xref: /freebsd/bin/kill/kill.c (revision bc3f5ec90bde2f3a5e4021d133c89793d68b8c73)
1 /*-
2  * Copyright (c) 1988, 1993, 1994
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 /*
30  * Important: This file is used both as a standalone program /bin/kill and
31  * as a builtin for /bin/sh (#define SHELL).
32  */
33 
34 #if 0
35 #ifndef lint
36 static char const copyright[] =
37 "@(#) Copyright (c) 1988, 1993, 1994\n\
38 	The Regents of the University of California.  All rights reserved.\n";
39 #endif /* not lint */
40 
41 #ifndef lint
42 static char sccsid[] = "@(#)kill.c	8.4 (Berkeley) 4/28/95";
43 #endif /* not lint */
44 #endif
45 #include <sys/cdefs.h>
46 __FBSDID("$FreeBSD$");
47 
48 #include <ctype.h>
49 #include <err.h>
50 #include <errno.h>
51 #include <signal.h>
52 #include <stdio.h>
53 #include <stdlib.h>
54 #include <string.h>
55 
56 #ifdef SHELL
57 #define main killcmd
58 #include "bltin/bltin.h"
59 #include "error.h"
60 #endif
61 
62 static void nosig(const char *);
63 static void printsignals(FILE *);
64 static int signame_to_signum(const char *);
65 static void usage(void);
66 
67 int
68 main(int argc, char *argv[])
69 {
70 	int errors, numsig, pid;
71 	char *ep;
72 
73 	if (argc < 2)
74 		usage();
75 
76 	numsig = SIGTERM;
77 
78 	argc--, argv++;
79 	if (!strcmp(*argv, "-l")) {
80 		argc--, argv++;
81 		if (argc > 1)
82 			usage();
83 		if (argc == 1) {
84 			if (!isdigit(**argv))
85 				usage();
86 			numsig = strtol(*argv, &ep, 10);
87 			if (!**argv || *ep)
88 				errx(2, "illegal signal number: %s", *argv);
89 			if (numsig >= 128)
90 				numsig -= 128;
91 			if (numsig <= 0 || numsig >= sys_nsig)
92 				nosig(*argv);
93 			printf("%s\n", sys_signame[numsig]);
94 			return (0);
95 		}
96 		printsignals(stdout);
97 		return (0);
98 	}
99 
100 	if (!strcmp(*argv, "-s")) {
101 		argc--, argv++;
102 		if (argc < 1) {
103 			warnx("option requires an argument -- s");
104 			usage();
105 		}
106 		if (strcmp(*argv, "0")) {
107 			if ((numsig = signame_to_signum(*argv)) < 0)
108 				nosig(*argv);
109 		} else
110 			numsig = 0;
111 		argc--, argv++;
112 	} else if (**argv == '-' && *(*argv + 1) != '-') {
113 		++*argv;
114 		if (isalpha(**argv)) {
115 			if ((numsig = signame_to_signum(*argv)) < 0)
116 				nosig(*argv);
117 		} else if (isdigit(**argv)) {
118 			numsig = strtol(*argv, &ep, 10);
119 			if (!**argv || *ep)
120 				errx(2, "illegal signal number: %s", *argv);
121 			if (numsig < 0)
122 				nosig(*argv);
123 		} else
124 			nosig(*argv);
125 		argc--, argv++;
126 	}
127 
128 	if (argc > 0 && strncmp(*argv, "--", 2) == 0)
129 		argc--, argv++;
130 
131 	if (argc == 0)
132 		usage();
133 
134 	for (errors = 0; argc; argc--, argv++) {
135 #ifdef SHELL
136 		if (**argv == '%') {
137 			pid = getjobpgrp(*argv);
138 			/*
139 			 * Silently ignore terminated jobs, like the kernel
140 			 * silently ignores zombies.
141 			 */
142 			if (pid == 0)
143 				continue;
144 		} else
145 #endif
146 		{
147 			pid = strtol(*argv, &ep, 10);
148 			if (!**argv || *ep)
149 				errx(2, "illegal process id: %s", *argv);
150 		}
151 		if (kill(pid, numsig) == -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