lib/error.c

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