import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

gfx/layers/ipc/GonkNativeHandleUtils.cpp

@@ -0,0 +1,93 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: sw=2 ts=8 et :
+ */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "GonkNativeHandleUtils.h"
+#include "mozilla/UniquePtr.h"
+#include "mozilla/Unused.h"
+
+using namespace mozilla::layers;
+
+namespace IPC {
+
+namespace {
+
+class native_handle_Delete
+{
+public:
+  void operator()(native_handle* aNativeHandle) const
+  {
+    native_handle_close(aNativeHandle); // closes file descriptors
+    native_handle_delete(aNativeHandle);
+  }
+};
+
+} // anonymous namespace
+
+void
+ParamTraits<GonkNativeHandle>::Write(Message* aMsg,
+                                const paramType& aParam)
+{
+  GonkNativeHandle handle = aParam;
+  MOZ_ASSERT(handle.IsValid());
+
+  RefPtr<GonkNativeHandle::NhObj> nhObj = handle.GetAndResetNhObj();
+  native_handle_t* nativeHandle = nhObj->GetAndResetNativeHandle();
+
+  size_t nbytes = nativeHandle->numInts * sizeof(int);
+  aMsg->WriteSize(nbytes);
+  aMsg->WriteBytes((nativeHandle->data + nativeHandle->numFds), nbytes);
+
+  for (size_t i = 0; i < static_cast<size_t>(nativeHandle->numFds); ++i) {
+    aMsg->WriteFileDescriptor(base::FileDescriptor(nativeHandle->data[i], true));
+  }
+}
+
+bool
+ParamTraits<GonkNativeHandle>::Read(const Message* aMsg,
+                               PickleIterator* aIter, paramType* aResult)
+{
+  size_t nbytes;
+  if (!aMsg->ReadSize(aIter, &nbytes)) {
+    return false;
+  }
+
+  if (nbytes % sizeof(int) != 0) {
+    return false;
+  }
+
+  size_t numInts = nbytes / sizeof(int);
+  size_t numFds = aMsg->num_fds();
+  mozilla::UniquePtr<native_handle, native_handle_Delete> nativeHandle(
+    native_handle_create(numFds, numInts));
+  if (!nativeHandle) {
+    return false;
+  }
+
+  auto data =
+    reinterpret_cast<char*>(nativeHandle->data + nativeHandle->numFds);
+  if (!aMsg->ReadBytesInto(aIter, data, nbytes)) {
+    return false;
+  }
+
+  for (size_t i = 0; i < numFds; ++i) {
+    base::FileDescriptor fd;
+    if (!aMsg->ReadFileDescriptor(aIter, &fd)) {
+      return false;
+    }
+    nativeHandle->data[i] = fd.fd;
+    nativeHandle->numFds = i + 1; // set number of valid file descriptors
+  }
+
+  GonkNativeHandle handle(new GonkNativeHandle::NhObj(nativeHandle.get()));
+  handle.TransferToAnother(*aResult);
+
+  mozilla::Unused << nativeHandle.release();
+
+  return true;
+}
+
+} // namespace IPC