signaltest.cc revision b9d6a55eb4eb5872739ed26ac535f0c6342e813b 
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
26static int signal_count;
27static 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
50static 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
70static struct sigaction oldaction;
71
72extern "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
84extern "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.
90char *p = nullptr;
91
92extern "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