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) __dead2;
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 * Interrupts are disabled; they should be reenabled when the exception is
78 * caught.
79 */
80
81 void
exraise(int e)82 exraise(int e)
83 {
84 INTOFF;
85 if (handler == NULL)
86 abort();
87 exception = e;
88 longjmp(handler->loc, 1);
89 }
90
91
92 /*
93 * Called from trap.c when a SIGINT is received. (If the user specifies
94 * that SIGINT is to be trapped or ignored using the trap builtin, then
95 * this routine is not called.) Suppressint is nonzero when interrupts
96 * are held using the INTOFF macro. If SIGINTs are not suppressed and
97 * the shell is not a root shell, then we want to be terminated if we
98 * get here, as if we were terminated directly by a SIGINT. Arrange for
99 * this here.
100 */
101
102 void
onint(void)103 onint(void)
104 {
105 sigset_t sigs;
106
107 /*
108 * The !in_dotrap here is safe. The only way we can arrive here
109 * with in_dotrap set is that a trap handler set SIGINT to SIG_DFL
110 * and killed itself.
111 */
112
113 if (suppressint && !in_dotrap) {
114 intpending++;
115 return;
116 }
117 intpending = 0;
118 sigemptyset(&sigs);
119 sigprocmask(SIG_SETMASK, &sigs, NULL);
120
121 /*
122 * This doesn't seem to be needed, since main() emits a newline.
123 */
124 #if 0
125 if (tcgetpgrp(0) == getpid())
126 write(STDERR_FILENO, "\n", 1);
127 #endif
128 if (rootshell && iflag)
129 exraise(EXINT);
130 else {
131 signal(SIGINT, SIG_DFL);
132 kill(getpid(), SIGINT);
133 }
134 }
135
136
137 static void
vwarning(const char * msg,va_list ap)138 vwarning(const char *msg, va_list ap)
139 {
140 if (commandname)
141 outfmt(out2, "%s: ", commandname);
142 doformat(out2, msg, ap);
143 out2fmt_flush("\n");
144 }
145
146
147 void
warning(const char * msg,...)148 warning(const char *msg, ...)
149 {
150 va_list ap;
151 va_start(ap, msg);
152 vwarning(msg, ap);
153 va_end(ap);
154 }
155
156
157 /*
158 * Exverror is called to raise the error exception. If the first argument
159 * is not NULL then error prints an error message using printf style
160 * formatting. It then raises the error exception.
161 */
162 static void
exverror(int cond,const char * msg,va_list ap)163 exverror(int cond, const char *msg, va_list ap)
164 {
165 /*
166 * An interrupt trumps an error. Certain places catch error
167 * exceptions or transform them to a plain nonzero exit code
168 * in child processes, and if an error exception can be handled,
169 * an interrupt can be handled as well.
170 *
171 * exraise() will disable interrupts for the exception handler.
172 */
173 FORCEINTON;
174
175 #ifdef DEBUG
176 if (msg)
177 TRACE(("exverror(%d, \"%s\") pid=%d\n", cond, msg, getpid()));
178 else
179 TRACE(("exverror(%d, NULL) pid=%d\n", cond, getpid()));
180 #endif
181 if (msg)
182 vwarning(msg, ap);
183 flushall();
184 exraise(cond);
185 }
186
187
188 void
error(const char * msg,...)189 error(const char *msg, ...)
190 {
191 va_list ap;
192 va_start(ap, msg);
193 exverror(EXERROR, msg, ap);
194 va_end(ap);
195 }
196
197
198 void
exerror(int cond,const char * msg,...)199 exerror(int cond, const char *msg, ...)
200 {
201 va_list ap;
202 va_start(ap, msg);
203 exverror(cond, msg, ap);
204 va_end(ap);
205 }
206