Store the number of periods in the device instead of the buffer size

Also keep all the fields in sync

Alc/ALc.c

@@ -614,7 +614,8 @@ ALCAPI ALCdevice* ALCAPIENTRY alcCaptureOpenDevice(const ALCchar *deviceName, AL
 
         pDevice->Frequency = frequency;
         pDevice->Format = format;
-        pDevice->BufferSize = SampleSize;
+        pDevice->UpdateSize = SampleSize;
+        pDevice->NumUpdates = 1;
 
         SuspendContext(NULL);
         for(i = 0;BackendList[i].Init;i++)
@@ -1481,9 +1482,16 @@ ALCAPI ALCdevice* ALCAPIENTRY alcOpenDevice(const ALCchar *deviceName)
         fmt = GetConfigValue(NULL, "format", "AL_FORMAT_STEREO16");
         device->Format = GetFormatFromString(fmt);
 
-        device->BufferSize = GetConfigValueInt(NULL, "refresh", 4096);
+        device->NumUpdates = GetConfigValueInt(NULL, "periods", 4);
-        if((ALint)device->BufferSize <= 0)
+        if(device->NumUpdates < 2)
-            device->BufferSize = 4096;
+            device->NumUpdates = 4;
+
+        i = GetConfigValueInt(NULL, "refresh", 4096);
+        if(i <= 0) i = 4096;
+
+        device->UpdateSize = GetConfigValueInt(NULL, "period_size", i/device->NumUpdates);
+        if(device->UpdateSize <= 0)
+            device->UpdateSize = i/device->NumUpdates;
 
         device->MaxNoOfSources = GetConfigValueInt(NULL, "sources", 256);
         if((ALint)device->MaxNoOfSources <= 0)

Alc/alsa.c

@@ -69,10 +69,12 @@ MAKE_FUNC(snd_pcm_hw_params_set_periods_near);
 MAKE_FUNC(snd_pcm_hw_params_set_rate_near);
 MAKE_FUNC(snd_pcm_hw_params_set_rate);
 MAKE_FUNC(snd_pcm_hw_params_set_buffer_size_near);
+MAKE_FUNC(snd_pcm_hw_params_set_period_size_near);
 MAKE_FUNC(snd_pcm_hw_params_set_buffer_size_min);
 MAKE_FUNC(snd_pcm_hw_params_get_buffer_size);
 MAKE_FUNC(snd_pcm_hw_params_get_period_size);
 MAKE_FUNC(snd_pcm_hw_params_get_access);
+MAKE_FUNC(snd_pcm_hw_params_get_periods);
 MAKE_FUNC(snd_pcm_hw_params);
 MAKE_FUNC(snd_pcm_sw_params_malloc);
 MAKE_FUNC(snd_pcm_sw_params_current);
@@ -411,7 +413,7 @@ static void alsa_close_playback(ALCdevice *device)
 static ALCboolean alsa_reset_playback(ALCdevice *device)
 {
     alsa_data *data = (alsa_data*)device->ExtraData;
-    snd_pcm_uframes_t bufferSizeInFrames;
+    snd_pcm_uframes_t periodSizeInFrames;
     snd_pcm_sw_params_t *sp = NULL;
     snd_pcm_hw_params_t *p = NULL;
     snd_pcm_access_t access;
@@ -439,8 +441,8 @@ static ALCboolean alsa_reset_playback(ALCdevice *device)
     }
 
     allowmmap = GetConfigValueBool("alsa", "mmap", 1);
-    periods = GetConfigValueInt("alsa", "periods", 0);
+    periods = GetConfigValueInt("alsa", "periods", device->NumUpdates);
-    bufferSizeInFrames = device->BufferSize;
+    periodSizeInFrames = device->UpdateSize;
     rate = device->Frequency;
 
