error.c revision 78732 
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 78732 2001-06-24 23:04:23Z dd $";
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
67struct jmploc *handler;
68volatile sig_atomic_t exception;
69volatile sig_atomic_t suppressint;
70volatile sig_atomic_t intpending;
71char *commandname;
72
73
74static 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
82void
83exraise(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
103void
104onint() {
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 */
142static void
143exverror(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__
169void
170error(const char *msg, ...)
171#else
172void
173error(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__
193void
194exerror(int cond, const char *msg, ...)
195#else
196void
197exerror(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
223struct 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
232STATIC 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
293char *
294errmsg(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