flate

commit 8fba42f347be7bb505324c2d57847807a7ba26a3
parent c338151a0cb5cb8f46fb9b82e02dc90400c77e60
Author: nsz <nszabolcs@gmail.com>
Date:   Mon,  8 Jun 2009 11:26:02 +0200

renames
Diffstat:
inflate.c
 | 
39
++++++++++++++-------------------------

1 file changed, 14 insertions(+), 25 deletions(-)
diff --git a/inflate.c b/inflate.c
@@ -219,26 +219,7 @@ static void init_fixed_huffs(void) {
 	build_huff(&dhuff, lens, Ndist, 5);
 }
 
-static int fillbits(State *s, int n) {
-	while (s->nbits < n) {
-		if (s->src == s->srcend)
-			return 0;
-		s->bits |= *s->src++ << s->nbits;
-		s->nbits += 8;
-	}
-	return 1;
-}
-
-static uint getbits(State *s, int n) {
-	uint k;
-
-	k = s->bits & ((1 << n) - 1);
-	s->bits >>= n;
-	s->nbits -= n;
-	return k;
-}
-
-static int fillbits_(uchar **src, uchar *srcend, uint *bits, uint *nbits, uint n) {
+static int fillbits_fast(uchar **src, uchar *srcend, uint *bits, uint *nbits, uint n) {
 	while (*nbits < n) {
 		if (*src == srcend)
 			return 0;
@@ -248,7 +229,7 @@ static int fillbits_(uchar **src, uchar *srcend, uint *bits, uint *nbits, uint n
 	return 1;
 }
 
-static uint getbits_(uint *bits, uint *nbits, int n) {
+static uint getbits_fast(uint *bits, uint *nbits, int n) {
 	uint k;
 
 	k = *bits & ((1 << n) - 1);
@@ -257,6 +238,14 @@ static uint getbits_(uint *bits, uint *nbits, int n) {
 	return k;
 }
 
+static int fillbits(State *s, uint n) {
+	return fillbits_fast(&s->src, s->srcend, &s->bits, &s->nbits, n);
+}
+
+static uint getbits(State *s, uint n) {
+	return getbits_fast(&s->bits, &s->nbits, n);
+}
+
 /* decode symbol bitwise if code is longer than huffbits */
 static uint decode_symbol_long(State *s, Huff *huff, uint bits, uint nbits, int cur) {
 	int sum = huff->sum;
@@ -387,13 +376,13 @@ static int decode_block(State *s, Huff *lhuff, Huff *dhuff) {
 				return FlateError;
 			}
 decode_lenbits:
-			if (!fillbits_(&s->src, s->srcend, &s->bits, &s->nbits, lenbits[sym])) {
+			if (!fillbits_fast(&s->src, s->srcend, &s->bits, &s->nbits, lenbits[sym])) {
 				s->nclen = sym; /* using nclen to store sym */
 				s->pos = pos;
 				s->state = DecodeBlockLenBits;
 				return FlateNeedInput;
 			}
-			len = lenbase[sym] + getbits_(&s->bits, &s->nbits, lenbits[sym]);
+			len = lenbase[sym] + getbits_fast(&s->bits, &s->nbits, lenbits[sym]);
 decode_dist:
 			sym = decode_symbol(s, dhuff);
 			if (sym == (uint)FlateNeedInput) {
@@ -405,7 +394,7 @@ decode_dist:
 			if (sym >= Ndist)
 				return FlateError;
 decode_distbits:
-			if (!fillbits_(&s->src, s->srcend, &s->bits, &s->nbits, distbits[sym])) {
+			if (!fillbits_fast(&s->src, s->srcend, &s->bits, &s->nbits, distbits[sym])) {
 				s->nclen = sym; /* using nclen to store sym */
 				s->pos = pos;
 				s->lenpos = len;
@@ -413,7 +402,7 @@ decode_distbits:
 				return FlateNeedInput;
 			}
 			/* TODO: s/dist/sym/ */
-			dist = distbase[sym] + getbits_(&s->bits, &s->nbits, distbits[sym]);
+			dist = distbase[sym] + getbits_fast(&s->bits, &s->nbits, distbits[sym]);
 			/* copy match, loop unroll in common case */
 			if (pos + len < WinSize) {
 				/* lenbase[sym] >= 3 */