diff options
Diffstat (limited to 'daemon/signals.c')
-rw-r--r-- | daemon/signals.c | 253 |
1 files changed, 0 insertions, 253 deletions
diff --git a/daemon/signals.c b/daemon/signals.c deleted file mode 100644 index 4f2254334..000000000 --- a/daemon/signals.c +++ /dev/null @@ -1,253 +0,0 @@ -// SPDX-License-Identifier: GPL-3.0-or-later - -#include "common.h" - -typedef enum signal_action { - NETDATA_SIGNAL_END_OF_LIST, - NETDATA_SIGNAL_IGNORE, - NETDATA_SIGNAL_EXIT_CLEANLY, - NETDATA_SIGNAL_SAVE_DATABASE, - NETDATA_SIGNAL_REOPEN_LOGS, - NETDATA_SIGNAL_RELOAD_HEALTH, - NETDATA_SIGNAL_FATAL, - NETDATA_SIGNAL_CHILD, -} SIGNAL_ACTION; - -static struct { - int signo; // the signal - const char *name; // the name of the signal - size_t count; // the number of signals received - SIGNAL_ACTION action; // the action to take -} signals_waiting[] = { - { SIGPIPE, "SIGPIPE", 0, NETDATA_SIGNAL_IGNORE }, - { SIGINT , "SIGINT", 0, NETDATA_SIGNAL_EXIT_CLEANLY }, - { SIGQUIT, "SIGQUIT", 0, NETDATA_SIGNAL_EXIT_CLEANLY }, - { SIGTERM, "SIGTERM", 0, NETDATA_SIGNAL_EXIT_CLEANLY }, - { SIGHUP, "SIGHUP", 0, NETDATA_SIGNAL_REOPEN_LOGS }, - { SIGUSR1, "SIGUSR1", 0, NETDATA_SIGNAL_SAVE_DATABASE }, - { SIGUSR2, "SIGUSR2", 0, NETDATA_SIGNAL_RELOAD_HEALTH }, - { SIGBUS, "SIGBUS", 0, NETDATA_SIGNAL_FATAL }, - { SIGCHLD, "SIGCHLD", 0, NETDATA_SIGNAL_CHILD }, - - // terminator - { 0, "NONE", 0, NETDATA_SIGNAL_END_OF_LIST } -}; - -static void signal_handler(int signo) { - // find the entry in the list - int i; - for(i = 0; signals_waiting[i].action != NETDATA_SIGNAL_END_OF_LIST ; i++) { - if(unlikely(signals_waiting[i].signo == signo)) { - signals_waiting[i].count++; - - if(signals_waiting[i].action == NETDATA_SIGNAL_FATAL) { - char buffer[200 + 1]; - snprintfz(buffer, sizeof(buffer) - 1, "\nSIGNAL HANDLER: received: %s. Oops! This is bad!\n", signals_waiting[i].name); - if(write(STDERR_FILENO, buffer, strlen(buffer)) == -1) { - // nothing to do - we cannot write but there is no way to complain about it - ; - } - } - - return; - } - } -} - -void signals_block(void) { - sigset_t sigset; - sigfillset(&sigset); - - if(pthread_sigmask(SIG_BLOCK, &sigset, NULL) == -1) - netdata_log_error("SIGNAL: Could not block signals for threads"); -} - -void signals_unblock(void) { - sigset_t sigset; - sigfillset(&sigset); - - if(pthread_sigmask(SIG_UNBLOCK, &sigset, NULL) == -1) { - netdata_log_error("SIGNAL: Could not unblock signals for threads"); - } -} - -void signals_init(void) { - // Catch signals which we want to use - struct sigaction sa; - sa.sa_flags = 0; - - // ignore all signals while we run in a signal handler - sigfillset(&sa.sa_mask); - - int i; - for (i = 0; signals_waiting[i].action != NETDATA_SIGNAL_END_OF_LIST; i++) { - switch (signals_waiting[i].action) { - case NETDATA_SIGNAL_IGNORE: - sa.sa_handler = SIG_IGN; - break; - default: - sa.sa_handler = signal_handler; - break; - } - - if(sigaction(signals_waiting[i].signo, &sa, NULL) == -1) - netdata_log_error("SIGNAL: Failed to change signal handler for: %s", signals_waiting[i].name); - } -} - -void signals_restore_SIGCHLD(void) -{ - struct sigaction sa; - - sa.sa_flags = 0; - sigfillset(&sa.sa_mask); - sa.sa_handler = signal_handler; - - if(sigaction(SIGCHLD, &sa, NULL) == -1) - netdata_log_error("SIGNAL: Failed to change signal handler for: SIGCHLD"); -} - -void signals_reset(void) { - struct sigaction sa; - sigemptyset(&sa.sa_mask); - sa.sa_handler = SIG_DFL; - sa.sa_flags = 0; - - int i; - for (i = 0; signals_waiting[i].action != NETDATA_SIGNAL_END_OF_LIST; i++) { - if(sigaction(signals_waiting[i].signo, &sa, NULL) == -1) - netdata_log_error("SIGNAL: Failed to reset signal handler for: %s", signals_waiting[i].name); - } -} - -// reap_child reaps the child identified by pid. -static void reap_child(pid_t pid) { - siginfo_t