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PulseAudio: Hotplug support!

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icculus committed Mar 20, 2015
1 parent 11cffe1 commit cafd030ba691b50b0f707703acc3f28f1b71729b
Showing with 142 additions and 75 deletions.
  1. +140 −75 src/audio/pulseaudio/SDL_pulseaudio.c
  2. +2 −0 src/audio/pulseaudio/SDL_pulseaudio.h
@@ -72,6 +72,8 @@ static const char * (*PULSEAUDIO_pa_strerror) (int);
static pa_mainloop * (*PULSEAUDIO_pa_mainloop_new) (void);
static pa_mainloop_api * (*PULSEAUDIO_pa_mainloop_get_api) (pa_mainloop *);
static int (*PULSEAUDIO_pa_mainloop_iterate) (pa_mainloop *, int, int *);
static int (*PULSEAUDIO_pa_mainloop_run) (pa_mainloop *, int *);
static void (*PULSEAUDIO_pa_mainloop_quit) (pa_mainloop *, int);
static void (*PULSEAUDIO_pa_mainloop_free) (pa_mainloop *);

static pa_operation_state_t (*PULSEAUDIO_pa_operation_get_state) (
@@ -83,9 +85,13 @@ static pa_context * (*PULSEAUDIO_pa_context_new) (pa_mainloop_api *,
const char *);
static int (*PULSEAUDIO_pa_context_connect) (pa_context *, const char *,
pa_context_flags_t, const pa_spawn_api *);
static pa_operation * (*PULSEAUDIO_pa_context_get_sink_info_list)(pa_context *, pa_sink_info_cb_t, void *);
static pa_operation * (*PULSEAUDIO_pa_context_get_source_info_list)(pa_context *, pa_source_info_cb_t, void *);
static pa_operation * (*PULSEAUDIO_pa_context_get_sink_info_list) (pa_context *, pa_sink_info_cb_t, void *);
static pa_operation * (*PULSEAUDIO_pa_context_get_source_info_list) (pa_context *, pa_source_info_cb_t, void *);
static pa_operation * (*PULSEAUDIO_pa_context_get_sink_info_by_index) (pa_context *, uint32_t, pa_sink_info_cb_t, void *);
static pa_operation * (*PULSEAUDIO_pa_context_get_source_info_by_index) (pa_context *, uint32_t, pa_source_info_cb_t, void *);
static pa_context_state_t (*PULSEAUDIO_pa_context_get_state) (pa_context *);
static pa_operation * (*PULSEAUDIO_pa_context_subscribe) (pa_context *, pa_subscription_mask_t, pa_context_success_cb_t, void *);
static void (*PULSEAUDIO_pa_context_set_subscribe_callback) (pa_context *, pa_context_subscribe_cb_t, void *);
static void (*PULSEAUDIO_pa_context_disconnect) (pa_context *);
static void (*PULSEAUDIO_pa_context_unref) (pa_context *);

@@ -180,6 +186,8 @@ load_pulseaudio_syms(void)
SDL_PULSEAUDIO_SYM(pa_mainloop_new);
SDL_PULSEAUDIO_SYM(pa_mainloop_get_api);
SDL_PULSEAUDIO_SYM(pa_mainloop_iterate);
SDL_PULSEAUDIO_SYM(pa_mainloop_run);
SDL_PULSEAUDIO_SYM(pa_mainloop_quit);
SDL_PULSEAUDIO_SYM(pa_mainloop_free);
SDL_PULSEAUDIO_SYM(pa_operation_get_state);
SDL_PULSEAUDIO_SYM(pa_operation_cancel);
@@ -188,7 +196,11 @@ load_pulseaudio_syms(void)
SDL_PULSEAUDIO_SYM(pa_context_connect);
SDL_PULSEAUDIO_SYM(pa_context_get_sink_info_list);
SDL_PULSEAUDIO_SYM(pa_context_get_source_info_list);
SDL_PULSEAUDIO_SYM(pa_context_get_sink_info_by_index);
SDL_PULSEAUDIO_SYM(pa_context_get_source_info_by_index);
SDL_PULSEAUDIO_SYM(pa_context_get_state);
SDL_PULSEAUDIO_SYM(pa_context_subscribe);
SDL_PULSEAUDIO_SYM(pa_context_set_subscribe_callback);
SDL_PULSEAUDIO_SYM(pa_context_disconnect);
SDL_PULSEAUDIO_SYM(pa_context_unref);
SDL_PULSEAUDIO_SYM(pa_stream_new);
@@ -226,6 +238,19 @@ getAppName(void)
return "SDL Application"; /* oh well. */
}

