/*
- * Copyright (C) 2004-2009 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2004-2010 Andre Noll <maan@systemlinux.org>
*
* Licensed under the GPL v2. For licencing details see COPYING.
*/
}
/**
- * Paraslash's zombie killer.
+ * Install the given handler for the given signal.
*
- * It just calls \p para_reap_child() until there are no more children left to
- * reap.
+ * \param sig The number of the signal to catch.
+ * \param handler to be installed, \p SIG_IGN, or \p SIG_DFL.
+ *
+ * This either succeeds or calls exit(EXIT_FAILURE).
+ *
+ * \sa sigaction(2).
*/
-void para_reap_children(void)
+void para_sigaction(int sig, void (*handler)(int))
{
- pid_t pid;
+ struct sigaction act;
- while (para_reap_child(&pid) > 0)
- ; /* nothing */
+ PARA_DEBUG_LOG("catching signal %d\n", sig);
+ act.sa_handler = handler;
+ sigemptyset(&act.sa_mask);
+ act.sa_flags = 0;
+ if (sig == SIGALRM) {
+ #ifdef SA_INTERRUPT /* SunOS */
+ act.sa_flags |= SA_INTERRUPT;
+ #endif
+ } else {
+ #ifdef SA_RESTART /* BSD */
+ act.sa_flags |= SA_RESTART;
+ #endif
+ }
+ if (sigaction(sig, &act, NULL) >= 0)
+ return;
+ PARA_EMERG_LOG("failed to install signal handler for signal %d\n",
+ sig);
+ exit(EXIT_FAILURE);
}
/**
- * Wrapper around signal(2).
+ * Install the generic signal handler for the given signal number.
*
* \param sig The number of the signal to catch.
*
- * This installs the generic signal handler for the given signal.
- *
- * \return This function returns 1 on success and \p -E_SIGNAL_SIG_ERR on errors.
- *
- * \sa signal(2).
+ * \sa signal(2), sigaction(2).
*/
-int para_install_sighandler(int sig)
+void para_install_sighandler(int sig)
{
- PARA_DEBUG_LOG("catching signal %d\n", sig);
- return signal(sig, &generic_signal_handler) == SIG_ERR? -E_SIGNAL_SIG_ERR : 1;
+ para_sigaction(sig, &generic_signal_handler);
}
/**
- * Return the number of next pending signal.
+ * Return the number of the next pending signal.
*
- * This should be called if the fd for the signal pipe is ready for reading.
+ * \param rfds Th fd_set containing the signal pipe.
*
- * \return On success, the number of the received signal is returned. If the
- * read returned zero or was interrupted by another signal the function returns
- * 0. Otherwise, a negative error value is returned.
+ * \return On success, the number of the received signal is returned. If there
+ * is no signal currently pending, the function returns zero. On read errors
+ * from the signal pipe, the process is terminated.
*/
-int para_next_signal(void)
+int para_next_signal(fd_set *rfds)
{
- int s;
- ssize_t r = read(signal_pipe[0], &s, sizeof(s));
+ size_t n;
+ int s, ret = read_nonblock(signal_pipe[0], &s, sizeof(s), rfds, &n);
- if (!r) {
- PARA_CRIT_LOG("read from signal pipe returned zero\n");
- return 0;
+ if (ret < 0) {
+ PARA_EMERG_LOG("%s\n", para_strerror(-ret));
+ exit(EXIT_FAILURE);
}
- if (r < 0) {
- if (errno == EAGAIN || errno == EINTR)
- return 0;
- return -ERRNO_TO_PARA_ERROR(errno);
- }
- assert(r == sizeof(s));
+ if (n == 0)
+ return 0;
+ assert(n == sizeof(s));
PARA_DEBUG_LOG("next signal: %d\n", s);
return s;
}