Removed distinction between "available" and "init" in audio backends,…

… since both had to be checked for success as a pair at the higher level and several of the Available methods were just always-succeed placeholders anyhow. Now the availability check is done in the init code, and the higher level tries all possible drivers until one manages to initialize successfully.
libsdl-org · Oct 17, 2006 · cda68e3 · cda68e3
1 parent 20d2eae
commit cda68e3
Show file tree

Hide file tree

Showing 28 changed files with 334 additions and 553 deletions.
diff --git a/src/audio/SDL_audio.c b/src/audio/SDL_audio.c
@@ -360,6 +360,7 @@ SDL_AudioInit(const char *driver_name)
 {
     int i = 0;
     int initialized = 0;
+    int tried_to_init = 0;
 
     if (SDL_WasInit(SDL_INIT_AUDIO)) {
         SDL_AudioQuit();  /* shutdown driver if already running. */
@@ -373,36 +374,31 @@ SDL_AudioInit(const char *driver_name)
         driver_name = SDL_getenv("SDL_AUDIODRIVER");
     }
 
-    /* !!! FIXME: what's the point of separating available() and init()? */
-    if (driver_name != NULL) {
-        for (i = 0; bootstrap[i]; ++i) {
-            if (SDL_strcasecmp(bootstrap[i]->name, driver_name) == 0) {
-                if (bootstrap[i]->available()) {
-                    SDL_memset(&current_audio, 0, sizeof (current_audio));
-                    current_audio.name = bootstrap[i]->name;
-                    current_audio.desc = bootstrap[i]->desc;
-                    initialized = bootstrap[i]->init(&current_audio.impl);
-                }
-                break;
-            }
-        }
-    } else {
-        for (i = 0; (!initialized) && (bootstrap[i]); ++i) {
-            if ((!bootstrap[i]->demand_only) && (bootstrap[i]->available())) {
-                SDL_memset(&current_audio, 0, sizeof (current_audio));
-                current_audio.name = bootstrap[i]->name;
-                current_audio.desc = bootstrap[i]->desc;
-                initialized = bootstrap[i]->init(&current_audio.impl);
-            }
+    for (i = 0; (!initialized) && (bootstrap[i]); ++i) {
+        /* make sure we should even try this driver before doing so... */
+        const AudioBootStrap *backend = bootstrap[i];
+        if ( ((driver_name) && (SDL_strcasecmp(backend->name, driver_name))) ||
+             ((!driver_name) && (backend->demand_only)) ) {
+            continue;
         }
+
+        tried_to_init = 1;
+        SDL_memset(&current_audio, 0, sizeof (current_audio));
+        current_audio.name = backend->name;
+        current_audio.desc = backend->desc;
+        initialized = backend->init(&current_audio.impl);
     }
 
     if (!initialized) {
-        if (driver_name) {
-            SDL_SetError("%s not available", driver_name);
-        } else {
-            SDL_SetError("No available audio device");
+        /* specific drivers will set the error message if they fail... */
+        if (!tried_to_init) {
+            if (driver_name) {
+                SDL_SetError("%s not available", driver_name);
+            } else {
+                SDL_SetError("No available audio device");
+            }
         }
+
         SDL_memset(&current_audio, 0, sizeof (current_audio));
         return (-1);  /* No driver was available, so fail. */
     }

diff --git a/src/audio/SDL_sysaudio.h b/src/audio/SDL_sysaudio.h
@@ -107,10 +107,10 @@ typedef struct AudioBootStrap
 {
     const char *name;
     const char *desc;
-    int (*available) (void);
     int (*init) (SDL_AudioDriverImpl *impl);
     int demand_only:1;  /* 1==request explicitly, or it won't be available. */
 } AudioBootStrap;
 
 #endif /* _SDL_sysaudio_h */
+
 /* vi: set ts=4 sw=4 expandtab: */
diff --git a/src/audio/alsa/SDL_alsa_audio.c b/src/audio/alsa/SDL_alsa_audio.c
@@ -151,12 +151,10 @@ static int load_alsa_syms(void)
 
 #ifdef SDL_AUDIO_DRIVER_ALSA_DYNAMIC
 
-static int library_load_count = 0;
-
 static void
 UnloadALSALibrary(void)
 {
-    if ((alsa_handle != NULL) && (--library_load_count == 0)) {
+    if (alsa_handle != NULL) {
         dlclose(alsa_handle);
         alsa_handle = NULL;
     }
@@ -166,10 +164,9 @@ static int
 LoadALSALibrary(void)
 {
     int retval = 0;
-    if (library_load_count++ == 0) {
+    if (alsa_handle == NULL) {
         alsa_handle = dlopen(alsa_library, RTLD_NOW);
         if (alsa_handle == NULL) {
-            library_load_count--;
             retval = -1;
             SDL_SetError("ALSA: dlopen('%s') failed: %s\n",
                           alsa_library, strerror(errno));
@@ -217,20 +214,6 @@ get_audio_device(int channels)
 }
 
