From: Amaury Denoyelle <adenoyelle@haproxy.com>
Date: Wed, 13 May 2026 06:02:09 +0000 (+0200)
Subject: MINOR: h2: explain committed_extra_streams dec on h2_init() error
X-Git-Tag: v3.4-dev13~23
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=ad3562fea189c6473de3568b2bcd03587c4b5813;p=thirdparty%2Fhaproxy.git

MINOR: h2: explain committed_extra_streams dec on h2_init() error

h2_init() is now responsible to increment committed_extra_streams for
new frontend connections, in relation to the newly implemented
stream-elasticity feature. In case of an early error, a mirroring
decrement is executed on fail_stream label.

However, for now this error label can only be selected via BE conns. In
fact, it's not yet possible for h2_init() to fail after the extra
streams increment.

However, the decrement operation is kept to prevent any omissions in
case of future evolutions of h2_init() error path. To prevent reporting
of a possible dead code, add an extra comment which summarizes the
situation.
---

diff --git a/src/mux_h2.c b/src/mux_h2.c
index 3708925a6..1c29cf5cc 100644
--- a/src/mux_h2.c
+++ b/src/mux_h2.c
@@ -1527,6 +1527,9 @@ static int h2_init(struct connection *conn, struct proxy *prx, struct session *s
 	TRACE_LEAVE(H2_EV_H2C_NEW, conn);
 	return 0;
   fail_stream:
+	/* Unnecessary code for now as fail_stream only occurs with BE conns.
+	 * Still better though to keep it to prevent future mistakes.
+	 */
 	if (!(h2c->flags & H2_CF_IS_BACK) && h2c->streams_hard_limit > 1)
 		_HA_ATOMIC_SUB(&tg_ctx->committed_extra_streams, h2c->streams_hard_limit - 1);
 	hpack_dht_free(h2c->ddht);