lib/error.c

   1 /* Error handler for noninteractive utilities
   2    Copyright (C) 1990,91,92,93,94,95,96,97,98, 99 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 #else /* not _LIBC */
  80
  81 /* The calling program should define program_name and set it to the
  82    name of the executing program.  */
  83 extern char *program_name;
  84
  85 # ifdef HAVE_STRERROR_R
  86 #  define __strerror_r strerror_r
  87 # else
  88 #  if HAVE_STRERROR
  89 #   ifndef strerror             /* On some systems, strerror is a macro */
  90 char *strerror ();
  91 #   endif
  92 #  else
  93 static char *
  94 private_strerror (errnum)
  95      int errnum;
  96 {
  97   extern char *sys_errlist[];
  98   extern int sys_nerr;
  99
 100   if (errnum > 0 && errnum <= sys_nerr)
 101     return _(sys_errlist[errnum]);
 102   return _("Unknown system error");
 103 }
 104 #   define strerror private_strerror
 105 #  endif /* HAVE_STRERROR */
 106 # endif /* HAVE_STRERROR_R */
 107 #endif  /* not _LIBC */
 108
 109 /* Print the program name and error message MESSAGE, which is a printf-style
 110    format string with optional args.
 111    If ERRNUM is nonzero, print its corresponding system error message.
 112    Exit with status STATUS if it is nonzero.  */
 113 /* VARARGS */
 114
 115 void
 116 #if defined VA_START && __STDC__
 117 error (int status, int errnum, const char *message, ...)
 118 #else
 119 error (status, errnum, message, va_alist)
 120      int status;
 121      int errnum;
 122      char *message;
 123      va_dcl
 124 #endif
 125 {
 126 #ifdef VA_START
 127   va_list args;
 128 #endif
 129
 130   if (error_print_progname)
 131     (*error_print_progname) ();
 132   else
 133     {
 134       fflush (stdout);
 135       fprintf (stderr, "%s: ", program_name);
 136     }
 137
 138 #ifdef VA_START
 139   VA_START (args, message);
 140 # if HAVE_VPRINTF || _LIBC
 141   vfprintf (stderr, message, args);
 142 # else
 143   _doprnt (message, args, stderr);
 144 # endif
 145   va_end (args);
 146 #else
 147   fprintf (stderr, message, a1, a2, a3, a4, a5, a6, a7, a8);
 148 #endif
 149
 150   ++error_message_count;
 151   if (errnum)
 152     {
 153 #if defined HAVE_STRERROR_R || defined _LIBC
 154       char errbuf[1024];
 155       /* Don't use __strerror_r's return value because on some systems
 156          (at least DEC UNIX 4.0[A-D]) strerror_r returns `int'.  */
 157       __strerror_r (errnum, errbuf, sizeof errbuf);
 158       fprintf (stderr, ": %s", errbuf);
 159 #else
 160       fprintf (stderr, ": %s", strerror (errnum));
 161 #endif
 162     }
 163   putc ('\n', stderr);
 164   fflush (stderr);
 165   if (status)
 166     exit (status);
 167 }
 168 \f
 169 /* Sometimes we want to have at most one error per line.  This
 170    variable controls whether this mode is selected or not.  */
 171 int error_one_per_line;
 172
 173 void
 174 #if defined VA_START && __STDC__
 175 error_at_line (int status, int errnum, const char *file_name,
 176                unsigned int line_number, const char *message, ...)
 177 #else
 178 error_at_line (status, errnum, file_name, line_number, message, va_alist)
 179      int status;
 180      int errnum;
 181      const char *file_name;
 182      unsigned int line_number;
 183      char *message;
 184      va_dcl
 185 #endif
 186 {
 187 #ifdef VA_START
 188   va_list args;
 189 #endif
 190
 191   if (error_one_per_line)
 192     {
 193       static const char *old_file_name;
 194       static unsigned int old_line_number;
 195
 196       if (old_line_number == line_number &&
 197           (file_name == old_file_name || !strcmp (old_file_name, file_name)))
 198         /* Simply return and print nothing.  */
 199         return;
 200
 201       old_file_name = file_name;
 202       old_line_number = line_number;
 203     }
 204
 205   if (error_print_progname)
 206     (*error_print_progname) ();
 207   else
 208     {
 209       fflush (stdout);
 210       fprintf (stderr, "%s:", program_name);
 211     }
 212
 213   if (file_name != NULL)
 214     fprintf (stderr, "%s:%d: ", file_name, line_number);
 215
 216 #ifdef VA_START
 217   VA_START (args, message);
 218 # if HAVE_VPRINTF || _LIBC
 219   vfprintf (stderr, message, args);
 220 # else
 221   _doprnt (message, args, stderr);
 222 # endif
 223   va_end (args);
 224 #else
 225   fprintf (stderr, message, a1, a2, a3, a4, a5, a6, a7, a8);
 226 #endif
 227
 228   ++error_message_count;
 229   if (errnum)
 230     {
 231 #if defined HAVE_STRERROR_R || defined _LIBC
 232       char errbuf[1024];
 233       /* Don't use __strerror_r's return value because on some systems
 234          (at least DEC UNIX 4.0[A-D]) strerror_r returns `int'.  */
 235       __strerror_r (errnum, errbuf, sizeof errbuf);
 236       fprintf (stderr, ": %s", errbuf);
 237 #else
 238       fprintf (stderr, ": %s", strerror (errnum));
 239 #endif
 240     }
 241   putc ('\n', stderr);
 242   fflush (stderr);
 243   if (status)
 244     exit (status);
 245 }
 246
 247 #ifdef _LIBC
 248 /* Make the weak alias.  */
 249 # undef error
 250 # undef error_at_line
 251 weak_alias (__error, error)
 252 weak_alias (__error_at_line, error_at_line)
 253 #endif