Increase refcount of the local chassis when a new port is created.

Also add an explanation of refcount handling in a part of the code
that was a bit difficult to follow. Now, each time that p_chassis is
affected to a new value, c_refcount should be updated accordingly.

diff --git a/src/lldpd.c b/src/lldpd.c
index d65d519f1b1d0fd674ccdf69377f21ac4392806b..6e7b974ef83f81fb8cea595c8396c5d93efc71d8 100644 (file)
--- a/src/lldpd.c
+++ b/src/lldpd.c
@@ -124,6 +124,7 @@ lldpd_alloc_hardware(struct lldpd *cfg, char *name)
 
        strlcpy(hardware->h_ifname, name, sizeof(hardware->h_ifname));
        hardware->h_lport.p_chassis = LOCAL_CHASSIS(cfg);
+       hardware->h_lport.p_chassis->c_refcount++;
        TAILQ_INIT(&hardware->h_rports);
 
 #ifdef ENABLE_LLDPMED
@@ -365,7 +366,6 @@ lldpd_decode(struct lldpd *cfg, char *frame, int s,
        } else {
                /* Chassis not known, add it */
                chassis->c_index = ++cfg->g_lastrid;
-               port->p_chassis = chassis;
                chassis->c_refcount = 0;
                TAILQ_INSERT_TAIL(&cfg->g_chassis, chassis, c_entries);
                i = 0; TAILQ_FOREACH(ochassis, &cfg->g_chassis, c_entries) i++;
@@ -381,6 +381,19 @@ lldpd_decode(struct lldpd *cfg, char *frame, int s,
        TAILQ_INSERT_TAIL(&hardware->h_rports, port, p_entries);
        port->p_chassis = chassis;
        port->p_chassis->c_refcount++;
+       /* Several cases are possible :
+            1. chassis is new, its refcount was 0. It is now attached
+               to this port, its refcount is 1.
+            2. chassis already exists and was attached to another
+               port, we increase its refcount accordingly.
+            3. chassis already exists and was attached to the same
+               port, its refcount was decreased with
+               lldpd_port_cleanup() and is now increased again.
+
+          In all cases, if the port already existed, it has been
+          freed with lldpd_port_cleanup() and therefore, the refcount
+          of the chassis that was attached to it is decreased.
+       */
        i = 0; TAILQ_FOREACH(oport, &hardware->h_rports, p_entries) i++;
        LLOG_DEBUG("Currently, %s known %d neighbors",
            hardware->h_ifname, i);