static void
WaitForPulseOperation(pa_mainloop *mainloop, pa_operation *o)
{
/* This checks for NO errors currently. Either fix that, check results elsewhere, or do things you don't care about. */
if (mainloop && o) {
SDL_bool okay = SDL_TRUE;
while (okay && (PULSEAUDIO_pa_operation_get_state(o) == PA_OPERATION_RUNNING)) {
okay = (PULSEAUDIO_pa_mainloop_iterate(mainloop, 1, NULL) >= 0);
}
PULSEAUDIO_pa_operation_unref(o);
}
}

static void
DisconnectFromPulseServer(pa_mainloop *mainloop, pa_context *context)
{
@@ -300,7 +325,7 @@ PULSEAUDIO_WaitDevice(_THIS)
{
struct SDL_PrivateAudioData *h = this->hidden;

while(1) {
while (this->enabled) {
if (PULSEAUDIO_pa_context_get_state(h->context) != PA_CONTEXT_READY ||
PULSEAUDIO_pa_stream_get_state(h->stream) != PA_STREAM_READY ||
PULSEAUDIO_pa_mainloop_iterate(h->mainloop, 1, NULL) < 0) {
@@ -318,9 +343,10 @@ PULSEAUDIO_PlayDevice(_THIS)
{
/* Write the audio data */
struct SDL_PrivateAudioData *h = this->hidden;
if (PULSEAUDIO_pa_stream_write(h->stream, h->mixbuf, h->mixlen, NULL, 0LL,
PA_SEEK_RELATIVE) < 0) {
SDL_OpenedAudioDeviceDisconnected(this);
if (this->enabled) {
if (PULSEAUDIO_pa_stream_write(h->stream, h->mixbuf, h->mixlen, NULL, 0LL, PA_SEEK_RELATIVE) < 0) {
SDL_OpenedAudioDeviceDisconnected(this);
}
}
}

@@ -333,24 +359,21 @@ stream_drain_complete(pa_stream *s, int success, void *userdata)
static void
PULSEAUDIO_WaitDone(_THIS)
{
struct SDL_PrivateAudioData *h = this->hidden;
pa_operation *o;

o = PULSEAUDIO_pa_stream_drain(h->stream, stream_drain_complete, NULL);
if (!o) {
return;
}

while (PULSEAUDIO_pa_operation_get_state(o) != PA_OPERATION_DONE) {
if (PULSEAUDIO_pa_context_get_state(h->context) != PA_CONTEXT_READY ||
PULSEAUDIO_pa_stream_get_state(h->stream) != PA_STREAM_READY ||
PULSEAUDIO_pa_mainloop_iterate(h->mainloop, 1, NULL) < 0) {
PULSEAUDIO_pa_operation_cancel(o);
break;
if (this->enabled) {
struct SDL_PrivateAudioData *h = this->hidden;
pa_operation *o = PULSEAUDIO_pa_stream_drain(h->stream, stream_drain_complete, NULL);
if (o) {
while (PULSEAUDIO_pa_operation_get_state(o) != PA_OPERATION_DONE) {
if (PULSEAUDIO_pa_context_get_state(h->context) != PA_CONTEXT_READY ||
PULSEAUDIO_pa_stream_get_state(h->stream) != PA_STREAM_READY ||
PULSEAUDIO_pa_mainloop_iterate(h->mainloop, 1, NULL) < 0) {
PULSEAUDIO_pa_operation_cancel(o);
break;
}
}
PULSEAUDIO_pa_operation_unref(o);
}
}

PULSEAUDIO_pa_operation_unref(o);
}


@@ -367,22 +390,42 @@ PULSEAUDIO_CloseDevice(_THIS)
{
if (this->hidden != NULL) {
SDL_FreeAudioMem(this->hidden->mixbuf);
this->hidden->mixbuf = NULL;
SDL_free(this->hidden->device_name);
if (this->hidden->stream) {
PULSEAUDIO_pa_stream_disconnect(this->hidden->stream);
PULSEAUDIO_pa_stream_unref(this->hidden->stream);
this->hidden->stream = NULL;
}
DisconnectFromPulseServer(this->hidden->mainloop, this->hidden->context);
SDL_free(this->hidden);
this->hidden = NULL;
}
}

static void
DeviceNameCallback(pa_context *c, const pa_sink_info *i, int is_last, void *data)
{
if (i) {
char **devname = (char **) data;
*devname = SDL_strdup(i->name);
}
}

static SDL_bool
FindDeviceName(struct SDL_PrivateAudioData *h, void *handle)
{
const uint32_t idx = ((uint32_t) ((size_t) handle)) - 1;

if (handle == NULL) { /* NULL == default device. */
return SDL_TRUE;
}

WaitForPulseOperation(h->mainloop, PULSEAUDIO_pa_context_get_sink_info_by_index(h->context, idx, DeviceNameCallback, &h->device_name));
return (h->device_name != NULL);
}

static int
PULSEAUDIO_OpenDevice(_THIS, void *handle, const char *devname, int iscapture)
{
const char *devstr = (const char *) handle; /* NULL==default in Pulse. */
struct SDL_PrivateAudioData *h = NULL;
Uint16 test_format = 0;
pa_sample_spec paspec;
@@ -483,6 +526,11 @@ PULSEAUDIO_OpenDevice(_THIS, void *handle, const char *devname, int iscapture)
return SDL_SetError("Could not connect to PulseAudio server");
}

if (!FindDeviceName(h, handle)) {
PULSEAUDIO_CloseDevice(this);
return SDL_SetError("Requested PulseAudio sink missing?");
}

