/*
 * Copyright (c) 1988, 1993, 1994
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */
/*
 *  oct 5 1994 -- almost entirely re-written to allow for process names.
 *  modifications (c) salvatore valente <svalente@mit.edu>
 *  may be used / modified / distributed under the same terms as the original.
 *
 *  1999-02-22 Arkadiusz Miśkiewicz <misiek@pld.ORG.PL>
 *  - added Native Language Support
 *
 *  1999-11-13 aeb Accept signal numers 128+s.
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>		/* for isdigit() */
#include <unistd.h>
#include <signal.h>

#include "c.h"
#include "nls.h"
#include "closestream.h"
#include "procutils.h"
#include "strutils.h"
#include "ttyutils.h"
#include "xalloc.h"

struct signv {
	const char *name;
	int val;
} sys_signame[] = {
	/* POSIX signals */
	{ "HUP",	SIGHUP },	/* 1 */
	{ "INT",	SIGINT }, 	/* 2 */
	{ "QUIT",	SIGQUIT }, 	/* 3 */
	{ "ILL",	SIGILL }, 	/* 4 */
#ifdef SIGTRAP
	{ "TRAP",	SIGTRAP },	/* 5 */
#endif
	{ "ABRT",	SIGABRT }, 	/* 6 */
#ifdef SIGIOT
	{ "IOT",	SIGIOT }, 	/* 6, same as SIGABRT */
#endif
#ifdef SIGEMT
	{ "EMT",	SIGEMT }, 	/* 7 (mips,alpha,sparc*) */
#endif
#ifdef SIGBUS
	{ "BUS",	SIGBUS },	/* 7 (arm,i386,m68k,ppc), 10 (mips,alpha,sparc*) */
#endif
	{ "FPE",	SIGFPE }, 	/* 8 */
	{ "KILL",	SIGKILL }, 	/* 9 */
	{ "USR1",	SIGUSR1 }, 	/* 10 (arm,i386,m68k,ppc), 30 (alpha,sparc*), 16 (mips) */
	{ "SEGV",	SIGSEGV }, 	/* 11 */
	{ "USR2",	SIGUSR2 }, 	/* 12 (arm,i386,m68k,ppc), 31 (alpha,sparc*), 17 (mips) */
	{ "PIPE",	SIGPIPE }, 	/* 13 */
	{ "ALRM",	SIGALRM }, 	/* 14 */
	{ "TERM",	SIGTERM }, 	/* 15 */
#ifdef SIGSTKFLT
	{ "STKFLT",	SIGSTKFLT },	/* 16 (arm,i386,m68k,ppc) */
#endif
	{ "CHLD",	SIGCHLD }, 	/* 17 (arm,i386,m68k,ppc), 20 (alpha,sparc*), 18 (mips) */
#ifdef SIGCLD
	{ "CLD",	SIGCLD },	/* same as SIGCHLD (mips) */
#endif
	{ "CONT",	SIGCONT }, 	/* 18 (arm,i386,m68k,ppc), 19 (alpha,sparc*), 25 (mips) */
	{ "STOP",	SIGSTOP },	/* 19 (arm,i386,m68k,ppc), 17 (alpha,sparc*), 23 (mips) */
	{ "TSTP",	SIGTSTP },	/* 20 (arm,i386,m68k,ppc), 18 (alpha,sparc*), 24 (mips) */
	{ "TTIN",	SIGTTIN },	/* 21 (arm,i386,m68k,ppc,alpha,sparc*), 26 (mips) */
	{ "TTOU",	SIGTTOU },	/* 22 (arm,i386,m68k,ppc,alpha,sparc*), 27 (mips) */
#ifdef SIGURG
	{ "URG",	SIGURG },	/* 23 (arm,i386,m68k,ppc), 16 (alpha,sparc*), 21 (mips) */
#endif
#ifdef SIGXCPU
	{ "XCPU",	SIGXCPU },	/* 24 (arm,i386,m68k,ppc,alpha,sparc*), 30 (mips) */
#endif
#ifdef SIGXFSZ
	{ "XFSZ",	SIGXFSZ },	/* 25 (arm,i386,m68k,ppc,alpha,sparc*), 31 (mips) */
#endif
#ifdef SIGVTALRM
	{ "VTALRM",	SIGVTALRM },	/* 26 (arm,i386,m68k,ppc,alpha,sparc*), 28 (mips) */
#endif
#ifdef SIGPROF
	{ "PROF",	SIGPROF },	/* 27 (arm,i386,m68k,ppc,alpha,sparc*), 29 (mips) */
#endif
#ifdef SIGWINCH
	{ "WINCH",	SIGWINCH },	/* 28 (arm,i386,m68k,ppc,alpha,sparc*), 20 (mips) */
#endif
#ifdef SIGIO
	{ "IO",		SIGIO },	/* 29 (arm,i386,m68k,ppc), 23 (alpha,sparc*), 22 (mips) */
#endif
#ifdef SIGPOLL
	{ "POLL",	SIGPOLL },	/* same as SIGIO */
#endif
#ifdef SIGINFO
	{ "INFO",	SIGINFO },	/* 29 (alpha) */
#endif
#ifdef SIGLOST
	{ "LOST",	SIGLOST }, 	/* 29 (arm,i386,m68k,ppc,sparc*) */
#endif
#ifdef SIGPWR
	{ "PWR",	SIGPWR },	/* 30 (arm,i386,m68k,ppc), 29 (alpha,sparc*), 19 (mips) */
#endif
#ifdef SIGUNUSED
	{ "UNUSED",	SIGUNUSED },	/* 31 (arm,i386,m68k,ppc) */
#endif
#ifdef SIGSYS
	{ "SYS",	SIGSYS }, 	/* 31 (mips,alpha,sparc*) */
#endif
};

