contrib/diffutils-2.8.1/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    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2, or (at your option)
   9    any later version.
  10
  11    This program 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
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software Foundation,
  18    Inc., 59 Temple Place - Suite 330, Boston, MA 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 #if HAVE_LIBINTL_H
  28 # include <libintl.h>
  29 #endif
  30 #ifdef _LIBC
  31 # include <wchar.h>
  32 # define mbsrtowcs __mbsrtowcs
  33 #endif
  34
  35 #if HAVE_VPRINTF || HAVE_DOPRNT || _LIBC
  36 # if __STDC__
  37 #  include <stdarg.h>
  38 #  define VA_START(args, lastarg) va_start(args, lastarg)
  39 # else
  40 #  include <varargs.h>
  41 #  define VA_START(args, lastarg) va_start(args)
  42 # endif
  43 #else
  44 # define va_alist a1, a2, a3, a4, a5, a6, a7, a8
  45 # define va_dcl char *a1, *a2, *a3, *a4, *a5, *a6, *a7, *a8;
  46 #endif
  47
  48 #if STDC_HEADERS || _LIBC
  49 # include <stdlib.h>
  50 # include <string.h>
  51 #else
  52 void exit ();
  53 #endif
  54
  55 #include "error.h"
  56 #include "unlocked-io.h"
  57
  58 #ifndef _
  59 # define _(String) String
  60 #endif
  61
  62 /* If NULL, error will flush stdout, then print on stderr the program
  63    name, a colon and a space.  Otherwise, error will call this
  64    function without parameters instead.  */
  65 void (*error_print_progname) (
  66 #if __STDC__ - 0
  67                               void
  68 #endif
  69                               );
  70
  71 /* This variable is incremented each time `error' is called.  */
  72 unsigned int error_message_count;
  73
  74 #ifdef _LIBC
  75 /* In the GNU C library, there is a predefined variable for this.  */
  76
  77 # define program_name program_invocation_name
  78 # include <errno.h>
  79
  80 /* In GNU libc we want do not want to use the common name `error' directly.
  81    Instead make it a weak alias.  */
  82 extern void __error (int status, int errnum, const char *message, ...)
  83      __attribute__ ((__format__ (__printf__, 3, 4)));
  84 extern void __error_at_line (int status, int errnum, const char *file_name,
  85                              unsigned int line_number, const char *message,
  86                              ...)
  87      __attribute__ ((__format__ (__printf__, 5, 6)));;
  88 # define error __error
  89 # define error_at_line __error_at_line
  90
  91 # ifdef USE_IN_LIBIO
  92 #  include <libio/iolibio.h>
  93 #  define fflush(s) _IO_fflush (s)
  94 # endif
  95
  96 #else /* not _LIBC */
  97
  98 # if !HAVE_DECL_STRERROR_R && STRERROR_R_CHAR_P
  99 #  ifndef HAVE_DECL_STRERROR_R
 100 "this configure-time declaration test was not run"
 101 #  endif
 102 char *strerror_r ();
 103 # endif
 104
 105 /* The calling program should define program_name and set it to the
 106    name of the executing program.  */
 107 extern char *program_name;
 108
 109 # if HAVE_STRERROR_R || defined strerror_r
 110 #  define __strerror_r strerror_r
 111 # else
 112 #  if HAVE_STRERROR
 113 #   ifndef HAVE_DECL_STRERROR
 114 "this configure-time declaration test was not run"
 115 #   endif
 116 #   if !HAVE_DECL_STRERROR
 117 char *strerror ();
 118 #   endif
 119 #  else
 120 static char *
 121 private_strerror (int errnum)
 122 {
 123   extern char *sys_errlist[];
