Add a PortAudio backend

Alc/ALc.c

@@ -68,6 +68,9 @@ static struct {
 #ifdef HAVE_WINMM
     { "winmm", alcWinMMInit, EmptyFuncs },
 #endif
+#ifdef HAVE_PORTAUDIO
+    { "port", alc_pa_init, EmptyFuncs },
+#endif
 #ifdef HAVE_SDL
     { "sdl", alc_sdl_init, EmptyFuncs },
 #endif

Alc/portaudio.c

@@ -0,0 +1,239 @@
+/**
+ * OpenAL cross platform audio library
+ * Copyright (C) 1999-2007 by authors.
+ * This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Library General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ *  License along with this library; if not, write to the
+ *  Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ *  Boston, MA  02111-1307, USA.
+ * Or go to http://www.gnu.org/copyleft/lgpl.html
+ */
+
+#include "config.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "alMain.h"
+#include "AL/al.h"
+#include "AL/alc.h"
+#ifdef HAVE_DLFCN_H
+#include <dlfcn.h>
+#endif
+
+#include <portaudio.h>
+
+static void *pa_handle;
+#define MAKE_FUNC(x) static typeof(x) * p##x
+MAKE_FUNC(Pa_Initialize);
+MAKE_FUNC(Pa_GetErrorText);
+MAKE_FUNC(Pa_StartStream);
+MAKE_FUNC(Pa_StopStream);
+MAKE_FUNC(Pa_OpenStream);
+MAKE_FUNC(Pa_CloseStream);
+MAKE_FUNC(Pa_GetDefaultOutputDevice);
+#undef MAKE_FUNC
+
+
+static char *pa_device;
+
+typedef struct {
+    PaStream *stream;
+} pa_data;
+
+
+static int pa_callback(const void *inputBuffer, void *outputBuffer,
+                       unsigned long framesPerBuffer, const PaStreamCallbackTimeInfo *timeInfo,
+                       const PaStreamCallbackFlags statusFlags, void *userData)
+{
+    ALCdevice *device = (ALCdevice*)userData;
+    int frameSize;
+
+    (void)inputBuffer;
+    (void)timeInfo;
+    (void)statusFlags;
+
+    frameSize  = aluBytesFromFormat(device->Format);
+    frameSize *= aluChannelsFromFormat(device->Format);
+
+    SuspendContext(NULL);
+    aluMixData(device->Context, outputBuffer, framesPerBuffer*frameSize, device->Format);
+    ProcessContext(NULL);
+
+    return 0;
+}
+
+
+static ALCboolean pa_open_playback(ALCdevice *device, const ALCchar *deviceName)
+{
+    PaStreamParameters outParams;
+    pa_data *data;
+    int periods;
+    PaError err;
+
+    if(pa_handle == NULL)
+        return ALC_FALSE;
+
+    if(deviceName)
+    {
+        if(strcmp(deviceName, pa_device) != 0)
+            return ALC_FALSE;
+    }
+
+    device->szDeviceName = pa_device;
+
+    data = (pa_data*)calloc(1, sizeof(pa_data));
+    device->ExtraData = data;
+
+    outParams.device = GetConfigValueInt("port", "device", -1);
+    if(outParams.device < 0)
+        outParams.device = pPa_GetDefaultOutputDevice();
+    outParams.suggestedLatency = (float)device->UpdateSize /
+                                 (float)device->Frequency;
+    outParams.hostApiSpecificStreamInfo = NULL;
+
+    switch(aluBytesFromFormat(device->Format))
+    {
+        case 1:
+            outParams.sampleFormat = paUInt8;
+            break;
+        case 2:
+            outParams.sampleFormat = paInt16;
+            break;
+        default:
+            outParams.sampleFormat = -1;
+            AL_PRINT("Unknown format?! %x\n", device->Format);
+    }
+
+    periods = GetConfigValueInt("port", "periods", 4);
+    if((int)periods <= 0)
+        periods = 4;
+    outParams.channelCount = aluChannelsFromFormat(device->Format);
+
+    err = pPa_OpenStream(&data->stream, NULL, &outParams, device->Frequency,
+                        device->UpdateSize/periods, paNoFlag,
+                        pa_callback, device);
+    if(err != paNoError)
+    {
+        AL_PRINT("Pa_OpenStream() returned an error: %s\n", pPa_GetErrorText(err));
+        device->ExtraData = NULL;
+        free(data);
+        return ALC_FALSE;
+    }
+
+    err = pPa_StartStream(data->stream);
+    if(err != paNoError)
+    {
+        AL_PRINT("Pa_StartStream() returned an error: %s\n", pPa_GetErrorText(err));
+        pPa_CloseStream(data->stream);
+        device->ExtraData = NULL;
+        free(data);
+        return ALC_FALSE;
+    }
+
+    device->UpdateSize /= periods;
+    return ALC_TRUE;
+}
+
+static void pa_close_playback(ALCdevice *device)
+{
+    pa_data *data = (pa_data*)device->ExtraData;
+    PaError err;
+
+    err = pPa_StopStream(data->stream);
+    if(err != paNoError)
+      fprintf(stderr, "Error stopping stream: %s\n", pPa_GetErrorText(err));
+
+    err = pPa_CloseStream(data->stream);
+    if(err != paNoError)
+        fprintf(stderr, "Error closing stream: %s\n", pPa_GetErrorText(err));
+
+    free(data);
+    device->ExtraData = NULL;
+}
+
+
+static ALCboolean pa_open_capture(ALCdevice *device, const ALCchar *deviceName, ALCuint frequency, ALCenum format, ALCsizei SampleSize)
+{
+    return ALC_FALSE;
+    (void)device;
+    (void)deviceName;
+    (void)frequency;
+    (void)format;
+    (void)SampleSize;
+}
+
+
+
+static const BackendFuncs pa_funcs = {
+    pa_open_playback,
+    pa_close_playback,
+    pa_open_capture,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL
+};
+
+void alc_pa_init(BackendFuncs *func_list)
+{
+    const char *str;
+    PaError err;
+
+    *func_list = pa_funcs;
+
+#ifdef HAVE_DLFCN_H
+#if defined(__APPLE__) && defined(__MACH__)
+# define PALIB "libportaudio.2.dylib"
+#else
+# define PALIB "libportaudio.so.2"
+#endif
+    pa_handle = dlopen(PALIB, RTLD_NOW);
+    if(!pa_handle)
+        return;
+    dlerror();
+
+#define LOAD_FUNC(f) do { \
+    p##f = (typeof(f)*)dlsym(pa_handle, #f); \
+    if((str=dlerror()) != NULL) \
+    { \
+        dlclose(pa_handle); \
+        pa_handle = NULL; \
+        AL_PRINT("Could not load %s from "PALIB": %s\n", #f, str); \
+        return; \
+    } \
+} while(0)
+#else
+    str = NULL;
+    pa_handle = 0xDEADBEEF;
+#define LOAD_FUNC(f) p##f = f
+#endif
+
+    LOAD_FUNC(Pa_Initialize);
+    LOAD_FUNC(Pa_GetErrorText);
+    LOAD_FUNC(Pa_StartStream);
+    LOAD_FUNC(Pa_StopStream);
+    LOAD_FUNC(Pa_OpenStream);
+    LOAD_FUNC(Pa_CloseStream);
+    LOAD_FUNC(Pa_GetDefaultOutputDevice);
+#undef LOAD_FUNC
+
+    if((err=pPa_Initialize()) != paNoError)
+    {
+        AL_PRINT("Pa_Initialize() returned an error: %s\n", pPa_GetErrorText(err));
+        return;
+    }
+
+    pa_device = AppendDeviceList("PortAudio Software");
+    AppendAllDeviceList(pa_device);
+}

