xref: /freebsd/bin/sh/error.c (revision 6990ffd8a95caaba6858ad44ff1b3157d1efba8f)
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. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #ifndef lint
38 #if 0
39 static char sccsid[] = "@(#)error.c	8.2 (Berkeley) 5/4/95";
40 #endif
41 static const char rcsid[] =
42   "$FreeBSD$";
43 #endif /* not lint */
44 
45 /*
46  * Errors and exceptions.
47  */
48 
49 #include "shell.h"
50 #include "main.h"
51 #include "options.h"
52 #include "output.h"
53 #include "error.h"
54 #include "nodes.h" /* show.h needs nodes.h */
55 #include "show.h"
56 #include "trap.h"
57 #include <signal.h>
58 #include <stdlib.h>
59 #include <unistd.h>
60 #include <errno.h>
61 
62 
63 /*
64  * Code to handle exceptions in C.
65  */
66 
67 struct jmploc *handler;
68 volatile sig_atomic_t exception;
69 volatile sig_atomic_t suppressint;
70 volatile sig_atomic_t intpending;
71 char *commandname;
72 
73 
74 static void exverror __P((int, const char *, va_list)) __printf0like(2, 0);
75 
76 /*
77  * Called to raise an exception.  Since C doesn't include exceptions, we
78  * just do a longjmp to the exception handler.  The type of exception is
79  * stored in the global variable "exception".
80  */
81 
82 void
83 exraise(e)
84 	int e;
85 {
86 	if (handler == NULL)
87 		abort();
88 	exception = e;
89 	longjmp(handler->loc, 1);
90 }
91 
92 
93 /*
94  * Called from trap.c when a SIGINT is received.  (If the user specifies
95  * that SIGINT is to be trapped or ignored using the trap builtin, then
96  * this routine is not called.)  Suppressint is nonzero when interrupts
97  * are held using the INTOFF macro.  If SIGINTs are not suppressed and
98  * the shell is not a root shell, then we want to be terminated if we
99  * get here, as if we were terminated directly by a SIGINT.  Arrange for
100  * this here.
101  */
102 
103 void
104 onint() {
105 	sigset_t sigset;
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(&sigset);
119 	sigprocmask(SIG_SETMASK, &sigset, 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 /*
138  * Exverror is called to raise the error exception.  If the first argument
139  * is not NULL then error prints an error message using printf style
140  * formatting.  It then raises the error exception.
141  */
142 static void
143 exverror(cond, msg, ap)
144 	int cond;
145 	const char *msg;
146 	va_list ap;
147 {
148 	CLEAR_PENDING_INT;
149 	INTOFF;
150 
151 #ifdef DEBUG
152 	if (msg)
153 		TRACE(("exverror(%d, \"%s\") pid=%d\n", cond, msg, getpid()));
154 	else
155 		TRACE(("exverror(%d, NULL) pid=%d\n", cond, getpid()));
156 #endif
157 	if (msg) {
158 		if (commandname)
159 			outfmt(&errout, "%s: ", commandname);
160 		doformat(&errout, msg, ap);
161 		out2c('\n');
162 	}
163 	flushall();
164 	exraise(cond);
165 }
166 
167 
168 #ifdef __STDC__
169 void
170 error(const char *msg, ...)
171 #else
172 void
173 error(va_alist)
174 	va_dcl
175 #endif
176 {
177 #ifndef __STDC__
178 	const char *msg;
179 #endif
180 	va_list ap;
181 #ifdef __STDC__
182 	va_start(ap, msg);
183 #else
184 	va_start(ap);
185 	msg = va_arg(ap, char *);
186 #endif
187 	exverror(EXERROR, msg, ap);
188 	va_end(ap);
189 }
190 
191 
192 #ifdef __STDC__
193 void
194 exerror(int cond, const char *msg, ...)
