/*  * This file is part of the UCB release of Plan 9. It is subject to the license * terms in the LICENSE file found in the top-level directory of this * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No * part of the UCB release of Plan 9, including this file, may be copied, * modified, propagated, or distributed except according to the terms contained * in the LICENSE file. */ #include <u.h>#include <libc.h>#include <flate.h>#include "zlib.h" typedef struct Block	Block; struct Block{	uchar	*pos;	uchar	*limit;}; static intblgetc(void *vb){	Block *b; 	b = vb;	if(b->pos >= b->limit)		return -1;	return *b->pos++;} static intblwrite(void *vb, void *buf, int n){	Block *b; 	b = vb; 	if(n > b->limit - b->pos)		n = b->limit - b->pos;	memmove(b->pos, buf, n);	b->pos += n;	return n;} intinflatezlibblock(uchar *dst, int dsize, uchar *src, int ssize){	Block bd, bs;	int ok; 	if(ssize < 6)		return FlateInputFail; 	if(((src[0] << 8) | src[1]) % 31)		return FlateCorrupted;	if((src[0] & ZlibMeth) != ZlibDeflate	|| (src[0] & ZlibCInfo) > ZlibWin32k)		return FlateCorrupted; 	bs.pos = src + 2;	bs.limit = src + ssize - 6; 	bd.pos = dst;	bd.limit = dst + dsize; 	ok = inflate(&bd, blwrite, &bs, blgetc);	if(ok != FlateOk)		return ok; 	if(adler32(1, dst, bs.pos - dst) != ((bs.pos[0] << 24) | (bs.pos[1] << 16) | (bs.pos[2] << 8) | bs.pos[3]))		return FlateCorrupted; 	return bd.pos - dst;}