static int arg_to_signum (char *arg, int mask);
static void nosig (char *name);
static void printsig (int sig);
static void printsignals (FILE *fp, int pretty);
static int usage (int status);
static int kill_verbose (char *procname, int pid, int sig);

#ifdef HAVE_SIGQUEUE
static int use_sigval;
static union sigval sigdata;
#endif

int main (int argc, char *argv[])
{
    int errors, numsig, pid;
    char *ep, *arg;
    int do_pid, do_kill, check_all;

    setlocale(LC_ALL, "");
    bindtextdomain(PACKAGE, LOCALEDIR);
    textdomain(PACKAGE);
    atexit(close_stdout);

    numsig = SIGTERM;
    do_pid = (! strcmp (program_invocation_short_name, "pid")); 	/* Yecch */
    do_kill = 0;
    check_all = 0;

    /*  loop through the arguments.
	actually, -a is the only option can be used with other options.
	`kill' is basically a one-option-at-most program.  */
    for (argc--, argv++; argc > 0; argc--, argv++) {
	arg = *argv;
	if (*arg != '-') {
	    break;
	}
	if (! strcmp (arg, "--")) {
	    argc--, argv++;
	    break;
	}
	if (! strcmp (arg, "-v") || ! strcmp (arg, "-V") ||
	    ! strcmp (arg, "--version")) {
	    printf(UTIL_LINUX_VERSION);
	    return EXIT_SUCCESS;
	}
	if (! strcmp (arg, "-h") || ! strcmp (arg, "--help"))
	    return usage(EXIT_FAILURE);

