Get printvideo audio working on Windows and MacOS

dsp/audio/cosmoaudio/test.c

@@ -0,0 +1,36 @@
+#include <errno.h>
+#include <limits.h>
+#include <math.h>
+#include <stdio.h>
+#include <time.h>
+#include "cosmoaudio.h"
+
+#ifndef M_PIf
+#define M_PIf 3.14159265358979323846f
+#endif
+
+int main() {
+
+  int hz = 44100;
+  int channels = 2;
+  struct CosmoAudio *ca;
+  if (cosmoaudio_open(&ca, hz, channels) != COSMOAUDIO_SUCCESS) {
+    fprintf(stderr, "%s: failed to open audio\n", argv[0]);
+    return 1;
+  }
+
+  int n = 1000;
+  int sample = 0;
+  float *buf = (float *)malloc(sizeof(float) * channels * n);
+  for (;;) {
+    for (int i = 0; i < 128; i++) {
+      float freq = 440;
+      float t = (float)sample++ / hz;
+      if (sample == hz)
+        sample = 0;
+      buf[i * channels] = sinf(freq * 2.f * M_PIf * t);
+      buf[i * channels + 1] = sinf(freq * 2.f * M_PIf * t);
+    }
+    cosmoaudio_write(ca, buf, 128);
+  }
+}