 124   extern int sys_nerr;
 125
 126   if (errnum > 0 && errnum <= sys_nerr)
 127     return _(sys_errlist[errnum]);
 128   return _("Unknown system error");
 129 }
 130 #   define strerror private_strerror
 131 #  endif /* HAVE_STRERROR */
 132 # endif /* HAVE_STRERROR_R || defined strerror_r */
 133 #endif  /* not _LIBC */
 134
 135 static void
 136 print_errno_message (int errnum)
 137 {
 138   char const *s;
 139
 140 #if defined HAVE_STRERROR_R || _LIBC
 141   char errbuf[1024];
 142 # if STRERROR_R_CHAR_P || _LIBC
 143   s = __strerror_r (errnum, errbuf, sizeof errbuf);
 144 # else
 145   if (__strerror_r (errnum, errbuf, sizeof errbuf) == 0)
 146     s = errbuf;
 147   else
 148     s = 0;
 149 # endif
 150 #else
 151   s = strerror (errnum);
 152 #endif
 153
 154 #if !_LIBC
 155   if (! s)
 156     s = _("Unknown system error");
 157 #endif
 158
 159 #if _LIBC && USE_IN_LIBIO
 160   if (_IO_fwide (stderr, 0) > 0)
 161     {
 162       __fwprintf (stderr, L": %s", s);
 163       return;
 164     }
 165 #endif
 166
 167   fprintf (stderr, ": %s", s);
 168 }
 169
 170 #ifdef VA_START
 171 static void
 172 error_tail (int status, int errnum, const char *message, va_list args)
 173 {
 174 # if HAVE_VPRINTF || _LIBC
 175 #  if _LIBC && USE_IN_LIBIO
 176   if (_IO_fwide (stderr, 0) > 0)
 177     {
 178 #   define ALLOCA_LIMIT 2000
 179       size_t len = strlen (message) + 1;
 180       wchar_t *wmessage = NULL;
 181       mbstate_t st;
 182       size_t res;
 183       const char *tmp;
 184
 185       do
 186         {
 187           if (len < ALLOCA_LIMIT)
 188             wmessage = (wchar_t *) alloca (len * sizeof (wchar_t));
 189           else
 190             {
 191               if (wmessage != NULL && len / 2 < ALLOCA_LIMIT)
 192                 wmessage = NULL;
 193
 194               wmessage = (wchar_t *) realloc (wmessage,
 195                                               len * sizeof (wchar_t));
 196
 197               if (wmessage == NULL)
 198                 {
 199                   fputws_unlocked (L"out of memory\n", stderr);
 200                   return;
 201                 }
 202             }
 203
 204           memset (&st, '\0', sizeof (st));
 205           tmp =message;
 206         }
 207       while ((res = mbsrtowcs (wmessage, &tmp, len, &st)) == len);
 208
 209       if (res == (size_t) -1)
 210         /* The string cannot be converted.  */
 211         wmessage = (wchar_t *) L"???";
 212
 213       __vfwprintf (stderr, wmessage, args);
 214     }
 215   else
 216 #  endif
 217     vfprintf (stderr, message, args);
 218 # else
 219   _doprnt (message, args, stderr);
 220 # endif
 221   va_end (args);
 222
 223   ++error_message_count;
 224   if (errnum)
 225     print_errno_message (errnum);
 226 # if _LIBC && USE_IN_LIBIO
 227   if (_IO_fwide (stderr, 0) > 0)
 228     putwc (L'\n', stderr);
 229   else
 230 # endif
 231     putc ('\n', stderr);
 232   fflush (stderr);
 233   if (status)
 234     exit (status);
 235 }
 236 #endif
 237
 238
 239 /* Print the program name and error message MESSAGE, which is a printf-style
 240    format string with optional args.
 241    If ERRNUM is nonzero, print its corresponding system error message.
 242    Exit with status STATUS if it is nonzero.  */
 243 /* VARARGS */
 244 void
 245 #if defined VA_START && __STDC__
 246 error (int status, int errnum, const char *message, ...)
