1 files changed, 80 insertions, 0 deletions
diff --git a/security/sandbox/chromium/base/memory/unsafe_shared_memory_region.cc b/security/sandbox/chromium/base/memory/unsafe_shared_memory_region.cc
new file mode 100644
index 0000000000..92385d3e78
--- /dev/null
+++ b/security/sandbox/chromium/base/memory/unsafe_shared_memory_region.cc
@@ -0,0 +1,80 @@
+// Copyright 2018 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 "base/memory/unsafe_shared_memory_region.h"
+
+#include <utility>
+
+namespace base {
+
+UnsafeSharedMemoryRegion::CreateFunction*
+    UnsafeSharedMemoryRegion::create_hook_ = nullptr;
+
+// static
+UnsafeSharedMemoryRegion UnsafeSharedMemoryRegion::Create(size_t size) {
+  if (create_hook_)
+    return create_hook_(size);
+
+  subtle::PlatformSharedMemoryRegion handle =
+      subtle::PlatformSharedMemoryRegion::CreateUnsafe(size);
+
+  return UnsafeSharedMemoryRegion(std::move(handle));
+}
+
+// static
+UnsafeSharedMemoryRegion UnsafeSharedMemoryRegion::Deserialize(
+    subtle::PlatformSharedMemoryRegion handle) {
+  return UnsafeSharedMemoryRegion(std::move(handle));
+}
+
+// static
+subtle::PlatformSharedMemoryRegion
+UnsafeSharedMemoryRegion::TakeHandleForSerialization(
+    UnsafeSharedMemoryRegion region) {
+  return std::move(region.handle_);
+}
+
+UnsafeSharedMemoryRegion::UnsafeSharedMemoryRegion() = default;
+UnsafeSharedMemoryRegion::UnsafeSharedMemoryRegion(
+    UnsafeSharedMemoryRegion&& region) = default;
+UnsafeSharedMemoryRegion& UnsafeSharedMemoryRegion::operator=(
+    UnsafeSharedMemoryRegion&& region) = default;
+UnsafeSharedMemoryRegion::~UnsafeSharedMemoryRegion() = default;
+
+UnsafeSharedMemoryRegion UnsafeSharedMemoryRegion::Duplicate() const {
+  return UnsafeSharedMemoryRegion(handle_.Duplicate());
+}
+
+WritableSharedMemoryMapping UnsafeSharedMemoryRegion::Map() const {
+  return MapAt(0, handle_.GetSize());
+}
+
+WritableSharedMemoryMapping UnsafeSharedMemoryRegion::MapAt(off_t offset,
+                                                            size_t size) const {
+  if (!IsValid())
+    return {};
+
+  void* memory = nullptr;
+  size_t mapped_size = 0;
+  if (!handle_.MapAt(offset, size, &memory, &mapped_size))
+    return {};
+
+  return WritableSharedMemoryMapping(memory, size, mapped_size,
+                                     handle_.GetGUID());
+}
+
+bool UnsafeSharedMemoryRegion::IsValid() const {
+  return handle_.IsValid();
+}
+
+UnsafeSharedMemoryRegion::UnsafeSharedMemoryRegion(
+    subtle::PlatformSharedMemoryRegion handle)
+    : handle_(std::move(handle)) {
+  if (handle_.IsValid()) {
+    CHECK_EQ(handle_.GetMode(),
+             subtle::PlatformSharedMemoryRegion::Mode::kUnsafe);
+  }
+}
+
+}  // namespace base