 
-static int
-ALSA_Available(void)
-{
-    int available = 0;
-
-    if (LoadALSALibrary() >= 0) {
-        available = 1;
-        UnloadALSALibrary();
-    }
-    return (available);
-}
-
-
-
 /* This function waits until it is possible to write a full sound buffer */
 static void
 ALSA_WaitDevice(_THIS)
@@ -377,7 +360,6 @@ ALSA_CloseDevice(_THIS)
         }
         SDL_free(this->hidden);
         this->hidden = NULL;
-        UnloadALSALibrary();
     }
 }
 
@@ -401,11 +383,6 @@ ALSA_OpenDevice(_THIS, const char *devname, int iscapture)
     }
     SDL_memset(this->hidden, 0, (sizeof *this->hidden));
 
-    if (LoadALSALibrary() < 0) {
-        ALSA_CloseDevice(this);
-        return 0;
-    }
-
     /* Open the audio device */
     /* Name of device should depend on # channels in spec */
     status = ALSA_snd_pcm_open(&pcm_handle,
@@ -599,24 +576,34 @@ ALSA_OpenDevice(_THIS, const char *devname, int iscapture)
     return 1;
 }
 
+static void
+ALSA_Deinitialize(void)
+{
+    UnloadALSALibrary();
+}
+
 static int
 ALSA_Init(SDL_AudioDriverImpl *impl)
 {
+    if (LoadALSALibrary() < 0) {
+        return 0;
+    }
+
     /* Set the function pointers */
     impl->OpenDevice = ALSA_OpenDevice;
     impl->WaitDevice = ALSA_WaitDevice;
     impl->GetDeviceBuf = ALSA_GetDeviceBuf;
     impl->PlayDevice = ALSA_PlayDevice;
     impl->CloseDevice = ALSA_CloseDevice;
+    impl->Deinitialize = ALSA_Deinitialize;
     impl->OnlyHasDefaultOutputDevice = 1;  /* !!! FIXME: Add device enum! */
 
     return 1;
 }
 
 
 AudioBootStrap ALSA_bootstrap = {
-    DRIVER_NAME, "ALSA 0.9 PCM audio",
-    ALSA_Available, ALSA_Init, 0
+    DRIVER_NAME, "ALSA 0.9 PCM audio", ALSA_Init, 0
 };
 
 /* vi: set ts=4 sw=4 expandtab: */
diff --git a/src/audio/arts/SDL_artsaudio.c b/src/audio/arts/SDL_artsaudio.c
@@ -126,32 +126,6 @@ LoadARTSLibrary(void)
 
 #endif /* SDL_AUDIO_DRIVER_ARTS_DYNAMIC */
 
-/* Audio driver bootstrap functions */
-
-static int
-ARTS_Available(void)
-{
-    int available = 0;
-
-    if (LoadARTSLibrary() == 0) {
-        if (SDL_NAME(arts_init) () == 0) {
-#define ARTS_CRASH_HACK         /* Play a stream so aRts doesn't crash */
-#ifdef ARTS_CRASH_HACK
-            arts_stream_t stream;
-            stream = SDL_NAME(arts_play_stream) (44100, 16, 2, "SDL");
-            SDL_NAME(arts_write) (stream, "", 0);
-            SDL_NAME(arts_close_stream) (stream);
-#endif
-            available = 1;
-            SDL_NAME(arts_free) ();
-        }
-        UnloadARTSLibrary();
-    }
-
-    return available;
-}
-
-
 /* This function waits until it is possible to write a full sound buffer */
 static void
 ARTS_WaitDevice(_THIS)
@@ -232,7 +206,6 @@ ARTS_CloseDevice(_THIS)
         SDL_free(this->hidden);
         this->hidden = NULL;
     }
-    UnloadARTSLibrary();
 }
 
 
@@ -252,12 +225,6 @@ ARTS_OpenDevice(_THIS, const char *devname, int iscapture)
     }
     SDL_memset(this->hidden, 0, (sizeof *this->hidden));
 
-    if (LoadARTSLibrary() < 0) {
-        ARTS_CloseDevice(this);
-        SDL_SetError("ARTS: failed to load library: %s", SDL_GetError());
-        return 0;
-    }
-
     /* Try for a closest match on audio format */
     for (test_format = SDL_FirstAudioFormat(this->spec.format);
          !format && test_format;) {
@@ -341,25 +308,49 @@ ARTS_OpenDevice(_THIS, const char *devname, int iscapture)
 }
 
 
+static void
+ARTS_Deinitialize(void)
+{
+    UnloadARTSLibrary();
+}
+
+
 static int
 ARTS_Init(SDL_AudioDriverImpl *impl)
 {
+    if (LoadARTSLibrary() < 0) {
+        return 0;
+    } else {
+        if (SDL_NAME(arts_init) () != 0) {
+            UnloadARTSLibrary();
+            SDL_SetError("ARTS: arts_init failed (no audio server?)");
+            return 0;
+        }
+
+        /* Play a stream so aRts doesn't crash */
+        arts_stream_t stream;
+        stream = SDL_NAME(arts_play_stream) (44100, 16, 2, "SDL");
+        SDL_NAME(arts_write) (stream, "", 0);
+        SDL_NAME(arts_close_stream) (stream);
+        SDL_NAME(arts_free) ();
+    }
+
     /* Set the function pointers */
     impl->OpenDevice = ARTS_OpenDevice;
     impl->PlayDevice = ARTS_PlayDevice;
     impl->WaitDevice = ARTS_WaitDevice;
     impl->GetDeviceBuf = ARTS_GetDeviceBuf;
     impl->CloseDevice = ARTS_CloseDevice;
     impl->WaitDone = ARTS_WaitDone;
+    impl->Deinitialize = ARTS_Deinitialize;
     impl->OnlyHasDefaultOutputDevice = 1;
 
