static int init_pid( const char *name ) { pid_t pid = 0; sscanf( name, "%u", ( unsigned * ) &pid ); { read_pid_file( pid, "status", cbstatus ); read_pid_file( pid, "cmdline", cbcmdline ); } return 0; }
int zbx_sigusr_send(int flags) { int ret = FAIL; char error[256]; #ifdef HAVE_SIGQUEUE pid_t pid; if (SUCCEED == read_pid_file(CONFIG_PID_FILE, &pid, error, sizeof(error))) { union sigval s; s.ZBX_SIVAL_INT = flags; if (-1 != sigqueue(pid, SIGUSR1, s)) { zbx_error("command sent successfully"); ret = SUCCEED; } else { zbx_snprintf(error, sizeof(error), "cannot send command to PID [%d]: %s", (int)pid, zbx_strerror(errno)); } } #else zbx_snprintf(error, sizeof(error), "operation is not supported on the given operating system"); #endif if (SUCCEED != ret) zbx_error("%s", error); return ret; }
/* * stop myself */ static void stop_me(void) { pid_t pid; pid = read_pid_file(); if (pid < 0) { pool_error("could not read pid file"); pool_shmem_exit(1); exit(1); } if (kill(pid, stop_sig) == -1) { pool_error("could not stop pid: %d. reason: %s", pid, strerror(errno)); pool_shmem_exit(1); exit(1); } fprintf(stderr, "stop request sent to pgpool. waiting for termination..."); while (kill(pid, 0) == 0) { fprintf(stderr, "."); sleep(1); } fprintf(stderr, "done.\n"); }
/* * pgpool main program */ int main(int argc, char **argv) { int opt; int i; int pid; int size; int retrycnt; int sys_retrycnt; myargc = argc; myargv = argv; snprintf(conf_file, sizeof(conf_file), "%s/%s", DEFAULT_CONFIGDIR, POOL_CONF_FILE_NAME); snprintf(pcp_conf_file, sizeof(pcp_conf_file), "%s/%s", DEFAULT_CONFIGDIR, PCP_PASSWD_FILE_NAME); snprintf(hba_file, sizeof(hba_file), "%s/%s", DEFAULT_CONFIGDIR, HBA_CONF_FILE_NAME); while ((opt = getopt(argc, argv, "a:cdf:F:hm:nv")) != -1) { switch (opt) { case 'a': /* specify hba configuration file */ if (!optarg) { usage(); exit(1); } strncpy(hba_file, optarg, sizeof(hba_file)); break; case 'c': /* clear cache option */ clear_cache = 1; break; case 'd': /* debug option */ debug = 1; break; case 'f': /* specify configuration file */ if (!optarg) { usage(); exit(1); } strncpy(conf_file, optarg, sizeof(conf_file)); break; case 'F': /* specify PCP password file */ if (!optarg) { usage(); exit(1); } strncpy(pcp_conf_file, optarg, sizeof(pcp_conf_file)); break; case 'h': usage(); exit(0); break; case 'm': /* stop mode */ if (!optarg) { usage(); exit(1); } if (*optarg == 's' || !strcmp("smart", optarg)) stop_sig = SIGTERM; /* smart shutdown */ else if (*optarg == 'f' || !strcmp("fast", optarg)) stop_sig = SIGINT; /* fast shutdown */ else if (*optarg == 'i' || !strcmp("immediate", optarg)) stop_sig = SIGQUIT; /* immediate shutdown */ else { usage(); exit(1); } break; case 'n': /* no detaching control ttys */ not_detach = 1; break; case 'v': show_version(); exit(0); default: usage(); exit(1); } } mypid = getpid(); if (pool_init_config()) exit(1); if (pool_get_config(conf_file, INIT_CONFIG)) { pool_error("Unable to get configuration. Exiting..."); exit(1); } if (pool_config->enable_pool_hba) load_hba(hba_file); /* * If a non-switch argument remains, then it should be either "reload" or "stop". */ if (optind == (argc - 1)) { if (!strcmp(argv[optind], "reload")) { pid_t pid; pid = read_pid_file(); if (pid < 0) { pool_error("could not read pid file"); pool_shmem_exit(1); exit(1); } if (kill(pid, SIGHUP) == -1) { pool_error("could not reload configuration file pid: %d. reason: %s", pid, strerror(errno)); pool_shmem_exit(1); exit(1); } pool_shmem_exit(0); exit(0); } if (!strcmp(argv[optind], "stop")) { stop_me(); pool_shmem_exit(0); exit(0); } else { usage(); pool_shmem_exit(1); exit(1); } } /* * else if no non-switch argument remains, then it should be a start request */ else if (optind == argc) { pid = read_pid_file(); if (pid > 0) { if (kill(pid, 0) == 0) { fprintf(stderr, "pid file found. is another pgpool(%d) is running?\n", pid); exit(1); } else fprintf(stderr, "pid file found but it seems bogus. Trying to start pgpool anyway...\n"); } } /* * otherwise an error... */ else { usage(); exit(1); } /* set signal masks */ poolinitmask(); if (not_detach) write_pid_file(); else daemonize(); if (pool_semaphore_create(MAX_NUM_SEMAPHORES)) { pool_error("Unable to create semaphores. Exiting..."); pool_shmem_exit(1); exit(1); } /* * Restore previous backend status if possible */ read_status_file(); /* clear cache */ if (clear_cache && pool_config->enable_query_cache && SYSDB_STATUS == CON_UP) { Interval interval[1]; interval[0].quantity = 0; interval[0].unit = second; pool_clear_cache_by_time(interval, 1); } /* set unix domain socket path */ snprintf(un_addr.sun_path, sizeof(un_addr.sun_path), "%s/.s.PGSQL.%d", pool_config->socket_dir, pool_config->port); /* set up signal handlers */ pool_signal(SIGPIPE, SIG_IGN); /* create unix domain socket */ unix_fd = create_unix_domain_socket(un_addr); /* create inet domain socket if any */ if (pool_config->listen_addresses[0]) { inet_fd = create_inet_domain_socket(pool_config->listen_addresses, pool_config->port); } size = pool_config->num_init_children * pool_config->max_pool * sizeof(ConnectionInfo); con_info = pool_shared_memory_create(size); if (con_info == NULL) { pool_error("failed to allocate connection informations"); myexit(1); } memset(con_info, 0, size); size = pool_config->num_init_children * (sizeof(ProcessInfo)); pids = pool_shared_memory_create(size); if (pids == NULL) { pool_error("failed to allocate pids"); myexit(1); } memset(pids, 0, size); for (i = 0; i < pool_config->num_init_children; i++) { pids[i].connection_info = &con_info[i * pool_config->max_pool]; } /* create fail over/switch over event area */ Req_info = pool_shared_memory_create(sizeof(POOL_REQUEST_INFO)); if (Req_info == NULL) { pool_error("failed to allocate Req_info"); myexit(1); } /* initialize Req_info */ Req_info->kind = NODE_UP_REQUEST; memset(Req_info->node_id, -1, sizeof(int) * MAX_NUM_BACKENDS); Req_info->master_node_id = get_next_master_node(); Req_info->conn_counter = 0; InRecovery = pool_shared_memory_create(sizeof(int)); if (InRecovery == NULL) { pool_error("failed to allocate InRecovery"); myexit(1); } *InRecovery = 0; /* * We need to block signal here. Otherwise child might send some * signals, for example SIGUSR1(fail over). Children will inherit * signal blocking but they do unblock signals at the very beginning * of process. So this is harmless. */ POOL_SETMASK(&BlockSig); /* fork the children */ for (i=0;i<pool_config->num_init_children;i++) { pids[i].pid = fork_a_child(unix_fd, inet_fd, i); pids[i].start_time = time(NULL); } /* set up signal handlers */ pool_signal(SIGTERM, exit_handler); pool_signal(SIGINT, exit_handler); pool_signal(SIGQUIT, exit_handler); pool_signal(SIGCHLD, reap_handler); pool_signal(SIGUSR1, failover_handler); pool_signal(SIGUSR2, wakeup_handler); pool_signal(SIGHUP, reload_config_handler); /* create pipe for delivering event */ if (pipe(pipe_fds) < 0) { pool_error("failed to create pipe"); myexit(1); } pool_log("pgpool successfully started"); /* fork a child for PCP handling */ snprintf(pcp_un_addr.sun_path, sizeof(pcp_un_addr.sun_path), "%s/.s.PGSQL.