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pulseaudio: Implemented audio capture support!

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icculus committed Aug 2, 2016
1 parent 0d0f708 commit d662bc04a53ab77ee0742025bc2543aef0e32305
Showing with 130 additions and 20 deletions.
  1. +127 −20 src/audio/pulseaudio/SDL_pulseaudio.c
  2. +3 −0 src/audio/pulseaudio/SDL_pulseaudio.h
@@ -100,12 +100,19 @@ static pa_stream * (*PULSEAUDIO_pa_stream_new) (pa_context *, const char *,
const pa_sample_spec *, const pa_channel_map *);
static int (*PULSEAUDIO_pa_stream_connect_playback) (pa_stream *, const char *,
const pa_buffer_attr *, pa_stream_flags_t, pa_cvolume *, pa_stream *);
static int (*PULSEAUDIO_pa_stream_connect_record) (pa_stream *, const char *,
const pa_buffer_attr *, pa_stream_flags_t);
static pa_stream_state_t (*PULSEAUDIO_pa_stream_get_state) (pa_stream *);
static size_t (*PULSEAUDIO_pa_stream_writable_size) (pa_stream *);
static size_t (*PULSEAUDIO_pa_stream_readable_size) (pa_stream *);
static int (*PULSEAUDIO_pa_stream_write) (pa_stream *, const void *, size_t,
pa_free_cb_t, int64_t, pa_seek_mode_t);
static pa_operation * (*PULSEAUDIO_pa_stream_drain) (pa_stream *,
pa_stream_success_cb_t, void *);
static int (*PULSEAUDIO_pa_stream_peek) (pa_stream *, const void **, size_t *);
static int (*PULSEAUDIO_pa_stream_drop) (pa_stream *);
static pa_operation * (*PULSEAUDIO_pa_stream_flush) (pa_stream *,
pa_stream_success_cb_t, void *);
static int (*PULSEAUDIO_pa_stream_disconnect) (pa_stream *);
static void (*PULSEAUDIO_pa_stream_unref) (pa_stream *);

@@ -206,11 +213,16 @@ load_pulseaudio_syms(void)
SDL_PULSEAUDIO_SYM(pa_context_unref);
SDL_PULSEAUDIO_SYM(pa_stream_new);
SDL_PULSEAUDIO_SYM(pa_stream_connect_playback);
SDL_PULSEAUDIO_SYM(pa_stream_connect_record);
SDL_PULSEAUDIO_SYM(pa_stream_get_state);
SDL_PULSEAUDIO_SYM(pa_stream_writable_size);
SDL_PULSEAUDIO_SYM(pa_stream_readable_size);
SDL_PULSEAUDIO_SYM(pa_stream_write);
SDL_PULSEAUDIO_SYM(pa_stream_drain);
SDL_PULSEAUDIO_SYM(pa_stream_disconnect);
SDL_PULSEAUDIO_SYM(pa_stream_peek);
SDL_PULSEAUDIO_SYM(pa_stream_drop);
SDL_PULSEAUDIO_SYM(pa_stream_flush);
SDL_PULSEAUDIO_SYM(pa_stream_unref);
SDL_PULSEAUDIO_SYM(pa_channel_map_init_auto);
SDL_PULSEAUDIO_SYM(pa_strerror);
@@ -239,6 +251,12 @@ getAppName(void)
return "SDL Application"; /* oh well. */
}

static void
stream_operation_complete_no_op(pa_stream *s, int success, void *userdata)
{
/* no-op for pa_stream_drain(), etc, to use for callback. */
}

static void
WaitForPulseOperation(pa_mainloop *mainloop, pa_operation *o)
{
@@ -351,18 +369,12 @@ PULSEAUDIO_PlayDevice(_THIS)
}
}

static void
stream_drain_complete(pa_stream *s, int success, void *userdata)
{
/* no-op for pa_stream_drain() to use for callback. */
}

static void
PULSEAUDIO_WaitDone(_THIS)
{
if (SDL_AtomicGet(&this->enabled)) {
struct SDL_PrivateAudioData *h = this->hidden;
pa_operation *o = PULSEAUDIO_pa_stream_drain(h->stream, stream_drain_complete, NULL);
pa_operation *o = PULSEAUDIO_pa_stream_drain(h->stream, stream_operation_complete_no_op, NULL);
if (o) {
while (PULSEAUDIO_pa_operation_get_state(o) != PA_OPERATION_DONE) {
if (PULSEAUDIO_pa_context_get_state(h->context) != PA_CONTEXT_READY ||
@@ -386,10 +398,75 @@ PULSEAUDIO_GetDeviceBuf(_THIS)
}


static int
PULSEAUDIO_CaptureFromDevice(_THIS, void *buffer, int buflen)
{
struct SDL_PrivateAudioData *h = this->hidden;
const void *data = NULL;
size_t nbytes = 0;

while (SDL_AtomicGet(&this->enabled)) {
if (h->capturebuf != NULL) {
const int cpy = SDL_min(buflen, h->capturelen);
SDL_memcpy(buffer, h->capturebuf, cpy);
/*printf("PULSEAUDIO: fed %d captured bytes\n", cpy);*/
h->capturebuf += cpy;
h->capturelen -= cpy;
if (h->capturelen == 0) {
h->capturebuf = NULL;
PULSEAUDIO_pa_stream_drop(h->stream); /* done with this fragment. */
}
return cpy; /* new data, return it. */
}

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) {
SDL_OpenedAudioDeviceDisconnected(this);
return -1; /* uhoh, pulse failed! */
}

if (PULSEAUDIO_pa_stream_readable_size(h->stream) == 0) {
continue; /* no data available yet. */
}

