error.c revision 36150 
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
39static char sccsid[] = "@(#)error.c	8.2 (Berkeley) 5/4/95";
40#endif
41static const char rcsid[] =
42	"$Id$";
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 "show.h"
55#include <signal.h>
56#include <unistd.h>
57#include <errno.h>
58
59
60/*
61 * Code to handle exceptions in C.
62 */
63
64struct jmploc *handler;
65int exception;
66volatile int suppressint;
67volatile int intpending;
68char *commandname;
69
70
71static void exverror __P((int, char *, va_list));
72
73/*
74 * Called to raise an exception.  Since C doesn't include exceptions, we
75 * just do a longjmp to the exception handler.  The type of exception is
76 * stored in the global variable "exception".
77 */
78
79void
80exraise(e)
81	int e;
82{
83	if (handler == NULL)
84		abort();
85	exception = e;
86	longjmp(handler->loc, 1);
87}
88
89
90/*
91 * Called from trap.c when a SIGINT is received.  (If the user specifies
92 * that SIGINT is to be trapped or ignored using the trap builtin, then
93 * this routine is not called.)  Suppressint is nonzero when interrupts
94 * are held using the INTOFF macro.  The call to _exit is necessary because
95 * there is a short period after a fork before the signal handlers are
96 * set to the appropriate value for the child.  (The test for iflag is
97 * just defensive programming.)
98 */
99
100void
101onint() {
102	sigset_t sigset;
103
104	if (suppressint) {
105		intpending++;
106		return;
107	}
108	intpending = 0;
109	sigemptyset(&sigset);
110	sigprocmask(SIG_SETMASK, &sigset, NULL);
111	out2str("\n");
112	if (rootshell && iflag)
113		exraise(EXINT);
114	else
115		_exit(128 + SIGINT);
116}
117
118
119/*
120 * Exverror is called to raise the error exception.  If the first argument
121 * is not NULL then error prints an error message using printf style
122 * formatting.  It then raises the error exception.
123 */
124static void
125exverror(cond, msg, ap)
126	int cond;
127	char *msg;
128	va_list ap;
129{
130	CLEAR_PENDING_INT;
131	INTOFF;
132
133#ifdef DEBUG
134	if (msg)
135		TRACE(("exverror(%d, \"%s\") pid=%d\n", cond, msg, getpid()));
136	else
137		TRACE(("exverror(%d, NULL) pid=%d\n", cond, getpid()));
138#endif
139	if (msg) {
140		if (commandname)
141			outfmt(&errout, "%s: ", commandname);
142		doformat(&errout, msg, ap);
143		out2c('\n');
144	}
145	flushall();
146	exraise(cond);
147}
148
149
150#ifdef __STDC__
151void
152error(char *msg, ...)
153#else
154void
155error(va_alist)
156	va_dcl
157#endif
158{
159#ifndef __STDC__
160	char *msg;
161#endif
162	va_list ap;
163#ifdef __STDC__
164	va_start(ap, msg);
165#else
166	va_start(ap);
167	msg = va_arg(ap, char *);
168#endif
169	exverror(EXERROR, msg, ap);
170	va_end(ap);
171}
172
173
174#ifdef __STDC__
175void
176exerror(int cond, char *msg, ...)
177#else
178void
179exerror(va_alist)
180	va_dcl
181#endif
182{
183#ifndef __STDC__
184	int cond;
185	char *msg;
186#endif
187	va_list ap;
188#ifdef __STDC__
189	va_start(ap, msg);
190#else
191	va_start(ap);
192	cond = va_arg(ap, int);
193	msg = va_arg(ap, char *);
194#endif
195	exverror(cond, msg, ap);
196	va_end(ap);
197}
198
199
200
201/*
202 * Table of error messages.
203 */
204
205struct errname {
206	short errcode;		/* error number */
207	short action;		/* operation which encountered the error */
208	char *msg;		/* text describing the error */
209};
210
211
212#define ALL (E_OPEN|E_CREAT|E_EXEC)
213
214STATIC const struct errname errormsg[] = {
215	{ EINTR,	ALL,	"interrupted" },
216	{ EACCES,	ALL,	"permission denied" },
217	{ EIO,		ALL,	"I/O error" },
218	{ ENOENT,	E_OPEN,	"no such file" },
219	{ ENOENT,	E_CREAT,"directory nonexistent" },
220	{ ENOENT,	E_EXEC,	"not found" },
221	{ ENOTDIR,	E_OPEN,	"no such file" },
222	{ ENOTDIR,	E_CREAT,"directory nonexistent" },
223	{ ENOTDIR,	E_EXEC,	"not found" },
224	{ EISDIR,	ALL,	"is a directory" },
225#ifdef notdef
226	{ EMFILE,	ALL,	"too many open files" },
227#endif
228	{ ENFILE,	ALL,	"file table overflow" },
229	{ ENOSPC,	ALL,	"file system full" },
230#ifdef EDQUOT
231	{ EDQUOT,	ALL,	"disk quota exceeded" },
232#endif
233#ifdef ENOSR
234	{ ENOSR,	ALL,	"no streams resources" },
235#endif
236	{ ENXIO,	ALL,	"no such device or address" },
237	{ EROFS,	ALL,	"read-only file system" },
238	{ ETXTBSY,	ALL,	"text busy" },
239#ifdef SYSV
240	{ EAGAIN,	E_EXEC,	"not enough memory" },
241#endif
242	{ ENOMEM,	ALL,	"not enough memory" },
243#ifdef ENOLINK
244	{ ENOLINK,	ALL,	"remote access failed" },
245#endif
246#ifdef EMULTIHOP
247	{ EMULTIHOP,	ALL,	"remote access failed" },
248#endif
249#ifdef ECOMM
250	{ ECOMM,	ALL,	"remote access failed" },
251#endif
252#ifdef ESTALE
253	{ ESTALE,	ALL,	"remote access failed" },
254#endif
255#ifdef ETIMEDOUT
256	{ ETIMEDOUT,	ALL,	"remote access failed" },
257#endif
258#ifdef ELOOP
259	{ ELOOP,	ALL,	"symbolic link loop" },
260#endif
261	{ E2BIG,	E_EXEC,	"argument list too long" },
262#ifdef ELIBACC
263	{ ELIBACC,	E_EXEC,	"shared library missing" },
264#endif
265	{ 0,		0,	NULL },
266};
267
268
269/*
270 * Return a string describing an error.  The returned string may be a
271 * pointer to a static buffer that will be overwritten on the next call.
272 * Action describes the operation that got the error.
273 */
274
275char *
276errmsg(e, action)
277	int e;
278	int action;
279{
280	struct errname const *ep;
281	static char buf[12];
282
283	for (ep = errormsg ; ep->errcode ; ep++) {
284		if (ep->errcode == e && (ep->action & action) != 0)
285			return ep->msg;
286	}
287	fmtstr(buf, sizeof buf, "error %d", e);
288	return buf;
289}
290