1 files changed, 90 insertions, 0 deletions
diff --git a/win32/wavewrite.c b/win32/wavewrite.c
new file mode 100644
index 0000000..7c2d6da
--- /dev/null
+++ b/win32/wavewrite.c
@@ -0,0 +1,90 @@
+#include "wavewrite.h"
+
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#include <stdlib.h>
+
+struct wavefile {
+  HANDLE file;
+  uint32_t written_frames;
+};
+
+static void write16le(uint8_t *ptr, uint16_t data) {
+  ptr[0] = data;
+  ptr[1] = data >> 8;
+}
+
+static void write32le(uint8_t *ptr, uint32_t data) {
+  ptr[0] = data;
+  ptr[1] = data >> 8;
+  ptr[2] = data >> 16;
+  ptr[3] = data >> 24;
+}
+
+struct wavefile *wavewrite_open_w(const wchar_t *path, uint32_t samplerate) {
+  struct wavefile *wavefile = 0;
+  wavefile = malloc(sizeof(*wavefile));
+  if (!wavefile) goto err;
+  *wavefile = (struct wavefile){
+    .file = INVALID_HANDLE_VALUE
+  };
+  wavefile->file = CreateFile(path, GENERIC_WRITE, 0, 0, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, 0);
+  if (wavefile->file == INVALID_HANDLE_VALUE) goto err;
+  uint8_t waveheader[44] = {0};
+  memcpy(waveheader, "RIFF", 4);
+  memcpy(waveheader+8, "WAVE", 4);
+  memcpy(waveheader+12, "fmt ", 4);
+  write32le(waveheader+16, 16);
+  write16le(waveheader+20, 1);
+  write16le(waveheader+22, 2);
+  write32le(waveheader+24, samplerate);
+  write32le(waveheader+28, samplerate * 2 * 2);
+  write16le(waveheader+32, 4);
+  write16le(waveheader+34, 16);
+  memcpy(waveheader+36, "data", 4);
+  DWORD written;
+  if (!WriteFile(wavefile->file, waveheader, sizeof(waveheader), &written, 0) || (written != sizeof(waveheader))) {
+    goto err;
+  }
+  return wavefile;
+err:
+  if (wavefile) {
+    if (wavefile->file != INVALID_HANDLE_VALUE) CloseHandle(wavefile->file);
+    free(wavefile);
+  }
+  return 0;
+}
+
+size_t wavewrite_write(struct wavefile *wavefile, const int16_t *buf, size_t frames) {
+  if (frames >= (1ull<<(32-2))) return 0;
+  DWORD written;
+  if (!WriteFile(wavefile->file, buf, frames*4, &written, 0)) {
+    return 0;
+  }
+  uint32_t written_frames = written / 4u;
+  wavefile->written_frames += written_frames;
+  return written_frames;
+}
+
+void wavewrite_close(struct wavefile *wavefile) {
+  LONG fp;
+  uint32_t size;
+  DWORD written;
+  if ((SetFilePointer(wavefile->file, 40, &fp, FILE_BEGIN) == INVALID_SET_FILE_POINTER) || (fp != 40)) {
+    goto cleanup;
+  }
+  size = wavefile->written_frames * 4;
+  if (!WriteFile(wavefile->file, &size, sizeof(size), &written, 0) || (written != sizeof(size))) {
+    goto cleanup;
+  }
+  if ((SetFilePointer(wavefile->file, 4, &fp, FILE_BEGIN) == INVALID_SET_FILE_POINTER) || (fp != 4)) {
+    goto cleanup;
+  }
+  size += 4 + 8 + 16 + 8;
+  if (!WriteFile(wavefile->file, &size, sizeof(size), &written, 0) || (written != sizeof(size))) {
+    goto cleanup;
+  }
+cleanup:
+  CloseHandle(wavefile->file);
+  free(wavefile);
+}