lib/error.c

   1 /* Error handler for noninteractive utilities
   2    Copyright (C) 1990-1998, 2000, 2001 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.  Its master source is NOT part of
   4    the C library, however.  The master source lives in /gd/gnu/lib.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, write to the Free
  18    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19    02111-1307 USA.  */
  20
  21 /* Written by David MacKenzie <djm@gnu.ai.mit.edu>.  */
  22
  23 #ifdef HAVE_CONFIG_H
  24 # include <config.h>
  25 #endif
  26
  27 #include <stdio.h>
  28 #if HAVE_LIBINTL_H
  29 # include <libintl.h>
  30 #endif
  31 #ifdef _LIBC
  32 # include <wchar.h>
  33 # define mbsrtowcs __mbsrtowcs
  34 #endif
  35
  36 #if HAVE_VPRINTF || HAVE_DOPRNT || _LIBC
  37 # if __STDC__
  38 #  include <stdarg.h>
  39 #  define VA_START(args, lastarg) va_start(args, lastarg)
  40 # else
  41 #  include <varargs.h>
  42 #  define VA_START(args, lastarg) va_start(args)
  43 # endif
  44 #else
  45 # define va_alist a1, a2, a3, a4, a5, a6, a7, a8
  46 # define va_dcl char *a1, *a2, *a3, *a4, *a5, *a6, *a7, *a8;
  47 #endif
  48
  49 #if STDC_HEADERS || _LIBC
  50 # include <stdlib.h>
  51 # include <string.h>
  52 #else
  53 void exit ();
  54 #endif
  55
  56 #include "error.h"
  57 #include "unlocked-io.h"
  58
  59 #ifndef _
  60 # define _(String) String
  61 #endif
  62
  63 /* If NULL, error will flush stdout, then print on stderr the program
  64    name, a colon and a space.  Otherwise, error will call this
  65    function without parameters instead.  */
  66 void (*error_print_progname) (
  67 #if __STDC__ - 0
  68                               void
  69 #endif
  70                               );
  71
  72 /* This variable is incremented each time `error' is called.  */
  73 unsigned int error_message_count;
  74
  75 #ifdef _LIBC
  76 /* In the GNU C library, there is a predefined variable for this.  */
  77
  78 # define program_name program_invocation_name
  79 # include <errno.h>
  80
  81 /* In GNU libc we want do not want to use the common name `error' directly.
  82    Instead make it a weak alias.  */
  83 extern void __error (int status, int errnum, const char *message, ...)
  84      __attribute__ ((__format__ (__printf__, 3, 4)));
  85 extern void __error_at_line (int status, int errnum, const char *file_name,
  86                              unsigned int line_number, const char *message,
  87                              ...)
  88      __attribute__ ((__format__ (__printf__, 5, 6)));;
  89 # define error __error
  90 # define error_at_line __error_at_line
  91
  92 # ifdef USE_IN_LIBIO
  93 #  include <libio/iolibio.h>
  94 #  define fflush(s) _IO_fflush (s)
  95 # endif
  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 && USE_IN_LIBIO
 161   if (_IO_fwide (stderr, 0) > 0)
 162     {
 163       __fwprintf (stderr, L": %s", s);
 164       return;
 165     }
 166 #endif
 167
 168   fprintf (stderr, ": %s", s);
 169 }
 170
 171 #ifdef VA_START
 172 static void
 173 error_tail (int status, int errnum, const char *message, va_list args)
 174 {
 175 # if HAVE_VPRINTF || _LIBC
 176 #  if _LIBC && USE_IN_LIBIO
 177   if (_IO_fwide (stderr, 0) > 0)
 178     {
 179 #   define ALLOCA_LIMIT 2000
 180       size_t len = strlen (message) + 1;
 181       wchar_t *wmessage = NULL;
 182       mbstate_t st;
 183       size_t res;
 184       const char *tmp;
 185
 186       do
 187         {
 188           if (len < ALLOCA_LIMIT)
 189             wmessage = (wchar_t *) alloca (len * sizeof (wchar_t));
 190           else
 191             {
 192               if (wmessage != NULL && len / 2 < ALLOCA_LIMIT)
 193                 wmessage = NULL;
 194
 195               wmessage = (wchar_t *) realloc (wmessage,
 196                                               len * sizeof (wchar_t));
 197
 198               if (wmessage == NULL)
 199                 {
 200                   fputws_unlocked (L"out of memory\n", stderr);
 201                   return;
 202                 }
 203             }
 204
 205           memset (&st, '\0', sizeof (st));
 206           tmp =message;
 207         }
 208       while ((res = mbsrtowcs (wmessage, &tmp, len, &st)) == len);
 209
 210       if (res == (size_t) -1)
 211         /* The string cannot be converted.  */
 212         wmessage = (wchar_t *) L"???";
 213
 214       __vfwprintf (stderr, wmessage, args);
 215     }
 216   else
 217 #  endif
 218     vfprintf (stderr, message, args);
 219 # else
 220   _doprnt (message, args, stderr);
 221 # endif
 222   va_end (args);
 223
 224   ++error_message_count;
 225   if (errnum)
 226     print_errno_message (errnum);
 227 # if _LIBC && USE_IN_LIBIO
 228   if (_IO_fwide (stderr, 0) > 0)
 229     putwc (L'\n', stderr);
 230   else
 231 # endif
 232     putc ('\n', stderr);
 233   fflush (stderr);
 234   if (status)
 235     exit (status);
 236 }
 237 #endif
 238
 239
 240 /* Print the program name and error message MESSAGE, which is a printf-style
 241    format string with optional args.
