1 /* 2 * Copyright (C) 2014 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 <signal.h> 18 #include <stdio.h> 19 #include <stdlib.h> 20 #include <unistd.h> 21 22 #include "jni.h" 23 24 #include <sys/ucontext.h> 25 26 static int signal_count; 27 static const int kMaxSignal = 2; 28 29 #if defined(__i386__) || defined(__x86_64__) 30 #if defined(__APPLE__) 31 #define ucontext __darwin_ucontext 32 33 #if defined(__x86_64__) 34 // 64 bit mac build. 35 #define CTX_EIP uc_mcontext->__ss.__rip 36 #else 37 // 32 bit mac build. 38 #define CTX_EIP uc_mcontext->__ss.__eip 39 #endif 40 41 #elif defined(__x86_64__) 42 // 64 bit linux build. 43 #define CTX_EIP uc_mcontext.gregs[REG_RIP] 44 #else 45 // 32 bit linux build. 46 #define CTX_EIP uc_mcontext.gregs[REG_EIP] 47 #endif 48 #endif 49 50 static void signalhandler(int sig, siginfo_t* info, void* context) { 51 printf("signal caught\n"); 52 ++signal_count; 53 if (signal_count > kMaxSignal) { 54 abort(); 55 } 56 #if defined(__arm__) 57 struct ucontext *uc = reinterpret_cast<struct ucontext*>(context); 58 struct sigcontext *sc = reinterpret_cast<struct sigcontext*>(&uc->uc_mcontext); 59 sc->arm_pc += 2; // Skip instruction causing segv. 60 #elif defined(__aarch64__) 61 struct ucontext *uc = reinterpret_cast<struct ucontext*>(context); 62 struct sigcontext *sc = reinterpret_cast<struct sigcontext*>(&uc->uc_mcontext); 63 sc->pc += 4; // Skip instruction causing segv. 64 #elif defined(__i386__) || defined(__x86_64__) 65 struct ucontext *uc = reinterpret_cast<struct ucontext*>(context); 66 uc->CTX_EIP += 3; 67 #endif 68 } 69 70 static struct sigaction oldaction; 71 72 extern "C" JNIEXPORT void JNICALL Java_Main_initSignalTest(JNIEnv*, jclass) { 73 struct sigaction action; 74 action.sa_sigaction = signalhandler; 75 sigemptyset(&action.sa_mask); 76 action.sa_flags = SA_SIGINFO | SA_ONSTACK; 77 #if !defined(__APPLE__) && !defined(__mips__) 78 action.sa_restorer = nullptr; 79 #endif 80 81 sigaction(SIGSEGV, &action, &oldaction); 82 } 83 84 extern "C" JNIEXPORT void JNICALL Java_Main_terminateSignalTest(JNIEnv*, jclass) { 85 sigaction(SIGSEGV, &oldaction, nullptr); 86 } 87 88 // Prevent the compiler being a smart-alec and optimizing out the assignment 89 // to nullptr. 90 char *p = nullptr; 91 92 extern "C" JNIEXPORT jint JNICALL Java_Main_testSignal(JNIEnv*, jclass) { 93 #if defined(__arm__) || defined(__i386__) || defined(__x86_64__) || defined(__aarch64__) 94 // On supported architectures we cause a real SEGV. 95 *p = 'a'; 96 #else 97 // On other architectures we simulate SEGV. 98 kill(getpid(), SIGSEGV); 99 #endif 100 return 1234; 101 } 102 103
