xref: /netbsd-src/bin/sh/error.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*	$NetBSD: error.c,v 1.41 2017/07/24 12:35:12 kre Exp $	*/
2 
3 /*-
4  * Copyright (c) 1991, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Kenneth Almquist.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include <sys/cdefs.h>
36 #ifndef lint
37 #if 0
38 static char sccsid[] = "@(#)error.c	8.2 (Berkeley) 5/4/95";
39 #else
40 __RCSID("$NetBSD: error.c,v 1.41 2017/07/24 12:35:12 kre Exp $");
41 #endif
42 #endif /* not lint */
43 
44 /*
45  * Errors and exceptions.
46  */
47 
48 #include <signal.h>
49 #include <stdlib.h>
50 #include <unistd.h>
51 #include <errno.h>
52 #include <stdio.h>
53 #include <string.h>
54 
55 #include "shell.h"
56 #include "eval.h" /* for commandname */
57 #include "main.h"
58 #include "options.h"
59 #include "output.h"
60 #include "error.h"
61 #include "show.h"
62 
63 
64 /*
65  * Code to handle exceptions in C.
66  */
67 
68 struct jmploc *handler;
69 int exception;
70 volatile int suppressint;
71 volatile int intpending;
72 
73 
74 static void exverror(int, const char *, va_list) __dead;
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.  The call to _exit is necessary because
97  * there is a short period after a fork before the signal handlers are
98  * set to the appropriate value for the child.  (The test for iflag is
99  * just defensive programming.)
100  */
101 
102 void
103 onint(void)
104 {
105 	sigset_t nsigset;
106 
107 	if (suppressint) {
108 		intpending = 1;
109 		return;
110 	}
111 	intpending = 0;
112 	sigemptyset(&nsigset);
113 	sigprocmask(SIG_SETMASK, &nsigset, NULL);
114 	if (rootshell && iflag)
115 		exraise(EXINT);
116 	else {
117 		signal(SIGINT, SIG_DFL);
118 		raise(SIGINT);
119 	}
120 	/* NOTREACHED */
121 }
122 
123 static __printflike(2, 0) void
124 exvwarning(int sv_errno, const char *msg, va_list ap)
125 {
126 	/* Partially emulate line buffered output so that:
127 	 *	printf '%d\n' 1 a 2
128 	 * and
129 	 *	printf '%d %d %d\n' 1 a 2
130 	 * both generate sensible text when stdout and stderr are merged.
131 	 */
132 	if (output.buf != NULL && output.nextc != output.buf &&
133 	    output.nextc[-1] == '\n')
134 		flushout(&output);
135 	if (commandname)
136 		outfmt(&errout, "%s: ", commandname);
137 	else
138 		outfmt(&errout, "%s: ", getprogname());
139 	if (msg != NULL) {
140 		doformat(&errout, msg, ap);
141 		if (sv_errno >= 0)
142 			outfmt(&errout, ": ");
143 	}
144 	if (sv_errno >= 0)
145 		outfmt(&errout, "%s", strerror(sv_errno));
146 	out2c('\n');
147 	flushout(&errout);
148 }
149 
150 /*
151  * Exverror is called to raise the error exception.  If the second argument
152  * is not NULL then error prints an error message using printf style
153  * formatting.  It then raises the error exception.
154  */
155 static __printflike(2, 0) void
156 exverror(int cond, const char *msg, va_list ap)
157 {
158 	CLEAR_PENDING_INT;
159 	INTOFF;
160 
161 #ifdef DEBUG
162 	if (msg) {
163 		CTRACE(DBG_ERRS, ("exverror(%d, \"", cond));
164 		CTRACEV(DBG_ERRS, (msg, ap));
165 		CTRACE(DBG_ERRS, ("\") pid=%d\n", getpid()));
166 	} else
167 		CTRACE(DBG_ERRS, ("exverror(%d, NULL) pid=%d\n", cond,
168 		    getpid()));
169 #endif
170 	if (msg)
171 		exvwarning(-1, msg, ap);
172 
173 	flushall();
174 	exraise(cond);
175 	/* NOTREACHED */
176 }
177 
178 
179 void
180 error(const char *msg, ...)
181 {
182 	va_list ap;
183 
184 	/*
185 	 * On error, we certainly never want exit(0)...
186 	 */
187 	if (exerrno == 0)
188 		exerrno = 1;
189 	va_start(ap, msg);
190 	exverror(EXERROR, msg, ap);
191 	/* NOTREACHED */
192 	va_end(ap);
193 }
194 
195 
196 void
197 exerror(int cond, const char *msg, ...)
198 {
199 	va_list ap;
200 
201 	va_start(ap, msg);
202 	exverror(cond, msg, ap);
203 	/* NOTREACHED */
204 	va_end(ap);
205 }
206 
207 /*
208  * error/warning routines for external builtins
209  */
210 
211 void
212 sh_exit(int rval)
213 {
214 	exerrno = rval & 255;
215 	exraise(EXEXEC);
216 }
217 
218 void
219 sh_err(int status, const char *fmt, ...)
