/* $NetBSD: kill.c,v 1.33 2022/05/16 10:53:14 kre Exp $ */

/*
 * 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. 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.
 */

#include <sys/cdefs.h>
#if !defined(lint) && !defined(SHELL)
__COPYRIGHT("@(#) Copyright (c) 1988, 1993, 1994\
 The Regents of the University of California.  All rights reserved.");
#endif /* not lint */

#ifndef lint
#if 0
static char sccsid[] = "@(#)kill.c      8.4 (Berkeley) 4/28/95";
#else
__RCSID("$NetBSD: kill.c,v 1.33 2022/05/16 10:53:14 kre Exp $");
#endif
#endif /* not lint */

#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <limits.h>
#include <inttypes.h>
#include <string.h>
#include <termios.h>
#include <unistd.h>
#include <locale.h>
#include <sys/ioctl.h>

#ifdef SHELL            /* sh (aka ash) builtin */
int killcmd(int, char *argv[]);
#define main killcmd
#include "../../bin/sh/bltin/bltin.h"
#endif /* SHELL */ 

__dead static void nosig(const char *);
void printsignals(FILE *, int);
static int signum(const char *);
static int processnum(const char *, pid_t *);
__dead static void usage(void);

int
main(int argc, char *argv[])
{
        int errors;
        int numsig;
        pid_t pid;
        const char *sn;

        setprogname(argv[0]);
        setlocale(LC_ALL, "");
        if (argc < 2)
                usage();

        numsig = SIGTERM;

        argc--, argv++;

        /*
         * Process exactly 1 option, if there is one.
         */
        if (argv[0][0] == '-') {
                switch (argv[0][1]) {
                case 'l':
                        if (argv[0][2] != '\0')
                                sn = argv[0] + 2;
                        else {
                                argc--; argv++;
                                sn = argv[0];
                        }
                        if (argc > 1)
                                usage();
                        if (argc == 1) {
                                if (isdigit((unsigned char)*sn) == 0)
                                        usage();
                                numsig = signum(sn);
                                if (numsig >= 128)
                                        numsig -= 128;
                                if (numsig == 0 || signalnext(numsig) == -1)
                                        nosig(sn);
                                sn = signalname(numsig);
                                if (sn == NULL)
                                        errx(EXIT_FAILURE,
                                           "unknown signal number: %d", numsig);
                                printf("%s\n", sn);
                                exit(0);
                        }
                        printsignals(stdout, 0);
                        exit(0);

                case 's':
                        if (argv[0][2] != '\0')
                                sn = argv[0] + 2;
                        else {
                                argc--, argv++;
                                if (argc < 1) {
                                        warnx(
                                            "option requires an argument -- s");
                                        usage();
                                }
                                sn = argv[0];
                        }
                        if (strcmp(sn, "0") == 0)
                                numsig = 0;
                        else if ((numsig = signalnumber(sn)) == 0) {
                                if (sn != argv[0])
                                        goto trysignal;
                                nosig(sn);
                        }
                        argc--, argv++;
                        break;

                case '-':
                        if (argv[0][2] == '\0') {
                                /* process this one again later */
                                break;
                        }
                        /* FALL THROUGH */
                case '\0':
                        usage();
                        break;

                default:
 trysignal:
                        sn = *argv + 1;
                        if (((numsig = signalnumber(sn)) == 0)) {
                                if (isdigit((unsigned char)*sn))
                                        numsig = signum(sn);
                                else
                                        nosig(sn);
                        }

                        if (numsig != 0 && signalnext(numsig) == -1)
                                nosig(sn);
                        argc--, argv++;
                        break;
                }
        }

        /* deal with the optional '--' end of options option */
        if (argc > 0 && strcmp(*argv, "--") == 0)
                argc--, argv++;

        if (argc == 0)
                usage();

        for (errors = 0; argc; argc--, argv++) {
#ifdef SHELL
                extern int getjobpgrp(const char *);

                if (*argv[0] == '%') {
                        pid = getjobpgrp(*argv);
                        if (pid == 0) {
                                warnx("bad job id: %s", *argv);
                                errors = 1;
                                continue;
                        }
                } else 
#endif
                        if (processnum(*argv, &pid) != 0) {
                                errors = 1;
                                continue;
                        }

                if (kill(pid, numsig) == -1) {
                        warn("%s %s", pid < -1 ? "pgrp" : "pid", *argv);
                        errors = 1;
                }
#ifdef SHELL
                /*
                 * Wakeup the process if it was suspended, so it can
                 * exit without an explicit 'fg'.
                 *      (kernel handles this for SIGKILL)
                 */
                if (numsig == SIGTERM || numsig == SIGHUP)
                        kill(pid, SIGCONT);
#endif
        }

        exit(errors);
        /* NOTREACHED */
}

static int
signum(const char *sn)
{
        intmax_t n;
        char *ep;

        n = strtoimax(sn, &ep, 10);

        /* check for correctly parsed number */
        if (*ep || n <= INT_MIN || n >= INT_MAX )
                errx(EXIT_FAILURE, "bad signal number: %s", sn);
                /* NOTREACHED */

        return (int)n;
}

static int
processnum(const char *s, pid_t *pid)
{
        intmax_t n;
        char *ep;

        errno = 0;
        n = strtoimax(s, &ep, 10);

        /* check for correctly parsed number */
        if (ep == s || *ep || n == INTMAX_MIN || n == INTMAX_MAX ||
            (pid_t)n != n || errno != 0) {
                warnx("bad process%s id: '%s'", (n < 0 ? " group" : ""), s);
                return -1;
        }

        *pid = (pid_t)n;
        return 0;
}

static void
nosig(const char *name)
{

        warnx("unknown signal %s; valid signals:", name);
        printsignals(stderr, 0);
        exit(1);
        /* NOTREACHED */
}

#ifndef SHELL
/*
 * Print the names of all the signals (neatly) to fp
 * "len" gives the number of chars already printed to
 * the current output line (in kill.c, always 0)
 */
void
printsignals(FILE *fp, int len)
{
        int sig;
        int nl, pad;
        const char *name;
        int termwidth = 80;
        int posix;

        posix = getenv("POSIXLY_CORRECT") != 0;
        if ((name = getenv("COLUMNS")) != 0)
                termwidth = atoi(name);
        else if (isatty(fileno(fp))) {
                struct winsize win;

                if (ioctl(fileno(fp), TIOCGWINSZ, &win) == 0 && win.ws_col > 0)
                        termwidth = win.ws_col;
        }

        pad = (len | 7) + 1 - len;
        if (posix && pad)
                pad = 1;

        for (sig = 0; (sig = signalnext(sig)) != 0; ) {
                name = signalname(sig);
                if (name == NULL)
                        continue;

                nl = strlen(name);

                if (len > 0 && nl + len + pad >= termwidth) {
                        fprintf(fp, "\n");
                        len = 0;
                        pad = 0;
                } else if (pad > 0 && len != 0)
                        fprintf(fp, "%*s", pad, "");
                else
                        pad = 0;

                len += nl + pad;
                pad = (nl | 7) + 1 - nl;
                if (posix && pad)
                        pad = 1;

                fprintf(fp, "%s", name);
        }
        if (len != 0)
                fprintf(fp, "\n");
}
#endif

static void
usage(void)
{
        const char *pn = getprogname();

        fprintf(stderr, "usage: %s [-s signal_name] pid ...\n"
                        "       %s -l [exit_status]\n"
                        "       %s -signal_name pid ...\n"
                        "       %s -signal_number pid ...\n",
            pn, pn, pn, pn);
        exit(1);
        /* NOTREACHED */
}