/*
 * ep - extended pipelining
 *
 * sigserv.c - signal handling
 * ____________________________________________________________
 *
 * Developed by Ondrej Jombik <nepto@platon.sk>
 *          and Lubomir Host <rajo@platon.sk>
 * Copyright (c) 2000-2003 Platon SDG, http://platon.sk/
 * All rights reserved.
 *
 * See README file for more information about this software.
 * See COPYING file for license information.
 *
 * Download the latest version from
 * http://platon.sk/projects/ep/
 */

/* $Platon: ep/src/sigserv.c,v 1.13 2003/05/03 09:58:19 nepto Exp $ */

#ifdef HAVE_CONFIG_H
#  include "config.h"
#endif

#include <stdio.h>
#include <signal.h>
#include <errno.h>

#ifdef STDC_HEADERS
#  include <stdlib.h>
#  include <string.h>
#endif

#if HAVE_UNISTD_H
#  include <sys/types.h>
#  include <unistd.h>
#endif

#if HAVE_SYS_WAIT_H
#  include <sys/wait.h>
#endif


#include "sigserv.h"
#include "message.h"

#if DEBUG
static char *get_signal_str(int sig_no)
{
	char *s;

	switch (sig_no) {
		default: s = "unknown"; break;
		case SIGHUP: s = "SIGHUP"; break;
		case SIGINT: s = "SIGINT"; break;
		case SIGQUIT: s = "SIGQUIT"; break;
		case SIGILL: s = "SIGILL"; break;
		case SIGTRAP: s = "SIGTRAP"; break;
		case SIGABRT: s = "SIGABRT"; break;
					  /* case SIGIOT: s = "SIGIOT"; break; */
		case SIGBUS: s = "SIGBUS"; break;
		case SIGFPE: s = "SIGFPE"; break;
		case SIGKILL: s = "SIGKILL"; break;
		case SIGUSR1: s = "SIGUSR1"; break;
		case SIGSEGV: s = "SIGSEGV"; break;
		case SIGUSR2: s = "SIGUSR2"; break;
		case SIGPIPE: s = "SIGPIPE"; break;
		case SIGALRM: s = "SIGALRM"; break;
		case SIGTERM: s = "SIGTERM"; break;
		case SIGSTKFLT: s = "SIGSTKFLT"; break;
						/* case SIGCLD: s = "SIGCLD"; break; */
		case SIGCHLD: s = "SIGCHLD"; break;
		case SIGCONT: s = "SIGCONT"; break;
		case SIGSTOP: s = "SIGSTOP"; break;
		case SIGTSTP: s = "SIGTSTP"; break;
		case SIGTTIN: s = "SIGTTIN"; break;
		case SIGTTOU: s = "SIGTTOU"; break;
		case SIGURG: s = "SIGURG"; break;
		case SIGXCPU: s = "SIGXCPU"; break;
		case SIGXFSZ: s = "SIGXFSZ"; break;
		case SIGVTALRM: s = "SIGVTALRM"; break;
		case SIGPROF: s = "SIGPROF"; break;
		case SIGWINCH: s = "SIGWINCH"; break;
		case SIGPOLL: s = "SIGPOLL"; break;
					  /* case SIGIO: s = "SIGIO"; break; */
		case SIGPWR: s = "SIGPWR"; break;
		case SIGSYS: s = "SIGSYS"; break;
	}

	return s;
}

static char *get_signal_description(int sig_no)
{
	char *s;

