xref: /openbmc/u-boot/lib/gunzip.c (revision f4ef6668)
1 /*
2  * (C) Copyright 2000-2006
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * See file CREDITS for list of people who contributed to this
6  * project.
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 of
11  * the License, or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21  * MA 02111-1307 USA
22  */
23 
24 #include <common.h>
25 #include <watchdog.h>
26 #include <command.h>
27 #include <image.h>
28 #include <malloc.h>
29 #include <u-boot/zlib.h>
30 
31 #define	ZALLOC_ALIGNMENT	16
32 #define HEAD_CRC		2
33 #define EXTRA_FIELD		4
34 #define ORIG_NAME		8
35 #define COMMENT			0x10
36 #define RESERVED		0xe0
37 #define DEFLATED		8
38 
39 void *zalloc(void *, unsigned, unsigned);
40 void zfree(void *, void *, unsigned);
41 
42 void *zalloc(void *x, unsigned items, unsigned size)
43 {
44 	void *p;
45 
46 	size *= items;
47 	size = (size + ZALLOC_ALIGNMENT - 1) & ~(ZALLOC_ALIGNMENT - 1);
48 
49 	p = malloc (size);
50 
51 	return (p);
52 }
53 
54 void zfree(void *x, void *addr, unsigned nb)
55 {
56 	free (addr);
57 }
58 
59 int gunzip(void *dst, int dstlen, unsigned char *src, unsigned long *lenp)
60 {
61 	int i, flags;
62 
63 	/* skip header */
64 	i = 10;
65 	flags = src[3];
66 	if (src[2] != DEFLATED || (flags & RESERVED) != 0) {
67 		puts ("Error: Bad gzipped data\n");
68 		return (-1);
69 	}
70 	if ((flags & EXTRA_FIELD) != 0)
71 		i = 12 + src[10] + (src[11] << 8);
72 	if ((flags & ORIG_NAME) != 0)
73 		while (src[i++] != 0)
74 			;
75 	if ((flags & COMMENT) != 0)
76 		while (src[i++] != 0)
77 			;
78 	if ((flags & HEAD_CRC) != 0)
79 		i += 2;
80 	if (i >= *lenp) {
81 		puts ("Error: gunzip out of data in header\n");
82 		return (-1);
83 	}
84 
85 	return zunzip(dst, dstlen, src, lenp, 1, i);
86 }
87 
88 /*
89  * Uncompress blocks compressed with zlib without headers
90  */
91 int zunzip(void *dst, int dstlen, unsigned char *src, unsigned long *lenp,
92 						int stoponerr, int offset)
93 {
94 	z_stream s;
95 	int r;
96 
97 	s.zalloc = zalloc;
98 	s.zfree = zfree;
99 
100 	r = inflateInit2(&s, -MAX_WBITS);
101 	if (r != Z_OK) {
102 		printf ("Error: inflateInit2() returned %d\n", r);
103 		return -1;
104 	}
105 	s.next_in = src + offset;
106 	s.avail_in = *lenp - offset;
107 	s.next_out = dst;
108 	s.avail_out = dstlen;
109 	do {
110 		r = inflate(&s, Z_FINISH);
111 		if (r != Z_STREAM_END && r != Z_BUF_ERROR && stoponerr == 1) {
112 			printf("Error: inflate() returned %d\n", r);
113 			inflateEnd(&s);
114 			return -1;
115 		}
116 		s.avail_in = *lenp - offset - (int)(s.next_out - (unsigned char*)dst);
117 		s.avail_out = dstlen;
118 	} while (r == Z_BUF_ERROR);
119 	*lenp = s.next_out - (unsigned char *) dst;
120 	inflateEnd(&s);
121 
122 	return 0;
123 }
124