sink-input/source-output: Don't crash when cork() is called without valid sink or source

If pa_sink_input_cork() or pa_source_output_cork() were called without a sink
or source attached, the calls would crash pulseaudio.

This patch fixes the problem, so that a source output or sink input can still
be corked or uncorked while source or sink are invalid. This is needed to
correct the corking logic in module-loopback.

src/modules/echo-cancel/module-echo-cancel.c

@@ -1322,12 +1322,11 @@ static void sink_input_detach_cb(pa_sink_input *i) {
     }
 }
 
-/* Called from source I/O thread context. */
+/* Called from source I/O thread context except when cork() is called without valid source. */
 static void source_output_state_change_cb(pa_source_output *o, pa_source_output_state_t state) {
     struct userdata *u;
 
     pa_source_output_assert_ref(o);
-    pa_source_output_assert_io_context(o);
     pa_assert_se(u = o->userdata);
 
     pa_log_debug("Source output %d state %d", o->index, state);
@@ -1345,7 +1344,7 @@ static void sink_input_state_change_cb(pa_sink_input *i, pa_sink_input_state_t s
     /* If we are added for the first time, ask for a rewinding so that
      * we are heard right-away. */
     if (PA_SINK_INPUT_IS_LINKED(state) &&
-        i->thread_info.state == PA_SINK_INPUT_INIT) {
+        i->thread_info.state == PA_SINK_INPUT_INIT && i->sink) {
         pa_log_debug("Requesting rewind due to state change.");
         pa_sink_input_request_rewind(i, 0, false, true, true);
     }

src/modules/module-equalizer-sink.c

@@ -860,7 +860,7 @@ static void sink_input_state_change_cb(pa_sink_input *i, pa_sink_input_state_t s
     /* If we are added for the first time, ask for a rewinding so that
      * we are heard right-away. */
     if (PA_SINK_INPUT_IS_LINKED(state) &&
-        i->thread_info.state == PA_SINK_INPUT_INIT) {
+        i->thread_info.state == PA_SINK_INPUT_INIT && i->sink) {
         pa_log_debug("Requesting rewind due to state change.");
         pa_sink_input_request_rewind(i, 0, false, true, true);
     }

src/modules/module-ladspa-sink.c

@@ -633,7 +633,7 @@ static void sink_input_state_change_cb(pa_sink_input *i, pa_sink_input_state_t s
     /* If we are added for the first time, ask for a rewinding so that
      * we are heard right-away. */
     if (PA_SINK_INPUT_IS_LINKED(state) &&
-            i->thread_info.state == PA_SINK_INPUT_INIT) {
+            i->thread_info.state == PA_SINK_INPUT_INIT && i->sink) {
         pa_log_debug("Requesting rewind due to state change.");
         pa_sink_input_request_rewind(i, 0, false, true, true);
     }

src/modules/module-loopback.c

@@ -496,15 +496,14 @@ static void source_output_detach_cb(pa_source_output *o) {
     }
 }
 
-/* Called from input thread context */
+/* Called from input thread context except when cork() is called without valid source. */
 static void source_output_state_change_cb(pa_source_output *o, pa_source_output_state_t state) {
     struct userdata *u;
 
     pa_source_output_assert_ref(o);
-    pa_source_output_assert_io_context(o);
     pa_assert_se(u = o->userdata);
 
-    if (PA_SOURCE_OUTPUT_IS_LINKED(state) && o->thread_info.state == PA_SOURCE_OUTPUT_INIT) {
+    if (PA_SOURCE_OUTPUT_IS_LINKED(state) && o->thread_info.state == PA_SOURCE_OUTPUT_INIT && o->source) {
 
         u->skip = pa_usec_to_bytes(PA_CLIP_SUB(pa_source_get_latency_within_thread(o->source),
                                                u->latency),

src/modules/module-remap-sink.c

@@ -283,7 +283,7 @@ static void sink_input_state_change_cb(pa_sink_input *i, pa_sink_input_state_t s
     /* If we are added for the first time, ask for a rewinding so that
      * we are heard right-away. */
     if (PA_SINK_INPUT_IS_LINKED(state) &&
-        i->thread_info.state == PA_SINK_INPUT_INIT) {
+        i->thread_info.state == PA_SINK_INPUT_INIT && i->sink) {
         pa_log_debug("Requesting rewind due to state change.");
         pa_sink_input_request_rewind(i, 0, false, true, true);
     }

src/modules/module-remap-source.c

@@ -222,12 +222,11 @@ static void source_output_kill_cb(pa_source_output *o) {
     pa_module_unload_request(u->module, true);
 }
 
