flate

commit 2d40c927d7473c92826756c595461756bfdee095
parent 125cf4e3c02d9e3e8258f164e73dbcc316d18310
Author: nsz <nszabolcs@gmail.com>
Date:   Sun, 21 Jun 2009 21:19:52 +0200

-winmask, +todo
Diffstat:
inflate.c
 | 
18
+++++++++---------

1 file changed, 9 insertions(+), 9 deletions(-)
diff --git a/inflate.c b/inflate.c
@@ -16,8 +16,7 @@ enum {
 	Ndist           = 30,  /* number of distance codes */
 	Nclen           = 19,  /* number of code length codes */
 	SrcSize         = 1 << 12, /* input buffer size */
-	WinSize         = 1 << 15, /* output window size */
-	WinMask         = WinSize - 1 /* window pos (index) mask */
+	WinSize         = 1 << 15 /* output window size */
 };
 
 /* return values */
@@ -180,7 +179,7 @@ static int build_huff(Huff *huff, uchar *lens, uint n, uint nbits) {
 
 	/* lookup table for decoding nbits from input.. */
 	for (i = 0; i < 1 << nbits; i++)
-		table[i].len = 0; /* invalid marker for incomplete code */
+		table[i].len = table[i].sym = 0;
 	code = 0;
 	/* ..if code is at most nbits (bits are in reverse order, sigh..) */
 	for (len = min; len <= nbits; len++)
@@ -399,26 +398,26 @@ static int decode_block(State *s, Huff *lhuff, Huff *dhuff) {
 			if (pos + len < WinSize) {
 				/* lenbase[sym] >= 3 */
 				do {
-					win[pos] = win[(pos - dist) & WinMask];
+					win[pos] = win[(pos - dist) % WinSize];
 					pos++;
-					win[pos] = win[(pos - dist) & WinMask];
+					win[pos] = win[(pos - dist) % WinSize];
 					pos++;
-					win[pos] = win[(pos - dist) & WinMask];
+					win[pos] = win[(pos - dist) % WinSize];
 					pos++;
 					len -= 3;
 				} while (len >= 3);
 				if (len--) {
-					win[pos] = win[(pos - dist) & WinMask];
+					win[pos] = win[(pos - dist) % WinSize];
 					pos++;
 					if (len) {
-						win[pos] = win[(pos - dist) & WinMask];
+						win[pos] = win[(pos - dist) % WinSize];
 						pos++;
 					}
 				}
 			} else { /* rare */
 	case DecodeBlockCopy:
 				while (len--) {
-					win[pos] = win[(pos - dist) & WinMask];
+					win[pos] = win[(pos - dist) % WinSize];
 					pos++;
 					if (pos == WinSize) {
 						s->pos = pos;
@@ -567,6 +566,7 @@ int inflate(State *s) {
 					s->state = DynamicHuffContinue;
 					return FlateNeedInput;
 				}
+
 				/* TODO: bound check s->lens */
 				if (sym == 16) {
 					/* copy previous code length 3-6 times */