error.c revision 53891 
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  "$FreeBSD: head/bin/sh/error.c 53891 1999-11-29 19:11:01Z cracauer $";
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 <unistd.h>
59#include <errno.h>
60
61
62/*
63 * Code to handle exceptions in C.
64 */
65
66struct jmploc *handler;
67volatile sig_atomic_t exception;
68volatile sig_atomic_t suppressint;
69volatile sig_atomic_t intpending;
70char *commandname;
71
72
73static void exverror __P((int, char *, va_list));
74
75/*
76 * Called to raise an exception.  Since C doesn't include exceptions, we
77 * just do a longjmp to the exception handler.  The type of exception is
78 * stored in the global variable "exception".
79 */
80
81void
82exraise(e)
83	int e;
84{
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
102void
103onint() {
104	sigset_t sigset;
105
106	/*
107	 * The !in_dotrap here is safe.  The only way we can arrive here
108	 * with in_dotrap set is that a trap handler set SIGINT to SIG_DFL
109	 * and killed itself.
110	 */
111
112	if (suppressint && !in_dotrap) {
113		intpending++;
114		return;
115	}
116	intpending = 0;
117	sigemptyset(&sigset);
118	sigprocmask(SIG_SETMASK, &sigset, NULL);
119
120	/*
121	 * This doesn't seem to be needed, since main() emits a newline.
122	 */
123#if 0
124	if (tcgetpgrp(0) == getpid())
125		write(STDERR_FILENO, "\n", 1);
126#endif
127	if (rootshell && iflag)
128		exraise(EXINT);
129	else {
130		signal(SIGINT, SIG_DFL);
131		kill(getpid(), SIGINT);
132	}
133}
134
135
136/*
137 * Exverror is called to raise the error exception.  If the first argument
138 * is not NULL then error prints an error message using printf style
139 * formatting.  It then raises the error exception.
140 */
141static void
142exverror(cond, msg, ap)
143	int cond;
144	char *msg;
145	va_list ap;
146{
147	CLEAR_PENDING_INT;
148	INTOFF;
149
150#ifdef DEBUG
151	if (msg)
152		TRACE(("exverror(%d, \"%s\") pid=%d\n", cond, msg, getpid()));
153	else
154		TRACE(("exverror(%d, NULL) pid=%d\n", cond, getpid()));
155#endif
156	if (msg) {
157		if (commandname)
158			outfmt(&errout, "%s: ", commandname);
159		doformat(&errout, msg, ap);
160		out2c('\n');
161	}
162	flushall();
163	exraise(cond);
164}
165
166
167#ifdef __STDC__
168void
169error(char *msg, ...)
170#else
171void
172error(va_alist)
173	va_dcl
174#endif
175{
176#ifndef __STDC__
177	char *msg;
178#endif
179	va_list ap;
180#ifdef __STDC__
181	va_start(ap, msg);
182#else
183	va_start(ap);
184	msg = va_arg(ap, char *);
185#endif
186	exverror(EXERROR, msg, ap);
187	va_end(ap);
188}
189
190
191#ifdef __STDC__
192void
193exerror(int cond, char *msg, ...)
194#else
195void
196exerror(va_alist)
197	va_dcl
198#endif
199{
200#ifndef __STDC__
201	int cond;
202	char *msg;
203#endif
204	va_list ap;
205#ifdef __STDC__
206	va_start(ap, msg);
207#else
208	va_start(ap);
209	cond = va_arg(ap, int);
210	msg = va_arg(ap, char *);
211#endif
212	exverror(cond, msg, ap);
213	va_end(ap);
214}
215
216
217
218/*
219 * Table of error messages.
220 */
221
222struct errname {
223	short errcode;		/* error number */
224	short action;		/* operation which encountered the error */
225	char *msg;		/* text describing the error */
226};
227
228
229#define ALL (E_OPEN|E_CREAT|E_EXEC)
230
231STATIC const struct errname errormsg[] = {
232	{ EINTR,	ALL,	"interrupted" },
233	{ EACCES,	ALL,	"permission denied" },
234	{ EIO,		ALL,	"I/O error" },
235	{ ENOENT,	E_OPEN,	"no such file" },
236	{ ENOENT,	E_CREAT,"directory nonexistent" },
237	{ ENOENT,	E_EXEC,	"not found" },
238	{ ENOTDIR,	E_OPEN,	"no such file" },
239	{ ENOTDIR,	E_CREAT,"directory nonexistent" },
240	{ ENOTDIR,	E_EXEC,	"not found" },
241	{ EISDIR,	ALL,	"is a directory" },
242#ifdef notdef
243	{ EMFILE,	ALL,	"too many open files" },
244#endif
245	{ ENFILE,	ALL,	"file table overflow" },
246	{ ENOSPC,	ALL,	"file system full" },
247#ifdef EDQUOT
248	{ EDQUOT,	ALL,	"disk quota exceeded" },
249#endif
250#ifdef ENOSR
251	{ ENOSR,	ALL,	"no streams resources" },
252#endif
253	{ ENXIO,	ALL,	"no such device or address" },
254	{ EROFS,	ALL,	"read-only file system" },
255	{ ETXTBSY,	ALL,	"text busy" },
256#ifdef SYSV
257	{ EAGAIN,	E_EXEC,	"not enough memory" },
258#endif
259	{ ENOMEM,	ALL,	"not enough memory" },
260#ifdef ENOLINK
261	{ ENOLINK,	ALL,	"remote access failed" },
262#endif
263#ifdef EMULTIHOP
264	{ EMULTIHOP,	ALL,	"remote access failed" },
265#endif
266#ifdef ECOMM
267	{ ECOMM,	ALL,	"remote access failed" },
268#endif
269#ifdef ESTALE
270	{ ESTALE,	ALL,	"remote access failed" },
271#endif
272#ifdef ETIMEDOUT
273	{ ETIMEDOUT,	ALL,	"remote access failed" },
274#endif
275#ifdef ELOOP
276	{ ELOOP,	ALL,	"symbolic link loop" },
277#endif
278	{ E2BIG,	E_EXEC,	"argument list too long" },
279#ifdef ELIBACC
280	{ ELIBACC,	E_EXEC,	"shared library missing" },
281#endif
282	{ 0,		0,	NULL },
283};
284
285
286/*
287 * Return a string describing an error.  The returned string may be a
288 * pointer to a static buffer that will be overwritten on the next call.
289 * Action describes the operation that got the error.
290 */
291
292char *
293errmsg(e, action)
294	int e;
295	int action;
296{
297	struct errname const *ep;
298	static char buf[12];
299
300	for (ep = errormsg ; ep->errcode ; ep++) {
301		if (ep->errcode == e && (ep->action & action) != 0)
302			return ep->msg;
303	}
304	fmtstr(buf, sizeof buf, "error %d", e);
305	return buf;
306}
307