From: Willy Tarreau <w@1wt.eu>
Date: Tue, 18 Aug 2015 15:15:20 +0000 (+0200)
Subject: BUG/MEDIUM: counters: ensure that src_{inc,clr}_gpc0 creates a missing entry
X-Git-Tag: v1.6-dev4~65
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0f4eadd4830279f5ee83aa545728fb750f5c8185;p=thirdparty%2Fhaproxy.git

BUG/MEDIUM: counters: ensure that src_{inc,clr}_gpc0 creates a missing entry

During 1.5-dev20 there was some code refactoring to make the src_* fetch
function use the same code as sc_*. Unfortunately this introduced a
regression where src_* doesn't create an entry anymore if it does not
exist in the table. The reason is that smp_fetch_sc_stkctr() only calls
stktable_lookup_key() while src_inc_*/src_clr_* used to make use of
stktable_update_key() which additionally create the entry if it does
not exist.

There's no point modifying the common function for these two exceptions,
so instead we now have a function dedicated to the creation of this entry
for src_* only. It is called when the entry didn't exist, so that requires
minimal modifications to existing code.

Thanks to Thierry Fournier for helping diagnose the issue.

This fix must be backported to 1.5.
---

diff --git a/src/stream.c b/src/stream.c
index c745ecfc3e..82b07439aa 100644
--- a/src/stream.c
+++ b/src/stream.c
@@ -2636,6 +2636,33 @@ smp_fetch_sc_stkctr(struct session *sess, struct stream *strm, const struct arg
 	return stkptr;
 }
 
+/* same as smp_fetch_sc_stkctr() but dedicated to src_* and can create
+ * the entry if it doesn't exist yet. This is needed for a few fetch
+ * functions which need to create an entry, such as src_inc_gpc* and
+ * src_clr_gpc*.
+ */
+struct stkctr *
+smp_create_src_stkctr(struct session *sess, struct stream *strm, const struct arg *args, const char *kw)
+{
+	static struct stkctr stkctr;
+	struct stktable_key *key;
+	struct connection *conn = objt_conn(sess->origin);
+
+	if (strncmp(kw, "src_", 4) != 0)
+		return NULL;
+
+	if (!conn)
+		return NULL;
+
+	key = addr_to_stktable_key(&conn->addr.from, args->data.prx->table.type);
+	if (!key)
+		return NULL;
+
+	stkctr.table = &args->data.prx->table;
+	stkctr_set_entry(&stkctr, stktable_update_key(stkctr.table, key));
+	return &stkctr;
+}
+
 /* set return a boolean indicating if the requested stream counter is
  * currently being tracked or not.
  * Supports being called as "sc[0-9]_tracked" only.
@@ -2716,6 +2743,10 @@ smp_fetch_sc_inc_gpc0(const struct arg *args, struct sample *smp, const char *kw
 	smp->flags = SMP_F_VOL_TEST;
 	smp->type = SMP_T_SINT;
 	smp->data.sint = 0;
+
+	if (stkctr_entry(stkctr) == NULL)
+		stkctr = smp_create_src_stkctr(smp->sess, smp->strm, args, kw);
+
 	if (stkctr_entry(stkctr) != NULL) {
 		void *ptr1,*ptr2;
 
@@ -2755,6 +2786,10 @@ smp_fetch_sc_clr_gpc0(const struct arg *args, struct sample *smp, const char *kw
 	smp->flags = SMP_F_VOL_TEST;
 	smp->type = SMP_T_SINT;
 	smp->data.sint = 0;
+
+	if (stkctr_entry(stkctr) == NULL)
+		stkctr = smp_create_src_stkctr(smp->sess, smp->strm, args, kw);
+
 	if (stkctr_entry(stkctr) != NULL) {
 		void *ptr = stktable_data_ptr(stkctr->table, stkctr_entry(stkctr), STKTABLE_DT_GPC0);
 		if (!ptr)