error.c revision 38536 
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: error.c,v 1.12 1998/08/24 19:15:48 cracauer Exp $";
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 "trap.h"
56#include <signal.h>
57#include <unistd.h>
58#include <errno.h>
59
60
61/*
62 * Code to handle exceptions in C.
63 */
64
65struct jmploc *handler;
66volatile sig_atomic_t exception;
67volatile sig_atomic_t suppressint;
68volatile sig_atomic_t intpending;
69char *commandname;
70
71
72static void exverror __P((int, char *, va_list));
73
74/*
75 * Called to raise an exception.  Since C doesn't include exceptions, we
76 * just do a longjmp to the exception handler.  The type of exception is
77 * stored in the global variable "exception".
78 */
79
80void
81exraise(e)
82	int e;
83{
84	if (handler == NULL)
85		abort();
86	exception = e;
87	longjmp(handler->loc, 1);
88}
89
90
91/*
92 * Called from trap.c when a SIGINT is received.  (If the user specifies
93 * that SIGINT is to be trapped or ignored using the trap builtin, then
94 * this routine is not called.)  Suppressint is nonzero when interrupts
95 * are held using the INTOFF macro.  If SIGINTs are not suppressed and
96 * the shell is not a root shell, then we want to be terminated if we
97 * get here, as if we were terminated directly by a SIGINT.  Arrange for
98 * this here.
99 */
100
101void
102onint() {
103	sigset_t sigset;
104
105	/*
106	 * The !in_dotrap here is safe.  The only way we can arrive here
107	 * with in_dotrap set is that a trap handler set SIGINT to SIG_DFL
108	 * and killed itself.
109	 */
110
111	if (suppressint && !in_dotrap) {
112		intpending++;
113		return;
114	}
115	intpending = 0;
116	sigemptyset(&sigset);
117	sigprocmask(SIG_SETMASK, &sigset, NULL);
118
119	/*
120	 * This doesn't seem to be needed, since main() emits a newline.
121	 */
122#if 0
123	if (tcgetpgrp(0) == getpid())
124		write(STDERR_FILENO, "\n", 1);
125#endif
126	if (rootshell && iflag)
127		exraise(EXINT);
128	else {
129		signal(SIGINT, SIG_DFL);
130		kill(getpid(), SIGINT);
131	}
132}
133
134
135/*
136 * Exverror is called to raise the error exception.  If the first argument
137 * is not NULL then error prints an error message using printf style
138 * formatting.  It then raises the error exception.
139 */
140static void
141exverror(cond, msg, ap)
142	int cond;
143	char *msg;
144	va_list ap;
145{
146	CLEAR_PENDING_INT;
147	INTOFF;
148
149#ifdef DEBUG
150	if (msg)
151		TRACE(("exverror(%d, \"%s\") pid=%d\n", cond, msg, getpid()));
152	else
153		TRACE(("exverror(%d, NULL) pid=%d\n", cond, getpid()));
154#endif
155	if (msg) {
156		if (commandname)
157			outfmt(&errout, "%s: ", commandname);
158		doformat(&errout, msg, ap);
159		out2c('\n');
160	}
161	flushall();
162	exraise(cond);
163}
164
165
166#ifdef __STDC__
167void
168error(char *msg, ...)
169#else
170void
171error(va_alist)
172	va_dcl
173#endif
174{
175#ifndef __STDC__
176	char *msg;
177#endif
178	va_list ap;
179#ifdef __STDC__
180	va_start(ap, msg);
181#else
182	va_start(ap);
183	msg = va_arg(ap, char *);
184#endif
185	exverror(EXERROR, msg, ap);
186	va_end(ap);
187}
188
189
190#ifdef __STDC__
191void
192exerror(int cond, char *msg, ...)
193#else
194void
195exerror(va_alist)
196	va_dcl
197#endif
198{
199#ifndef __STDC__
200	int cond;
201	char *msg;
202#endif
203	va_list ap;
204#ifdef __STDC__
205	va_start(ap, msg);
206#else
207	va_start(ap);
208	cond = va_arg(ap, int);
209	msg = va_arg(ap, char *);
210#endif
211	exverror(cond, msg, ap);
212	va_end(ap);
213}
214
215
216
217/*
218 * Table of error messages.
219 */
220
221struct errname {
222	short errcode;		/* error number */
223	short action;		/* operation which encountered the error */
224	char *msg;		/* text describing the error */
225};
226
227
228#define ALL (E_OPEN|E_CREAT|E_EXEC)
229
230STATIC const struct errname errormsg[] = {
231	{ EINTR,	ALL,	"interrupted" },
232	{ EACCES,	ALL,	"permission denied" },
233	{ EIO,		ALL,	"I/O error" },
234	{ ENOENT,	E_OPEN,	"no such file" },
235	{ ENOENT,	E_CREAT,"directory nonexistent" },
236	{ ENOENT,	E_EXEC,	"not found" },
237	{ ENOTDIR,	E_OPEN,	"no such file" },
238	{ ENOTDIR,	E_CREAT,"directory nonexistent" },
239	{ ENOTDIR,	E_EXEC,	"not found" },
240	{ EISDIR,	ALL,	"is a directory" },
241#ifdef notdef
242	{ EMFILE,	ALL,	"too many open files" },
243#endif
244	{ ENFILE,	ALL,	"file table overflow" },
245	{ ENOSPC,	ALL,	"file system full" },
246#ifdef EDQUOT
247	{ EDQUOT,	ALL,	"disk quota exceeded" },
248#endif
249#ifdef ENOSR
250	{ ENOSR,	ALL,	"no streams resources" },
251#endif
252	{ ENXIO,	ALL,	"no such device or address" },
253	{ EROFS,	ALL,	"read-only file system" },
254	{ ETXTBSY,	ALL,	"text busy" },
255#ifdef SYSV
256	{ EAGAIN,	E_EXEC,	"not enough memory" },
257#endif
258	{ ENOMEM,	ALL,	"not enough memory" },
259#ifdef ENOLINK
260	{ ENOLINK,	ALL,	"remote access failed" },
261#endif
262#ifdef EMULTIHOP
263	{ EMULTIHOP,	ALL,	"remote access failed" },
264#endif
265#ifdef ECOMM
266	{ ECOMM,	ALL,	"remote access failed" },
267#endif
268#ifdef ESTALE
269	{ ESTALE,	ALL,	"remote access failed" },
270#endif
271#ifdef ETIMEDOUT
272	{ ETIMEDOUT,	ALL,	"remote access failed" },
273#endif
274#ifdef ELOOP
275	{ ELOOP,	ALL,	"symbolic link loop" },
276#endif
277	{ E2BIG,	E_EXEC,	"argument list too long" },
278#ifdef ELIBACC
279	{ ELIBACC,	E_EXEC,	"shared library missing" },
280#endif
281	{ 0,		0,	NULL },
282};
283
284
285/*
286 * Return a string describing an error.  The returned string may be a
287 * pointer to a static buffer that will be overwritten on the next call.
288 * Action describes the operation that got the error.
289 */
290
291char *
292errmsg(e, action)
293	int e;
294	int action;
295{
296	struct errname const *ep;
297	static char buf[12];
298
299	for (ep = errormsg ; ep->errcode ; ep++) {
300		if (ep->errcode == e && (ep->action & action) != 0)
301			return ep->msg;
302	}
303	fmtstr(buf, sizeof buf, "error %d", e);
304	return buf;
305}
306