Add Get/SetUniqueIdForProcess.

base/process/process_handle.cc

Index: base/process/process_handle.cc
diff --git a/base/process/process_handle.cc b/base/process/process_handle.cc
new file mode 100644
index 0000000000000000000000000000000000000000..8b960283c90937b82bb784649892ac6fff93abf5
--- /dev/null
+++ b/base/process/process_handle.cc
@@ -0,0 +1,40 @@
+// Copyright (c) 2013 The Chromium Authors. All rights reserved.

[jln (very slow on Chromium), 2015/06/16 22:59:01]

New file, so remove (c) and use 2015

[rickyz (no longer on Chrome), 2015/06/17 00:50:34]

Done.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/logging.h"
+#include "base/process/process_handle.h"

[jln (very slow on Chromium), 2015/06/16 22:59:01]

Don't forget basictypes.h

[rickyz (no longer on Chrome), 2015/06/17 00:50:34]

Done.

+
+namespace base {
+
+namespace {
+uint32 g_unique_id = kInvalidUniqueId;
+
+#ifndef NDEBUG
+// The process which set g_unique_id.
+uint32 g_procid;
+#endif
+}  // namespace
+
+uint32 GetUniqueIdForProcess() {
+  if (g_unique_id == kInvalidUniqueId) {
+    return static_cast<uint32>(GetCurrentProcId());
+  }
+
+#ifndef NDEBUG
+  // Make sure we are the same process that set g_procid. This check may have
+  // false negatives (if a process ID was reused) but should have no false
+  // positives.
+  DCHECK_EQ(static_cast<uint32>(GetCurrentProcId()), g_procid);
+#endif
+  return g_unique_id;
+}
+
+void SetUniqueIdForProcess(uint32 unique_id) {
+  g_unique_id = unique_id;
+#ifndef NDEBUG
+  g_procid = static_cast<uint32>(GetCurrentProcId());
+#endif
+}
+
+}  // namespace base