misc/error.c

   1 /* Error handler for noninteractive utilities
   2    Copyright (C) 1990,91,92,93,94,95,96,97,98 Free Software Foundation, Inc.
   3
   4    This file is part of the GNU C Library.  Its master source is NOT part of
   5    the C library, however.  The master source lives in /gd/gnu/lib.
   6
   7    The GNU C Library is free software; you can redistribute it and/or
   8    modify it under the terms of the GNU Library General Public License as
   9    published by the Free Software Foundation; either version 2 of the
  10    License, or (at your option) any later version.
  11
  12    The GNU C Library is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15    Library General Public License for more details.
  16
  17    You should have received a copy of the GNU Library General Public
  18    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  19    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 /* Written by David MacKenzie <djm@gnu.ai.mit.edu>.  */
  23
  24 #ifdef HAVE_CONFIG_H
  25 # include <config.h>
  26 #endif
  27
  28 #include <stdio.h>
  29
  30 #if HAVE_VPRINTF || HAVE_DOPRNT || _LIBC
  31 # if __STDC__
  32 #  include <stdarg.h>
  33 #  define VA_START(args, lastarg) va_start(args, lastarg)
  34 # else
  35 #  include <varargs.h>
  36 #  define VA_START(args, lastarg) va_start(args)
  37 # endif
  38 #else
  39 # define va_alist a1, a2, a3, a4, a5, a6, a7, a8
  40 # define va_dcl char *a1, *a2, *a3, *a4, *a5, *a6, *a7, *a8;
  41 #endif
  42
  43 #if STDC_HEADERS || _LIBC
  44 # include <stdlib.h>
  45 # include <string.h>
  46 #else
  47 void exit ();
  48 #endif
  49
  50 #include "error.h"
  51
  52 #ifndef _
  53 # define _(String) String
  54 #endif
  55
  56 /* If NULL, error will flush stdout, then print on stderr the program
  57    name, a colon and a space.  Otherwise, error will call this
  58    function without parameters instead.  */
  59 void (*error_print_progname) (
  60 #if __STDC__ - 0
  61                               void
  62 #endif
  63                               );
  64
  65 /* This variable is incremented each time `error' is called.  */
  66 unsigned int error_message_count;
  67
  68 #ifdef _LIBC
  69 /* In the GNU C library, there is a predefined variable for this.  */
  70
  71 # define program_name program_invocation_name
  72 # include <errno.h>
  73
  74 /* In GNU libc we want do not want to use the common name `error' directly.
  75    Instead make it a weak alias.  */
  76 # define error __error
  77 # define error_at_line __error_at_line
  78
  79 # ifdef USE_IN_LIBIO
  80 # include <libio/iolibio.h>
  81 #  define fflush(s) _IO_fflush (s)
  82 # endif
  83
  84 #else /* not _LIBC */
  85
  86 /* The calling program should define program_name and set it to the
  87    name of the executing program.  */
  88 extern char *program_name;
  89
  90 # ifdef HAVE_STRERROR_R
  91 #  define __strerror_r strerror_r
  92 # else
  93 #  if HAVE_STRERROR
  94 #   ifndef strerror             /* On some systems, strerror is a macro */
  95 char *strerror ();
  96 #   endif
  97 #  else
  98 static char *
  99 private_strerror (errnum)
 100      int errnum;
 101 {
 102   extern char *sys_errlist[];
 103   extern int sys_nerr;
 104
 105   if (errnum > 0 && errnum <= sys_nerr)
 106     return _(sys_errlist[errnum]);
 107   return _("Unknown system error");
 108 }
 109 #   define strerror private_strerror
 110 #  endif /* HAVE_STRERROR */
 111 # endif /* HAVE_STRERROR_R */
 112 #endif  /* not _LIBC */
 113
 114 /* Print the program name and error message MESSAGE, which is a printf-style
 115    format string with optional args.
 116    If ERRNUM is nonzero, print its corresponding system error message.
 117    Exit with status STATUS if it is nonzero.  */
 118 /* VARARGS */
 119
 120 void
 121 #if defined VA_START && __STDC__
 122 error (int status, int errnum, const char *message, ...)