	switch (sig_no) {
		default: s = "unknown"; break;
		case SIGHUP: s = "Hangup (POSIX)"; break;
		case SIGINT: s = "Interrupt (ANSI)"; break;
		case SIGQUIT: s = "Quit (POSIX)"; break;
		case SIGILL: s = "Illegal instruction (ANSI)"; break;
		case SIGTRAP: s = "Trace trap (POSIX)"; break;
		case SIGABRT: s = "Abort (ANSI)"; break;
					  /* case SIGIOT: s = "IOT trap (4.2 BSD)"; break; */
		case SIGBUS: s = "BUS error (4.2 BSD)"; break;
		case SIGFPE: s = "Floating-point exception (ANSI)"; break;
		case SIGKILL: s = "Kill, unblockable (POSIX)"; break;
		case SIGUSR1: s = "User-defined signal 1 (POSIX)"; break;
		case SIGSEGV: s = "Segmentation violation (ANSI)"; break;
		case SIGUSR2: s = "User-defined signal 2 (POSIX)"; break;
		case SIGPIPE: s = "Broken pipe (POSIX)"; break;
		case SIGALRM: s = "Alarm clock (POSIX)"; break;
		case SIGTERM: s = "Termination (ANSI)"; break;
		case SIGSTKFLT: s = "Stack fault"; break;
						/* case SIGCLD: s = "Same as SIGCHLD (System V)"; break; */
		case SIGCHLD: s = "Child status has changed (POSIX)"; break;
		case SIGCONT: s = "Continue (POSIX)"; break;
		case SIGSTOP: s = "Stop, unblockable (POSIX)"; break;
		case SIGTSTP: s = "Keyboard stop (POSIX)"; break;
		case SIGTTIN: s = "Background read from tty (POSIX)"; break;
		case SIGTTOU: s = "Background write to tty (POSIX)"; break;
		case SIGURG: s = "Urgent condition on socket (4.2 BSD)"; break;
		case SIGXCPU: s = "CPU limit exceeded (4.2 BSD)"; break;
		case SIGXFSZ: s = "File size limit exceeded (4.2 BSD)"; break;
		case SIGVTALRM: s = "Virtual alarm clock (4.2 BSD)"; break;
		case SIGPROF: s = "Profiling alarm clock (4.2 BSD)"; break;
		case SIGWINCH: s = "Window size change (4.3 BSD, Sun)"; break;
		case SIGPOLL: s = "Pollable event occurred (System V)"; break;
					  /* case SIGIO: s = "I/O now possible (4.2 BSD)"; break; */
		case SIGPWR: s = "Power failure restart (System V)"; break;
		case SIGSYS: s = "Bad system call"; break;
	};

	return s;
}
#endif

	static RETSIGTYPE
sigserv_sigaction(sig, info, unused)
	int       sig;
	siginfo_t *info;
	void      *unused;
{

#if DEBUG
	msg_debug_print("sigserv_sigaction(): sig = %s [%s]\n",
			get_signal_str(sig), get_signal_description(sig));
#endif

	switch (sig) {
		case SIGCHLD:
			sig_chld = 1;
			break;
	};

#if 0
	return;

	switch (sig) {
		case SIGCHLD:
			{
				int who, status;

				who = wait(&status);
				if (who == -1) {
					switch (errno) {
						case ECHILD:
							msg_error_print("No child processes, exiting...\n");
							exit(0);
							break;
						default:
							break;
					}
				}
				switch (info->si_code) {
					case CLD_EXITED:	/* | child has exited            | */
						msg_print("SIGCHLD -- child %d exited "
								"with status %d (%s)\n",
								info->si_pid,
								info->si_errno,
								strerror(info->si_errno));
						break;
					case CLD_KILLED:	/* | child was killed            | */
						msg_print("SIGCHLD -- child %d was killed"
								"by signal %d (%s)\n",
								info->si_pid,
								info->si_signo,
								strerror(info->si_errno));
						break;
					case CLD_DUMPED:	/* | child terminated abnormally | */
						msg_print("SIGCHLD -- child %d terminated abnormaly"
								"by signal %d (%s)\n",
								info->si_pid,
								info->si_signo,
								strerror(info->si_errno));
						break;
					case CLD_TRAPPED:	/* | traced child has trapped    | */
						break;
					case CLD_STOPPED:	/* | child has stopped           | */
						break;
					case CLD_CONTINUED:	/* | stopped child has continued | */
						break;
				}

			}
			break;
		case SIGINT:
			msg_print("\nSIGINT received, sending all process SIGTERM...\n");
			kill(0, SIGTERM);
			break;
		default:
			break;
	}
#endif
}

	void
sigserv_init(ptbl)
	PROCTABLE ptbl;
{
	struct sigaction sa;

	memset(&sa, '\0', sizeof sa);
	sa.sa_sigaction = sigserv_sigaction;
	sa.sa_flags     = SA_RESTART | SA_SIGINFO;