     err = NULL;
@@ -451,6 +453,7 @@ static ALCboolean alsa_reset_playback(ALCdevice *device)
     /* set interleaved access */
     if(err == NULL && (!allowmmap || (i=psnd_pcm_hw_params_set_access(data->pcmHandle, p, SND_PCM_ACCESS_MMAP_INTERLEAVED)) < 0))
     {
+        if(periods > 2) periods--;
         if((i=psnd_pcm_hw_params_set_access(data->pcmHandle, p, SND_PCM_ACCESS_RW_INTERLEAVED)) < 0)
             err = "set access";
     }
@@ -466,16 +469,18 @@ static ALCboolean alsa_reset_playback(ALCdevice *device)
     /* set rate (implicitly constrains period/buffer parameters) */
     if(err == NULL && (i=psnd_pcm_hw_params_set_rate_near(data->pcmHandle, p, &rate, NULL)) < 0)
         err = "set rate near";
-    /* set buffer size in frame units (implicitly sets period size/bytes/time and buffer time/bytes) */
+    /* set period size in frame units (implicitly sets buffer size/bytes/time and period time/bytes) */
-    if(err == NULL && (i=psnd_pcm_hw_params_set_buffer_size_near(data->pcmHandle, p, &bufferSizeInFrames)) < 0)
+    if(err == NULL && (i=psnd_pcm_hw_params_set_period_size_near(data->pcmHandle, p, &periodSizeInFrames, NULL)) < 0)
-        err = "set buffer size near";
+        err = "set period size near";
     /* install and prepare hardware configuration */
     if(err == NULL && (i=psnd_pcm_hw_params(data->pcmHandle, p)) < 0)
         err = "set params";
     if(err == NULL && (i=psnd_pcm_hw_params_get_access(p, &access)) < 0)
         err = "get access";
-    if(err == NULL && (i=psnd_pcm_hw_params_get_period_size(p, &bufferSizeInFrames, NULL)) < 0)
+    if(err == NULL && (i=psnd_pcm_hw_params_get_period_size(p, &periodSizeInFrames, NULL)) < 0)
         err = "get period size";
+    if(err == NULL && (i=psnd_pcm_hw_params_get_periods(p, &periods, NULL)) < 0)
+        err = "get periods";
     if(err != NULL)
     {
         AL_PRINT("%s failed: %s\n", err, psnd_strerror(i));
@@ -490,7 +495,7 @@ static ALCboolean alsa_reset_playback(ALCdevice *device)
 
     if((i=psnd_pcm_sw_params_current(data->pcmHandle, sp)) != 0)
         err = "sw current";
-    if(err == NULL && (i=psnd_pcm_sw_params_set_avail_min(data->pcmHandle, sp, bufferSizeInFrames)) != 0)
+    if(err == NULL && (i=psnd_pcm_sw_params_set_avail_min(data->pcmHandle, sp, periodSizeInFrames)) != 0)
         err = "sw set avail min";
     if(err == NULL && (i=psnd_pcm_sw_params(data->pcmHandle, sp)) != 0)
         err = "sw set params";
@@ -503,15 +508,19 @@ static ALCboolean alsa_reset_playback(ALCdevice *device)
 
     psnd_pcm_sw_params_free(sp);
 
-    data->size = psnd_pcm_frames_to_bytes(data->pcmHandle, bufferSizeInFrames);
+    data->size = psnd_pcm_frames_to_bytes(data->pcmHandle, periodSizeInFrames);
     if(access == SND_PCM_ACCESS_RW_INTERLEAVED)
     {
+        /* Increase periods by one, since the temp buffer counts as an extra
+         * period */
+        periods++;
         data->buffer = malloc(data->size);
         if(!data->buffer)
         {
             AL_PRINT("buffer malloc failed\n");
             return ALC_FALSE;
         }
+        data->thread = StartThread(ALSANoMMapProc, device);
     }
     else
     {
@@ -523,12 +532,8 @@ static ALCboolean alsa_reset_playback(ALCdevice *device)
             data->buffer = NULL;
             return ALC_FALSE;
         }
-    }
-
-    if(access == SND_PCM_ACCESS_RW_INTERLEAVED)
-        data->thread = StartThread(ALSANoMMapProc, device);
-    else
         data->thread = StartThread(ALSAProc, device);
+    }
     if(data->thread == NULL)
     {
         AL_PRINT("Could not create playback thread\n");
@@ -537,7 +542,8 @@ static ALCboolean alsa_reset_playback(ALCdevice *device)
         return ALC_FALSE;
     }
 
-    device->UpdateSize = bufferSizeInFrames;
+    device->UpdateSize = periodSizeInFrames;
+    device->NumUpdates = periods;
     device->Frequency = rate;
 
     return ALC_TRUE;
@@ -631,7 +637,7 @@ open_alsa:
     }
 
     err = NULL;
-    bufferSizeInFrames = pDevice->BufferSize;
+    bufferSizeInFrames = pDevice->UpdateSize * pDevice->NumUpdates;
     psnd_pcm_hw_params_malloc(&p);
 
     if((i=psnd_pcm_hw_params_any(data->pcmHandle, p)) < 0)
@@ -677,7 +683,7 @@ open_alsa:
     frameSize  = aluChannelsFromFormat(pDevice->Format);
     frameSize *= aluBytesFromFormat(pDevice->Format);
 
