1 /* 2 * Copyright (C) 2022 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include <mediautils/Library.h> 18 #include <mediautils/MediaUtilsDelayed.h> 19 #include "MediaUtilsDelayedLibrary.h" 20 21 #define LOG_TAG "MediaUtilsDelayed" 22 #include <utils/Log.h> 23 #include <memory> 24 25 namespace android::mediautils { 26 27 namespace { 28 // Specific implementation details for MediaUtils Delayed Library. 29 30 // The following use static Meyer's singleton caches instead of letting 31 // refcounted management as provided above. This is for speed. getDelayedLibrary()32std::shared_ptr<void> getDelayedLibrary() { 33 static std::shared_ptr<void> library = loadLibrary(MEDIAUTILS_DELAYED_LIBRARY_NAME); 34 return library; 35 } 36 37 // Get the delayed dispatch table. This is refcounted and keeps the underlying library alive. getDelayedDispatchTable()38std::shared_ptr<delayed_library::DelayedDispatchTable> getDelayedDispatchTable() { 39 static auto delayedDispatchTable = 40 getObjectFromLibrary<delayed_library::DelayedDispatchTable>( 41 MEDIAUTILS_DELAYED_DISPATCH_TABLE_SYMBOL_NAME, getDelayedLibrary()); 42 return delayedDispatchTable; 43 } 44 45 } // namespace 46 47 // Public implementations of methods here. 48 getCallStackStringForTid(pid_t tid)49std::string getCallStackStringForTid(pid_t tid) { 50 auto delayedDispatchTable = getDelayedDispatchTable(); 51 if (!delayedDispatchTable) return {}; // on failure, return empty string 52 return delayedDispatchTable->getCallStackStringForTid(tid); 53 } 54 55 } // android::mediautils 56