xref: /freebsd/bin/sh/error.c (revision 5861f9665471e98e544f6fa3ce73c4912229ff82)
1 /*-
2  * Copyright (c) 1991, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Kenneth Almquist.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 4. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #ifndef lint
34 #if 0
35 static char sccsid[] = "@(#)error.c	8.2 (Berkeley) 5/4/95";
36 #endif
37 #endif /* not lint */
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
40 
41 /*
42  * Errors and exceptions.
43  */
44 
45 #include "shell.h"
46 #include "main.h"
47 #include "options.h"
48 #include "output.h"
49 #include "error.h"
50 #include "nodes.h" /* show.h needs nodes.h */
51 #include "show.h"
52 #include "trap.h"
53 #include <signal.h>
54 #include <stdlib.h>
55 #include <unistd.h>
56 #include <errno.h>
57 
58 
59 /*
60  * Code to handle exceptions in C.
61  */
62 
63 struct jmploc *handler;
64 volatile sig_atomic_t exception;
65 volatile sig_atomic_t suppressint;
66 volatile sig_atomic_t intpending;
67 char *commandname;
68 
69 
70 static void exverror(int, const char *, va_list) __printf0like(2, 0);
71 
72 /*
73  * Called to raise an exception.  Since C doesn't include exceptions, we
74  * just do a longjmp to the exception handler.  The type of exception is
75  * stored in the global variable "exception".
76  */
77 
78 void
79 exraise(int e)
80 {
81 	if (handler == NULL)
82 		abort();
83 	exception = e;
84 	longjmp(handler->loc, 1);
85 }
86 
87 
88 /*
89  * Called from trap.c when a SIGINT is received.  (If the user specifies
90  * that SIGINT is to be trapped or ignored using the trap builtin, then
91  * this routine is not called.)  Suppressint is nonzero when interrupts
92  * are held using the INTOFF macro.  If SIGINTs are not suppressed and
93  * the shell is not a root shell, then we want to be terminated if we
94  * get here, as if we were terminated directly by a SIGINT.  Arrange for
95  * this here.
96  */
97 
98 void
99 onint(void)
100 {
101 	sigset_t sigset;
102 
103 	/*
104 	 * The !in_dotrap here is safe.  The only way we can arrive here
105 	 * with in_dotrap set is that a trap handler set SIGINT to SIG_DFL
106 	 * and killed itself.
107 	 */
108 
109 	if (suppressint && !in_dotrap) {
110 		intpending++;
111 		return;
112 	}
113 	intpending = 0;
114 	sigemptyset(&sigset);
115 	sigprocmask(SIG_SETMASK, &sigset, NULL);
116 
117 	/*
118 	 * This doesn't seem to be needed, since main() emits a newline.
119 	 */
120 #if 0
121 	if (tcgetpgrp(0) == getpid())
122 		write(STDERR_FILENO, "\n", 1);
123 #endif
124 	if (rootshell && iflag)
125 		exraise(EXINT);
126 	else {
127 		signal(SIGINT, SIG_DFL);
128 		kill(getpid(), SIGINT);
129 	}
130 }
131 
132 
133 /*
134  * Exverror is called to raise the error exception.  If the first argument
135  * is not NULL then error prints an error message using printf style
136  * formatting.  It then raises the error exception.
137  */
138 static void
139 exverror(int cond, const char *msg, va_list ap)
140 {
141 	CLEAR_PENDING_INT;
142 	INTOFF;
143 
144 #ifdef DEBUG
145 	if (msg)
146 		TRACE(("exverror(%d, \"%s\") pid=%d\n", cond, msg, getpid()));
147 	else
148 		TRACE(("exverror(%d, NULL) pid=%d\n", cond, getpid()));
149 #endif
150 	if (msg) {
151 		if (commandname)
152 			outfmt(&errout, "%s: ", commandname);
153 		doformat(&errout, msg, ap);
154 		out2c('\n');
155 	}
156 	flushall();
157 	exraise(cond);
158 }
159 
160 
161 void
162 error(const char *msg, ...)
163 {
164 	va_list ap;
165 	va_start(ap, msg);
166 	exverror(EXERROR, msg, ap);
167 	va_end(ap);
168 }
169 
170 
171 void
172 exerror(int cond, const char *msg, ...)
173 {
174 	va_list ap;
175 	va_start(ap, msg);
176 	exverror(cond, msg, ap);
177 	va_end(ap);
178 }
179