-    data->ring = CreateRingBuffer(frameSize, pDevice->BufferSize);
+    data->ring = CreateRingBuffer(frameSize, bufferSizeInFrames);
     if(!data->ring)
     {
         AL_PRINT("ring buffer create failed\n");
@@ -815,9 +821,11 @@ LOAD_FUNC(snd_pcm_hw_params_set_rate_near);
 LOAD_FUNC(snd_pcm_hw_params_set_rate);
 LOAD_FUNC(snd_pcm_hw_params_set_buffer_size_near);
 LOAD_FUNC(snd_pcm_hw_params_set_buffer_size_min);
+LOAD_FUNC(snd_pcm_hw_params_set_period_size_near);
 LOAD_FUNC(snd_pcm_hw_params_get_buffer_size);
 LOAD_FUNC(snd_pcm_hw_params_get_period_size);
 LOAD_FUNC(snd_pcm_hw_params_get_access);
+LOAD_FUNC(snd_pcm_hw_params_get_periods);
 LOAD_FUNC(snd_pcm_hw_params);
 LOAD_FUNC(snd_pcm_sw_params_malloc);
 LOAD_FUNC(snd_pcm_sw_params_current);

Alc/dsound.c

@@ -51,8 +51,6 @@ static void *ds_handle;
 static HRESULT (WINAPI *pDirectSoundCreate)(LPCGUID pcGuidDevice, LPDIRECTSOUND *ppDS, LPUNKNOWN pUnkOuter);
 static HRESULT (WINAPI *pDirectSoundEnumerateA)(LPDSENUMCALLBACKA pDSEnumCallback, LPVOID pContext);
 
-// Since DSound doesn't report the fragment size, emulate it
-static int num_frags;
 
 typedef struct {
     // DirectSound Playback Device
@@ -98,10 +96,10 @@ static ALuint DSoundProc(ALvoid *ptr)
         aluHandleDisconnect(pDevice);
         return 1;
     }
-    FragSize = DSBCaps.dwBufferBytes / num_frags;
 
     FrameSize = aluChannelsFromFormat(pDevice->Format) *
                 aluBytesFromFormat(pDevice->Format);
+    FragSize = pDevice->UpdateSize * FrameSize;
 
     IDirectSoundBuffer_GetCurrentPosition(pData->DSsbuffer, &LastCursor, NULL);
     while(!pData->killNow)
@@ -344,10 +342,13 @@ static ALCboolean DSoundResetPlayback(ALCdevice *device)
 
     if(SUCCEEDED(hr))
     {
+        DWORD num_frags = GetConfigValueInt("dsound", "periods", device->NumUpdates);
+        if(num_frags < 2) num_frags = 2;
+
         memset(&DSBDescription,0,sizeof(DSBUFFERDESC));
         DSBDescription.dwSize=sizeof(DSBUFFERDESC);
         DSBDescription.dwFlags=DSBCAPS_GLOBALFOCUS|DSBCAPS_GETCURRENTPOSITION2;
-        DSBDescription.dwBufferBytes=(device->BufferSize/num_frags) * num_frags * frameSize;
+        DSBDescription.dwBufferBytes=device->UpdateSize * device->NumUpdates * frameSize;
         DSBDescription.lpwfxFormat=&OutputType.Format;
         hr = IDirectSound_CreateSoundBuffer(pData->lpDS, &DSBDescription, &pData->DSsbuffer, NULL);
     }
@@ -375,7 +376,6 @@ static ALCboolean DSoundResetPlayback(ALCdevice *device)
     }
 
     device->Format = format;
-    device->UpdateSize = device->BufferSize/num_frags;
 
     return ALC_TRUE;
 }
@@ -505,9 +505,6 @@ void alcDSoundInit(BackendFuncs *FuncList)
 LOAD_FUNC(DirectSoundCreate);
 LOAD_FUNC(DirectSoundEnumerateA);
 #undef LOAD_FUNC
-
-    num_frags = GetConfigValueInt("dsound", "periods", 4);
-    if(num_frags < 2) num_frags = 2;
 }
 
 void alcDSoundDeinit(void)

Alc/oss.c

@@ -221,18 +221,19 @@ static ALCboolean oss_reset_playback(ALCdevice *device)
             AL_PRINT("Unknown format?! %x\n", device->Format);
     }
 
