misc/error.c

   1 /* Error handler for noninteractive utilities
   2    Copyright (C) 1990-1998, 2000-2004, 2005 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 /* Written by David MacKenzie <djm@gnu.ai.mit.edu>.  */
  21
  22 #ifdef HAVE_CONFIG_H
  23 # include <config.h>
  24 #endif
  25
  26 #include <stdio.h>
  27 #include <libintl.h>
  28 #ifdef _LIBC
  29 # include <wchar.h>
  30 # define mbsrtowcs __mbsrtowcs
  31 #endif
  32
  33 #if HAVE_VPRINTF || HAVE_DOPRNT || _LIBC
  34 # if __STDC__
  35 #  include <stdarg.h>
  36 #  define VA_START(args, lastarg) va_start(args, lastarg)
  37 # else
  38 #  include <varargs.h>
  39 #  define VA_START(args, lastarg) va_start(args)
  40 # endif
  41 #else
  42 # define va_alist a1, a2, a3, a4, a5, a6, a7, a8
  43 # define va_dcl char *a1, *a2, *a3, *a4, *a5, *a6, *a7, *a8;
  44 #endif
  45
  46 #if STDC_HEADERS || _LIBC
  47 # include <stdlib.h>
  48 # include <string.h>
  49 #else
  50 void exit ();
  51 #endif
  52
  53 #include "error.h"
  54
  55 #ifndef _
  56 # define _(String) String
  57 #endif
  58
  59 /* If NULL, error will flush stdout, then print on stderr the program
  60    name, a colon and a space.  Otherwise, error will call this
  61    function without parameters instead.  */
  62 void (*error_print_progname) (
  63 #if __STDC__ - 0
  64                               void
  65 #endif
  66                               );
  67
  68 /* This variable is incremented each time `error' is called.  */
  69 unsigned int error_message_count;
  70
  71 #ifdef _LIBC
  72 /* In the GNU C library, there is a predefined variable for this.  */
  73
  74 # define program_name program_invocation_name
  75 # include <errno.h>
  76 # include <limits.h>
  77 # include <libio/libioP.h>
  78
  79 /* In GNU libc we want do not want to use the common name `error' directly.
  80    Instead make it a weak alias.  */
  81 extern void __error (int status, int errnum, const char *message, ...)
  82      __attribute__ ((__format__ (__printf__, 3, 4)));
  83 extern void __error_at_line (int status, int errnum, const char *file_name,
  84                              unsigned int line_number, const char *message,
  85                              ...)
  86      __attribute__ ((__format__ (__printf__, 5, 6)));;
  87 # define error __error
  88 # define error_at_line __error_at_line
  89
  90 # include <libio/iolibio.h>
  91 # define fflush(s) INTUSE(_IO_fflush) (s)
  92 # undef putc
  93 # define putc(c, fp) INTUSE(_IO_putc) (c, fp)
  94
  95 # include <bits/libc-lock.h>
  96
  97 #else /* not _LIBC */
  98
  99 # if !HAVE_DECL_STRERROR_R && STRERROR_R_CHAR_P
 100 #  ifndef HAVE_DECL_STRERROR_R
 101 "this configure-time declaration test was not run"
 102 #  endif
 103 char *strerror_r ();
 104 # endif
 105
 106 /* The calling program should define program_name and set it to the
 107    name of the executing program.  */
 108 extern char *program_name;
 109
 110 # if HAVE_STRERROR_R || defined strerror_r
 111 #  define __strerror_r strerror_r
 112 # else
 113 #  if HAVE_STRERROR
 114 #   ifndef HAVE_DECL_STRERROR
 115 "this configure-time declaration test was not run"
 116 #   endif
 117 #   if !HAVE_DECL_STRERROR
 118 char *strerror ();
 119 #   endif
 120 #  else
 121 static char *
 122 private_strerror (int errnum)
 123 {
 124   extern char *sys_errlist[];
 125   extern int sys_nerr;
 126
 127   if (errnum > 0 && errnum <= sys_nerr)
 128     return _(sys_errlist[errnum]);
 129   return _("Unknown system error");
 130 }
 131 #   define strerror private_strerror
 132 #  endif /* HAVE_STRERROR */
