From: Willy Tarreau <w@1wt.eu>
Date: Wed, 5 Feb 2020 14:28:55 +0000 (+0100)
Subject: CLEANUP: hpack: remove a redundant test in the decoder
X-Git-Tag: v2.2-dev2~38
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=077d366ef7d09d2284ddea9f787cfce4ed4d3ba0;p=thirdparty%2Fhaproxy.git

CLEANUP: hpack: remove a redundant test in the decoder

As reported in issue #485 the test for !len at the end of the
loop in get_var_int() is useless since it was already done inside
the loop. Actually the code is more readable if we remove the first
one so let's do this instead. The resulting code is exactly the same
since the compiler already optimized the test away.
---

diff --git a/src/hpack-dec.c b/src/hpack-dec.c
index 7f3e7624b9..a721fadc46 100644
--- a/src/hpack-dec.c
+++ b/src/hpack-dec.c
@@ -65,11 +65,7 @@ static uint32_t get_var_int(const uint8_t **raw_in, uint32_t *len_in, int b)
 	if (ret != (uint32_t)((1 << b) - 1))
 		goto end;
 
-	while (1) {
-		if (!len)
-			goto too_short;
-		if (!(*raw & 128))
-			break;
+	while (len && (*raw & 128)) {
 		ret += ((uint32_t)(*raw++) & 127) << shift;
 		shift += 7;
 		len--;