stream of compressed data
|
|
* - use gunzip_partial(), gunzip_exactly() and gunzip_discard()
|
|
* in any combination to extract pieces of data from the stream
|
|
* - Finally use gunzip_finish() to extract the tail of the
|
|
* compressed stream and wind up zlib
|
|
*/
|
|
|
|
/* scratch space for gunzip; 46912 is from zlib_inflate_workspacesize() */
|
|
#define GUNZIP_SCRATCH_SIZE 46912
|
|
|
|
struct gunzip_state {
|
|
z_stream s;
|
|
char scratch[46912];
|
|
};
|
|
|
|
void gunzip_start(struct gunzip_state *state, void *src, int srclen);
|
|
int gunzip_partial(struct gunzip_state *state, void *dst, int dstlen);
|
|
void gunzip_exactly(struct gunzip_state *state, void *dst, int len);
|
|
void gunzip_discard(struct gunzip_state *state, int len);
|
|
int gunzip_finish(struct gunzip_state *state, void *dst, int len);
|
|
|
|
#endif /* _PPC_BOOT_GUNZIP_UTIL_H_ */
|