xref: /netbsd-src/lib/libutil/ttyaction.c (revision 76dfffe33547c37f8bdd446e3e4ab0f3c16cea4b)
1 /*	$NetBSD: ttyaction.c,v 1.2 1996/11/14 19:16:02 gwr Exp $	*/
2 
3 /*-
4  * Copyright (c) 1996 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Gordon W. Ross.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE
30  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * For each matching "tty" and "action" run the "command."
41  * See fnmatch() for matching the tty name.
42  */
43 
44 #include <sys/types.h>
45 #include <sys/wait.h>
46 
47 #include <errno.h>
48 #include <fcntl.h>
49 #include <unistd.h>
50 #include <stdlib.h>
51 #include <stdio.h>
52 #include <string.h>
53 #include <paths.h>
54 
55 #include "util.h"
56 
57 #ifndef _PATH_TTYACTION
58 #define _PATH_TTYACTION "/etc/ttyaction"
59 #endif
60 
61 static char *actfile = _PATH_TTYACTION;
62 static char *pathenv = "PATH=" _PATH_STDPATH;
63 
64 int
65 ttyaction(tty, act, user)
66 	char *tty;
67 	char *act;
68 	char *user;
69 {
70 	FILE *fp;
71 	char *p1, *p2;
72 	char *argv[4];
73 	char *envp[8];
74 	char line[1024];
75 	char env_tty[64];
76 	char env_act[64];
77 	char env_user[256];
78 	int err, linenum, pid, status;
79 
80 	fp = fopen(actfile, "r");
81 	if (fp == NULL)
82 		return 0;
83 
84 	/* Skip the "/dev/" part of the first arg. */
85 	if (!strncmp(tty, "/dev/", 5))
86 		tty += 5;
87 
88 	/* Args will be: "sh -c ..." */
89 	argv[0] = _PATH_BSHELL;
90 	argv[1] = "-c";
91 	argv[2] = NULL;	/* see below */
92 	argv[3] = NULL;
93 
94 	/* Environment needs: TTY, ACT, USER */
95 	sprintf(env_tty, "TTY=%.63s", tty);
96 	sprintf(env_act, "ACT=%.63s", act);
97 	sprintf(env_user, "USER=%.255s", user);
98 	envp[0] = pathenv;
99 	envp[1] = env_tty;
100 	envp[2] = env_act;
101 	envp[3] = env_user;
102 	envp[4] = NULL;
103 
104 	linenum = 0;
105 	status = 0;
106 	while (fgets(line, sizeof(line), fp)) {
107 		linenum++;
108 
109 		/* Allow comment lines. */
110 		if (line[0] == '#')
111 			continue;
112 
113 		p1 = strtok(line, " \t");
114 		p2 = strtok(NULL, " \t");
115 		/* This arg goes to end of line. */
116 		argv[2] = strtok(NULL, "\n");
117 		if (!p1 || !p2 || !argv[2]) {
118 			warnx("%s: line %d format error", actfile, linenum);
119 			continue;
120 		}
121 		if (fnmatch(p1, tty, 0) || fnmatch(p2, act, 0))
122 			continue;
123 		/* OK, this is a match.  Run the command. */
124 		pid = fork();
125 		if (pid == -1) {
126 			warnx("fork failed: %s", strerror(errno));
127 			continue;
128 		}
129 		if (pid == 0) {
130 			/* This is the child. */
131 			err = execve(argv[0], argv, envp);
132 			/* If we get here, it is an error. */
133 			warnx("%s: line %d: exec failed: %s",
134 				  actfile, linenum, strerror(errno));
135 			exit(1);
136 		}
137 		/* This is the parent. */
138 		err = waitpid(pid, &status, 0);
139 		if (err == -1) {
140 			warnx("%s: line %d: wait failed: %s",
141 				  actfile, linenum, strerror(errno));
142 			continue;
143 		}
144 		if (WTERMSIG(status)) {
145 			warnx("%s: line %d: child died with signal %d",
146 				  actfile, linenum, WTERMSIG(status));
147 			continue;
148 		}
149 	}
150 	fclose(fp);
151 	return status;
152 }
153 
154