-/* Called from output thread context */
+/* Called from output thread context except when cork() is called without valid source. */
 static void source_output_state_change_cb(pa_source_output *o, pa_source_output_state_t state) {
     struct userdata *u;
 
     pa_source_output_assert_ref(o);
-    pa_source_output_assert_io_context(o);
     pa_assert_se(u = o->userdata);
 
     pa_log_debug("Source output %d state %d.", o->index, state);

src/modules/module-sine.c

@@ -112,7 +112,7 @@ static void sink_input_state_change_cb(pa_sink_input *i, pa_sink_input_state_t s
     /* If we are added for the first time, ask for a rewinding so that
      * we are heard right-away. */
     if (PA_SINK_INPUT_IS_LINKED(state) &&
-        i->thread_info.state == PA_SINK_INPUT_INIT)
+        i->thread_info.state == PA_SINK_INPUT_INIT && i->sink)
         pa_sink_input_request_rewind(i, 0, false, true, true);
 }
 

src/modules/module-suspend-on-idle.c

@@ -284,7 +284,7 @@ static pa_hook_result_t sink_input_state_changed_hook_cb(pa_core *c, pa_sink_inp
     pa_assert(u);
 
     state = pa_sink_input_get_state(s);
-    if (state == PA_SINK_INPUT_RUNNING || state == PA_SINK_INPUT_DRAINED)
+    if ((state == PA_SINK_INPUT_RUNNING || state == PA_SINK_INPUT_DRAINED) && s->sink)
         if ((d = pa_hashmap_get(u->device_infos, s->sink)))
             resume(d);
 
@@ -296,7 +296,7 @@ static pa_hook_result_t source_output_state_changed_hook_cb(pa_core *c, pa_sourc
     pa_source_output_assert_ref(s);
     pa_assert(u);
 
-    if (pa_source_output_get_state(s) == PA_SOURCE_OUTPUT_RUNNING) {
+    if (pa_source_output_get_state(s) == PA_SOURCE_OUTPUT_RUNNING && s->source) {
         struct device_info *d;
 
         if (s->source->monitor_of)

src/modules/module-virtual-sink.c

@@ -409,7 +409,7 @@ static void sink_input_state_change_cb(pa_sink_input *i, pa_sink_input_state_t s
     /* If we are added for the first time, ask for a rewinding so that
      * we are heard right-away. */
     if (PA_SINK_INPUT_IS_LINKED(state) &&
-        i->thread_info.state == PA_SINK_INPUT_INIT) {
+        i->thread_info.state == PA_SINK_INPUT_INIT && i->sink) {
         pa_log_debug("Requesting rewind due to state change.");
         pa_sink_input_request_rewind(i, 0, false, true, true);
     }

src/modules/module-virtual-source.c

@@ -391,17 +391,16 @@ static void source_output_detach_cb(pa_source_output *o) {
     pa_source_set_rtpoll(u->source, NULL);
 }
 
-/* Called from output thread context */
+/* Called from output thread context except when cork() is called without valid source.*/
 static void source_output_state_change_cb(pa_source_output *o, pa_source_output_state_t state) {
     struct userdata *u;
 
     pa_source_output_assert_ref(o);
-    pa_source_output_assert_io_context(o);
     pa_assert_se(u = o->userdata);
 
     /* FIXME */
 #if 0
-    if (PA_SOURCE_OUTPUT_IS_LINKED(state) && o->thread_info.state == PA_SOURCE_OUTPUT_INIT) {
+    if (PA_SOURCE_OUTPUT_IS_LINKED(state) && o->thread_info.state == PA_SOURCE_OUTPUT_INIT && o->source) {
 
         u->skip = pa_usec_to_bytes(PA_CLIP_SUB(pa_source_get_latency_within_thread(o->source),
                                                u->latency),

src/modules/module-virtual-surround-sink.c

@@ -421,7 +421,7 @@ static void sink_input_state_change_cb(pa_sink_input *i, pa_sink_input_state_t s
     /* If we are added for the first time, ask for a rewinding so that
      * we are heard right-away. */
     if (PA_SINK_INPUT_IS_LINKED(state) &&
-        i->thread_info.state == PA_SINK_INPUT_INIT) {
+        i->thread_info.state == PA_SINK_INPUT_INIT && i->sink) {
         pa_log_debug("Requesting rewind due to state change.");
         pa_sink_input_request_rewind(i, 0, false, true, true);
     }