1 files changed, 100 insertions, 0 deletions
diff --git a/win32/waveout.c b/win32/waveout.c
new file mode 100644
index 0000000..9c96483
--- /dev/null
+++ b/win32/waveout.c
@@ -0,0 +1,100 @@
+#include "waveout.h"
+
+struct waveout_state {
+  HWAVEOUT wo;
+  DWORD firstout;
+  sound_callback cbfunc;
+  void *userptr;
+  WAVEHDR waveheaders[4];
+  int16_t *wavebuf;
+};
+
+static void CALLBACK waveout_cbproc(HWAVEOUT wo, UINT msg,
+                                 DWORD_PTR instance,
+                                 DWORD_PTR p1, DWORD_PTR p2) {
+  (void)wo;
+  (void)p2;
+  if (msg != WOM_DONE) return;
+  struct waveout_state *waveout = (struct waveout_state *)instance;
+  WAVEHDR *wh = (WAVEHDR *)p1;
+  waveout->cbfunc(waveout->userptr, (int16_t *)wh->lpData, wh->dwBufferLength/4);
+  waveOutWrite(waveout->wo, wh, sizeof(*wh));
+}
+
+struct waveout_state *waveout_init(HWND hwnd, unsigned srate, unsigned sectlen,
+                                   sound_callback cbfunc, void *userptr) {
+  HANDLE heap = GetProcessHeap();
+  struct waveout_state *waveout = HeapAlloc(heap, HEAP_ZERO_MEMORY,
+                                            sizeof(struct waveout_state));
+  if (!waveout) {
+    MessageBoxW(hwnd, L"cannot allocate memory for WaveOut", L"Error", MB_ICONSTOP);
+    goto err;
+  }
+  waveout->wavebuf = HeapAlloc(heap, HEAP_ZERO_MEMORY, sectlen*4);
+  if (!waveout->wavebuf) {
+    MessageBoxW(hwnd, L"cannot allocate buffer memory for WaveOut", L"Error", MB_ICONSTOP);
+    goto err_waveout;
+  }
+  WAVEFORMATEX format;
+  format.wFormatTag = WAVE_FORMAT_PCM;
+  format.nChannels = 2;
+  format.nSamplesPerSec = srate;
+  format.wBitsPerSample = 16;
+  format.nBlockAlign = format.nChannels * format.wBitsPerSample / 8;
+  format.nAvgBytesPerSec = format.nSamplesPerSec * format.nBlockAlign;
+  format.cbSize = 0;
+  HRESULT hr;
+  hr = waveOutOpen(&waveout->wo, WAVE_MAPPER, &format,
+                   (DWORD_PTR)waveout_cbproc, (DWORD_PTR)waveout, CALLBACK_FUNCTION);
+  if (hr != MMSYSERR_NOERROR) {
+    MessageBoxW(hwnd, L"cannot WaveOutOpen", L"Error", MB_ICONSTOP);
+    goto err_wavebuf;
+  }
+  for (int i = 0; i < 4; i++) {
+    WAVEHDR *wh = &waveout->waveheaders[i];
+    wh->lpData = ((char *)waveout->wavebuf) + sectlen*i;
+    wh->dwBufferLength = sectlen;
+    wh->dwFlags = 0;
+    waveOutPrepareHeader(waveout->wo, wh, sizeof(*wh));
+  }
+  waveout->firstout = 1;
+  waveout->cbfunc = cbfunc;
+  waveout->userptr = userptr;
+  return waveout;
+
+err_wavebuf:
+  HeapFree(heap, 0, waveout->wavebuf);
+err_waveout:
+  HeapFree(heap, 0, waveout);
+err:
+  return 0;
+}
+
+void waveout_pause(struct waveout_state *waveout, int pause) {
+  if (pause) {
+    waveOutPause(waveout->wo);
+  } else {
+    if (waveout->firstout) {
+      waveout->firstout = 0;
+      for (int i = 0; i < 4; i++) {
+        WAVEHDR *wh = &waveout->waveheaders[i];
+        waveout->cbfunc(waveout->userptr, (int16_t *)wh->lpData, wh->dwBufferLength/4);
+        waveOutWrite(waveout->wo, wh, sizeof(*wh));
+      }
+    } else {
+      waveOutRestart(waveout->wo);
+    }
+  }
+}
+
+void waveout_delete(struct waveout_state *waveout) {
+  if (!waveout) return;
+  waveout_pause(waveout, 1);
+  for (int i = 0; i < 4; i++) {
+    WAVEHDR *wh = &waveout->waveheaders[i];
+    waveOutUnprepareHeader(waveout->wo, wh, sizeof(*wh));
+  }
+  HANDLE heap = GetProcessHeap();
+  HeapFree(heap, 0, waveout->wavebuf);
+  HeapFree(heap, 0, waveout);
+}