timer: add convenience time unit conversion macros

There's a lot of wild 1e6, 1000, etc. lying around in the code. A macro
is much easier to read and understand at a glance. Add some helpers for
this. We don't need to convert everything now but there's some simple
things that can be done so they are included in this commit.

audio/out/ao_wasapi_utils.c

@@ -945,7 +945,7 @@ bool wasapi_thread_init(struct ao *ao)
 {
     struct wasapi_state *state = ao->priv;
     MP_DBG(ao, "Init wasapi thread\n");
-    int64_t retry_wait = 1000;
+    int64_t retry_wait = MP_TIME_US_TO_NS(1);
     bool align_hack = false;
     HRESULT hr;
 
@@ -1028,12 +1028,12 @@ retry:
         goto retry;
     case AUDCLNT_E_DEVICE_IN_USE:
     case AUDCLNT_E_DEVICE_INVALIDATED:
-        if (retry_wait > 8000) {
+        if (retry_wait > MP_TIME_US_TO_NS(8)) {
             MP_FATAL(ao, "Bad device retry failed\n");
             return false;
         }
         wasapi_thread_uninit(ao);
-        MP_WARN(ao, "Retrying in %"PRId64" us\n", retry_wait);
+        MP_WARN(ao, "Retrying in %"PRId64" ns\n", retry_wait);
         mp_sleep_ns(retry_wait);
         retry_wait *= 2;
         goto retry;

osdep/timer.h

@@ -50,6 +50,16 @@ void mp_end_hires_timers(int resolution_ms);
 
 #define MP_START_TIME 10 * INT64_C(1000000000)
 
+// Converts time units to nanoseconds (int64_t)
+#define MP_TIME_S_TO_NS(s) ((s) * INT64_C(1000000000))
+#define MP_TIME_MS_TO_NS(ms) ((ms) * INT64_C(1000000))
+#define MP_TIME_US_TO_NS(us) ((us) * INT64_C(1000))
+
+// Converts nanoseconds to specified time unit (double)
+#define MP_TIME_NS_TO_S(ns) ((ns) / (double)1000000000)
+#define MP_TIME_NS_TO_MS(ns) ((ns) / (double)1000000)
+#define MP_TIME_NS_TO_US(ns) ((ns) / (double)1000)
+
 // Duration of a second in mpv time.
 #define MP_SECOND_US (1000 * 1000)
 

video/out/opengl/hwdec_dxva2egl.c

@@ -343,7 +343,7 @@ static int mapper_map(struct ra_hwdec_mapper *mapper)
     // of the above StretchRect. Timeout of 8ms is required to reliably
     // render 4k on Intel Haswell, Ivybridge and Cherry Trail Atom.
     const int max_retries = 8;
-    const int64_t wait_ns = 1e6;
+    const int64_t wait_ns = MP_TIME_MS_TO_NS(1);
     int retries = 0;
     while (true) {
         hr = IDirect3DQuery9_GetData(p->query9, NULL, 0, D3DGETDATA_FLUSH);
@@ -353,7 +353,7 @@ static int mapper_map(struct ra_hwdec_mapper *mapper)
         } else if (hr == S_FALSE) {
             if (++retries > max_retries) {
                 MP_VERBOSE(mapper, "Failed to flush frame after %lld ms\n",
-                           (long long)(wait_ns * max_retries) / 1000000);
+                           (long long)MP_TIME_MS_TO_NS(wait_ns * max_retries));
                 break;
             }
             mp_sleep_ns(wait_ns);

video/out/vo_x11.c

@@ -299,7 +299,7 @@ static void wait_for_completion(struct vo *vo, int max_outstanding)
                             " for XShm completion events...\n");
                 ctx->Shm_Warned_Slow = 1;
             }
-            mp_sleep_ns(1e6);
+            mp_sleep_ns(MP_TIME_MS_TO_NS(1));
             vo_x11_check_events(vo);
         }
     }

video/out/vo_xv.c

@@ -670,7 +670,7 @@ static void wait_for_completion(struct vo *vo, int max_outstanding)
                         " for XShm completion events...\n");
                 ctx->Shm_Warned_Slow = 1;
             }
-            mp_sleep_ns(1e6);
+            mp_sleep_ns(MP_TIME_MS_TO_NS(1));
             vo_x11_check_events(vo);
         }
     }