add soundio parameter to emit_rtprio_warning

closes #114

soundio/soundio.h

@@ -381,7 +381,7 @@ struct SoundIo {
     /// a message instructing the user how to configure their system to allow
     /// real-time priority threads. This must be set to a function not NULL.
     /// To silence the warning, assign this to a function that does nothing.
-    void (*emit_rtprio_warning)(void);
+    void (*emit_rtprio_warning)(struct SoundIo *);
 
     /// Optional: JACK info callback.
     /// By default, libsoundio sets this to an empty function in order to
@@ -389,6 +389,9 @@ struct SoundIo {
     /// setting this to `NULL` or providing your own function. This is
     /// registered with JACK regardless of whether ::soundio_connect_backend
     /// succeeds.
+    /// These functions are called globally from JACK and there is not a way
+    /// to provide access to the SoundIo instance. For more details, see
+    /// https://github.com/jackaudio/jack2/issues/235
     void (*jack_info_callback)(const char *msg);
     /// Optional: JACK error callback.
     /// See SoundIo::jack_info_callback

src/alsa.c

@@ -1447,7 +1447,7 @@ static enum SoundIoError outstream_start_alsa(struct SoundIoPrivate *si, struct
 
     enum SoundIoError err;
     SOUNDIO_ATOMIC_FLAG_TEST_AND_SET(osa->thread_exit_flag);
-    if ((err = soundio_os_thread_create(outstream_thread_run, os, soundio->emit_rtprio_warning, &osa->thread)))
+    if ((err = soundio_os_thread_create(outstream_thread_run, os, soundio, &osa->thread)))
         return err;
 
     return 0;
@@ -1749,7 +1749,7 @@ static enum SoundIoError instream_start_alsa(struct SoundIoPrivate *si, struct S
 
     SOUNDIO_ATOMIC_FLAG_TEST_AND_SET(isa->thread_exit_flag);
     enum SoundIoError err;
-    if ((err = soundio_os_thread_create(instream_thread_run, is, soundio->emit_rtprio_warning, &isa->thread))) {
+    if ((err = soundio_os_thread_create(instream_thread_run, is, soundio, &isa->thread))) {
         instream_destroy_alsa(si, is);
         return err;
     }

src/dummy.c

@@ -219,10 +219,8 @@ static enum SoundIoError outstream_start_dummy(struct SoundIoPrivate *si, struct
     struct SoundIo *soundio = &si->pub;
     assert(!osd->thread);
     SOUNDIO_ATOMIC_FLAG_TEST_AND_SET(osd->abort_flag);
-    int err;
+    enum SoundIoError err;
-    if ((err = soundio_os_thread_create(playback_thread_run, os,
+    if ((err = soundio_os_thread_create(playback_thread_run, os, soundio, &osd->thread))) {
-                    soundio->emit_rtprio_warning, &osd->thread)))
-    {
         return err;
     }
     return SoundIoErrorNone;
@@ -334,10 +332,8 @@ static enum SoundIoError instream_start_dummy(struct SoundIoPrivate *si, struct
     struct SoundIo *soundio = &si->pub;
     assert(!isd->thread);
     SOUNDIO_ATOMIC_FLAG_TEST_AND_SET(isd->abort_flag);
-    int err;
+    enum SoundIoError err;
-    if ((err = soundio_os_thread_create(capture_thread_run, is,
+    if ((err = soundio_os_thread_create(capture_thread_run, is, soundio, &isd->thread))) {
-                    soundio->emit_rtprio_warning, &isd->thread)))
-    {
         return err;
     }
     return 0;

src/os.c

@@ -186,7 +186,7 @@ static void *run_pthread(void *userdata) {
 
 int soundio_os_thread_create(
         void (*run)(void *arg), void *arg,
-        void (*emit_rtprio_warning)(void),
+        struct SoundIo *soundio,
         struct SoundIoOsThread **out_thread)
 {
     *out_thread = NULL;
@@ -206,9 +206,9 @@ int soundio_os_thread_create(
         soundio_os_thread_destroy(thread);
         return SoundIoErrorSystemResources;
     }
-    if (emit_rtprio_warning) {
+    if (soundio) {
         if (!SetThreadPriority(thread->handle, THREAD_PRIORITY_TIME_CRITICAL)) {
-            emit_rtprio_warning();
+            soundio->emit_rtprio_warning(soundio);
         }
     }
 #else
@@ -219,7 +219,7 @@ int soundio_os_thread_create(
     }
     thread->attr_init = true;
     
-    if (emit_rtprio_warning) {
+    if (soundio) {
         int max_priority = sched_get_priority_max(SCHED_FIFO);
         if (max_priority == -1) {
             soundio_os_thread_destroy(thread);
@@ -241,8 +241,8 @@ int soundio_os_thread_create(
     }
 
     if ((err = pthread_create(&thread->id, &thread->attr, run_pthread, thread))) {
-        if (err == EPERM && emit_rtprio_warning) {
+        if (err == EPERM && soundio) {
-            emit_rtprio_warning();
+            soundio->emit_rtprio_warning(soundio);
             err = pthread_create(&thread->id, NULL, run_pthread, thread);
         }
         if (err) {

src/os.h

@@ -19,9 +19,10 @@ int soundio_os_init(void);
 double soundio_os_get_time(void);
 
 struct SoundIoOsThread;
+struct SoundIo;
 int soundio_os_thread_create(
         void (*run)(void *arg), void *arg,
-        void (*emit_rtprio_warning)(void),
+        struct SoundIo *soundio, // pass NULL to disable real time priority
         struct SoundIoOsThread **out_thread);
 
 void soundio_os_thread_destroy(struct SoundIoOsThread *thread);

src/soundio.c

@@ -186,7 +186,7 @@ static void default_backend_disconnect_cb(struct SoundIo *soundio, enum SoundIoE
 }
 
 static struct SoundIoAtomicFlag rtprio_seen = SOUNDIO_ATOMIC_FLAG_INIT;
-static void default_emit_rtprio_warning(void) {
+static void default_emit_rtprio_warning(struct SoundIo *soundio) {
     if (!SOUNDIO_ATOMIC_FLAG_TEST_AND_SET(rtprio_seen)) {
         fprintf(stderr, "warning: unable to set high priority thread: Operation not permitted\n");
         fprintf(stderr, "See "