 133 # endif /* HAVE_STRERROR_R || defined strerror_r */
 134 #endif  /* not _LIBC */
 135
 136 static void
 137 print_errno_message (int errnum)
 138 {
 139   char const *s;
 140
 141 #if defined HAVE_STRERROR_R || _LIBC
 142   char errbuf[1024];
 143 # if STRERROR_R_CHAR_P || _LIBC
 144   s = __strerror_r (errnum, errbuf, sizeof errbuf);
 145 # else
 146   if (__strerror_r (errnum, errbuf, sizeof errbuf) == 0)
 147     s = errbuf;
 148   else
 149     s = 0;
 150 # endif
 151 #else
 152   s = strerror (errnum);
 153 #endif
 154
 155 #if !_LIBC
 156   if (! s)
 157     s = _("Unknown system error");
 158 #endif
 159
 160 #if _LIBC
 161   __fxprintf (NULL, ": %s", L": %s", s);
 162 #else
 163   fprintf (stderr, ": %s", s);
 164 #endif
 165 }
 166
 167 #ifdef VA_START
 168 static void
 169 error_tail (int status, int errnum, const char *message, va_list args)
 170 {
 171 # if HAVE_VPRINTF || _LIBC
 172 #  if _LIBC
 173   if (_IO_fwide (stderr, 0) > 0)
 174     {
 175 #   define ALLOCA_LIMIT 2000
 176       size_t len = strlen (message) + 1;
 177       wchar_t *wmessage = NULL;
 178       mbstate_t st;
 179       size_t res;
 180       const char *tmp;
 181       bool use_malloc = false;
 182
 183       while (1)
 184         {
 185           if (__libc_use_alloca (len * sizeof (wchar_t)))
 186             wmessage = (wchar_t *) alloca (len * sizeof (wchar_t));
 187           else
 188             {
 189               if (!use_malloc)
 190                 wmessage = NULL;
 191
 192               wchar_t *p = (wchar_t *) realloc (wmessage,
 193                                                 len * sizeof (wchar_t));
 194               if (p == NULL)
 195                 {
 196                   free (wmessage);
 197                   fputws_unlocked (L"out of memory\n", stderr);
 198                   return;
 199                 }
 200               wmessage = p;
 201               use_malloc = true;
 202             }
 203
 204           memset (&st, '\0', sizeof (st));
 205           tmp = message;
 206
 207           res = mbsrtowcs (wmessage, &tmp, len, &st);
 208           if (res != len)
 209             break;
 210
 211           if (__builtin_expect (len >= SIZE_MAX / 2, 0))
 212             {
 213               /* This reallyy should not happen if everything is fine.  */
 214               res = (size_t) -1;
 215               break;
 216             }
 217
 218           len *= 2;
 219         }
 220
 221       if (res == (size_t) -1)
 222         {
 223           /* The string cannot be converted.  */
 224           if (use_malloc)
 225             free (wmessage);
 226           wmessage = (wchar_t *) L"???";
 227         }
 228
 229       __vfwprintf (stderr, wmessage, args);
 230
 231       if (use_malloc)
 232         free (wmessage);
 233     }
 234   else
 235 #  endif
 236     vfprintf (stderr, message, args);
 237 # else
 238   _doprnt (message, args, stderr);
 239 # endif
 240   va_end (args);
 241
 242   ++error_message_count;
 243   if (errnum)
 244     print_errno_message (errnum);
 245 # if _LIBC
 246   __fxprintf (NULL, "\n", L"\n");
 247 # else
 248   putc ('\n', stderr);
 249 # endif
 250   fflush (stderr);
 251   if (status)
 252     exit (status);
 253 }
 254 #endif
 255
 256
 257 /* Print the program name and error message MESSAGE, which is a printf-style
 258    format string with optional args.
 259    If ERRNUM is nonzero, print its corresponding system error message.
 260    Exit with status STATUS if it is nonzero.  */
 261 /* VARARGS */
 262 void
 263 #if defined VA_START && __STDC__
 264 error (int status, int errnum, const char *message, ...)
