1/* $NetBSD: kill.c,v 1.33 2022/05/16 10:53:14 kre Exp $ */
2
3/*
4 * Copyright (c) 1988, 1993, 1994
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32#include <sys/cdefs.h>
33#if !defined(lint) && !defined(SHELL)
34__COPYRIGHT("@(#) Copyright (c) 1988, 1993, 1994\
35 The Regents of the University of California.  All rights reserved.");
36#endif /* not lint */
37
38#ifndef lint
39#if 0
40static char sccsid[] = "@(#)kill.c	8.4 (Berkeley) 4/28/95";
41#else
42__RCSID("$NetBSD: kill.c,v 1.33 2022/05/16 10:53:14 kre Exp $");
43#endif
44#endif /* not lint */
45
46#include <ctype.h>
47#include <err.h>
48#include <errno.h>
49#include <signal.h>
50#include <stdio.h>
51#include <stdlib.h>
52#include <limits.h>
53#include <inttypes.h>
54#include <string.h>
55#include <termios.h>
56#include <unistd.h>
57#include <locale.h>
58#include <sys/ioctl.h>
59
60#ifdef SHELL            /* sh (aka ash) builtin */
61int killcmd(int, char *argv[]);
62#define main killcmd
63#include "../../bin/sh/bltin/bltin.h"
64#endif /* SHELL */
65
66__dead static void nosig(const char *);
67void printsignals(FILE *, int);
68static int signum(const char *);
69static int processnum(const char *, pid_t *);
70__dead static void usage(void);
71
72int
73main(int argc, char *argv[])
74{
75	int errors;
76	int numsig;
77	pid_t pid;
78	const char *sn;
79
80	setprogname(argv[0]);
81	setlocale(LC_ALL, "");
82	if (argc < 2)
83		usage();
84
85	numsig = SIGTERM;
86
87	argc--, argv++;
88
89	/*
90	 * Process exactly 1 option, if there is one.
91	 */
92	if (argv[0][0] == '-') {
93		switch (argv[0][1]) {
94		case 'l':
95			if (argv[0][2] != '\0')
96				sn = argv[0] + 2;
97			else {
98				argc--; argv++;
99				sn = argv[0];
100			}
101			if (argc > 1)
102				usage();
103			if (argc == 1) {
104				if (isdigit((unsigned char)*sn) == 0)
105					usage();
106				numsig = signum(sn);
107				if (numsig >= 128)
108					numsig -= 128;
109				if (numsig == 0 || signalnext(numsig) == -1)
110					nosig(sn);
111				sn = signalname(numsig);
112				if (sn == NULL)
113					errx(EXIT_FAILURE,
114					   "unknown signal number: %d", numsig);
115				printf("%s\n", sn);
116				exit(0);
117			}
118			printsignals(stdout, 0);
119			exit(0);
120
121		case 's':
122			if (argv[0][2] != '\0')
123				sn = argv[0] + 2;
124			else {
125				argc--, argv++;
126				if (argc < 1) {
127					warnx(
128					    "option requires an argument -- s");
129					usage();
130				}
131				sn = argv[0];
132			}
133			if (strcmp(sn, "0") == 0)
134				numsig = 0;
135			else if ((numsig = signalnumber(sn)) == 0) {
136				if (sn != argv[0])
137					goto trysignal;
138				nosig(sn);
139			}
140			argc--, argv++;
141			break;
142
143		case '-':
144			if (argv[0][2] == '\0') {
145				/* process this one again later */
146				break;
147			}
148			/* FALL THROUGH */
149		case '\0':
150			usage();
151			break;
152
153		default:
154 trysignal:
155			sn = *argv + 1;
156			if (((numsig = signalnumber(sn)) == 0)) {
157				if (isdigit((unsigned char)*sn))
158					numsig = signum(sn);
159				else
160					nosig(sn);
161			}
162
163			if (numsig != 0 && signalnext(numsig) == -1)
164				nosig(sn);
165			argc--, argv++;
166			break;
167		}
168	}
169
170	/* deal with the optional '--' end of options option */
171	if (argc > 0 && strcmp(*argv, "--") == 0)
172		argc--, argv++;
173
174	if (argc == 0)
175		usage();
176
177	for (errors = 0; argc; argc--, argv++) {
178#ifdef SHELL
179		extern int getjobpgrp(const char *);
180
181		if (*argv[0] == '%') {
182			pid = getjobpgrp(*argv);
183			if (pid == 0) {
184				warnx("bad job id: %s", *argv);
185				errors = 1;
186				continue;
187			}
188		} else
189#endif
190			if (processnum(*argv, &pid) != 0) {
191				errors = 1;
192				continue;
193			}
194
195		if (kill(pid, numsig) == -1) {
196			warn("%s %s", pid < -1 ? "pgrp" : "pid", *argv);
197			errors = 1;
198		}
199#ifdef SHELL
200		/*
201		 * Wakeup the process if it was suspended, so it can
202		 * exit without an explicit 'fg'.