 242    If ERRNUM is nonzero, print its corresponding system error message.
 243    Exit with status STATUS if it is nonzero.  */
 244 /* VARARGS */
 245 void
 246 #if defined VA_START && __STDC__
 247 error (int status, int errnum, const char *message, ...)
 248 #else
 249 error (status, errnum, message, va_alist)
 250      int status;
 251      int errnum;
 252      char *message;
 253      va_dcl
 254 #endif
 255 {
 256 #ifdef VA_START
 257   va_list args;
 258 #endif
 259
 260   fflush (stdout);
 261 #ifdef _LIBC
 262 # ifdef USE_IN_LIBIO
 263   _IO_flockfile (stderr);
 264 # else
 265   __flockfile (stderr);
 266 # endif
 267 #endif
 268   if (error_print_progname)
 269     (*error_print_progname) ();
 270   else
 271     {
 272 #if _LIBC && USE_IN_LIBIO
 273       if (_IO_fwide (stderr, 0) > 0)
 274         __fwprintf (stderr, L"%s: ", program_name);
 275       else
 276 #endif
 277         fprintf (stderr, "%s: ", program_name);
 278     }
 279
 280 #ifdef VA_START
 281   VA_START (args, message);
 282   error_tail (status, errnum, message, args);
 283 #else
 284   fprintf (stderr, message, a1, a2, a3, a4, a5, a6, a7, a8);
 285
 286   ++error_message_count;
 287   if (errnum)
 288     print_errno_message (errnum);
 289   putc ('\n', stderr);
 290   fflush (stderr);
 291   if (status)
 292     exit (status);
 293 #endif
 294
 295 #ifdef _LIBC
 296 # ifdef USE_IN_LIBIO
 297   _IO_funlockfile (stderr);
 298 # else
 299   __funlockfile (stderr);
 300 # endif
 301 #endif
 302 }
 303 \f
 304 /* Sometimes we want to have at most one error per line.  This
 305    variable controls whether this mode is selected or not.  */
 306 int error_one_per_line;
 307
 308 void
 309 #if defined VA_START && __STDC__
 310 error_at_line (int status, int errnum, const char *file_name,
 311                unsigned int line_number, const char *message, ...)
 312 #else
 313 error_at_line (status, errnum, file_name, line_number, message, va_alist)
 314      int status;
 315      int errnum;
 316      const char *file_name;
 317      unsigned int line_number;
 318      char *message;
 319      va_dcl
 320 #endif
 321 {
 322 #ifdef VA_START
 323   va_list args;
 324 #endif
 325
 326   if (error_one_per_line)
 327     {
 328       static const char *old_file_name;
 329       static unsigned int old_line_number;
 330
 331       if (old_line_number == line_number
 332           && (file_name == old_file_name
 333               || strcmp (old_file_name, file_name) == 0))
 334         /* Simply return and print nothing.  */
 335         return;
 336
 337       old_file_name = file_name;
 338       old_line_number = line_number;
 339     }
 340
 341   fflush (stdout);
 342 #ifdef _LIBC
 343 # ifdef USE_IN_LIBIO
 344   _IO_flockfile (stderr);
 345 # else
 346   __flockfile (stderr);
 347 # endif
 348 #endif
 349   if (error_print_progname)
 350     (*error_print_progname) ();
 351   else
 352     {
 353 #if _LIBC && USE_IN_LIBIO
 354       if (_IO_fwide (stderr, 0) > 0)
 355         __fwprintf (stderr, L"%s: ", program_name);
 356       else
 357 #endif
 358         fprintf (stderr, "%s:", program_name);
 359     }
 360
 361   if (file_name != NULL)
 362     {
 363 #if _LIBC && USE_IN_LIBIO
 364       if (_IO_fwide (stderr, 0) > 0)
 365         __fwprintf (stderr, L"%s:%d: ", file_name, line_number);
 366       else
 367 #endif
 368         fprintf (stderr, "%s:%d: ", file_name, line_number);
 369     }
 370
 371 #ifdef VA_START
 372   VA_START (args, message);
 373   error_tail (status, errnum, message, args);
 374 #else
 375   fprintf (stderr, message, a1, a2, a3, a4, a5, a6, a7, a8);
 376
 377   ++error_message_count;
 378   if (errnum)
 379     print_errno_message (errnum);
 380   putc ('\n', stderr);
 381   fflush (stderr);
 382   if (status)
 383     exit (status);
 384 #endif
 385
 386 #ifdef _LIBC
 387 # ifdef USE_IN_LIBIO
 388   _IO_funlockfile (stderr);
 389 # else
 390   __funlockfile (stderr);
 391 # endif
 392 #endif
 393 }
 394
 395 #ifdef _LIBC
 396 /* Make the weak alias.  */
 397 # undef error
 398 # undef error_at_line
 399 weak_alias (__error, error)
 400 weak_alias (__error_at_line, error_at_line)
 401 #endif