upload android base code part6

android/system/libhidl/libhidlmemory/mapping.cpp

@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#define LOG_TAG "libhidlmemory"
+
+#include <map>
+#include <mutex>
+#include <string>
+
+#include <hidlmemory/mapping.h>
+
+#include <android-base/logging.h>
+#include <android/hidl/memory/1.0/IMapper.h>
+#include <hidl/HidlSupport.h>
+
+using android::sp;
+using android::hidl::memory::V1_0::IMemory;
+using android::hidl::memory::V1_0::IMapper;
+
+namespace android {
+namespace hardware {
+
+static std::map<std::string, sp<IMapper>> gMappersByName;
+static std::mutex gMutex;
+
+static inline sp<IMapper> getMapperService(const std::string& name) {
+    std::unique_lock<std::mutex> _lock(gMutex);
+    auto iter = gMappersByName.find(name);
+    if (iter != gMappersByName.end()) {
+        return iter->second;
+    }
+
+    sp<IMapper> mapper = IMapper::getService(name, true /* getStub */);
+    if (mapper != nullptr) {
+        gMappersByName[name] = mapper;
+    }
+    return mapper;
+}
+
+sp<IMemory> mapMemory(const hidl_memory& memory) {
+
+    sp<IMapper> mapper = getMapperService(memory.name());
+
+    if (mapper == nullptr) {
+        LOG(ERROR) << "Could not fetch mapper for " << memory.name() << " shared memory";
+        return nullptr;
+    }
+
+    if (mapper->isRemote()) {
+        LOG(ERROR) << "IMapper must be a passthrough service.";
+        return nullptr;
+    }
+
+    Return<sp<IMemory>> ret = mapper->mapMemory(memory);
+
+    if (!ret.isOk()) {
+        LOG(ERROR) << "hidl_memory map returned transport error.";
+        return nullptr;
+    }
+
+    return ret;
+}
+
+}  // namespace hardware
+}  // namespace android