1 //===- FuzzerShmem.h - shared memory interface ------------------*- C++ -* ===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // SharedMemoryRegion 10 //===----------------------------------------------------------------------===// 11 12 #ifndef LLVM_FUZZER_SHMEM_H 13 #define LLVM_FUZZER_SHMEM_H 14 15 #include <algorithm> 16 #include <cstring> 17 #include <string> 18 19 #include "FuzzerDefs.h" 20 21 namespace fuzzer { 22 23 class SharedMemoryRegion { 24 public: 25 bool Create(const char *Name); 26 bool Open(const char *Name); 27 bool Destroy(const char *Name); 28 uint8_t *GetData() { return Data; } 29 void PostServer() {Post(0);} 30 void WaitServer() {Wait(0);} 31 void PostClient() {Post(1);} 32 void WaitClient() {Wait(1);} 33 34 size_t WriteByteArray(const uint8_t *Bytes, size_t N) { 35 assert(N <= kShmemSize - sizeof(N)); 36 memcpy(GetData(), &N, sizeof(N)); 37 memcpy(GetData() + sizeof(N), Bytes, N); 38 assert(N == ReadByteArraySize()); 39 return N; 40 } 41 size_t ReadByteArraySize() { 42 size_t Res; 43 memcpy(&Res, GetData(), sizeof(Res)); 44 return Res; 45 } 46 uint8_t *GetByteArray() { return GetData() + sizeof(size_t); } 47 48 bool IsServer() const { return Data && IAmServer; } 49 bool IsClient() const { return Data && !IAmServer; } 50 51 private: 52 53 static const size_t kShmemSize = 1 << 22; 54 bool IAmServer; 55 std::string Path(const char *Name); 56 std::string SemName(const char *Name, int Idx); 57 void Post(int Idx); 58 void Wait(int Idx); 59 60 bool Map(int fd); 61 uint8_t *Data = nullptr; 62 void *Semaphore[2]; 63 }; 64 65 extern SharedMemoryRegion SMR; 66 67 } // namespace fuzzer 68 69 #endif // LLVM_FUZZER_SHMEM_H 70