%d", pool_config->pcp_socket_dir, pool_config->pcp_port); pcp_unix_fd = create_unix_domain_socket(pcp_un_addr); /* maybe change "*" to pool_config->pcp_listen_addresses */ pcp_inet_fd = create_inet_domain_socket("*", pool_config->pcp_port); pcp_pid = pcp_fork_a_child(pcp_unix_fd, pcp_inet_fd, pcp_conf_file); retrycnt = 0; /* reset health check retry counter */ sys_retrycnt = 0; /* reset SystemDB health check retry counter */ /* * This is the main loop */ for (;;) { CHECK_REQUEST; /* do we need health checking for PostgreSQL? */ if (pool_config->health_check_period > 0) { int sts; int sys_sts = 0; unsigned int sleep_time; if (retrycnt == 0) { pool_debug("starting health checking"); } else { pool_debug("retrying %d th health checking", retrycnt); } if (pool_config->health_check_timeout > 0) { /* * set health checker timeout. we want to detect * communication path failure much earlier before * TCP/IP stack detects it. */ pool_signal(SIGALRM, health_check_timer_handler); alarm(pool_config->health_check_timeout); } /* * do actual health check. trying to connect to the backend */ errno = 0; health_check_timer_expired = 0; POOL_SETMASK(&UnBlockSig); sts = health_check(); POOL_SETMASK(&BlockSig); if (pool_config->parallel_mode || pool_config->enable_query_cache) sys_sts = system_db_health_check(); if ((sts > 0 || sys_sts < 0) && (errno != EINTR || (errno == EINTR && health_check_timer_expired))) { if (sts > 0) { sts--; if (!pool_config->parallel_mode) { pool_log("set %d th backend down status", sts); Req_info->kind = NODE_DOWN_REQUEST; Req_info->node_id[0] = sts; failover(); /* need to distribute this info to children */ } else { retrycnt++; pool_signal(SIGALRM, SIG_IGN); /* Cancel timer */ if (retrycnt > NUM_BACKENDS) { /* retry count over */ pool_log("set %d th backend down status", sts); Req_info->kind = NODE_DOWN_REQUEST; Req_info->node_id[0] = sts; failover(); retrycnt = 0; } else { /* continue to retry */ sleep_time = pool_config->health_check_period/NUM_BACKENDS; pool_debug("retry sleep time: %d seconds", sleep_time); pool_sleep(sleep_time); continue; } } } if (sys_sts < 0) { sys_retrycnt++; pool_signal(SIGALRM, SIG_IGN); if (sys_retrycnt > NUM_BACKENDS) { pool_log("set SystemDB down status"); SYSDB_STATUS = CON_DOWN; sys_retrycnt = 0; } else if (sts == 0) /* goes to sleep only when SystemDB alone was down */ { sleep_time = pool_config->health_check_period/NUM_BACKENDS; pool_debug("retry sleep time: %d seconds", sleep_time); pool_sleep(sleep_time); continue; } } } if (pool_config->health_check_timeout > 0) { /* seems ok. cancel health check timer */ pool_signal(SIGALRM, SIG_IGN); } sleep_time = pool_config->health_check_period; pool_sleep(sleep_time); } else { for (;;) { int r; struct timeval t = {3, 0}; POOL_SETMASK(&UnBlockSig); r = pool_pause(&t); POOL_SETMASK(&BlockSig); if (r > 0) break; } } } pool_shmem_exit(0); }