ppapi: PPB_VpnProvider: Implement Resource Stub

ppapi/shared_impl/vpn_provider_util.cc

+// Copyright 2016 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 "ppapi/shared_impl/vpn_provider_util.h"
+
+namespace ppapi {
+
+VpnProviderSharedBuffer::VpnProviderSharedBuffer(
+    uint32_t capacity,
+    uint32_t packet_size,
+    std::unique_ptr<base::SharedMemory> shm)
+    : capacity_(capacity),
+      packet_size_(packet_size),
+      shm_(std::move(shm)),
+      available_(capacity, true) {
+  DCHECK(this->shm_);
+}
+
+VpnProviderSharedBuffer::~VpnProviderSharedBuffer() {}
+
+bool VpnProviderSharedBuffer::GetAvailable(uint32_t* id) {
+  for (uint32_t i = 0; i < capacity_; i++) {
+    if (available_[i]) {
+      if (id) {
+        *id = i;
+      }
+      return true;
+    }
+  }
+  return false;
+}
+
+void VpnProviderSharedBuffer::SetAvailable(uint32_t id, bool value) {
+  if (id >= capacity_) {
+    NOTREACHED();
+    return;
+  }
+  available_[id] = value;
+}
+
+void* VpnProviderSharedBuffer::GetBuffer(uint32_t id) {
+  if (id >= capacity_) {
+    NOTREACHED();
+    return nullptr;
+  }
+  return reinterpret_cast<char*>(shm_->memory()) + packet_size_ * id;
+}
+
+base::SharedMemoryHandle VpnProviderSharedBuffer::GetHandle() {
+  return shm_->handle();
+}
+
+}  // namespace ppapi