i; - - errno = 0; - netdata_log_debug(D_CHILDS, "SIGNAL: reap_child(%d)...", pid); - if (netdata_waitid(P_PID, (id_t)pid, &i, WEXITED|WNOHANG) == -1) { - if (errno != ECHILD) - netdata_log_error("SIGNAL: waitid(%d): failed to wait for child", pid); - else - netdata_log_info("SIGNAL: waitid(%d): failed - it seems the child is already reaped", pid); - return; - } - else if (i.si_pid == 0) { - // Process didn't exit, this shouldn't happen. - netdata_log_error("SIGNAL: waitid(%d): reports pid 0 - child has not exited", pid); - return; - } - - switch (i.si_code) { - case CLD_EXITED: - netdata_log_info("SIGNAL: reap_child(%d) exited with code: %d", pid, i.si_status); - break; - case CLD_KILLED: - netdata_log_info("SIGNAL: reap_child(%d) killed by signal: %d", pid, i.si_status); - break; - case CLD_DUMPED: - netdata_log_info("SIGNAL: reap_child(%d) dumped core by signal: %d", pid, i.si_status); - break; - case CLD_STOPPED: - netdata_log_info("SIGNAL: reap_child(%d) stopped by signal: %d", pid, i.si_status); - break; - case CLD_TRAPPED: - netdata_log_info("SIGNAL: reap_child(%d) trapped by signal: %d", pid, i.si_status); - break; - case CLD_CONTINUED: - netdata_log_info("SIGNAL: reap_child(%d) continued by signal: %d", pid, i.si_status); - break; - default: - netdata_log_info("SIGNAL: reap_child(%d) gave us a SIGCHLD with code %d and status %d.", pid, i.si_code, i.si_status); - break; - } -} - -// reap_children reaps all pending children which are not managed by myp. -static void reap_children() { - siginfo_t i; - - while(1) { - i.si_pid = 0; - if (netdata_waitid(P_ALL, (id_t)0, &i, WEXITED|WNOHANG|WNOWAIT) == -1 || i.si_pid == 0) - // nothing to do - return; - - reap_child(i.si_pid); - } -} - -void signals_handle(void) { - while(1) { - - // pause() causes the calling process (or thread) to sleep until a signal - // is delivered that either terminates the process or causes the invocation - // of a signal-catching function. - if(pause() == -1 && errno == EINTR) { - - // loop once, but keep looping while signals are coming in - // this is needed because a few operations may take some time - // so we need to check for new signals before pausing again - int found = 1; - while(found) { - found = 0; - - // execute the actions of the signals - int i; - for (i = 0; signals_waiting[i].action != NETDATA_SIGNAL_END_OF_LIST; i++) { - if (signals_waiting[i].count) { - found = 1; - signals_waiting[i].count = 0; - const char *name = signals_waiting[i].name; - - switch (signals_waiting[i].action) { - case NETDATA_SIGNAL_RELOAD_HEALTH: - nd_log_limits_unlimited(); - netdata_log_info("SIGNAL: Received %s. Reloading HEALTH configuration...", name); - nd_log_limits_reset(); - execute_command(CMD_RELOAD_HEALTH, NULL, NULL); - break; - - case NETDATA_SIGNAL_SAVE_DATABASE: - nd_log_limits_unlimited(); - netdata_log_info("SIGNAL: Received %s. Saving databases...", name); - nd_log_limits_reset(); - execute_command(CMD_SAVE_DATABASE, NULL, NULL); - break; - - case NETDATA_SIGNAL_REOPEN_LOGS: - nd_log_limits_unlimited(); - netdata_log_info("SIGNAL: Received %s. Reopening all log files...", name); - nd_log_limits_reset(); - execute_command(CMD_REOPEN_LOGS, NULL, NULL); - break; - - case NETDATA_SIGNAL_EXIT_CLEANLY: - nd_log_limits_unlimited(); - netdata_log_info("SIGNAL: Received %s. Cleaning up to exit...", name); - commands_exit(); - netdata_cleanup_and_exit(0); - exit(0); - break; - - case NETDATA_SIGNAL_FATAL: - fatal("SIGNAL: Received %s. netdata now exits.", name); - break; - - case NETDATA_SIGNAL_CHILD: - reap_children(); - break; - - default: - netdata_log_info("SIGNAL: Received %s. No signal handler configured. Ignoring it.", name); - break; - } - } - } - } - } - else - netdata_log_error("SIGNAL: pause() returned but it was not interrupted by a signal."); - } -} |