Changeset 797 for pjproject/trunk/pjsip/src/pjsip/sip_ua_layer.c

Timestamp:

Nov 11, 2006 4:16:04 PM (17 years ago)

Author:

bennylp

Message:

Attended call transfer implementation. The changes involves:

• Added support for SIP Replaces extension (RFC 3891)
• Added pjsua_call_xfer_replaces() to perform attended call transfer.
• PJSUA checks and process Replaces header in incoming calls
• Added pjsip_ua_find_dialog() API.
• Added pjsip_endpt_has_capability() API.
• Added pjsip_endpt_send_response2() API.
• etc.

File:

• pjproject/trunk/pjsip/src/pjsip/sip_ua_layer.c (modified) (1 diff)

pjproject/trunk/pjsip/src/pjsip/sip_ua_layer.c

@@ -410 +410 @@
 
 
+/* 
+ * Find a dialog.
+ */
+PJ_DEF(pjsip_dialog*) pjsip_ua_find_dialog(const pj_str_t *call_id,
+                                           const pj_str_t *local_tag,
+                                           const pj_str_t *remote_tag,
+                                           pj_bool_t lock_dialog)
+{
+    struct dlg_set *dlg_set;
+    pjsip_dialog *dlg;
+
+    PJ_ASSERT_RETURN(call_id && local_tag && remote_tag, NULL);
+
+    /* Lock user agent. */
+    pj_mutex_lock(mod_ua.mutex);
+
+    /* Lookup the dialog set. */
+    dlg_set = pj_hash_get(mod_ua.dlg_table, local_tag->ptr, local_tag->slen,
+                          NULL);
+    if (dlg_set == NULL) {
+        /* Not found */
+        pj_mutex_unlock(mod_ua.mutex);
+        return NULL;
+    }
+
+    /* Dialog set is found, now find the matching dialog based on the
+     * remote tag.
+     */
+    dlg = dlg_set->dlg_list.next;
+    while (dlg != (pjsip_dialog*)&dlg_set->dlg_list) {  
+        if (pj_strcmp(&dlg->remote.info->tag, remote_tag) == 0)
+            break;
+        dlg = dlg->next;
+    }
+
+    if (dlg == (pjsip_dialog*)&dlg_set->dlg_list) {
+        /* Not found */
+        pj_mutex_unlock(mod_ua.mutex);
+        return NULL;
+    }
+
+    /* Dialog has been found. It SHOULD have the right Call-ID!! */
+    PJ_ASSERT_ON_FAIL(pj_strcmp(&dlg->call_id->id, call_id)==0, 
+                        {pj_mutex_unlock(mod_ua.mutex); return NULL;});
+
+    if (lock_dialog) {
+        if (pjsip_dlg_try_inc_lock(dlg) != PJ_SUCCESS) {
+
+            /*
+             * Unable to acquire dialog's lock while holding the user
+             * agent's mutex. Release the UA mutex before retrying once
+             * more.
+             *
+             * THIS MAY CAUSE RACE CONDITION!
+             */
+
+            /* Unlock user agent. */
+            pj_mutex_unlock(mod_ua.mutex);
+            /* Lock dialog */
+            pjsip_dlg_inc_lock(dlg);
+
+        } else {
+            /* Unlock user agent. */
+            pj_mutex_unlock(mod_ua.mutex);
+        }
+
+    } else {
+        /* Unlock user agent. */
+        pj_mutex_unlock(mod_ua.mutex);
+    }
+
+    return dlg;
+}
+
+
 /*
  * Find the first dialog in dialog set in hash table for an incoming message.