bin/sh/error.c

   1 /*      $NetBSD: error.c,v 1.38 2012/03/15 02:02:20 joerg 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 1.38 2012/03/15 02:02:20 joerg 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.nextc != output.buf && output.nextc[-1] == '\n')
 133                 flushout(&output);
 134         if (commandname)
 135                 outfmt(&errout, "%s: ", commandname);
 136         else
 137                 outfmt(&errout, "%s: ", getprogname());
 138         if (msg != NULL) {
 139                 doformat(&errout, msg, ap);
 140                 if (sv_errno >= 0)
 141                         outfmt(&errout, ": ");
 142         }
 143         if (sv_errno >= 0)
 144                 outfmt(&errout, "%s", strerror(sv_errno));
 145         out2c('\n');
 146         flushout(&errout);
 147 }
 148
 149 /*
 150  * Exverror is called to raise the error exception.  If the second argument
 151  * is not NULL then error prints an error message using printf style
 152  * formatting.  It then raises the error exception.
 153  */
 154 static __printflike(2, 0) void
 155 exverror(int cond, const char *msg, va_list ap)
 156 {
 157         CLEAR_PENDING_INT;
 158         INTOFF;
 159
 160 #ifdef DEBUG
 161         if (msg) {
 162                 TRACE(("exverror(%d, \"", cond));
 163                 TRACEV((msg, ap));
 164                 TRACE(("\") pid=%d\n", getpid()));
 165         } else
 166                 TRACE(("exverror(%d, NULL) pid=%d\n", cond, getpid()));
 167 #endif
 168         if (msg)
 169                 exvwarning(-1, msg, ap);
 170
 171         flushall();
 172         exraise(cond);
 173         /* NOTREACHED */
 174 }
 175
 176
 177 void
 178 error(const char *msg, ...)
 179 {
 180         va_list ap;
 181
 182         va_start(ap, msg);
 183         exverror(EXERROR, msg, ap);
 184         /* NOTREACHED */
 185         va_end(ap);
 186 }
 187
 188
 189 void
 190 exerror(int cond, const char *msg, ...)
 191 {
 192         va_list ap;
 193
 194         va_start(ap, msg);
 195         exverror(cond, msg, ap);
 196         /* NOTREACHED */
 197         va_end(ap);
 198 }
 199
 200 /*
 201  * error/warning routines for external builtins
 202  */
 203
 204 void
 205 sh_exit(int rval)
 206 {
 207         exerrno = rval & 255;
 208         exraise(EXEXEC);
 209 }
 210
 211 void
 212 sh_err(int status, const char *fmt, ...)
 213 {
 214         va_list ap;
 215
 216         va_start(ap, fmt);
 217         exvwarning(errno, fmt, ap);
 218         va_end(ap);
 219         sh_exit(status);
 220 }
 221
 222 void
 223 sh_verr(int status, const char *fmt, va_list ap)
 224 {
 225         exvwarning(errno, fmt, ap);
 226         sh_exit(status);
 227 }
 228
 229 void
 230 sh_errx(int status, const char *fmt, ...)
 231 {
 232         va_list ap;
 233
 234         va_start(ap, fmt);
 235         exvwarning(-1, fmt, ap);
 236         va_end(ap);
 237         sh_exit(status);
 238 }
 239
 240 void
 241 sh_verrx(int status, const char *fmt, va_list ap)
 242 {
 243         exvwarning(-1, fmt, ap);
 244         sh_exit(status);
 245 }
 246
 247 void
 248 sh_warn(const char *fmt, ...)
 249 {
 250         va_list ap;
 251
 252         va_start(ap, fmt);
 253         exvwarning(errno, fmt, ap);
 254         va_end(ap);
 255 }
 256
 257 void
 258 sh_vwarn(const char *fmt, va_list ap)
 259 {
 260         exvwarning(errno, fmt, ap);
 261 }
 262
 263 void
 264 sh_warnx(const char *fmt, ...)