 265 #else
 266 error (status, errnum, message, va_alist)
 267      int status;
 268      int errnum;
 269      char *message;
 270      va_dcl
 271 #endif
 272 {
 273 #ifdef VA_START
 274   va_list args;
 275 #endif
 276
 277 #if defined _LIBC && defined __libc_ptf_call
 278   /* We do not want this call to be cut short by a thread
 279      cancellation.  Therefore disable cancellation for now.  */
 280   int state = PTHREAD_CANCEL_ENABLE;
 281   __libc_ptf_call (pthread_setcancelstate, (PTHREAD_CANCEL_DISABLE, &state),
 282                    0);
 283 #endif
 284
 285   fflush (stdout);
 286 #ifdef _LIBC
 287   _IO_flockfile (stderr);
 288 #endif
 289   if (error_print_progname)
 290     (*error_print_progname) ();
 291   else
 292     {
 293 #if _LIBC
 294       __fxprintf (NULL, "%s: ", L"%s: ", program_name);
 295 #else
 296       fprintf (stderr, "%s: ", program_name);
 297 #endif
 298     }
 299
 300 #ifdef VA_START
 301   VA_START (args, message);
 302   error_tail (status, errnum, message, args);
 303 #else
 304   fprintf (stderr, message, a1, a2, a3, a4, a5, a6, a7, a8);
 305
 306   ++error_message_count;
 307   if (errnum)
 308     print_errno_message (errnum);
 309   putc ('\n', stderr);
 310   fflush (stderr);
 311   if (status)
 312     exit (status);
 313 #endif
 314
 315 #ifdef _LIBC
 316   _IO_funlockfile (stderr);
 317 # ifdef __libc_ptf_call
 318   __libc_ptf_call (pthread_setcancelstate, (state, NULL), 0);
 319 # endif
 320 #endif
 321 }
 322 \f
 323 /* Sometimes we want to have at most one error per line.  This
 324    variable controls whether this mode is selected or not.  */
 325 int error_one_per_line;
 326
 327 void
 328 #if defined VA_START && __STDC__
 329 error_at_line (int status, int errnum, const char *file_name,
 330                unsigned int line_number, const char *message, ...)
 331 #else
 332 error_at_line (status, errnum, file_name, line_number, message, va_alist)
 333      int status;
 334      int errnum;
 335      const char *file_name;
 336      unsigned int line_number;
 337      char *message;
 338      va_dcl
 339 #endif
 340 {
 341 #ifdef VA_START
 342   va_list args;
 343 #endif
 344
 345   if (error_one_per_line)
 346     {
 347       static const char *old_file_name;
 348       static unsigned int old_line_number;
 349
 350       if (old_line_number == line_number
 351           && (file_name == old_file_name
 352               || strcmp (old_file_name, file_name) == 0))
 353         /* Simply return and print nothing.  */
 354         return;
 355
 356       old_file_name = file_name;
 357       old_line_number = line_number;
 358     }
 359
 360 #if defined _LIBC && defined __libc_ptf_call
 361   /* We do not want this call to be cut short by a thread
 362      cancellation.  Therefore disable cancellation for now.  */
 363   int state = PTHREAD_CANCEL_ENABLE;
 364   __libc_ptf_call (pthread_setcancelstate, (PTHREAD_CANCEL_DISABLE, &state),
 365                    0);
 366 #endif
 367
 368   fflush (stdout);
 369 #ifdef _LIBC
 370   _IO_flockfile (stderr);
 371 #endif
 372   if (error_print_progname)
 373     (*error_print_progname) ();
 374   else
 375     {
 376 #if _LIBC
 377       __fxprintf (NULL, "%s:", L"%s: ", program_name);
 378 #else
 379       fprintf (stderr, "%s:", program_name);
 380 #endif
 381     }
 382
 383   if (file_name != NULL)
 384     {
 385 #if _LIBC
 386       __fxprintf (NULL, "%s:%d: ", L"%s:%d: ", file_name, line_number);
 387 #else
 388       fprintf (stderr, "%s:%d: ", file_name, line_number);
 389 #endif
 390     }
 391
 392 #ifdef VA_START
 393   VA_START (args, message);
 394   error_tail (status, errnum, message, args);
 395 #else
 396   fprintf (stderr, message, a1, a2, a3, a4, a5, a6, a7, a8);
 397
 398   ++error_message_count;
 399   if (errnum)
 400     print_errno_message (errnum);
 401   putc ('\n', stderr);
 402   fflush (stderr);
 403   if (status)
 404     exit (status);
 405 #endif
 406
 407 #ifdef _LIBC
 408   _IO_funlockfile (stderr);
 409 # ifdef __libc_ptf_call
 410   __libc_ptf_call (pthread_setcancelstate, (state, NULL), 0);
 411 # endif
 412 #endif
 413 }
 414
 415 #ifdef _LIBC
 416 /* Make the weak alias.  */
 417 # undef error
 418 # undef error_at_line
 419 weak_alias (__error, error)
 420 weak_alias (__error_at_line, error_at_line)
 421 #endif