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 * 3. 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 /*
34 * Errors and exceptions.
35 */
36
37 #include "shell.h"
38 #include "eval.h"
39 #include "main.h"
40 #include "options.h"
41 #include "output.h"
42 #include "error.h"
43 #include "nodes.h" /* show.h needs nodes.h */
44 #include "show.h"
45 #include "trap.h"
46 #include <signal.h>
47 #include <stdlib.h>
48 #include <unistd.h>
49 #include <errno.h>
50
51
52 /*
53 * Code to handle exceptions in C.
54 */
55
56 struct jmploc *handler;
57 volatile sig_atomic_t exception;
58 volatile sig_atomic_t suppressint;
59 volatile sig_atomic_t intpending;
60
61
62 static void verrorwithstatus(int, const char *, va_list) __printf0like(2, 0) __dead2;
63
64 /*
65 * Called to raise an exception. Since C doesn't include exceptions, we
66 * just do a longjmp to the exception handler. The type of exception is
67 * stored in the global variable "exception".
68 *
69 * Interrupts are disabled; they should be re-enabled when the exception is
70 * caught.
71 */
72
73 void
exraise(int e)74 exraise(int e)
75 {
76 INTOFF;
77 if (handler == NULL)
78 abort();
79 exception = e;
80 longjmp(handler->loc, 1);
81 }
82
83
84 /*
85 * Called from trap.c when a SIGINT is received and not suppressed, or when
86 * an interrupt is pending and interrupts are re-enabled using INTON.
87 * (If the user specifies that SIGINT is to be trapped or ignored using the
88 * trap builtin, then this routine is not called.) Suppressint is nonzero
89 * when interrupts are held using the INTOFF macro. If SIGINTs are not
90 * suppressed and the shell is not a root shell, then we want to be
91 * terminated if we get here, as if we were terminated directly by a SIGINT.
92 * Arrange for this here.
93 */
94
95 void
onint(void)96 onint(void)
97 {
98 sigset_t sigs;
99
100 intpending = 0;
101 sigemptyset(&sigs);
102 sigprocmask(SIG_SETMASK, &sigs, NULL);
103
104 /*
105 * This doesn't seem to be needed, since main() emits a newline.
106 */
107 #if 0
108 if (tcgetpgrp(0) == getpid())
109 write(STDERR_FILENO, "\n", 1);
110 #endif
111 if (rootshell && iflag)
112 exraise(EXINT);
113 else {
114 signal(SIGINT, SIG_DFL);
115 kill(getpid(), SIGINT);
116 _exit(128 + SIGINT);
117 }
118 }
119
120
121 static void
vwarning(const char * msg,va_list ap)122 vwarning(const char *msg, va_list ap)
123 {
124 if (commandname)
125 outfmt(out2, "%s: ", commandname);
126 else if (arg0)
127 outfmt(out2, "%s: ", arg0);
128 doformat(out2, msg, ap);
129 out2fmt_flush("\n");
130 }
131
132
133 void
warning(const char * msg,...)134 warning(const char *msg, ...)
135 {
136 va_list ap;
137 va_start(ap, msg);
138 vwarning(msg, ap);
139 va_end(ap);
140 }
141
142
143 /*
144 * Exverror is called to raise the error exception. If the first argument
145 * is not NULL then error prints an error message using printf style
146 * formatting. It then raises the error exception.
147 */
148 static void
verrorwithstatus(int status,const char * msg,va_list ap)149 verrorwithstatus(int status, const char *msg, va_list ap)
150 {
151 /*
152 * An interrupt trumps an error. Certain places catch error
153 * exceptions or transform them to a plain nonzero exit code
154 * in child processes, and if an error exception can be handled,
155 * an interrupt can be handled as well.
156 *
157 * exraise() will disable interrupts for the exception handler.
158 */
159 FORCEINTON;
160
161 #ifdef DEBUG
162 if (msg)
163 TRACE(("verrorwithstatus(%d, \"%s\") pid=%d\n",
164 status, msg, getpid()));
165 else
166 TRACE(("verrorwithstatus(%d, NULL) pid=%d\n",
167 status, getpid()));
168 #endif
169 if (msg)
170 vwarning(msg, ap);
171 flushall();
172 exitstatus = status;
173 exraise(EXERROR);
174 }
175
176
177 void
error(const char * msg,...)178 error(const char *msg, ...)
179 {
180 va_list ap;
181 va_start(ap, msg);
182 verrorwithstatus(2, msg, ap);
183 va_end(ap);
184 }
185
186
187 void
errorwithstatus(int status,const char * msg,...)188 errorwithstatus(int status, const char *msg, ...)
189 {
190 va_list ap;
191 va_start(ap, msg);
192 verrorwithstatus(status, msg, ap);
193 va_end(ap);
194 }
195