/* a new fragment is available! */
PULSEAUDIO_pa_stream_peek(h->stream, &data, &nbytes);
SDL_assert(nbytes > 0);
if (data == NULL) { /* NULL==buffer had a hole. Ignore that. */
PULSEAUDIO_pa_stream_drop(h->stream); /* drop this fragment. */
} else {
/* store this fragment's data, start feeding it to SDL. */
/*printf("PULSEAUDIO: captured %d new bytes\n", (int) nbytes);*/
h->capturebuf = (const Uint8 *) data;
h->capturelen = nbytes;
}
}

return -1; /* not enabled? */
}

static void
PULSEAUDIO_FlushCapture(_THIS)
{
struct SDL_PrivateAudioData *h = this->hidden;

if (h->capturebuf != NULL) {
PULSEAUDIO_pa_stream_drop(h->stream);
h->capturebuf = NULL;
h->capturelen = 0;
}

WaitForPulseOperation(h->mainloop, PULSEAUDIO_pa_stream_flush(h->stream, stream_operation_complete_no_op, NULL));
}

static void
PULSEAUDIO_CloseDevice(_THIS)
{
if (this->hidden != NULL) {
if (this->hidden->capturebuf != NULL) {
PULSEAUDIO_pa_stream_drop(this->hidden->stream);
}
SDL_FreeAudioMem(this->hidden->mixbuf);
SDL_free(this->hidden->device_name);
if (this->hidden->stream) {
@@ -403,7 +480,16 @@ PULSEAUDIO_CloseDevice(_THIS)
}

static void
DeviceNameCallback(pa_context *c, const pa_sink_info *i, int is_last, void *data)
SinkDeviceNameCallback(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 void
SourceDeviceNameCallback(pa_context *c, const pa_source_info *i, int is_last, void *data)
{
if (i) {
char **devname = (char **) data;
@@ -412,15 +498,24 @@ DeviceNameCallback(pa_context *c, const pa_sink_info *i, int is_last, void *data
}

static SDL_bool
FindDeviceName(struct SDL_PrivateAudioData *h, void *handle)
FindDeviceName(struct SDL_PrivateAudioData *h, const int iscapture, 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));
if (iscapture) {
WaitForPulseOperation(h->mainloop,
PULSEAUDIO_pa_context_get_source_info_by_index(h->context, idx,
SourceDeviceNameCallback, &h->device_name));
} else {
WaitForPulseOperation(h->mainloop,
PULSEAUDIO_pa_context_get_sink_info_by_index(h->context, idx,
SinkDeviceNameCallback, &h->device_name));
}

return (h->device_name != NULL);
}

@@ -434,6 +529,7 @@ PULSEAUDIO_OpenDevice(_THIS, void *handle, const char *devname, int iscapture)
pa_channel_map pacmap;
pa_stream_flags_t flags = 0;
int state = 0;
int rc = 0;

/* Initialize all variables that we clean on shutdown */
this->hidden = (struct SDL_PrivateAudioData *)
@@ -495,13 +591,15 @@ PULSEAUDIO_OpenDevice(_THIS, void *handle, const char *devname, int iscapture)
SDL_CalculateAudioSpec(&this->spec);

/* Allocate mixing buffer */
h->mixlen = this->spec.size;
h->mixbuf = (Uint8 *) SDL_AllocAudioMem(h->mixlen);
if (h->mixbuf == NULL) {
PULSEAUDIO_CloseDevice(this);
return SDL_OutOfMemory();
if (!iscapture) {
h->mixlen = this->spec.size;
h->mixbuf = (Uint8 *) SDL_AllocAudioMem(h->mixlen);
if (h->mixbuf == NULL) {
PULSEAUDIO_CloseDevice(this);
return SDL_OutOfMemory();
}
SDL_memset(h->mixbuf, this->spec.silence, this->spec.size);
}
SDL_memset(h->mixbuf, this->spec.silence, this->spec.size);

paspec.channels = this->spec.channels;
paspec.rate = this->spec.freq;
@@ -527,9 +625,9 @@ PULSEAUDIO_OpenDevice(_THIS, void *handle, const char *devname, int iscapture)
return SDL_SetError("Could not connect to PulseAudio server");
}

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

/* The SDL ALSA output hints us that we use Windows' channel mapping */
@@ -555,8 +653,13 @@ PULSEAUDIO_OpenDevice(_THIS, void *handle, const char *devname, int iscapture)
flags |= PA_STREAM_DONT_MOVE;
}

if (PULSEAUDIO_pa_stream_connect_playback(h->stream, h->device_name, &paattr, flags,
NULL, NULL) < 0) {
if (iscapture) {
rc = PULSEAUDIO_pa_stream_connect_record(h->stream, h->device_name, &paattr, flags);
} else {
rc = PULSEAUDIO_pa_stream_connect_playback(h->stream, h->device_name, &paattr, flags, NULL, NULL);
}

if (rc < 0) {
PULSEAUDIO_CloseDevice(this);
return SDL_SetError("Could not connect PulseAudio stream");
}
@@ -687,6 +790,10 @@ PULSEAUDIO_Init(SDL_AudioDriverImpl * impl)
impl->CloseDevice = PULSEAUDIO_CloseDevice;
impl->WaitDone = PULSEAUDIO_WaitDone;
impl->Deinitialize = PULSEAUDIO_Deinitialize;
impl->CaptureFromDevice = PULSEAUDIO_CaptureFromDevice;
impl->FlushCapture = PULSEAUDIO_FlushCapture;

impl->HasCaptureSupport = SDL_TRUE;

return 1; /* this audio target is available. */
}
@@ -42,6 +42,9 @@ struct SDL_PrivateAudioData
/* Raw mixing buffer */
Uint8 *mixbuf;
int mixlen;

const Uint8 *capturebuf;
int capturelen;
};

#endif /* _SDL_pulseaudio_h */

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