 247 #else
 248 error (status, errnum, message, va_alist)
 249      int status;
 250      int errnum;
 251      char *message;
 252      va_dcl
 253 #endif
 254 {
 255 #ifdef VA_START
 256   va_list args;
 257 #endif
 258
 259   fflush (stdout);
 260 #ifdef _LIBC
 261 # ifdef USE_IN_LIBIO
 262   _IO_flockfile (stderr);
 263 # else
 264   __flockfile (stderr);
 265 # endif
 266 #endif
 267   if (error_print_progname)
 268     (*error_print_progname) ();
 269   else
 270     {
 271 #if _LIBC && USE_IN_LIBIO
 272       if (_IO_fwide (stderr, 0) > 0)
 273         __fwprintf (stderr, L"%s: ", program_name);
 274       else
 275 #endif
 276         fprintf (stderr, "%s: ", program_name);
 277     }
 278
 279 #ifdef VA_START
 280   VA_START (args, message);
 281   error_tail (status, errnum, message, args);
 282 #else
 283   fprintf (stderr, message, a1, a2, a3, a4, a5, a6, a7, a8);
 284
 285   ++error_message_count;
 286   if (errnum)
 287     print_errno_message (errnum);
 288   putc ('\n', stderr);
 289   fflush (stderr);
 290   if (status)
 291     exit (status);
 292 #endif
 293
 294 #ifdef _LIBC
 295 # ifdef USE_IN_LIBIO
 296   _IO_funlockfile (stderr);
 297 # else
 298   __funlockfile (stderr);
 299 # endif
 300 #endif
 301 }
 302 \f
 303 /* Sometimes we want to have at most one error per line.  This
 304    variable controls whether this mode is selected or not.  */
 305 int error_one_per_line;
 306
 307 void
 308 #if defined VA_START && __STDC__
 309 error_at_line (int status, int errnum, const char *file_name,
 310                unsigned int line_number, const char *message, ...)
 311 #else
 312 error_at_line (status, errnum, file_name, line_number, message, va_alist)
 313      int status;
 314      int errnum;
 315      const char *file_name;
 316      unsigned int line_number;
 317      char *message;
 318      va_dcl
 319 #endif
 320 {
 321 #ifdef VA_START
 322   va_list args;
 323 #endif
 324
 325   if (error_one_per_line)
 326     {
 327       static const char *old_file_name;
 328       static unsigned int old_line_number;
 329
 330       if (old_line_number == line_number
 331           && (file_name == old_file_name
 332               || strcmp (old_file_name, file_name) == 0))
 333         /* Simply return and print nothing.  */
 334         return;
 335
 336       old_file_name = file_name;
 337       old_line_number = line_number;
 338     }
 339
 340   fflush (stdout);
 341 #ifdef _LIBC
 342 # ifdef USE_IN_LIBIO
 343   _IO_flockfile (stderr);
 344 # else
 345   __flockfile (stderr);
 346 # endif
 347 #endif
 348   if (error_print_progname)
 349     (*error_print_progname) ();
 350   else
 351     {
 352 #if _LIBC && USE_IN_LIBIO
 353       if (_IO_fwide (stderr, 0) > 0)
 354         __fwprintf (stderr, L"%s: ", program_name);
 355       else
 356 #endif
 357         fprintf (stderr, "%s:", program_name);
 358     }
 359
 360   if (file_name != NULL)
 361     {
 362 #if _LIBC && USE_IN_LIBIO
 363       if (_IO_fwide (stderr, 0) > 0)
 364         __fwprintf (stderr, L"%s:%d: ", file_name, line_number);
 365       else
 366 #endif
 367         fprintf (stderr, "%s:%d: ", file_name, line_number);
 368     }
 369
 370 #ifdef VA_START
 371   VA_START (args, message);
 372   error_tail (status, errnum, message, args);
 373 #else
 374   fprintf (stderr, message, a1, a2, a3, a4, a5, a6, a7, a8);
 375
 376   ++error_message_count;
 377   if (errnum)
 378     print_errno_message (errnum);
 379   putc ('\n', stderr);
 380   fflush (stderr);
 381   if (status)
 382     exit (status);
 383 #endif
 384
 385 #ifdef _LIBC
 386 # ifdef USE_IN_LIBIO
 387   _IO_funlockfile (stderr);
 388 # else
 389   __funlockfile (stderr);
 390 # endif
 391 #endif
 392 }
 393
 394 #ifdef _LIBC
 395 /* Make the weak alias.  */
 396 # undef error
 397 # undef error_at_line
 398 weak_alias (__error, error)
 399 weak_alias (__error_at_line, error_at_line)
 400 #endif