Refactor and cleanup codes. No functional changes.

util/random/global_id.h

@@ -0,0 +1,30 @@
+////////////////////////////////////////////////////////////////////////////////
+// Copyright 2017 Google LLC.
+//
+// This software is licensed under the terms defined in the Widevine Master
+// License Agreement. For a copy of this agreement, please contact
+// widevine-licensing@google.com.
+////////////////////////////////////////////////////////////////////////////////
+
+#ifndef UTIL_RANDOM_GLOBAL_ID_H_
+#define UTIL_RANDOM_GLOBAL_ID_H_
+
+#include "openssl/rand.h"
+
+namespace widevine {
+namespace util {
+namespace random {
+
+static uint64_t NewGlobalID() {
+  static __thread uint64_t val = 0;
+  if (val == 0) {
+    RAND_bytes(reinterpret_cast<uint8_t*>(&val), sizeof(val));
+  }
+  return val++;
+}
+
+}  // namespace random
+}  // namespace util
+}  // namespace widevine
+
+#endif  // UTIL_RANDOM_GLOBAL_ID_H_