xref: /openbmc/u-boot/lib/gunzip.c (revision 37544a6d)
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 *gzalloc(void *x, unsigned items, unsigned size)
40 {
41 	void *p;
42 
43 	size *= items;
44 	size = (size + ZALLOC_ALIGNMENT - 1) & ~(ZALLOC_ALIGNMENT - 1);
45 
46 	p = malloc (size);
47 
48 	return (p);
49 }
50 
51 void gzfree(void *x, void *addr, unsigned nb)
52 {
53 	free (addr);
54 }
55 
56 int gunzip(void *dst, int dstlen, unsigned char *src, unsigned long *lenp)
57 {
58 	int i, flags;
59 
60 	/* skip header */
61 	i = 10;
62 	flags = src[3];
63 	if (src[2] != DEFLATED || (flags & RESERVED) != 0) {
64 		puts ("Error: Bad gzipped data\n");
65 		return (-1);
66 	}
67 	if ((flags & EXTRA_FIELD) != 0)
68 		i = 12 + src[10] + (src[11] << 8);
69 	if ((flags & ORIG_NAME) != 0)
70 		while (src[i++] != 0)
71 			;
72 	if ((flags & COMMENT) != 0)
73 		while (src[i++] != 0)
74 			;
75 	if ((flags & HEAD_CRC) != 0)
76 		i += 2;
77 	if (i >= *lenp) {
78 		puts ("Error: gunzip out of data in header\n");
79 		return (-1);
80 	}
81 
82 	return zunzip(dst, dstlen, src, lenp, 1, i);
83 }
84 
85 /*
86  * Uncompress blocks compressed with zlib without headers
87  */
88 int zunzip(void *dst, int dstlen, unsigned char *src, unsigned long *lenp,
89 						int stoponerr, int offset)
90 {
91 	z_stream s;
92 	int r;
93 
94 	s.zalloc = gzalloc;
95 	s.zfree = gzfree;
96 
97 	r = inflateInit2(&s, -MAX_WBITS);
98 	if (r != Z_OK) {
99 		printf ("Error: inflateInit2() returned %d\n", r);
100 		return -1;
101 	}
102 	s.next_in = src + offset;
103 	s.avail_in = *lenp - offset;
104 	s.next_out = dst;
105 	s.avail_out = dstlen;
106 	do {
107 		r = inflate(&s, Z_FINISH);
108 		if (r != Z_STREAM_END && r != Z_BUF_ERROR && stoponerr == 1) {
109 			printf("Error: inflate() returned %d\n", r);
110 			inflateEnd(&s);
111 			return -1;
112 		}
113 		s.avail_in = *lenp - offset - (int)(s.next_out - (unsigned char*)dst);
114 		s.avail_out = dstlen;
115 	} while (r == Z_BUF_ERROR);
116 	*lenp = s.next_out - (unsigned char *) dst;
117 	inflateEnd(&s);
118 
119 	return 0;
120 }
121