/* The SDL ALSA output hints us that we use Windows' channel mapping */
/* http://bugzilla.libsdl.org/show_bug.cgi?id=110 */
PULSEAUDIO_pa_channel_map_init_auto(&pacmap, this->spec.channels,
@@ -500,7 +548,13 @@ PULSEAUDIO_OpenDevice(_THIS, void *handle, const char *devname, int iscapture)
return SDL_SetError("Could not set up PulseAudio stream");
}

if (PULSEAUDIO_pa_stream_connect_playback(h->stream, devstr, &paattr, flags,
/* now that we have multi-device support, don't move a stream from
a device that was unplugged to something else, unless we're default. */
if (h->device_name != NULL) {
flags |= PA_STREAM_DONT_MOVE;
}

if (PULSEAUDIO_pa_stream_connect_playback(h->stream, h->device_name, &paattr, flags,
NULL, NULL) < 0) {
PULSEAUDIO_CloseDevice(this);
return SDL_SetError("Could not connect PulseAudio stream");
@@ -514,103 +568,115 @@ PULSEAUDIO_OpenDevice(_THIS, void *handle, const char *devname, int iscapture)
state = PULSEAUDIO_pa_stream_get_state(h->stream);
if (!PA_STREAM_IS_GOOD(state)) {
PULSEAUDIO_CloseDevice(this);
return SDL_SetError("Could not create to PulseAudio stream");
return SDL_SetError("Could not connect PulseAudio stream");
}
} while (state != PA_STREAM_READY);

/* We're ready to rock and roll. :-) */
return 0;
}

static pa_mainloop *hotplug_mainloop = NULL;
static pa_context *hotplug_context = NULL;
static SDL_Thread *hotplug_thread = NULL;

/* device handles are device index + 1, cast to void*, so we never pass a NULL. */

/* This is called when PulseAudio adds an output ("sink") device. */
static void
get_sinks_cb(pa_context *c, const pa_sink_info *i, int is_last, void *data)
SinkInfoCallback(pa_context *c, const pa_sink_info *i, int is_last, void *data)
{
SDL_bool *done = (SDL_bool *) data;

*done = (is_list != 0);
if (i) {
char *handle = SDL_strdup(i->name);
if (handle != NULL) {
SDL_AddAudioDevice(SDL_FALSE, i->description, handle);
}
SDL_AddAudioDevice(SDL_FALSE, i->description, (void *) ((size_t) i->index+1));
}
}

/* This is called when PulseAudio adds a capture ("source") device. */
static void
get_sources_cb(pa_context *c, const pa_sink_info *i, int is_last, void *data)
SourceInfoCallback(pa_context *c, const pa_source_info *i, int is_last, void *data)
{
SDL_bool *done = (SDL_bool *) data;

*done = (is_list != 0);
if (i) {
char *handle = SDL_strdup(i->name);
if (handle != NULL) {
SDL_AddAudioDevice(SDL_TRUE, i->description, handle);
/* Skip "monitor" sources. These are just output from other sinks. */
if (i->monitor_of_sink == PA_INVALID_INDEX) {
SDL_AddAudioDevice(SDL_TRUE, i->description, (void *) ((size_t) i->index+1));
}
}
}

/* This is called when PulseAudio has a device connected/removed/changed. */
static void
RunPulseDetectCallback(pa_mainloop *mainloop, pa_operation *o, SDL_bool *done)
HotplugCallback(pa_context *c, pa_subscription_event_type_t t, uint32_t idx, void *data)
{
do {
if (PULSEAUDIO_pa_operation_get_state(o) == PA_OPERATION_CANCELLED) {
break;
} else if (PULSEAUDIO_pa_mainloop_iterate(mainloop, 1, NULL) < 0) {
break;
const SDL_bool added = ((t & PA_SUBSCRIPTION_EVENT_TYPE_MASK) == PA_SUBSCRIPTION_EVENT_NEW);
const SDL_bool removed = ((t & PA_SUBSCRIPTION_EVENT_TYPE_MASK) == PA_SUBSCRIPTION_EVENT_REMOVE);

if (added || removed) { /* we only care about add/remove events. */
const SDL_bool sink = ((t & PA_SUBSCRIPTION_EVENT_FACILITY_MASK) == PA_SUBSCRIPTION_EVENT_SINK);
const SDL_bool source = ((t & PA_SUBSCRIPTION_EVENT_FACILITY_MASK) == PA_SUBSCRIPTION_EVENT_SOURCE);