195 #else
196 void
197 exerror(va_alist)
198 	va_dcl
199 #endif
200 {
201 #ifndef __STDC__
202 	int cond;
203 	char *msg;
204 #endif
205 	va_list ap;
206 #ifdef __STDC__
207 	va_start(ap, msg);
208 #else
209 	va_start(ap);
210 	cond = va_arg(ap, int);
211 	msg = va_arg(ap, char *);
212 #endif
213 	exverror(cond, msg, ap);
214 	va_end(ap);
215 }
216 
217 
218 
219 /*
220  * Table of error messages.
221  */
222 
223 struct errname {
224 	short errcode;		/* error number */
225 	short action;		/* operation which encountered the error */
226 	char *msg;		/* text describing the error */
227 };
228 
229 
230 #define ALL (E_OPEN|E_CREAT|E_EXEC)
231 
232 STATIC const struct errname errormsg[] = {
233 	{ EINTR,	ALL,	"interrupted" },
234 	{ EACCES,	ALL,	"permission denied" },
235 	{ EIO,		ALL,	"I/O error" },
236 	{ ENOENT,	E_OPEN,	"no such file" },
237 	{ ENOENT,	E_CREAT,"directory nonexistent" },
238 	{ ENOENT,	E_EXEC,	"not found" },
239 	{ ENOTDIR,	E_OPEN,	"no such file" },
240 	{ ENOTDIR,	E_CREAT,"directory nonexistent" },
241 	{ ENOTDIR,	E_EXEC,	"not found" },
242 	{ EISDIR,	ALL,	"is a directory" },
243 #ifdef notdef
244 	{ EMFILE,	ALL,	"too many open files" },
245 #endif
246 	{ ENFILE,	ALL,	"file table overflow" },
247 	{ ENOSPC,	ALL,	"file system full" },
248 #ifdef EDQUOT
249 	{ EDQUOT,	ALL,	"disk quota exceeded" },
250 #endif
251 #ifdef ENOSR
252 	{ ENOSR,	ALL,	"no streams resources" },
253 #endif
254 	{ ENXIO,	ALL,	"no such device or address" },
255 	{ EROFS,	ALL,	"read-only file system" },
256 	{ ETXTBSY,	ALL,	"text busy" },
257 #ifdef SYSV
258 	{ EAGAIN,	E_EXEC,	"not enough memory" },
259 #endif
260 	{ ENOMEM,	ALL,	"not enough memory" },
261 #ifdef ENOLINK
262 	{ ENOLINK,	ALL,	"remote access failed" },
263 #endif
264 #ifdef EMULTIHOP
265 	{ EMULTIHOP,	ALL,	"remote access failed" },
266 #endif
267 #ifdef ECOMM
268 	{ ECOMM,	ALL,	"remote access failed" },
269 #endif
270 #ifdef ESTALE
271 	{ ESTALE,	ALL,	"remote access failed" },
272 #endif
273 #ifdef ETIMEDOUT
274 	{ ETIMEDOUT,	ALL,	"remote access failed" },
275 #endif
276 #ifdef ELOOP
277 	{ ELOOP,	ALL,	"symbolic link loop" },
278 #endif
279 	{ E2BIG,	E_EXEC,	"argument list too long" },
280 #ifdef ELIBACC
281 	{ ELIBACC,	E_EXEC,	"shared library missing" },
282 #endif
283 	{ 0,		0,	NULL },
284 };
285 
286 
287 /*
288  * Return a string describing an error.  The returned string may be a
289  * pointer to a static buffer that will be overwritten on the next call.
290  * Action describes the operation that got the error.
291  */
292 
293 char *
294 errmsg(e, action)
295 	int e;
296 	int action;
297 {
298 	struct errname const *ep;
299 	static char buf[12];
300 
301 	for (ep = errormsg ; ep->errcode ; ep++) {
302 		if (ep->errcode == e && (ep->action & action) != 0)
303 			return ep->msg;
304 	}
305 	fmtstr(buf, sizeof buf, "error %d", e);
306 	return buf;
307 }
308