xref: /freebsd/bin/kill/kill.c (revision ba3c1f5972d7b90feb6e6da47905ff2757e0fe57)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
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  * Important: This file is used both as a standalone program /bin/kill and
33  * as a builtin for /bin/sh (#define SHELL).
34  */
35 
36 #if 0
37 #ifndef lint
38 static char const copyright[] =
39 "@(#) Copyright (c) 1988, 1993, 1994\n\
40 	The Regents of the University of California.  All rights reserved.\n";
41 #endif /* not lint */
42 
43 #ifndef lint
44 static char sccsid[] = "@(#)kill.c	8.4 (Berkeley) 4/28/95";
45 #endif /* not lint */
46 #endif
47 #include <sys/cdefs.h>
48 __FBSDID("$FreeBSD$");
49 
50 #include <ctype.h>
51 #include <err.h>
52 #include <errno.h>
53 #include <signal.h>
54 #include <stdio.h>
55 #include <stdlib.h>
56 #include <string.h>
57 
58 #ifdef SHELL
59 #define main killcmd
60 #include "bltin/bltin.h"
61 #endif
62 
63 static void nosig(const char *);
64 static void printsignals(FILE *);
65 static int signame_to_signum(const char *);
66 static void usage(void) __dead2;
67 
68 int
69 main(int argc, char *argv[])
70 {
71 	long pidl;
72 	pid_t pid;
73 	int errors, numsig, ret;
74 	char *ep;
75 
76 	if (argc < 2)
77 		usage();
78 
79 	numsig = SIGTERM;
80 
81 	argc--, argv++;
82 	if (!strcmp(*argv, "-l")) {
83 		argc--, argv++;
84 		if (argc > 1)
85 			usage();
86 		if (argc == 1) {
87 			if (!isdigit(**argv))
88 				usage();
89 			numsig = strtol(*argv, &ep, 10);
90 			if (!**argv || *ep)
91 				errx(2, "illegal signal number: %s", *argv);
92 			if (numsig >= 128)
93 				numsig -= 128;
94 			if (numsig <= 0 || numsig >= sys_nsig)
95 				nosig(*argv);
96 			printf("%s\n", sys_signame[numsig]);
97 			return (0);
98 		}
99 		printsignals(stdout);
100 		return (0);
101 	}
102 
103 	if (!strcmp(*argv, "-s")) {
104 		argc--, argv++;
105 		if (argc < 1) {
106 			warnx("option requires an argument -- s");
107 			usage();
108 		}
109 		if (strcmp(*argv, "0")) {
110 			if ((numsig = signame_to_signum(*argv)) < 0)
111 				nosig(*argv);
112 		} else
113 			numsig = 0;
114 		argc--, argv++;
115 	} else if (**argv == '-' && *(*argv + 1) != '-') {
116 		++*argv;
117 		if (isalpha(**argv)) {
118 			if ((numsig = signame_to_signum(*argv)) < 0)
119 				nosig(*argv);
120 		} else if (isdigit(**argv)) {
121 			numsig = strtol(*argv, &ep, 10);
122 			if (!**argv || *ep)
123 				errx(2, "illegal signal number: %s", *argv);
124 			if (numsig < 0)
125 				nosig(*argv);
126 		} else
127 			nosig(*argv);
128 		argc--, argv++;
129 	}
130 
131 	if (argc > 0 && strncmp(*argv, "--", 2) == 0)
132 		argc--, argv++;
133 
134 	if (argc == 0)
135 		usage();
136 
137 	for (errors = 0; argc; argc--, argv++) {
138 #ifdef SHELL
139 		if (**argv == '%')
140 			ret = killjob(*argv, numsig);
141 		else
142 #endif
143 		{
144 			pidl = strtol(*argv, &ep, 10);
145 			/* Check for overflow of pid_t. */
146 			pid = (pid_t)pidl;
147 			if (!**argv || *ep || pid != pidl)
148 				errx(2, "illegal process id: %s", *argv);
149 			ret = kill(pid, numsig);
150 		}
151 		if (ret == -1) {
152 			warn("%s", *argv);
153 			errors = 1;
154 		}
155 	}
156 
157 	return (errors);
158 }
159 
160 static int
161 signame_to_signum(const char *sig)
162 {
163 	int n;
164 
165 	if (strncasecmp(sig, "SIG", 3) == 0)
166 		sig += 3;
167 	for (n = 1; n < sys_nsig; n++) {
168 		if (!strcasecmp(sys_signame[n], sig))
169 			return (n);
170 	}
171 	return (-1);
172 }
173 
174 static void
175 nosig(const char *name)
176 {
177 
178 	warnx("unknown signal %s; valid signals:", name);
179 	printsignals(stderr);
180 #ifdef SHELL
181 	error(NULL);
182 #else
183 	exit(2);
184 #endif
185 }
186 
187 static void
188 printsignals(FILE *fp)
189 {
190 	int n;
191 
192 	for (n = 1; n < sys_nsig; n++) {
193 		(void)fprintf(fp, "%s", sys_signame[n]);
194 		if (n == (sys_nsig / 2) || n == (sys_nsig - 1))
195 			(void)fprintf(fp, "\n");
196 		else
197 			(void)fprintf(fp, " ");
198 	}
199 }
200 
201 static void
202 usage(void)
203 {
204 
205 	(void)fprintf(stderr, "%s\n%s\n%s\n%s\n",
206 		"usage: kill [-s signal_name] pid ...",
207 		"       kill -l [exit_status]",
208 		"       kill -signal_name pid ...",
209 		"       kill -signal_number pid ...");
210 #ifdef SHELL
211 	error(NULL);
212 #else
213 	exit(2);
214 #endif
215 }
216