/* adds need sink details from the PulseAudio server. Another callback... */
if (added && sink) {
PULSEAUDIO_pa_context_get_sink_info_by_index(hotplug_context, idx, SinkInfoCallback, NULL);
} else if (added && source) {
PULSEAUDIO_pa_context_get_source_info_by_index(hotplug_context, idx, SourceInfoCallback, NULL);
} else if (removed && (sink || source)) {
/* removes we can handle just with the device index. */
SDL_RemoveAudioDevice(source != 0, (void *) ((size_t) idx+1));
}
} while (*done == SDL_FALSE);
}
}

static void
PULSEAUDIO_DetectDevices()
/* this runs as a thread while the Pulse target is initialized to catch hotplug events. */
static int SDLCALL
HotplugThread(void *data)
{
pa_mainloop *mainloop = NULL;
pa_context *context = NULL;
pa_operation *o = NULL;
SDL_bool done;

if (ConnectToPulseServer(&mainloop, &context) < 0) {
return;
}

done = SDL_FALSE;
RunPulseDetectCallback(mainloop, PULSEAUDIO_pa_context_get_sink_info_list(context, get_sinks_cb, &done), &done);
done = SDL_FALSE;
RunPulseDetectCallback(mainloop, PULSEAUDIO_pa_context_get_source_info_list(context, get_sources_cb, &done), &done);

DisconnectFromPulseServer(mainloop, context);
pa_operation *o;
SDL_SetThreadPriority(SDL_THREAD_PRIORITY_LOW);
PULSEAUDIO_pa_context_set_subscribe_callback(hotplug_context, HotplugCallback, NULL);
o = PULSEAUDIO_pa_context_subscribe(hotplug_context, PA_SUBSCRIPTION_MASK_SINK | PA_SUBSCRIPTION_MASK_SOURCE, NULL, NULL);
PULSEAUDIO_pa_operation_unref(o); /* don't wait for it, just do our thing. */
PULSEAUDIO_pa_mainloop_run(hotplug_mainloop, NULL);
return 0;
}

static void
PULSEAUDIO_FreeDeviceHandle(void *handle)
PULSEAUDIO_DetectDevices()
{
SDL_free(handle); /* just a string we copied. */
WaitForPulseOperation(hotplug_mainloop, PULSEAUDIO_pa_context_get_sink_info_list(hotplug_context, SinkInfoCallback, NULL));
WaitForPulseOperation(hotplug_mainloop, PULSEAUDIO_pa_context_get_source_info_list(hotplug_context, SourceInfoCallback, NULL));

/* ok, we have a sane list, let's set up hotplug notifications now... */
hotplug_thread = SDL_CreateThread(HotplugThread, "PulseHotplug", NULL);
}

static void
PULSEAUDIO_Deinitialize(void)
{
if (hotplug_thread) {
PULSEAUDIO_pa_mainloop_quit(hotplug_mainloop, 0);
SDL_WaitThread(hotplug_thread, NULL);
hotplug_thread = NULL;
}

DisconnectFromPulseServer(hotplug_mainloop, hotplug_context);
hotplug_mainloop = NULL;
hotplug_context = NULL;

UnloadPulseAudioLibrary();
}

static int
PULSEAUDIO_Init(SDL_AudioDriverImpl * impl)
{
pa_mainloop *mainloop = NULL;
pa_context *context = NULL;

if (LoadPulseAudioLibrary() < 0) {
return 0;
}

if (ConnectToPulseServer(&mainloop, &context) < 0) {
if (ConnectToPulseServer(&hotplug_mainloop, &hotplug_context) < 0) {
UnloadPulseAudioLibrary();
return 0;
}

DisconnectFromPulseServer(mainloop, context);

/* Set the function pointers */
impl->DetectDevices = PULSEAUDIO_DetectDevices;
impl->OpenDevice = PULSEAUDIO_OpenDevice;
@@ -619,7 +685,6 @@ PULSEAUDIO_Init(SDL_AudioDriverImpl * impl)
impl->GetDeviceBuf = PULSEAUDIO_GetDeviceBuf;
impl->CloseDevice = PULSEAUDIO_CloseDevice;
impl->WaitDone = PULSEAUDIO_WaitDone;
impl->FreeDeviceHandle = PULSEAUDIO_FreeDeviceHandle;
impl->Deinitialize = PULSEAUDIO_Deinitialize;

return 1; /* this audio target is available. */
@@ -32,6 +32,8 @@

struct SDL_PrivateAudioData
{
char *device_name;

/* pulseaudio structures */
pa_mainloop *mainloop;
pa_context *context;

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