     return 1;
 }
 
 
 AudioBootStrap ARTS_bootstrap = {
-    ARTS_DRIVER_NAME, "Analog RealTime Synthesizer",
-    ARTS_Available, ARTS_Init, 0
+    ARTS_DRIVER_NAME, "Analog RealTime Synthesizer", ARTS_Init, 0
 };
 
 /* vi: set ts=4 sw=4 expandtab: */
diff --git a/src/audio/baudio/SDL_beaudio.cc b/src/audio/baudio/SDL_beaudio.cc
@@ -39,12 +39,6 @@ extern "C"
 }
 
 
-static int BEOSAUDIO_Available(void)
-{
-    return 1;  /* Always available on BeOS. */
-}
-
-
 /* !!! FIXME: have the callback call the higher level to avoid code dupe. */
 /* The BeOS callback for handling the audio buffer */
 static void
@@ -215,8 +209,7 @@ BEOSAUDIO_Init(SDL_AudioDriverImpl *impl)
 
 extern "C" { extern AudioBootStrap BEOSAUDIO_bootstrap; }
 AudioBootStrap BEOSAUDIO_bootstrap = {
-    "baudio", "BeOS BSoundPlayer",
-    BEOSAUDIO_Available, BEOSAUDIO_Init, 0
+    "baudio", "BeOS BSoundPlayer", BEOSAUDIO_Init, 0
 };
 
 /* vi: set ts=4 sw=4 expandtab: */

diff --git a/src/audio/bsd/SDL_bsdaudio.c b/src/audio/bsd/SDL_bsdaudio.c
@@ -104,17 +104,6 @@ free_device_lists(void)
 }
 
 
-static int
-BSDAUDIO_Available(void)
-{
-    int available = 0;
-    build_device_lists();
-    available = ((outputDeviceCount > 0) || (inputDeviceCount > 0));
-    free_device_lists();
-    return available;
-}
-
-
 static void
 BSDAUDIO_Deinitialize(void)
 {
@@ -443,23 +432,22 @@ static int
 BSDAUDIO_Init(SDL_AudioDriverImpl *impl)
 {
     /* Set the function pointers */
-    impl->DetectDevices = DSP_DetectDevices;
-    impl->GetDeviceName = DSP_GetDeviceName;
-    impl->OpenDevice = DSP_OpenDevice;
-    impl->PlayDevice = DSP_PlayDevice;
-    impl->WaitDevice = DSP_WaitDevice;
-    impl->GetDeviceBuf = DSP_GetDeviceBuf;
-    impl->CloseDevice = DSP_CloseDevice;
-    impl->Deinitialize = DSP_Deinitialize;
+    impl->DetectDevices = BSDAUDIO_DetectDevices;
+    impl->GetDeviceName = BSDAUDIO_GetDeviceName;
+    impl->OpenDevice = BSDAUDIO_OpenDevice;
+    impl->PlayDevice = BSDAUDIO_PlayDevice;
+    impl->WaitDevice = BSDAUDIO_WaitDevice;
+    impl->GetDeviceBuf = BSDAUDIO_GetDeviceBuf;
+    impl->CloseDevice = BSDAUDIO_CloseDevice;
+    impl->Deinitialize = BSDAUDIO_Deinitialize;
 
     build_device_lists();
     return 1;
 }
 
 
 AudioBootStrap BSD_AUDIO_bootstrap = {
-    BSD_AUDIO_DRIVER_NAME, BSD_AUDIO_DRIVER_DESC,
-    BSDAUDIO_Available, BSDAUDIO_Init, 0
+    BSD_AUDIO_DRIVER_NAME, BSD_AUDIO_DRIVER_DESC, BSDAUDIO_Init, 0
 };
 
 /* vi: set ts=4 sw=4 expandtab: */
diff --git a/src/audio/dart/SDL_dart.c b/src/audio/dart/SDL_dart.c
@@ -427,11 +427,6 @@ DART_CloseDevice(_THIS)
     }
 }
 
-static int
-DART_Available(void)
-{
-    return 1;  /* Always available on OS/2 Warp */
-}
 
 static int
 DART_Init(SDL_AudioDriverImpl *impl)
@@ -451,8 +446,7 @@ DART_Init(SDL_AudioDriverImpl *impl)
 
 
 AudioBootStrap DART_bootstrap = {
-    "dart", "OS/2 Direct Audio RouTines (DART)",
-    DART_Available, DART_Init, 0
+    "dart", "OS/2 Direct Audio RouTines (DART)", DART_Init, 0
 };
 
 /* vi: set ts=4 sw=4 expandtab: */