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/*
 * Mini kill implementation for busybox
 *
 * Copyright (C) 1995, 1996 by Bruce Perens <bruce@pixar.com>.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 */


#include "internal.h"
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <signal.h>
#include <ctype.h>
#include <sys/stat.h>
#include <unistd.h>

static const char* kill_usage = "kill [-signal] process-id [process-id ...]\n\n"
"Send a signal (default is SIGTERM) to the specified process(es).\n\n"
"Options:\n"
"\t-l\tList all signal names and numbers.\n\n";


struct signal_name {
    const char *name;
    int number;
};

const struct signal_name signames[] = {
    {"HUP", SIGHUP},
    {"INT", SIGINT},
    {"QUIT", SIGQUIT},
    {"ILL", SIGILL},
    {"TRAP", SIGTRAP},
    {"ABRT", SIGABRT},
#ifndef __alpha__
    {"IOT", SIGIOT},
#endif
#if defined(__sparc__) || defined(__alpha__)
    {"EMT", SIGEMT},
#else
    {"BUS", SIGBUS},
#endif
    {"FPE", SIGFPE},
    {"KILL", SIGKILL},
#if defined(__sparc__) || defined(__alpha__)
    {"BUS", SIGBUS},
#else
    {"USR1", SIGUSR1},
#endif
    {"SEGV", SIGSEGV},
#if defined(__sparc__) || defined(__alpha__)
    {"SYS", SIGSYS},
#else
    {"USR2", SIGUSR2},
#endif
    {"PIPE", SIGPIPE},
    {"ALRM", SIGALRM},
    {"TERM", SIGTERM},
#if defined(__sparc__) || defined(__alpha__)
    {"URG", SIGURG},
    {"STOP", SIGSTOP},
    {"TSTP", SIGTSTP},
    {"CONT", SIGCONT},
    {"CHLD", SIGCHLD},
    {"TTIN", SIGTTIN},
    {"TTOU", SIGTTOU},
    {"IO", SIGIO},
# ifndef __alpha__
    {"POLL", SIGIO},
# endif
    {"XCPU", SIGXCPU},
    {"XFSZ", SIGXFSZ},
    {"VTALRM", SIGVTALRM},
    {"PROF", SIGPROF},
    {"WINCH", SIGWINCH},
# ifdef __alpha__
    {"INFO", SIGINFO},
# else
    {"LOST", SIGLOST},
# endif
    {"USR1", SIGUSR1},
    {"USR2", SIGUSR2},
#else
    {"STKFLT", SIGSTKFLT},
    {"CHLD", SIGCHLD},
    {"CONT", SIGCONT},
    {"STOP", SIGSTOP},
    {"TSTP", SIGTSTP},
    {"TTIN", SIGTTIN},
    {"TTOU", SIGTTOU},
    {"URG", SIGURG},
    {"XCPU", SIGXCPU},
    {"XFSZ", SIGXFSZ},
    {"VTALRM", SIGVTALRM},
    {"PROF", SIGPROF},
    {"WINCH", SIGWINCH},
    {"IO", SIGIO},
    {"POLL", SIGPOLL},
    {"PWR", SIGPWR},
    {"UNUSED", SIGUNUSED},
#endif
    {0, 0}
};

extern int kill_main (int argc, char **argv)
{
    int sig = SIGTERM;
    
    argc--;
    argv++;
    /* Parse any options */
    if (argc < 1) 
	usage(kill_usage);

    while (argc > 0 && **argv == '-') {
	while (*++(*argv)) {
	    switch (**argv) {
	    case 'l': 
		{
		    int col=0;
		    const struct signal_name *s = signames;

		    while (s->name != 0) {
			col+=fprintf(stderr, "%2d) %-8s", s->number, (s++)->name);
			if (col>60) {
			    fprintf(stderr, "\n");
			    col=0;
			}
		    }
		    fprintf(stderr, "\n\n");
		    exit( TRUE);
		}
		break;
	    case '-':
		usage(kill_usage);
	    default:
		{
		    if (isdigit( **argv)) {
			sig = atoi (*argv);
			if (sig < 0 || sig >= NSIG)
			    goto end;
			else {
			    argc--;
			    argv++;
			    goto do_it_now;
			}
		    }
		    else {
			const struct signal_name *s = signames;
			while (s->name != 0) {
			    if (strcasecmp (s->name, *argv) == 0) {
				sig = s->number;
				argc--;
				argv++;
				goto do_it_now;
			    }
			    s++;
			}
			if (s->name == 0)
			    goto end;
		    }
		}
	    }
	argc--;
	argv++;
	}
    }

do_it_now:

    while (argc >= 1) {
        int pid;
	struct stat statbuf;
	char pidpath[20]="/proc/";
	
        if (! isdigit( **argv)) {
            fprintf(stderr, "bad PID: %s\n", *argv);
            exit( FALSE);
        }
        pid = atoi (*argv);
	snprintf(pidpath, 20, "/proc/%s/stat", *argv);
	if (stat( pidpath, &statbuf)!=0) {
            fprintf(stderr, "kill: (%d) - No such pid\n", pid);
            exit( FALSE);
	}
        if (kill (pid, sig) != 0) {
            perror (*argv);
            exit ( FALSE);
        }
	argv++;
    }
    exit ( TRUE);


end:
    fprintf(stderr, "bad signal name: %s\n", *argv);
    exit (TRUE);
}