-    periods = GetConfigValueInt("oss", "periods", 4);
+    periods = GetConfigValueInt("oss", "periods", device->NumUpdates);
-    if((int)periods <= 0)
+    if((int)periods < 2)
         periods = 4;
     numChannels = aluChannelsFromFormat(device->Format);
     frameSize = numChannels * aluBytesFromFormat(device->Format);
 
     ossSpeed = device->Frequency;
-    log2FragmentSize = log2i(device->BufferSize * frameSize / periods);
+    log2FragmentSize = log2i(device->UpdateSize * frameSize);
 
     /* according to the OSS spec, 16 bytes are the minimum */
     if (log2FragmentSize < 4)
         log2FragmentSize = 4;
+    if(periods > 2) periods--;
     numFragmentsLogSize = (periods << 16) | log2FragmentSize;
 
 #define ok(func, str) (i=(func),((i<0)?(err=(str)),0:1))
@@ -262,6 +263,7 @@ static ALCboolean oss_reset_playback(ALCdevice *device)
 
     device->Frequency = ossSpeed;
     device->UpdateSize = info.fragsize / frameSize;
+    device->NumUpdates = info.fragments + 1;
 
     data->data_size = device->UpdateSize * frameSize;
     data->mix_data = calloc(1, data->data_size);
@@ -343,7 +345,8 @@ static ALCboolean oss_open_capture(ALCdevice *device, const ALCchar *deviceName)
     numChannels = aluChannelsFromFormat(device->Format);
     frameSize = numChannels * aluBytesFromFormat(device->Format);
     ossSpeed = device->Frequency;
-    log2FragmentSize = log2i(device->BufferSize * frameSize / periods);
+    log2FragmentSize = log2i(device->UpdateSize * device->NumUpdates *
+                             frameSize / periods);
 
     /* according to the OSS spec, 16 bytes are the minimum */
     if (log2FragmentSize < 4)
@@ -381,7 +384,7 @@ static ALCboolean oss_open_capture(ALCdevice *device, const ALCchar *deviceName)
         return ALC_FALSE;
     }
 
-    data->ring = CreateRingBuffer(frameSize, device->BufferSize);
+    data->ring = CreateRingBuffer(frameSize, device->UpdateSize * device->NumUpdates);
     if(!data->ring)
     {
         AL_PRINT("ring buffer create failed\n");

Alc/portaudio.c

@@ -90,7 +90,7 @@ static ALCboolean pa_open_playback(ALCdevice *device, const ALCchar *deviceName)
     outParams.device = GetConfigValueInt("port", "device", -1);
     if(outParams.device < 0)
         outParams.device = pPa_GetDefaultOutputDevice();
-    outParams.suggestedLatency = (float)device->BufferSize /
+    outParams.suggestedLatency = (device->UpdateSize*device->NumUpdates) /
                                  (float)device->Frequency;
     outParams.hostApiSpecificStreamInfo = NULL;
 
@@ -116,8 +116,7 @@ static ALCboolean pa_open_playback(ALCdevice *device, const ALCchar *deviceName)
     outParams.channelCount = aluChannelsFromFormat(device->Format);
 
     err = pPa_OpenStream(&data->stream, NULL, &outParams, device->Frequency,
-                         device->BufferSize/periods, paNoFlag,
+                         device->UpdateSize, paNoFlag, pa_callback, device);
-                         pa_callback, device);
     if(err != paNoError)
     {
         AL_PRINT("Pa_OpenStream() returned an error: %s\n", pPa_GetErrorText(err));
@@ -138,7 +137,6 @@ static ALCboolean pa_open_playback(ALCdevice *device, const ALCchar *deviceName)
     }
 
     device->szDeviceName = strdup(deviceName);
-    device->UpdateSize = device->BufferSize/periods;
     device->Frequency = streamInfo->sampleRate;
     return ALC_TRUE;
 }

Alc/pulseaudio.c

@@ -342,17 +342,13 @@ static ALCboolean pulse_reset_playback(ALCdevice *device) //{{{
 
     ppa_threaded_mainloop_lock(data->loop);
 
-    data->samples = device->BufferSize;
     data->frame_size = aluBytesFromFormat(device->Format) *
                        aluChannelsFromFormat(device->Format);
-
-    device->UpdateSize = device->BufferSize / 4;
-
     data->attr.minreq = -1;
     data->attr.prebuf = -1;
     data->attr.maxlength = -1;
     data->attr.fragsize = data->frame_size * device->UpdateSize;
-    data->attr.tlength = data->attr.fragsize * 4;
+    data->attr.tlength = data->attr.fragsize * device->NumUpdates;
     data->stream_name = "Playback Stream";
 
     data->spec.rate = device->Frequency;
@@ -464,7 +460,7 @@ static ALCboolean pulse_open_capture(ALCdevice *device, const ALCchar *device_na
     data = device->ExtraData;
     ppa_threaded_mainloop_lock(data->loop);
 
