xref: /openbmc/u-boot/fs/cramfs/uncompress.c (revision ee52b188)
1 /*
2  * uncompress.c
3  *
4  * Copyright (C) 1999 Linus Torvalds
5  * Copyright (C) 2000-2002 Transmeta Corporation
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License (Version 2) as
9  * published by the Free Software Foundation.
10  *
11  * cramfs interfaces to the uncompression library. There's really just
12  * three entrypoints:
13  *
14  *  - cramfs_uncompress_init() - called to initialize the thing.
15  *  - cramfs_uncompress_exit() - tell me when you're done
16  *  - cramfs_uncompress_block() - uncompress a block.
17  *
18  * NOTE NOTE NOTE! The uncompression is entirely single-threaded. We
19  * only have one stream, and we'll initialize it only once even if it
20  * then is used by multiple filesystems.
21  */
22 
23 #include <common.h>
24 #include <malloc.h>
25 #include <watchdog.h>
26 #include <u-boot/zlib.h>
27 
28 static z_stream stream;
29 
30 /* Returns length of decompressed data. */
31 int cramfs_uncompress_block (void *dst, void *src, int srclen)
32 {
33 	int err;
34 
35 	inflateReset (&stream);
36 
37 	stream.next_in = src;
38 	stream.avail_in = srclen;
39 
40 	stream.next_out = dst;
41 	stream.avail_out = 4096 * 2;
42 
43 	err = inflate (&stream, Z_FINISH);
44 
45 	if (err != Z_STREAM_END)
46 		goto err;
47 	return stream.total_out;
48 
49       err:
50 	/*printf ("Error %d while decompressing!\n", err); */
51 	/*printf ("%p(%d)->%p\n", src, srclen, dst); */
52 	return -1;
53 }
54 
55 int cramfs_uncompress_init (void)
56 {
57 	int err;
58 
59 	stream.zalloc = gzalloc;
60 	stream.zfree = gzfree;
61 	stream.next_in = 0;
62 	stream.avail_in = 0;
63 
64 #if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
65 	stream.outcb = (cb_func) WATCHDOG_RESET;
66 #else
67 	stream.outcb = Z_NULL;
68 #endif /* CONFIG_HW_WATCHDOG */
69 
70 	err = inflateInit (&stream);
71 	if (err != Z_OK) {
72 		printf ("Error: inflateInit2() returned %d\n", err);
73 		return -1;
74 	}
75 
76 	return 0;
77 }
78 
79 int cramfs_uncompress_exit (void)
80 {
81 	inflateEnd (&stream);
82 	return 0;
83 }
84