203		 *	(kernel handles this for SIGKILL)
204		 */
205		if (numsig == SIGTERM || numsig == SIGHUP)
206			kill(pid, SIGCONT);
207#endif
208	}
209
210	exit(errors);
211	/* NOTREACHED */
212}
213
214static int
215signum(const char *sn)
216{
217	intmax_t n;
218	char *ep;
219
220	n = strtoimax(sn, &ep, 10);
221
222	/* check for correctly parsed number */
223	if (*ep || n <= INT_MIN || n >= INT_MAX )
224		errx(EXIT_FAILURE, "bad signal number: %s", sn);
225		/* NOTREACHED */
226
227	return (int)n;
228}
229
230static int
231processnum(const char *s, pid_t *pid)
232{
233	intmax_t n;
234	char *ep;
235
236	errno = 0;
237	n = strtoimax(s, &ep, 10);
238
239	/* check for correctly parsed number */
240	if (ep == s || *ep || n == INTMAX_MIN || n == INTMAX_MAX ||
241	    (pid_t)n != n || errno != 0) {
242		warnx("bad process%s id: '%s'", (n < 0 ? " group" : ""), s);
243		return -1;
244	}
245
246	*pid = (pid_t)n;
247	return 0;
248}
249
250static void
251nosig(const char *name)
252{
253
254	warnx("unknown signal %s; valid signals:", name);
255	printsignals(stderr, 0);
256	exit(1);
257	/* NOTREACHED */
258}
259
260#ifndef SHELL
261/*
262 * Print the names of all the signals (neatly) to fp
263 * "len" gives the number of chars already printed to
264 * the current output line (in kill.c, always 0)
265 */
266void
267printsignals(FILE *fp, int len)
268{
269	int sig;
270	int nl, pad;
271	const char *name;
272	int termwidth = 80;
273	int posix;
274
275	posix = getenv("POSIXLY_CORRECT") != 0;
276	if ((name = getenv("COLUMNS")) != 0)
277		termwidth = atoi(name);
278	else if (isatty(fileno(fp))) {
279		struct winsize win;
280
281		if (ioctl(fileno(fp), TIOCGWINSZ, &win) == 0 && win.ws_col > 0)
282			termwidth = win.ws_col;
283	}
284
285	pad = (len | 7) + 1 - len;
286	if (posix && pad)
287		pad = 1;
288
289	for (sig = 0; (sig = signalnext(sig)) != 0; ) {
290		name = signalname(sig);
291		if (name == NULL)
292			continue;
293
294		nl = strlen(name);
295
296		if (len > 0 && nl + len + pad >= termwidth) {
297			fprintf(fp, "\n");
298			len = 0;
299			pad = 0;
300		} else if (pad > 0 && len != 0)
301			fprintf(fp, "%*s", pad, "");
302		else
303			pad = 0;
304
305		len += nl + pad;
306		pad = (nl | 7) + 1 - nl;
307		if (posix && pad)
308			pad = 1;
309
310		fprintf(fp, "%s", name);
311	}
312	if (len != 0)
313		fprintf(fp, "\n");
314}
315#endif
316
317static void
318usage(void)
319{
320	const char *pn = getprogname();
321
322	fprintf(stderr, "usage: %s [-s signal_name] pid ...\n"
323			"       %s -l [exit_status]\n"
324			"       %s -signal_name pid ...\n"
325			"       %s -signal_number pid ...\n",
326	    pn, pn, pn, pn);
327	exit(1);
328	/* NOTREACHED */
329}
330