add fmdsp fft analyzer

1 files changed, 57 insertions, 0 deletions

diff --git a/fmdsp/fmdsp_platform_win.c b/fmdsp/fmdsp_platform_win.c
new file mode 100644
index 0000000..3dc4074
--- /dev/null
+++ b/fmdsp/fmdsp_platform_win.c
@@ -0,0 +1,57 @@
+#include "fmdsp_platform_info.h"
+#include <stdint.h>
+#include <limits.h>
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+
+static struct {
+  HANDLE currproc;
+  uint64_t lastall;
+  uint64_t lastcpu;
+  uint64_t lastfpstime;
+} g;
+
+int fmdsp_cpu_usage(void) {
+  if (!g.currproc) g.currproc = GetCurrentProcess();
+  FILETIME ft_sys, ft_creat, ft_exit, ft_kern, ft_user;
+  GetSystemTimeAsFileTime(&ft_sys);
+  GetProcessTimes(g.currproc, &ft_creat, &ft_exit, &ft_kern, &ft_user);
+  uint64_t all = ft_sys.dwHighDateTime;
+  all <<= 32;
+  all |= ft_sys.dwLowDateTime;
+  uint64_t kern = ft_kern.dwHighDateTime;
+  kern <<= 32;
+  kern |= ft_kern.dwLowDateTime;
+  uint64_t user = ft_user.dwHighDateTime;
+  user <<= 32;
+  user |= ft_user.dwLowDateTime;
+  uint64_t cpu = kern + user;
+  uint64_t alld = all - g.lastall;
+  uint64_t cpud = cpu - g.lastcpu;
+  int percentage = 0;
+  if (alld) percentage = cpud * 100 / alld;
+  g.lastall = all;
+  g.lastcpu = cpu;
+  if (!g.lastall) return 0;
+  if (percentage > INT_MAX) percentage = INT_MAX;
+  if (percentage < 0) percentage = 0;
+  return percentage;
+}
+
+int fmdsp_fps_30(void) {
+  FILETIME ft;
+  GetSystemTimeAsFileTime(&ft);
+  uint64_t time = ft.dwHighDateTime;
+  time <<= 32;
+  time |= ft.dwLowDateTime;
+  uint64_t fps = 0;
+  if (g.lastfpstime) {
+    uint64_t diff = time - g.lastfpstime;
+    if (diff) {
+      fps = 30ull * 10000000ull / diff;
+    }
+  }
+  g.lastfpstime = time;
+  if (fps > INT_MAX) fps = INT_MAX;
+  return fps;
+}