res_stasis: Add control ref to playback and recording structs.

The stasis_app_playback and stasis_app_recording structs need to have a
struct stasis_app_control ref.  Other threads can get a reference to the
playback and recording structs from their respective global container.
These other threads can then use the control pointer they contain after
the control struct has gone.

* Add control ref to stasis_app_playback and stasis_app_recording structs.

With the refs added, the control command queue can now have a circular
control reference which will cause the control struct to never get
released if the control's command queue is not flushed when the channel
leaves the Stasis application.  Also the command queue needs better
protection from adding commands if the control->is_done flag is set.

* Flush the control command queue on exit.

ASTERISK-25882 #close

Change-Id: I3cf1fb59cbe6f50f20d9e35a2c07ac07d7f4320d

diff --git a/include/asterisk/stasis_app.h b/include/asterisk/stasis_app.h
index f2b07e0bfebb93eba2150023dc92cb49fd2780bc..90ef82ebf435ab0efb41cbcf417fe3783d76d7b5 100644 (file)
--- a/include/asterisk/stasis_app.h
+++ b/include/asterisk/stasis_app.h
@@ -439,6 +439,16 @@ void stasis_app_control_execute_until_exhausted(
 int stasis_app_control_is_done(
        struct stasis_app_control *control);
 
+/*!
+ * \brief Flush the control command queue.
+ * \since 13.9.0
+ *
+ * \param control Control object to flush command queue.
+ *
+ * \return Nothing
+ */
+void stasis_app_control_flush_queue(struct stasis_app_control *control);
+
 /*!
  * \brief Returns the uniqueid of the channel associated with this control
  *

diff --git a/res/ari/resource_bridges.c b/res/ari/resource_bridges.c
index ad37053f77633af9d42fb09a59ebbdd54646273b..7861f4a459af6dd22afdbcc438526cbaaa9a5daa 100644 (file)
--- a/res/ari/resource_bridges.c
+++ b/res/ari/resource_bridges.c
@@ -297,10 +297,11 @@ static void *bridge_channel_control_thread(void *data)
        thread_data = NULL;
 
        stasis_app_control_execute_until_exhausted(bridge_channel, control);
+       stasis_app_control_flush_queue(control);
 
-       ast_hangup(bridge_channel);
-       ao2_cleanup(control);
        stasis_forward_cancel(forward);
+       ao2_cleanup(control);
+       ast_hangup(bridge_channel);
        return NULL;
 }
 

diff --git a/res/res_stasis.c b/res/res_stasis.c
index cecc6ef2d78143e0766f895164fb6c6449ea3de9..4bb967dbffefe84afefcd4d15595718f376ae537 100644 (file)
--- a/res/res_stasis.c
+++ b/res/res_stasis.c
@@ -1179,6 +1179,11 @@ int stasis_app_control_is_done(struct stasis_app_control *control)
        return control_is_done(control);
 }
 
+void stasis_app_control_flush_queue(struct stasis_app_control *control)
+{
+       control_flush_queue(control);
+}
+
 struct ast_datastore_info set_end_published_info = {
        .type = "stasis_end_published",
 };
@@ -1371,6 +1376,8 @@ int stasis_app_exec(struct ast_channel *chan, const char *app_name, int argc,
                remove_stasis_end_published(chan);
        }
 
+       control_flush_queue(control);
+
        /* Stop any lingering silence generator */
        control_silence_stop_now(control);
 

diff --git a/res/res_stasis_playback.c b/res/res_stasis_playback.c
index 779dd77550698079323661200659690d2a880608..7fdb5d4ad7467ea0bf5acebdd00301ab74ed7ce2 100644 (file)
--- a/res/res_stasis_playback.c
+++ b/res/res_stasis_playback.c
@@ -118,6 +118,7 @@ static void playback_dtor(void *obj)
 {
        struct stasis_app_playback *playback = obj;
 
+       ao2_cleanup(playback->control);
        ast_string_field_free_memory(playback);
 }
 
@@ -143,6 +144,7 @@ static struct stasis_app_playback *playback_create(
                ast_string_field_set(playback, id, uuid);
        }
 
