80 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			80 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #include <linux/zlib.h>
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| 
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| /* bits taken from ppc */
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| 
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| extern void *avail_ram, *end_avail;
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| 
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| void exit (void)
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| {
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|   for (;;);
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| }
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| 
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| void *zalloc(unsigned size)
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| {
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|         void *p = avail_ram;
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| 
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|         size = (size + 7) & -8;
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|         avail_ram += size;
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|         if (avail_ram > end_avail) {
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|                 //puts("oops... out of memory\n");
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|                 //pause();
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|                 exit ();
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|         }
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|         return p;
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| }
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| 
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| #define HEAD_CRC        2
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| #define EXTRA_FIELD     4
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| #define ORIG_NAME       8
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| #define COMMENT         0x10
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| #define RESERVED        0xe0
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| 
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| #define DEFLATED        8
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| 
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| void gunzip (void *dst, int dstlen, unsigned char *src, int *lenp)
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| {
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| 	z_stream s;
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| 	int r, i, flags;
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| 
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|         /* skip header */
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|         i = 10;
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|         flags = src[3];
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|         if (src[2] != DEFLATED || (flags & RESERVED) != 0) {
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|                 //puts("bad gzipped data\n");
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|                 exit();
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|         }
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|         if ((flags & EXTRA_FIELD) != 0)
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|                 i = 12 + src[10] + (src[11] << 8);
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|         if ((flags & ORIG_NAME) != 0)
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|                 while (src[i++] != 0)
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|                         ;
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|         if ((flags & COMMENT) != 0)
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|                 while (src[i++] != 0)
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|                         ;
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|         if ((flags & HEAD_CRC) != 0)
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|                 i += 2;
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|         if (i >= *lenp) {
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|                 //puts("gunzip: ran out of data in header\n");
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|                 exit();
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|         }
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| 
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| 	s.workspace = zalloc(zlib_inflate_workspacesize());
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|         r = zlib_inflateInit2(&s, -MAX_WBITS);
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|         if (r != Z_OK) {
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|                 //puts("inflateInit2 returned "); puthex(r); puts("\n");
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|                 exit();
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|         }
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|         s.next_in = src + i;
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|         s.avail_in = *lenp - i;
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|         s.next_out = dst;
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|         s.avail_out = dstlen;
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|         r = zlib_inflate(&s, Z_FINISH);
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|         if (r != Z_OK && r != Z_STREAM_END) {
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|                 //puts("inflate returned "); puthex(r); puts("\n");
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|                 exit();
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|         }
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|         *lenp = s.next_out - (unsigned char *) dst;
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|         zlib_inflateEnd(&s);
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| }
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| 
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