Merge slepp's sub-second expiration timer although hopefully it will never have to...

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@2872 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index e288bdcecd9baf7cf9ae4d39485797564a4baef9..e39ceae95e763eab1ad5236820cb1323ec2146c3 100755 (executable)
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -71,10 +71,12 @@
 #define DEFAULT_MAX_EXPIRY      3600
 
 /* guard limit must be larger than guard secs */
-/* guard min must be > 1 */
+/* guard min must be < 1000, and should be >= 250 */
 #define EXPIRY_GUARD_SECS      15      /* How long before expiry do we reregister */
 #define EXPIRY_GUARD_LIMIT      30     /* Below here, we use EXPIRY_GUARD_PCT instead of EXPIRY_GUARD_SECS */
-#define EXPIRY_GUARD_MIN        3      /* Below here, we use expires=1 instead of EXPIRY_GUARD_PCT * expires */
+#define EXPIRY_GUARD_MIN       500     /* This is the minimum guard time applied. If GUARD_PCT turns out
+                                       to be lower than this, it will use this time instead. This is in
+                                       milliseconds. */
 #define EXPIRY_GUARD_PCT        0.20   /* Percentage of expires timeout to use when below EXPIRY_GUARD_LIMIT */
 
 #ifndef MAX
@@ -5333,7 +5335,7 @@ static void handle_response(struct sip_pvt *p, int resp, char *rest, struct sip_
                                }
                        } else if (!strcasecmp(msg, "REGISTER")) {
                                /* char *exp; */
-                               int expires;
+                               int expires, expires_ms;
                                struct sip_registry *r;
                                r=p->registry;
                                if (r) {
@@ -5375,14 +5377,14 @@ static void handle_response(struct sip_pvt *p, int resp, char *rest, struct sip_
                                        }
                                        if (!expires) expires=atoi(get_header(req, "expires"));
                                        if (!expires) expires=default_expiry;
-                                       if (expires <= EXPIRY_GUARD_MIN)
-                                               expires = 1;
+
+                                       expires_ms = expires * 1000;
+                                       if (expires <= EXPIRY_GUARD_LIMIT)
+                                               expires_ms -= MAX((expires_ms * EXPIRY_GUARD_PCT),EXPIRY_GUARD_MIN);
                                        else
-                                               if (expires <= EXPIRY_GUARD_LIMIT)
-                                                       expires -= MAX((expires * EXPIRY_GUARD_PCT),(EXPIRY_GUARD_MIN - 1));
-                                               else
-                                                       expires -= EXPIRY_GUARD_SECS;
-                                       r->expire=ast_sched_add(sched, expires*1000, sip_reregister, r); 
+                                               expires_ms -= EXPIRY_GUARD_SECS * 1000;
+
+                                       r->expire=ast_sched_add(sched, expires_ms, sip_reregister, r); 
                                } else
                                        ast_log(LOG_WARNING, "Got 200 OK on REGISTER that isn't a register\n");