| /* |
| * 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 <errno.h> |
| #include <signal.h> |
| #include <unistd.h> |
| #include <fcntl.h> |
| #include <sys/types.h> |
| #include <sys/socket.h> |
| #include <sys/wait.h> |
| #include <cutils/sockets.h> |
| #include <cutils/android_reboot.h> |
| #include <cutils/list.h> |
| |
| #include "init.h" |
| #include "util.h" |
| #include "log.h" |
| |
| static int signal_fd = -1; |
| static int signal_recv_fd = -1; |
| |
| static void sigchld_handler(int s) |
| { |
| write(signal_fd, &s, 1); |
| } |
| |
| #define CRITICAL_CRASH_THRESHOLD 4 /* if we crash >4 times ... */ |
| #define CRITICAL_CRASH_WINDOW (4*60) /* ... in 4 minutes, goto recovery*/ |
| |
| static int wait_for_one_process(int block) |
| { |
| pid_t pid; |
| int status; |
| struct service *svc; |
| struct socketinfo *si; |
| time_t now; |
| struct listnode *node; |
| struct command *cmd; |
| |
| while ( (pid = waitpid(-1, &status, block ? 0 : WNOHANG)) == -1 && errno == EINTR ); |
| if (pid <= 0) return -1; |
| INFO("waitpid returned pid %d, status = %08x\n", pid, status); |
| |
| svc = service_find_by_pid(pid); |
| if (!svc) { |
| if (WIFEXITED(status)) { |
| ERROR("untracked pid %d exited with status %d\n", pid, WEXITSTATUS(status)); |
| } else if (WIFSIGNALED(status)) { |
| ERROR("untracked pid %d killed by signal %d\n", pid, WTERMSIG(status)); |
| } else if (WIFSTOPPED(status)) { |
| ERROR("untracked pid %d stopped by signal %d\n", pid, WSTOPSIG(status)); |
| } else { |
| ERROR("untracked pid %d state changed\n", pid); |
| } |
| return 0; |
| } |
| |
| NOTICE("process '%s', pid %d exited\n", svc->name, pid); |
| |
| if (!(svc->flags & SVC_ONESHOT) || (svc->flags & SVC_RESTART)) { |
| kill(-pid, SIGKILL); |
| NOTICE("process '%s' killing any children in process group\n", svc->name); |
| } |
| |
| /* remove any sockets we may have created */ |
| for (si = svc->sockets; si; si = si->next) { |
| char tmp[128]; |
| snprintf(tmp, sizeof(tmp), ANDROID_SOCKET_DIR"/%s", si->name); |
| unlink(tmp); |
| } |
| |
| svc->pid = 0; |
| svc->flags &= (~SVC_RUNNING); |
| |
| /* oneshot processes go into the disabled state on exit, |
| * except when manually restarted. */ |
| if ((svc->flags & SVC_ONESHOT) && !(svc->flags & SVC_RESTART)) { |
| svc->flags |= SVC_DISABLED; |
| } |
| |
| /* disabled and reset processes do not get restarted automatically */ |
| if (svc->flags & (SVC_DISABLED | SVC_RESET) ) { |
| notify_service_state(svc->name, "stopped"); |
| return 0; |
| } |
| |
| now = gettime(); |
| if ((svc->flags & SVC_CRITICAL) && !(svc->flags & SVC_RESTART)) { |
| if (svc->time_crashed + CRITICAL_CRASH_WINDOW >= now) { |
| if (++svc->nr_crashed > CRITICAL_CRASH_THRESHOLD) { |
| ERROR("critical process '%s' exited %d times in %d minutes; " |
| "rebooting into recovery mode\n", svc->name, |
| CRITICAL_CRASH_THRESHOLD, CRITICAL_CRASH_WINDOW / 60); |
| android_reboot(ANDROID_RB_RESTART2, 0, "recovery"); |
| return 0; |
| } |
| } else { |
| svc->time_crashed = now; |
| svc->nr_crashed = 1; |
| } |
| } |
| |
| svc->flags &= (~SVC_RESTART); |
| svc->flags |= SVC_RESTARTING; |
| |
| /* Execute all onrestart commands for this service. */ |
| list_for_each(node, &svc->onrestart.commands) { |
| cmd = node_to_item(node, struct command, clist); |
| cmd->func(cmd->nargs, cmd->args); |
| } |
| notify_service_state(svc->name, "restarting"); |
| return 0; |
| } |
| |
| void handle_signal(void) |
| { |
| char tmp[32]; |
| |
| /* we got a SIGCHLD - reap and restart as needed */ |
| read(signal_recv_fd, tmp, sizeof(tmp)); |
| while (!wait_for_one_process(0)) |
| ; |
| } |
| |
| void signal_init(void) |
| { |
| int s[2]; |
| |
| struct sigaction act; |
| memset(&act, 0, sizeof(act)); |
| act.sa_handler = sigchld_handler; |
| act.sa_flags = SA_NOCLDSTOP; |
| sigaction(SIGCHLD, &act, 0); |
| |
| /* create a signalling mechanism for the sigchld handler */ |
| if (socketpair(AF_UNIX, SOCK_STREAM | SOCK_NONBLOCK | SOCK_CLOEXEC, 0, s) == 0) { |
| signal_fd = s[0]; |
| signal_recv_fd = s[1]; |
| } |
| |
| handle_signal(); |
| } |
| |
| int get_signal_fd() |
| { |
| return signal_recv_fd; |
| } |