1 /* 2 * copyright 2010, 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 #ifndef BCC_CONTEXTMANAGER_H 18 #define BCC_CONTEXTMANAGER_H 19 20 #include <Config.h> 21 22 #include <llvm/Support/Mutex.h> 23 24 #include <unistd.h> 25 #include <stddef.h> 26 27 28 namespace bcc { 29 30 class ContextManager { 31 public: 32 // Starting address of context slot address space 33 static char * const ContextFixedAddr; 34 35 // Number of the context slots 36 static size_t const ContextSlotCount = BCC_CONTEXT_SLOT_COUNT_; 37 38 // Context size 39 static size_t const ContextCodeSize = BCC_CONTEXT_CODE_SIZE_; 40 static size_t const ContextDataSize = BCC_CONTEXT_DATA_SIZE_; 41 static size_t const ContextSize = ContextCodeSize + ContextDataSize; 42 43 private: 44 // Context manager singleton 45 static ContextManager TheContextManager; 46 47 private: 48 // Mutex lock for context slot occupation table 49 mutable llvm::sys::Mutex mContextSlotOccupiedLock; 50 51 // Context slot occupation table 52 bool mContextSlotOccupied[ContextSlotCount]; 53 54 ContextManager(); 55 56 public: get()57 static ContextManager &get() { 58 return TheContextManager; 59 } 60 61 char *allocateContext(); 62 char *allocateContext(char *addr, int imageFd, off_t imageOffset); 63 void deallocateContext(char *addr); 64 65 bool isManagingContext(char *addr) const; 66 67 private: 68 static ssize_t getSlotIndexFromAddress(char *addr); 69 70 }; 71 72 } // namespace bcc 73 74 #endif // BCC_CONTEXTMANAGER_H 75