Initial commit

2 files changed, 169 insertions, 0 deletions

diff --git a/contrib/SDL-3.2.8/src/audio/dummy/SDL_dummyaudio.c b/contrib/SDL-3.2.8/src/audio/dummy/SDL_dummyaudio.c
new file mode 100644
index 0000000..d0f1a1a
--- /dev/null
+++ b/contrib/SDL-3.2.8/src/audio/dummy/SDL_dummyaudio.c
@@ -0,0 +1,135 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2025 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+#include "SDL_internal.h"
+
+// Output audio to nowhere...
+
+#include "../SDL_sysaudio.h"
+#include "SDL_dummyaudio.h"
+
+#if defined(SDL_PLATFORM_EMSCRIPTEN) && !defined(__EMSCRIPTEN_PTHREADS__)
+#include <emscripten/emscripten.h>
+#endif
+
+static bool DUMMYAUDIO_WaitDevice(SDL_AudioDevice *device)
+{
+    SDL_Delay(device->hidden->io_delay);
+    return true;
+}
+
+static bool DUMMYAUDIO_OpenDevice(SDL_AudioDevice *device)
+{
+    device->hidden = (struct SDL_PrivateAudioData *) SDL_calloc(1, sizeof(*device->hidden));
+    if (!device->hidden) {
+        return false;
+    }
+
+    if (!device->recording) {
+        device->hidden->mixbuf = (Uint8 *) SDL_malloc(device->buffer_size);
+        if (!device->hidden->mixbuf) {
+            return false;
+        }
+    }
+
+    device->hidden->io_delay = ((device->sample_frames * 1000) / device->spec.freq);
+
+    const char *hint = SDL_GetHint(SDL_HINT_AUDIO_DUMMY_TIMESCALE);
+    if (hint) {
+        double scale = SDL_atof(hint);
+        if (scale >= 0.0) {
+            device->hidden->io_delay = (Uint32)SDL_round(device->hidden->io_delay * scale);
+        }
+    }
+
+    // on Emscripten without threads, we just fire a repeating timer to consume audio.
+    #if defined(SDL_PLATFORM_EMSCRIPTEN) && !defined(__EMSCRIPTEN_PTHREADS__)
+    MAIN_THREAD_EM_ASM({
+        var a = Module['SDL3'].dummy_audio;
+        if (a.timers[$0] !== undefined) { clearInterval(a.timers[$0]); }
+        a.timers[$0] = setInterval(function() { dynCall('vi', $3, [$4]); }, ($1 / $2) * 1000);
+    }, device->recording ? 1 : 0, device->sample_frames, device->spec.freq, device->recording ? SDL_RecordingAudioThreadIterate : SDL_PlaybackAudioThreadIterate, device);
+    #endif
+
+    return true; // we're good; don't change reported device format.
+}
+
+static void DUMMYAUDIO_CloseDevice(SDL_AudioDevice *device)
+{
+    if (device->hidden) {
+        // on Emscripten without threads, we just fire a repeating timer to consume audio.
+        #if defined(SDL_PLATFORM_EMSCRIPTEN) && !defined(__EMSCRIPTEN_PTHREADS__)
+        MAIN_THREAD_EM_ASM({
+            var a = Module['SDL3'].dummy_audio;
+            if (a.timers[$0] !== undefined) { clearInterval(a.timers[$0]); }
+            a.timers[$0] = undefined;
+        }, device->recording ? 1 : 0);
+        #endif
+        SDL_free(device->hidden->mixbuf);
+        SDL_free(device->hidden);
+        device->hidden = NULL;
+    }
+}
+
+static Uint8 *DUMMYAUDIO_GetDeviceBuf(SDL_AudioDevice *device, int *buffer_size)
+{
+    return device->hidden->mixbuf;
+}
+
+static int DUMMYAUDIO_RecordDevice(SDL_AudioDevice *device, void *buffer, int buflen)
+{
+    // always return a full buffer of silence.
+    SDL_memset(buffer, device->silence_value, buflen);
+    return buflen;
+}
+
+static bool DUMMYAUDIO_Init(SDL_AudioDriverImpl *impl)
+{
+    impl->OpenDevice = DUMMYAUDIO_OpenDevice;
+    impl->CloseDevice = DUMMYAUDIO_CloseDevice;
+    impl->WaitDevice = DUMMYAUDIO_WaitDevice;
+    impl->GetDeviceBuf = DUMMYAUDIO_GetDeviceBuf;
+    impl->WaitRecordingDevice = DUMMYAUDIO_WaitDevice;
+    impl->RecordDevice = DUMMYAUDIO_RecordDevice;
+
+    impl->OnlyHasDefaultPlaybackDevice = true;
+    impl->OnlyHasDefaultRecordingDevice = true;
+    impl->HasRecordingSupport = true;
+
+    // on Emscripten without threads, we just fire a repeating timer to consume audio.
+    #if defined(SDL_PLATFORM_EMSCRIPTEN) && !defined(__EMSCRIPTEN_PTHREADS__)
+    MAIN_THREAD_EM_ASM({
+        if (typeof(Module['SDL3']) === 'undefined') {
+            Module['SDL3'] = {};
+        }
+        Module['SDL3'].dummy_audio = {};
+        Module['SDL3'].dummy_audio.timers = [];
+        Module['SDL3'].dummy_audio.timers[0] = undefined;
+        Module['SDL3'].dummy_audio.timers[1] = undefined;
+    });
+    impl->ProvidesOwnCallbackThread = true;
+    #endif
+
+    return true;
+}
+
+AudioBootStrap DUMMYAUDIO_bootstrap = {
+    "dummy", "SDL dummy audio driver", DUMMYAUDIO_Init, true, false
+};
diff --git a/contrib/SDL-3.2.8/src/audio/dummy/SDL_dummyaudio.h b/contrib/SDL-3.2.8/src/audio/dummy/SDL_dummyaudio.h
new file mode 100644
index 0000000..d5e75c7
--- /dev/null
+++ b/contrib/SDL-3.2.8/src/audio/dummy/SDL_dummyaudio.h
@@ -0,0 +1,34 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2025 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+#include "SDL_internal.h"
+
+#ifndef SDL_dummyaudio_h_
+#define SDL_dummyaudio_h_
+
+#include "../SDL_sysaudio.h"
+
+struct SDL_PrivateAudioData
+{
+    Uint8 *mixbuf;   // The file descriptor for the audio device
+    Uint32 io_delay; // milliseconds to sleep in WaitDevice.
+};
+
+#endif // SDL_dummyaudio_h_