-    data->samples = device->BufferSize;
+    data->samples = device->UpdateSize * device->NumUpdates;
     data->frame_size = aluBytesFromFormat(device->Format) *
                        aluChannelsFromFormat(device->Format);
 

Alc/solaris.c

@@ -167,7 +167,7 @@ static ALCboolean solaris_reset_playback(ALCdevice *device)
     info.play.channels = numChannels;
 
     frameSize = numChannels * aluBytesFromFormat(device->Format);
-    info.play.buffer_size = device->BufferSize * frameSize;
+    info.play.buffer_size = device->UpdateSize*device->NumUpdates * frameSize;
 
     if(ioctl(data->fd, AUDIO_SETINFO, &info) < 0)
     {
@@ -189,7 +189,7 @@ static ALCboolean solaris_reset_playback(ALCdevice *device)
     }
 
     device->Frequency = info.play.sample_rate;
-    device->UpdateSize = info.play.buffer_size / 4;
+    device->UpdateSize = (info.play.buffer_size/device->NumUpdates) + 1;
 
     data->data_size = device->UpdateSize * frameSize;
     data->mix_data = calloc(1, data->data_size);

Alc/wave.c

@@ -219,8 +219,6 @@ static ALCboolean wave_reset_playback(ALCdevice *device)
 
     data->DataStart = ftell(data->f);
 
-    device->UpdateSize = device->BufferSize / 4;
-
     data->size = device->UpdateSize * channels * bits / 8;
     data->buffer = malloc(data->size);
     if(!data->buffer)

Alc/winmm.c

@@ -229,7 +229,8 @@ static ALCboolean WinMMOpenCapture(ALCdevice *pDevice, const ALCchar *deviceName
         goto failure;
 
     // Allocate circular memory buffer for the captured audio
-    pData->ulCapturedDataSize = pDevice->BufferSize * wfexCaptureFormat.nBlockAlign;
+    pData->ulCapturedDataSize = pDevice->UpdateSize*pDevice->NumUpdates *
+                                wfexCaptureFormat.nBlockAlign;
 
     // Make sure circular buffer is at least 100ms in size (and an exact multiple of
     // the block alignment

OpenAL32/Include/alMain.h

@@ -210,7 +210,7 @@ struct ALCdevice_struct
 
     ALuint       Frequency;
     ALuint       UpdateSize;
-    ALuint       BufferSize;
+    ALuint       NumUpdates;
     ALenum       Format;
 
     ALCchar      *szDeviceName;

alsoftrc.sample

@@ -52,10 +52,17 @@
 #  Sets the output frequency.
 #frequency = 44100
 
-## refresh:
+## period_size:
-#  Sets the buffer size, in frames. Note that the actual granularity may or may
+#  Sets the update period size, in frames. This is the number of frames needed
-#  not be less than this.
+#  for each mixing update. If the deprecated 'refresh' option is specified and
-#refresh = 4096
+#  this isn't, the value will be calculated as size = refresh/periods.
+#period_size = 1024
+
+## periods:
+#  Sets the number of update periods. Higher values create a larger mix ahead,
+#  which helps protect against skips when the CPU is under load, but increases
+#  the delay between a sound getting mixed and being heard.
+#periods = 4
 
 ## sources:
 #  Sets the maximum number of allocatable sources. Lower values may help for
@@ -136,11 +143,6 @@
 #  Sets the device name for the default playback device.
 #device = default
 
-## periods:
-#  Sets the number of update buffers for playback. A value of 0 means auto-
-#  select.
-#periods = 0
-
 ## capture:
 #  Sets the device name for the default capture device.
 #capture = default
@@ -161,10 +163,6 @@
 #  Sets the device name for OSS output.
 #device = /dev/dsp
 
-## periods:
-#  Sets the number of update buffers.
-#periods = 4
-
 ## capture:
 #  Sets the device name for OSS capture.
 #capture = /dev/dsp
@@ -178,13 +176,11 @@
 #  Sets the device name for Solaris output.
 #device = /dev/audio
 
+##
 ## DirectSound backend stuff
+##
 [dsound]
 
-## periods:
-#  Sets the number of updates for the output buffer.
-#periods = 4
-
 ##
 ## Windows Multimedia backend stuff
 ##
@@ -200,10 +196,6 @@
 #  given by PortAudio itself.
 #device = -1
 
-## periods:
-#  Sets the number of update buffers.
-#periods = 4
-
 ##
 ## PulseAudio backend stuff
 ##