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Index: trunk/pjsip/include/pjsip/sip_transaction.h
===================================================================
--- a/pjsip/include/pjsip/sip_transaction.h (revision 5572)
+++ b/pjsip/include/pjsip/sip_transaction.h (revision 5573)
@@ -180,4 +180,8 @@
* is created by calling #pjsip_tsx_create_key() from an incoming message.
*
+ * IMPORTANT: To prevent deadlock, application should use
+ * #pjsip_tsx_layer_find_tsx2() instead which only adds a reference to
+ * the transaction instead of locking it.
+ *
* @param key The key string to find the transaction.
* @param lock If non-zero, transaction will be locked before the
@@ -190,4 +194,19 @@
PJ_DECL(pjsip_transaction*) pjsip_tsx_layer_find_tsx( const pj_str_t *key,
pj_bool_t lock );
+
+/**
+ * Find a transaction with the specified key. The transaction key normally
+ * is created by calling #pjsip_tsx_create_key() from an incoming message.
+ *
+ * @param key The key string to find the transaction.
+ * @param add_ref If non-zero, transaction's reference will be added
+ * by one before the function returns, to make sure that
+ * it's not deleted by other threads.
+ *
+ * @return The matching transaction instance, or NULL if transaction
+ * can not be found.
+ */
+PJ_DECL(pjsip_transaction*) pjsip_tsx_layer_find_tsx2( const pj_str_t *key,
+ pj_bool_t add_ref );
/**
Index: trunk/pjsip/src/pjsip/sip_transaction.c
===================================================================
--- a/pjsip/src/pjsip/sip_transaction.c (revision 5572)
+++ b/pjsip/src/pjsip/sip_transaction.c (revision 5573)
@@ -642,6 +642,6 @@
* Find a transaction.
*/
-PJ_DEF(pjsip_transaction*) pjsip_tsx_layer_find_tsx( const pj_str_t *key,
- pj_bool_t lock )
+static pjsip_transaction* find_tsx( const pj_str_t *key, pj_bool_t lock,
+ pj_bool_t add_ref )
{
pjsip_transaction *tsx;
@@ -655,5 +655,5 @@
/* Prevent the transaction to get deleted before we have chance to lock it.
*/
- if (tsx && lock)
+ if (tsx)
pj_grp_lock_add_ref(tsx->grp_lock);
@@ -667,10 +667,27 @@
PJ_RACE_ME(5);
- if (tsx && lock) {
- pj_grp_lock_acquire(tsx->grp_lock);
- pj_grp_lock_dec_ref(tsx->grp_lock);
+ if (tsx) {
+ if (lock)
+ pj_grp_lock_acquire(tsx->grp_lock);
+
+ if (!add_ref)
+ pj_grp_lock_dec_ref(tsx->grp_lock);
}
return tsx;
+}
+
+
+PJ_DEF(pjsip_transaction*) pjsip_tsx_layer_find_tsx( const pj_str_t *key,
+ pj_bool_t lock )
+{
+ return find_tsx(key, lock, PJ_FALSE);
+}
+
+
+PJ_DEF(pjsip_transaction*) pjsip_tsx_layer_find_tsx2( const pj_str_t *key,
+ pj_bool_t add_ref )
+{
+ return find_tsx(key, PJ_FALSE, add_ref);
}
Index: trunk/pjsip/src/pjsip/sip_ua_layer.c
===================================================================
--- a/pjsip/src/pjsip/sip_ua_layer.c (revision 5572)
+++ b/pjsip/src/pjsip/sip_ua_layer.c (revision 5573)
@@ -552,10 +552,10 @@
/* Lookup the INVITE transaction */
- tsx = pjsip_tsx_layer_find_tsx(&key, PJ_TRUE);
+ tsx = pjsip_tsx_layer_find_tsx2(&key, PJ_TRUE);
/* We should find the dialog attached to the INVITE transaction */
if (tsx) {
dlg = (pjsip_dialog*) tsx->mod_data[mod_ua.mod.id];
- pj_grp_lock_release(tsx->grp_lock);
+ pj_grp_lock_dec_ref(tsx->grp_lock);
/* Dlg may be NULL on some extreme condition
Index: trunk/pjsip/src/pjsip-ua/sip_inv.c
===================================================================
--- a/pjsip/src/pjsip-ua/sip_inv.c (revision 5572)
+++ b/pjsip/src/pjsip-ua/sip_inv.c (revision 5573)
@@ -3276,5 +3276,5 @@
pjsip_tsx_create_key(rdata->tp_info.pool, &key, PJSIP_ROLE_UAS,
pjsip_get_invite_method(), rdata);
- invite_tsx = pjsip_tsx_layer_find_tsx(&key, PJ_TRUE);
+ invite_tsx = pjsip_tsx_layer_find_tsx2(&key, PJ_TRUE);
if (invite_tsx == NULL) {
@@ -3325,5 +3325,5 @@
if (invite_tsx)
- pj_grp_lock_release(invite_tsx->grp_lock);
+ pj_grp_lock_dec_ref(invite_tsx->grp_lock);
}
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