	if (! strcmp (arg, "-a") || ! strcmp (arg, "--all")) {
	    check_all++;
	    continue;
	}
	if (! strcmp (arg, "-l") || ! strcmp (arg, "--list")) {
	    if (argc < 2) {
		printsignals (stdout, 0);
		return EXIT_SUCCESS;
	    }
	    if (argc > 2)
		return usage (EXIT_FAILURE);
	    /* argc == 2, accept "kill -l $?" */
	    arg = argv[1];
	    if ((numsig = arg_to_signum (arg, 1)) < 0)
		errx(EXIT_FAILURE, _("unknown signal: %s"), arg);
	    printsig (numsig);
	    return EXIT_SUCCESS;
	}
	/* for compatibility with procps kill(1) */
	if (! strncmp (arg, "--list=", 7) || ! strncmp (arg, "-l=", 3)) {
		char *p = strchr(arg, '=') + 1;
		if ((numsig = arg_to_signum(p, 1)) < 0)
			errx(EXIT_FAILURE, _("unknown signal: %s"), p);
		printsig (numsig);
		return EXIT_SUCCESS;
	}
	if (! strcmp (arg, "-L") || ! strcmp (arg, "--table")) {
	    printsignals (stdout, 1);
	    return EXIT_SUCCESS;
	}
	if (! strcmp (arg, "-p") || ! strcmp (arg, "--pid")) {
	    do_pid++;
	    if (do_kill)
		return usage (EXIT_FAILURE);
	    continue;
	}
	if (! strcmp (arg, "-s") || ! strcmp (arg, "--signal")) {
	    if (argc < 2) {
		return usage (EXIT_FAILURE);
	    }
	    do_kill++;
	    if (do_pid)
		return usage (EXIT_FAILURE);
	    argc--, argv++;
	    arg = *argv;
	    if ((numsig = arg_to_signum (arg, 0)) < 0) {
		nosig (arg);
		return EXIT_FAILURE;
	    }
	    continue;
	}
	if (! strcmp (arg, "-q") || ! strcmp (arg, "--queue")) {
	    if (argc < 2)
		return usage (EXIT_FAILURE);
	    argc--, argv++;
	    arg = *argv;
#ifdef HAVE_SIGQUEUE
	    sigdata.sival_int = strtos32_or_err(arg, _("invalid sigval argument"));
	    use_sigval = 1;
#endif
	    continue;
	}
	/*  `arg' begins with a dash but is not a known option.
	    so it's probably something like -HUP, or -1/-n
	    try to deal with it.
	    -n could be signal n, or pid -n (i.e. process group n).
	    In case of doubt POSIX tells us to assume a signal.
	    If a signal has been parsed, assume it's a pid, break */
	if (do_kill)
	  break;
	arg++;
	if ((numsig = arg_to_signum (arg, 0)) < 0) {
	    return usage (EXIT_FAILURE);
	}
	do_kill++;
	if (do_pid)
	    return usage (EXIT_FAILURE);
	continue;
    }

    if (! *argv) {
	return usage (EXIT_FAILURE);
    }
    if (do_pid) {
	numsig = -1;
    }

    /*  we're done with the options.
	the rest of the arguments should be process ids and names.
	kill them.  */
    for (errors = 0; (arg = *argv) != NULL; argv++) {
	pid = strtol (arg, &ep, 10);
	if (! *ep)
	    errors += kill_verbose (arg, pid, numsig);
	else  {
	    struct proc_processes *ps = proc_open_processes();
	    int ct = 0;

	    if (!ps)
	        continue;

	    if (!check_all)
		proc_processes_filter_by_uid(ps, getuid());

	    proc_processes_filter_by_name(ps, arg);

	    while (proc_next_pid(ps, &pid) == 0) {
		errors += kill_verbose(arg, pid, numsig);
		ct++;
	    }

	    if (!ct) {
		errors++;
		warnx (_("cannot find process \"%s\""), arg);
	    }
	    proc_close_processes(ps);
	}
    }
    if (errors != 0)
	errors = EXIT_FAILURE;
    return errors;
}

#ifdef SIGRTMIN
static int rtsig_to_signum(char *sig)
{
	int num, maxi = 0;
	char *ep = NULL;

	if (strncasecmp(sig, "min+", 4) == 0)
		sig += 4;
	else if (strncasecmp(sig, "max-", 4) == 0) {
		sig += 4;
		maxi = 1;
	}

	if (!isdigit(*sig))
		return -1;

	errno = 0;
	num = strtol(sig, &ep, 10);
	if (!ep || sig == ep || errno || num < 0)
		return -1;

	num = maxi ? SIGRTMAX - num : SIGRTMIN + num;

	if (num < SIGRTMIN || num > SIGRTMAX)
		return -1;

	return num;
}
#endif

static int signame_to_signum (char *sig)
{
    size_t n;

    if (! strncasecmp (sig, "sig", 3))
	sig += 3;

