xref: /freebsd/bin/sh/error.c (revision ae83180158c4c937f170e31eff311b18c0286a93)
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 #endif /* not lint */
42 #include <sys/cdefs.h>
43 __FBSDID("$FreeBSD$");
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(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(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 
102 void
103 onint(void)
104 {
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(int cond, const char *msg, va_list ap)
144 {
145 	CLEAR_PENDING_INT;
146 	INTOFF;
147 
148 #ifdef DEBUG
149 	if (msg)
150 		TRACE(("exverror(%d, \"%s\") pid=%d\n", cond, msg, getpid()));
151 	else
152 		TRACE(("exverror(%d, NULL) pid=%d\n", cond, getpid()));
153 #endif
154 	if (msg) {
155 		if (commandname)
156 			outfmt(&errout, "%s: ", commandname);
157 		doformat(&errout, msg, ap);
158 		out2c('\n');
159 	}
160 	flushall();
161 	exraise(cond);
162 }
163 
164 
165 void
166 error(const char *msg, ...)
167 {
168 	va_list ap;
169 	va_start(ap, msg);
170 	exverror(EXERROR, msg, ap);
171 	va_end(ap);
172 }
173 
174 
175 void
176 exerror(int cond, const char *msg, ...)
177 {
178 	va_list ap;
179 	va_start(ap, msg);
180 	exverror(cond, msg, ap);
181 	va_end(ap);
182 }
183 
184 
185 
186 /*
187  * Table of error messages.
188  */
189 
190 struct errname {
191 	short errcode;		/* error number */
192 	short action;		/* operation which encountered the error */
193 	char *msg;		/* text describing the error */
194 };
195 
196 
197 #define ALL (E_OPEN|E_CREAT|E_EXEC)
198 
199 STATIC const struct errname errormsg[] = {
200 	{ EINTR,	ALL,	"interrupted" },
201 	{ EACCES,	ALL,	"permission denied" },
202 	{ EIO,		ALL,	"I/O error" },
203 	{ ENOENT,	E_OPEN,	"no such file" },
204 	{ ENOENT,	E_CREAT,"directory nonexistent" },
205 	{ ENOENT,	E_EXEC,	"not found" },
206 	{ ENOTDIR,	E_OPEN,	"no such file" },
207 	{ ENOTDIR,	E_CREAT,"directory nonexistent" },
208 	{ ENOTDIR,	E_EXEC,	"not found" },
209 	{ EISDIR,	ALL,	"is a directory" },
210 #ifdef notdef
211 	{ EMFILE,	ALL,	"too many open files" },
212 #endif
213 	{ ENFILE,	ALL,	"file table overflow" },
214 	{ ENOSPC,	ALL,	"filesystem full" },
215 #ifdef EDQUOT
216 	{ EDQUOT,	ALL,	"disk quota exceeded" },
217 #endif
218 #ifdef ENOSR
219 	{ ENOSR,	ALL,	"no streams resources" },
220 #endif
221 	{ ENXIO,	ALL,	"no such device or address" },
222 	{ EROFS,	ALL,	"read-only filesystem" },
223 	{ ETXTBSY,	ALL,	"text busy" },
224 	{ ENOMEM,	ALL,	"not enough memory" },
225 #ifdef ENOLINK
226 	{ ENOLINK,	ALL,	"remote access failed" },
227 #endif
228 #ifdef EMULTIHOP
229 	{ EMULTIHOP,	ALL,	"remote access failed" },
230 #endif
231 #ifdef ECOMM
232 	{ ECOMM,	ALL,	"remote access failed" },
233 #endif
234 #ifdef ESTALE
235 	{ ESTALE,	ALL,	"remote access failed" },
236 #endif
237 #ifdef ETIMEDOUT
238 	{ ETIMEDOUT,	ALL,	"remote access failed" },
239 #endif
240 #ifdef ELOOP
241 	{ ELOOP,	ALL,	"symbolic link loop" },
242 #endif
243 	{ E2BIG,	E_EXEC,	"argument list too long" },
244 #ifdef ELIBACC
245 	{ ELIBACC,	E_EXEC,	"shared library missing" },
246 #endif
247 	{ EEXIST,	E_CREAT, "file exists" },
248 	{ 0,		0,	NULL },
249 };
250 
251 
252 /*
253  * Return a string describing an error.  The returned string may be a
254  * pointer to a static buffer that will be overwritten on the next call.
255  * Action describes the operation that got the error.
256  */
257 
258 char *
259 errmsg(int e, int action)
260 {
261 	struct errname const *ep;
262 	static char buf[12];
263 
264 	for (ep = errormsg ; ep->errcode ; ep++) {
265 		if (ep->errcode == e && (ep->action & action) != 0)
266 			return ep->msg;
267 	}
268 	fmtstr(buf, sizeof buf, "error %d", e);
269 	return buf;
270 }
271