lib/gunzip.c

   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 }