2 files changed, 54 insertions, 0 deletions
diff --git a/content/public/common/sandbox_init.cc b/content/public/common/sandbox_init.cc
new file mode 100644
index 0000000..528eec7
--- /dev/null
+++ b/content/public/common/sandbox_init.cc
@@ -0,0 +1,44 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "content/public/common/sandbox_init.h"
+
+#if defined(OS_ANDROID)
+#include <unistd.h>
+#endif
+
+namespace content {
+
+IPC::PlatformFileForTransit BrokerGetFileHandleForProcess(
+    base::PlatformFile handle,
+    base::ProcessId target_process_id,
+    bool should_close_source) {
+  IPC::PlatformFileForTransit out_handle;
+#if defined(OS_WIN)
+  DWORD options = DUPLICATE_SAME_ACCESS;
+  if (should_close_source)
+    options |= DUPLICATE_CLOSE_SOURCE;
+  if (!content::BrokerDuplicateHandle(handle, target_process_id, &out_handle,
+                                      0, options)) {
+    out_handle = IPC::InvalidPlatformFileForTransit();
+  }
+#elif defined(OS_POSIX)
+  // If asked to close the source, we can simply re-use the source fd instead of
+  // dup()ing and close()ing.
+  // When we're not closing the source, we need to duplicate the handle and take
+  // ownership of that. The reason is that this function is often used to
+  // generate IPC messages, and the handle must remain valid until it's sent to
+  // the other process from the I/O thread. Without the dup, calling code might
+  // close the source handle before the message is sent, creating a race
+  // condition.
+  int fd = should_close_source ? handle : ::dup(handle);
+  out_handle = base::FileDescriptor(fd, true);
+#else
+  #error Not implemented.
+#endif
+  return out_handle;
+}
+
+}  // namespace content
+
diff --git a/content/public/common/sandbox_init.h b/content/public/common/sandbox_init.h
index 24da5a9..a6dcccc 100644
--- a/content/public/common/sandbox_init.h
+++ b/content/public/common/sandbox_init.h
@@ -9,6 +9,7 @@
 #include "base/process.h"
 #include "build/build_config.h"
 #include "content/common/content_export.h"
+#include "ipc/ipc_platform_file.h"
 
 #if defined(OS_WIN)
 namespace sandbox {
@@ -76,6 +77,15 @@ CONTENT_EXPORT void InitializeSandbox();
 
 #endif
 
+// Platform neutral wrapper for making an exact copy of a handle for use in
+// the target process. On Windows this wraps BrokerDuplicateHandle() with the
+// DUPLICATE_SAME_ACCESS flag. On posix it behaves essentially the same as
+// IPC::GetFileHandleForProcess()
+CONTENT_EXPORT IPC::PlatformFileForTransit BrokerGetFileHandleForProcess(
+    base::PlatformFile handle,
+    base::ProcessId target_process_id,
+    bool should_close_source);
+
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_COMMON_SANDBOX_INIT_H_