#ifdef SIGRTMIN
    /* RT signals */
    if (!strncasecmp(sig, "rt", 2))
	return rtsig_to_signum(sig + 2);
#endif
    /* Normal sugnals */
    for (n = 0; n < ARRAY_SIZE(sys_signame); n++) {
	if (! strcasecmp (sys_signame[n].name, sig))
	    return sys_signame[n].val;
    }
    return (-1);
}

static int arg_to_signum (char *arg, int maskbit)
{
    int numsig;
    char *ep;

    if (isdigit (*arg)) {
	numsig = strtol (arg, &ep, 10);
	if (numsig >= NSIG && maskbit && (numsig & 128) != 0)
	    numsig -= 128;
	if (*ep != 0 || numsig < 0 || numsig >= NSIG)
	    return (-1);
	return (numsig);
    }
    return signame_to_signum (arg);
}

static void nosig (char *name)
{
    warnx (_("unknown signal %s; valid signals:"), name);
    printsignals (stderr, 1);
}

static void printsig (int sig)
{
    size_t n;

    for (n = 0; n < ARRAY_SIZE(sys_signame); n++) {
	if (sys_signame[n].val == sig) {
	    printf ("%s\n", sys_signame[n].name);
	    return;
	}
    }
#ifdef SIGRTMIN
    if (sig >= SIGRTMIN && sig <= SIGRTMAX) {
	printf ("RT%d\n", sig - SIGRTMIN);
	return;
    }
#endif
    printf("%d\n", sig);
}

#define FIELD_WIDTH 11
static void pretty_print_signal(FILE *fp, size_t term_width, size_t *lpos,
				int signum, const char *name)
{
	if (term_width < (*lpos + FIELD_WIDTH)) {
	    fputc ('\n', fp);
	    *lpos = 0;
	}
	*lpos += FIELD_WIDTH;
	fprintf (fp, "%2d %-8s", signum, name);
}

static void printsignals (FILE *fp, int pretty)
{
    size_t n, lth, lpos = 0, width;

    if (!pretty) {
	for (n = 0; n < ARRAY_SIZE(sys_signame); n++) {
	    lth = 1+strlen(sys_signame[n].name);
	    if (lpos+lth > 72) {
		fputc ('\n', fp);
		lpos = 0;
	    } else if (lpos)
		fputc (' ', fp);
	    lpos += lth;
	    fputs (sys_signame[n].name, fp);
	}
#ifdef SIGRTMIN
	fputs (" RT<N> RTMIN+<N> RTMAX-<N>", fp);
#endif
	fputc ('\n', fp);
	return;
    }
    /* pretty print */
    width = get_terminal_width();
    if (width == 0)
	width = 72;
    else
	width -= 1;

    for (n = 0; n < ARRAY_SIZE(sys_signame); n++)
	    pretty_print_signal(fp, width, &lpos,
			    sys_signame[n].val, sys_signame[n].name);

#ifdef SIGRTMIN
    pretty_print_signal(fp, width, &lpos, SIGRTMIN, "RTMIN");
    pretty_print_signal(fp, width, &lpos, SIGRTMAX, "RTMAX");
#endif
    fputc ('\n', fp);
}

static int usage(int status)
{
	FILE *out = (status == 0 ? stdout : stderr);

	fputs(USAGE_HEADER, out);
	fprintf(out, _(" %s [options] <pid|name> [...]\n"), program_invocation_short_name);
	fputs(USAGE_OPTIONS, out);
	fputs(_(" -a, --all              do not restrict the name-to-pid conversion to processes\n"
		"                        with the same uid as the present process\n"), out);
	fputs(_(" -s, --signal <sig>     send specified signal\n"), out);
	fputs(_(" -q, --queue <sig>      use sigqueue(2) rather than kill(2)\n"), out);
	fputs(_(" -p, --pid              print pids without signaling them\n"), out);
	fputs(_(" -l, --list [=<signal>] list signal names, or convert one to a name\n"), out);
	fputs(_(" -L, --table            list signal names and numbers\n"), out);
	fputs(USAGE_SEPARATOR, out);
	fputs(USAGE_HELP, out);
	fputs(USAGE_VERSION, out);
	fprintf(out, USAGE_MAN_TAIL("kill(1)"));

	return status;
}

static int kill_verbose (char *procname, pid_t pid, int sig)
{
    int rc = 0;

    if (sig < 0) {
	printf ("%ld\n", (long)pid);
	return 0;
    }
#ifdef HAVE_SIGQUEUE
    if (use_sigval)
	rc = sigqueue(pid, sig, sigdata);
    else
#endif
	rc = kill (pid, sig);

    if (rc < 0) {
	warn(_("sending signal to %s failed"), procname);
	return 1;
    }
    return 0;
}