Import of the watch repository from Pebble

src/libc/math/round.c

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2024 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// Naive implementation, probably room for optimization...
+double round(double d) {
+  if (__builtin_floor(d) == d) {
+    return d;
+  }
+  double half;
+  if (d < 0.0) {
+    if (d > -0.5) {
+      return -0.0;
+    } else {
+      half = -0.5;
+    }
+  } else {
+    half = 0.5;
+  }
+  return __builtin_floor(d + half);
+}