 123 #else
 124 error (status, errnum, message, va_alist)
 125      int status;
 126      int errnum;
 127      char *message;
 128      va_dcl
 129 #endif
 130 {
 131 #ifdef VA_START
 132   va_list args;
 133 #endif
 134
 135   if (error_print_progname)
 136     (*error_print_progname) ();
 137   else
 138     {
 139       fflush (stdout);
 140       fprintf (stderr, "%s: ", program_name);
 141     }
 142
 143 #ifdef VA_START
 144   VA_START (args, message);
 145 # if HAVE_VPRINTF || _LIBC
 146   vfprintf (stderr, message, args);
 147 # else
 148   _doprnt (message, args, stderr);
 149 # endif
 150   va_end (args);
 151 #else
 152   fprintf (stderr, message, a1, a2, a3, a4, a5, a6, a7, a8);
 153 #endif
 154
 155   ++error_message_count;
 156   if (errnum)
 157     {
 158 #if defined HAVE_STRERROR_R || defined _LIBC
 159       char errbuf[1024];
 160       /* Don't use __strerror_r's return value because on some systems
 161          (at least DEC UNIX 4.0[A-D]) strerror_r returns `int'.  */
 162       __strerror_r (errnum, errbuf, sizeof errbuf);
 163       fprintf (stderr, ": %s", errbuf);
 164 #else
 165       fprintf (stderr, ": %s", strerror (errnum));
 166 #endif
 167     }
 168   putc ('\n', stderr);
 169   fflush (stderr);
 170   if (status)
 171     exit (status);
 172 }
 173 \f
 174 /* Sometimes we want to have at most one error per line.  This
 175    variable controls whether this mode is selected or not.  */
 176 int error_one_per_line;
 177
 178 void
 179 #if defined VA_START && __STDC__
 180 error_at_line (int status, int errnum, const char *file_name,
 181                unsigned int line_number, const char *message, ...)
 182 #else
 183 error_at_line (status, errnum, file_name, line_number, message, va_alist)
 184      int status;
 185      int errnum;
 186      const char *file_name;
 187      unsigned int line_number;
 188      char *message;
 189      va_dcl
 190 #endif
 191 {
 192 #ifdef VA_START
 193   va_list args;
 194 #endif
 195
 196   if (error_one_per_line)
 197     {
 198       static const char *old_file_name;
 199       static unsigned int old_line_number;
 200
 201       if (old_line_number == line_number &&
 202           (file_name == old_file_name || !strcmp (old_file_name, file_name)))
 203         /* Simply return and print nothing.  */
 204         return;
 205
 206       old_file_name = file_name;
 207       old_line_number = line_number;
 208     }
 209
 210   if (error_print_progname)
 211     (*error_print_progname) ();
 212   else
 213     {
 214       fflush (stdout);
 215       fprintf (stderr, "%s:", program_name);
 216     }
 217
 218   if (file_name != NULL)
 219     fprintf (stderr, "%s:%d: ", file_name, line_number);
 220
 221 #ifdef VA_START
 222   VA_START (args, message);
 223 # if HAVE_VPRINTF || _LIBC
 224   vfprintf (stderr, message, args);
 225 # else
 226   _doprnt (message, args, stderr);
 227 # endif
 228   va_end (args);
 229 #else
 230   fprintf (stderr, message, a1, a2, a3, a4, a5, a6, a7, a8);
 231 #endif
 232
 233   ++error_message_count;
 234   if (errnum)
 235     {
 236 #if defined HAVE_STRERROR_R || defined _LIBC
 237       char errbuf[1024];
 238       fprintf (stderr, ": %s", __strerror_r (errnum, errbuf, sizeof errbuf));
 239 #else
 240       fprintf (stderr, ": %s", strerror (errnum));
 241 #endif
 242     }
 243   putc ('\n', stderr);
 244   fflush (stderr);
 245   if (status)
 246     exit (status);
 247 }
 248
 249 #ifdef _LIBC
 250 /* Make the weak alias.  */
 251 # undef error
 252 # undef error_at_line
 253 weak_alias (__error, error)
 254 weak_alias (__error_at_line, error_at_line)
 255 #endif