220 {
221 	va_list ap;
222 
223 	va_start(ap, fmt);
224 	exvwarning(errno, fmt, ap);
225 	va_end(ap);
226 	sh_exit(status);
227 }
228 
229 void
230 sh_verr(int status, const char *fmt, va_list ap)
231 {
232 	exvwarning(errno, fmt, ap);
233 	sh_exit(status);
234 }
235 
236 void
237 sh_errx(int status, const char *fmt, ...)
238 {
239 	va_list ap;
240 
241 	va_start(ap, fmt);
242 	exvwarning(-1, fmt, ap);
243 	va_end(ap);
244 	sh_exit(status);
245 }
246 
247 void
248 sh_verrx(int status, const char *fmt, va_list ap)
249 {
250 	exvwarning(-1, fmt, ap);
251 	sh_exit(status);
252 }
253 
254 void
255 sh_warn(const char *fmt, ...)
256 {
257 	va_list ap;
258 
259 	va_start(ap, fmt);
260 	exvwarning(errno, fmt, ap);
261 	va_end(ap);
262 }
263 
264 void
265 sh_vwarn(const char *fmt, va_list ap)
266 {
267 	exvwarning(errno, fmt, ap);
268 }
269 
270 void
271 sh_warnx(const char *fmt, ...)
272 {
273 	va_list ap;
274 
275 	va_start(ap, fmt);
276 	exvwarning(-1, fmt, ap);
277 	va_end(ap);
278 }
279 
280 void
281 sh_vwarnx(const char *fmt, va_list ap)
282 {
283 	exvwarning(-1, fmt, ap);
284 }
285 
286 
287 /*
288  * Table of error messages.
289  */
290 
291 struct errname {
292 	short errcode;		/* error number */
293 	short action;		/* operation which encountered the error */
294 	const char *msg;	/* text describing the error */
295 };
296 
297 
298 #define ALL (E_OPEN|E_CREAT|E_EXEC)
299 
300 STATIC const struct errname errormsg[] = {
301 	{ EINTR,	ALL,	"interrupted" },
302 	{ EACCES,	ALL,	"permission denied" },
303 	{ EIO,		ALL,	"I/O error" },
304 	{ EEXIST,	ALL,	"file exists" },
305 	{ ENOENT,	E_OPEN,	"no such file" },
306 	{ ENOENT,	E_CREAT,"directory nonexistent" },
307 	{ ENOENT,	E_EXEC,	"not found" },
308 	{ ENOTDIR,	E_OPEN,	"no such file" },
309 	{ ENOTDIR,	E_CREAT,"directory nonexistent" },
310 	{ ENOTDIR,	E_EXEC,	"not found" },
311 	{ EISDIR,	ALL,	"is a directory" },
312 #ifdef EMFILE
313 	{ EMFILE,	ALL,	"too many open files" },
314 #endif
315 	{ ENFILE,	ALL,	"file table overflow" },
316 	{ ENOSPC,	ALL,	"file system full" },
317 #ifdef EDQUOT
318 	{ EDQUOT,	ALL,	"disk quota exceeded" },
319 #endif
320 #ifdef ENOSR
321 	{ ENOSR,	ALL,	"no streams resources" },
322 #endif
323 	{ ENXIO,	ALL,	"no such device or address" },
324 	{ EROFS,	ALL,	"read-only file system" },
325 	{ ETXTBSY,	ALL,	"text busy" },
326 #ifdef EAGAIN
327 	{ EAGAIN,	E_EXEC,	"not enough memory" },
328 #endif
329 	{ ENOMEM,	ALL,	"not enough memory" },
330 #ifdef ENOLINK
331 	{ ENOLINK,	ALL,	"remote access failed" },
332 #endif
333 #ifdef EMULTIHOP
334 	{ EMULTIHOP,	ALL,	"remote access failed" },
335 #endif
336 #ifdef ECOMM
337 	{ ECOMM,	ALL,	"remote access failed" },
338 #endif
339 #ifdef ESTALE
340 	{ ESTALE,	ALL,	"remote access failed" },
341 #endif
342 #ifdef ETIMEDOUT
343 	{ ETIMEDOUT,	ALL,	"remote access failed" },
344 #endif
345 #ifdef ELOOP
346 	{ ELOOP,	ALL,	"symbolic link loop" },
347 #endif
348 #ifdef ENAMETOOLONG
349 	{ ENAMETOOLONG,	ALL,	"file name too long" },
350 #endif
351 	{ E2BIG,	E_EXEC,	"argument list too long" },
352 #ifdef ELIBACC
353 	{ ELIBACC,	E_EXEC,	"shared library missing" },
354 #endif
355 	{ 0,		0,	NULL },
356 };
357 
358 
359 /*
360  * Return a string describing an error.  The returned string may be a
361  * pointer to a static buffer that will be overwritten on the next call.
362  * Action describes the operation that got the error.
363  */
364 
365 const char *
366 errmsg(int e, int action)
367 {
368 	struct errname const *ep;
369 	static char buf[12];
370 
371 	for (ep = errormsg ; ep->errcode ; ep++) {
372 		if (ep->errcode == e && (ep->action & action) != 0)
373 			return ep->msg;
374 	}
375 	fmtstr(buf, sizeof buf, "error %d", e);
376 	return buf;
377 }
378