	sigaction(SIGQUIT, &sa, NULL);
	sigaction(SIGILL, &sa, NULL);
	sigaction(SIGABRT, &sa, NULL);
	sigaction(SIGFPE, &sa, NULL);
	sigaction(SIGKILL, &sa, NULL);
	sigaction(SIGSEGV, &sa, NULL);
	sigaction(SIGPIPE, &sa, NULL);
	sigaction(SIGALRM, &sa, NULL);
	sigaction(SIGTERM, &sa, NULL);
	sigaction(SIGUSR1, &sa, NULL);
	sigaction(SIGUSR2, &sa, NULL);
	sigaction(SIGCHLD, &sa, NULL);
	sigaction(SIGCONT, &sa, NULL);
	sigaction(SIGSTOP, &sa, NULL);
	sigaction(SIGTSTP, &sa, NULL);
	sigaction(SIGTTIN, &sa, NULL);
	sigaction(SIGTTOU, &sa, NULL);
	sigaction(SIGBUS, &sa, NULL);
	sigaction(SIGPOLL, &sa, NULL);
	sigaction(SIGPROF, &sa, NULL);
	sigaction(SIGSYS, &sa, NULL);
	sigaction(SIGTRAP, &sa, NULL);
	sigaction(SIGURG, &sa, NULL);
	sigaction(SIGVTALRM, &sa, NULL);
	sigaction(SIGXCPU, &sa, NULL);
	sigaction(SIGXFSZ, &sa, NULL);
	sigaction(SIGIOT, &sa, NULL);
	sigaction(SIGSTKFLT, &sa, NULL);
	sigaction(SIGIO, &sa, NULL);
	sigaction(SIGCLD, &sa, NULL);
	sigaction(SIGPWR, &sa, NULL);
	sigaction(SIGWINCH, &sa, NULL);
	sigaction(SIGUNUSED, &sa, NULL);

#if DEBUG
	msg_debug_print("sigserv_init(): signal handles installed\n");
#endif

	sig_chld = 0;
}

#if 0 /* Signals.  */ /* Linux 2.4.17 /usr/include/bits/signum.h */
#define SIGHUP          1       /* Hangup (POSIX).  */
#define SIGINT          2       /* Interrupt (ANSI).  */
#define SIGQUIT         3       /* Quit (POSIX).  */
#define SIGILL          4       /* Illegal instruction (ANSI).  */
#define SIGTRAP         5       /* Trace trap (POSIX).  */
#define SIGABRT         6       /* Abort (ANSI).  */
#define SIGIOT          6       /* IOT trap (4.2 BSD).  */
#define SIGBUS          7       /* BUS error (4.2 BSD).  */
#define SIGFPE          8       /* Floating-point exception (ANSI).  */
#define SIGKILL         9       /* Kill, unblockable (POSIX).  */
#define SIGUSR1         10      /* User-defined signal 1 (POSIX).  */
#define SIGSEGV         11      /* Segmentation violation (ANSI).  */
#define SIGUSR2         12      /* User-defined signal 2 (POSIX).  */
#define SIGPIPE         13      /* Broken pipe (POSIX).  */
#define SIGALRM         14      /* Alarm clock (POSIX).  */
#define SIGTERM         15      /* Termination (ANSI).  */
#define SIGSTKFLT       16      /* Stack fault.  */
#define SIGCLD          SIGCHLD /* Same as SIGCHLD (System V).  */
#define SIGCHLD         17      /* Child status has changed (POSIX).  */
#define SIGCONT         18      /* Continue (POSIX).  */
#define SIGSTOP         19      /* Stop, unblockable (POSIX).  */
#define SIGTSTP         20      /* Keyboard stop (POSIX).  */
#define SIGTTIN         21      /* Background read from tty (POSIX).  */
#define SIGTTOU         22      /* Background write to tty (POSIX).  */
#define SIGURG          23      /* Urgent condition on socket (4.2 BSD).  */
#define SIGXCPU         24      /* CPU limit exceeded (4.2 BSD).  */
#define SIGXFSZ         25      /* File size limit exceeded (4.2 BSD).  */
#define SIGVTALRM       26      /* Virtual alarm clock (4.2 BSD).  */
#define SIGPROF         27      /* Profiling alarm clock (4.2 BSD).  */
#define SIGWINCH        28      /* Window size change (4.3 BSD, Sun).  */
#define SIGPOLL         SIGIO   /* Pollable event occurred (System V).  */
#define SIGIO           29      /* I/O now possible (4.2 BSD).  */
#define SIGPWR          30      /* Power failure restart (System V).  */
#define SIGSYS          31      /* Bad system call.  */
#define SIGUNUSED       31
#endif