xref: /openbmc/u-boot/fs/cramfs/uncompress.c (revision 461fa68d)
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 <zlib.h>
27 
28 #if defined(CONFIG_CMD_CRAMFS)
29 
30 static z_stream stream;
31 
32 void *zalloc(void *, unsigned, unsigned);
33 void zfree(void *, void *, unsigned);
34 
35 /* Returns length of decompressed data. */
36 int cramfs_uncompress_block (void *dst, void *src, int srclen)
37 {
38 	int err;
39 
40 	inflateReset (&stream);
41 
42 	stream.next_in = src;
43 	stream.avail_in = srclen;
44 
45 	stream.next_out = dst;
46 	stream.avail_out = 4096 * 2;
47 
48 	err = inflate (&stream, Z_FINISH);
49 
50 	if (err != Z_STREAM_END)
51 		goto err;
52 	return stream.total_out;
53 
54       err:
55 	/*printf ("Error %d while decompressing!\n", err); */
56 	/*printf ("%p(%d)->%p\n", src, srclen, dst); */
57 	return -1;
58 }
59 
60 int cramfs_uncompress_init (void)
61 {
62 	int err;
63 
64 	stream.zalloc = zalloc;
65 	stream.zfree = zfree;
66 	stream.next_in = 0;
67 	stream.avail_in = 0;
68 
69 #if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
70 	stream.outcb = (cb_func) WATCHDOG_RESET;
71 #else
72 	stream.outcb = Z_NULL;
73 #endif /* CONFIG_HW_WATCHDOG */
74 
75 	err = inflateInit (&stream);
76 	if (err != Z_OK) {
77 		printf ("Error: inflateInit2() returned %d\n", err);
78 		return -1;
79 	}
80 
81 	return 0;
82 }
83 
84 int cramfs_uncompress_exit (void)
85 {
86 	inflateEnd (&stream);
87 	return 0;
88 }
89 
90 #endif /* CFG_FS_CRAMFS */
91