/* * Copyright (C) 2010 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include <stdio.h> #include <signal.h> #include <setjmp.h> static sigjmp_buf sbuf; void handler(int sig) { printf("In handler()\n"); siglongjmp(sbuf, 99); printf("After calling siglongjmp, but you won't see me here.\n"); } void foo() { struct sigaction sact; sigset_t sset; printf("In foo()\n"); /* Setup signal handler for SIGUSR2 */ sigemptyset(&sact.sa_mask); sact.sa_flags = 0; sact.sa_handler = handler; sigaction(SIGUSR2, &sact, NULL); /* Unblock SIGUSR2 */ sigemptyset(&sset); sigaddset(&sset, SIGUSR2); sigprocmask(SIG_UNBLOCK, &sset, NULL); /* Action */ kill(getpid(), SIGUSR2); printf("After calling kill, but you won't see me here.\n"); } void bar() { printf("In bar()\n"); foo(); printf("After calling foo, but you won't see me here.\n"); } int main() { int code, ret; sigset_t sset; printf("In main()\n"); sigemptyset(&sset); sigaddset(&sset, SIGUSR1); sigaddset(&sset, SIGUSR2); sigprocmask(SIG_SETMASK, &sset, NULL); if ((code = sigsetjmp(sbuf, 1)) == 0) { bar(); ret = 0xDEADBEEF; } else { printf("siglongjmp() back to main, code = %d\n", code); /* Make sure SIGUSR2 still blocked */ sigprocmask(SIG_SETMASK, NULL, &sset); ret = sigismember(&sset, SIGUSR2)? 0 : -1; } printf("ret = %d\n", ret); return ret; }