 265 {
 266         va_list ap;
 267
 268         va_start(ap, fmt);
 269         exvwarning(-1, fmt, ap);
 270         va_end(ap);
 271 }
 272
 273 void
 274 sh_vwarnx(const char *fmt, va_list ap)
 275 {
 276         exvwarning(-1, fmt, ap);
 277 }
 278
 279
 280 /*
 281  * Table of error messages.
 282  */
 283
 284 struct errname {
 285         short errcode;          /* error number */
 286         short action;           /* operation which encountered the error */
 287         const char *msg;        /* text describing the error */
 288 };
 289
 290
 291 #define ALL (E_OPEN|E_CREAT|E_EXEC)
 292
 293 STATIC const struct errname errormsg[] = {
 294         { EINTR,        ALL,    "interrupted" },
 295         { EACCES,       ALL,    "permission denied" },
 296         { EIO,          ALL,    "I/O error" },
 297         { EEXIST,       ALL,    "file exists" },
 298         { ENOENT,       E_OPEN, "no such file" },
 299         { ENOENT,       E_CREAT,"directory nonexistent" },
 300         { ENOENT,       E_EXEC, "not found" },
 301         { ENOTDIR,      E_OPEN, "no such file" },
 302         { ENOTDIR,      E_CREAT,"directory nonexistent" },
 303         { ENOTDIR,      E_EXEC, "not found" },
 304         { EISDIR,       ALL,    "is a directory" },
 305 #ifdef EMFILE
 306         { EMFILE,       ALL,    "too many open files" },
 307 #endif
 308         { ENFILE,       ALL,    "file table overflow" },
 309         { ENOSPC,       ALL,    "file system full" },
 310 #ifdef EDQUOT
 311         { EDQUOT,       ALL,    "disk quota exceeded" },
 312 #endif
 313 #ifdef ENOSR
 314         { ENOSR,        ALL,    "no streams resources" },
 315 #endif
 316         { ENXIO,        ALL,    "no such device or address" },
 317         { EROFS,        ALL,    "read-only file system" },
 318         { ETXTBSY,      ALL,    "text busy" },
 319 #ifdef EAGAIN
 320         { EAGAIN,       E_EXEC, "not enough memory" },
 321 #endif
 322         { ENOMEM,       ALL,    "not enough memory" },
 323 #ifdef ENOLINK
 324         { ENOLINK,      ALL,    "remote access failed" },
 325 #endif
 326 #ifdef EMULTIHOP
 327         { EMULTIHOP,    ALL,    "remote access failed" },
 328 #endif
 329 #ifdef ECOMM
 330         { ECOMM,        ALL,    "remote access failed" },
 331 #endif
 332 #ifdef ESTALE
 333         { ESTALE,       ALL,    "remote access failed" },
 334 #endif
 335 #ifdef ETIMEDOUT
 336         { ETIMEDOUT,    ALL,    "remote access failed" },
 337 #endif
 338 #ifdef ELOOP
 339         { ELOOP,        ALL,    "symbolic link loop" },
 340 #endif
 341 #ifdef ENAMETOOLONG
 342         { ENAMETOOLONG, ALL,    "file name too long" },
 343 #endif
 344         { E2BIG,        E_EXEC, "argument list too long" },
 345 #ifdef ELIBACC
 346         { ELIBACC,      E_EXEC, "shared library missing" },
 347 #endif
 348         { 0,            0,      NULL },
 349 };
 350
 351
 352 /*
 353  * Return a string describing an error.  The returned string may be a
 354  * pointer to a static buffer that will be overwritten on the next call.
 355  * Action describes the operation that got the error.
 356  */
 357
 358 const char *
 359 errmsg(int e, int action)
 360 {
 361         struct errname const *ep;
 362         static char buf[12];
 363
 364         for (ep = errormsg ; ep->errcode ; ep++) {
 365                 if (ep->errcode == e && (ep->action & action) != 0)
 366                         return ep->msg;
 367         }
 368         fmtstr(buf, sizeof buf, "error %d", e);
 369         return buf;
 370 }