CMakeLists.txt

@@ -26,6 +26,7 @@ OPTION(OSS     "Check for OSS backend"                 ON)
 OPTION(SOLARIS "Check for Solaris backend"             ON)
 OPTION(DSOUND  "Check for DirectSound backend"         ON)
 OPTION(WINMM   "Check for Windows Multimedia backend"  ON)
+OPTION(PORTAUDIO "Check for PortAudio backend"         ON)
 OPTION(SDL     "Check for SDL backend"                 ON)
 
 OPTION(DLOPEN  "Check for the dlopen API for loading optional libs"  ON)
@@ -321,6 +322,24 @@ IF(HAVE_WINDOWS_H)
     ENDIF()
 ENDIF()
 
+# Check PortAudio backend
+IF(PORTAUDIO)
+    CHECK_INCLUDE_FILE(portaudio.h HAVE_PORTAUDIO_H)
+    IF(HAVE_PORTAUDIO_H)
+        CHECK_LIBRARY_EXISTS(portaudio Pa_Initialize "" HAVE_LIBPORTAUDIO)
+        IF(HAVE_LIBPORTAUDIO)
+            SET(HAVE_PORTAUDIO 1)
+            SET(ALC_OBJS  ${ALC_OBJS} Alc/portaudio.c)
+            IF(HAVE_DLFCN_H)
+                SET(BACKENDS  "${BACKENDS} PortAudio,")
+            ELSE()
+                SET(BACKENDS  "${BACKENDS} PortAudio \(linked\),")
+                SET(EXTRA_LIBS portaudio ${EXTRA_LIBS})
+            ENDIF()
+        ENDIF()
+    ENDIF()
+ENDIF()
+
 # Check SDL backend
 IF(SDL)
     CHECK_INCLUDE_FILE(SDL.h HAVE_SDL_H)

OpenAL32/Include/alMain.h

@@ -150,6 +150,7 @@ void alc_oss_init(BackendFuncs *func_list);
 void alc_solaris_init(BackendFuncs *func_list);
 void alcDSoundInit(BackendFuncs *func_list);
 void alcWinMMInit(BackendFuncs *FuncList);
+void alc_pa_init(BackendFuncs *func_list);
 void alc_sdl_init(BackendFuncs *func_list);
 void alc_wave_init(BackendFuncs *func_list);
 

alsoftrc.sample

@@ -136,6 +136,12 @@ periods = 4  # Sets the number of updates for the output buffer. Default is 4
 [winmm]  # Windows Multimedia backend stuff
          # Nothing yet...
 
+[port]  # PortAudio backend stuff
+device = -1  # Sets the device index for output. Negative values will use the
+             # default as given by PortAudio itself. Default is -1
+
+periods = 4  # Sets the number of update buffers. Default is 4
+
 [sdl]  # SDL backend stuff
        # Nothing yet...
 

config.h.in

@@ -19,6 +19,9 @@
 /* Define if we have the Windows Multimedia backend */
 #cmakedefine HAVE_WINMM
 
+/* Define if we have the PortAudio backend */
+#cmakedefine HAVE_PORTAUDIO
+
 /* Define if we have the SDL backend */
 #cmakedefine HAVE_SDL