+       ao2_ref(control, +1);
        playback->control = control;
 
        ao2_ref(playback, +1);

diff --git a/res/res_stasis_recording.c b/res/res_stasis_recording.c
index 392d92c8e54056d50a62feb69427e55194804fd4..f907b7a0dbf3183f95992f4af3dc61f3354b41a4 100644 (file)
--- a/res/res_stasis_recording.c
+++ b/res/res_stasis_recording.c
@@ -358,6 +358,7 @@ static void recording_dtor(void *obj)
        struct stasis_app_recording *recording = obj;
 
        ast_free(recording->absolute_name);
+       ao2_cleanup(recording->control);
        ao2_cleanup(recording->options);
 }
 
@@ -413,6 +414,7 @@ struct stasis_app_recording *stasis_app_control_record(
 
        ao2_ref(options, +1);
        recording->options = options;
+       ao2_ref(control, +1);
        recording->control = control;
        recording->state = STASIS_APP_RECORDING_STATE_QUEUED;
 

diff --git a/res/stasis/control.c b/res/stasis/control.c
index 00385a09f1ef0d54e90e2814cfafc4d853783c1a..97b0b880909029da5fe7f486416df257f516847f 100644 (file)
--- a/res/stasis/control.c
+++ b/res/stasis/control.c
@@ -251,6 +251,11 @@ static struct stasis_app_command *exec_command_on_condition(
        }
 
        ao2_lock(control->command_queue);
+       if (control->is_done) {
+               ao2_unlock(control->command_queue);
+               ao2_ref(command, -1);
+               return NULL;
+       }
        if (can_exec_fn && (retval = can_exec_fn(control))) {
                ao2_unlock(control->command_queue);
                command_complete(command, retval);
@@ -402,7 +407,10 @@ int control_is_done(struct stasis_app_control *control)
 
 void control_mark_done(struct stasis_app_control *control)
 {
+       /* Locking necessary to sync with other threads adding commands to the queue. */
+       ao2_lock(control->command_queue);
        control->is_done = 1;
+       ao2_unlock(control->command_queue);
 }
 
 struct stasis_app_control_continue_data {
@@ -427,7 +435,7 @@ static int app_control_continue(struct stasis_app_control *control,
        /* Called from stasis_app_exec thread; no lock needed */
        ast_explicit_goto(control->channel, continue_data->context, continue_data->extension, continue_data->priority);
 
-       control->is_done = 1;
+       control_mark_done(control);
 
        return 0;
 }
@@ -1115,24 +1123,36 @@ int stasis_app_control_queue_control(struct stasis_app_control *control,
        return ast_queue_control(control->channel, frame_type);
 }
 
+void control_flush_queue(struct stasis_app_control *control)
+{
+       struct ao2_iterator iter;
+       struct stasis_app_command *command;
+
+       iter = ao2_iterator_init(control->command_queue, AO2_ITERATOR_UNLINK);
+       while ((command = ao2_iterator_next(&iter))) {
+               command_complete(command, -1);
+               ao2_ref(command, -1);
+       }
+       ao2_iterator_destroy(&iter);
+}
+
 int control_dispatch_all(struct stasis_app_control *control,
        struct ast_channel *chan)
 {
        int count = 0;
-       struct ao2_iterator i;
-       void *obj;
+       struct ao2_iterator iter;
+       struct stasis_app_command *command;
 
        ast_assert(control->channel == chan);
 
-       i = ao2_iterator_init(control->command_queue, AO2_ITERATOR_UNLINK);
-
-       while ((obj = ao2_iterator_next(&i))) {
-               RAII_VAR(struct stasis_app_command *, command, obj, ao2_cleanup);
+       iter = ao2_iterator_init(control->command_queue, AO2_ITERATOR_UNLINK);
+       while ((command = ao2_iterator_next(&iter))) {
                command_invoke(command, control, chan);
+               ao2_ref(command, -1);
                ++count;
        }
+       ao2_iterator_destroy(&iter);
 
-       ao2_iterator_destroy(&i);
        return count;
 }
 

diff --git a/res/stasis/control.h b/res/stasis/control.h
index d053a35f7c3aa98a44817841d841c43658833cda..1d37a494aec9f49fcef7deda13d5ff9dccfdb62e 100644 (file)
--- a/res/stasis/control.h
+++ b/res/stasis/control.h
@@ -40,6 +40,16 @@
  */
 struct stasis_app_control *control_create(struct ast_channel *channel, struct stasis_app *app);
 
+/*!
+ * \brief Flush the control command queue.
+ * \since 13.9.0
+ *
+ * \param control Control object to flush command queue.
+ *
+ * \return Nothing
+ */
+void control_flush_queue(struct stasis_app_control *control);
+
 /*!
  * \brief Dispatch all commands enqueued to this control.
  *