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 #endif  /* not _LIBC */
  96
  97 /* Print the program name and error message MESSAGE, which is a printf-style
  98    format string with optional args.
  99    If ERRNUM is nonzero, print its corresponding system error message.
 100    Exit with status STATUS if it is nonzero.  */
 101 /* VARARGS */
 102
 103 void
 104 #if defined(VA_START) && __STDC__
 105 error (int status, int errnum, const char *message, ...)
 106 #else
 107 error (status, errnum, message, va_alist)
 108      int status;
 109      int errnum;
 110      char *message;
 111      va_dcl
 112 #endif
 113 {
 114 #ifdef VA_START
 115   va_list args;
 116 #endif
 117
 118   if (error_print_progname)
 119     (*error_print_progname) ();
 120   else
 121     {
 122       fflush (stdout);
 123       fprintf (stderr, "%s: ", program_name);
 124     }
 125
 126 #ifdef VA_START
 127   VA_START (args, message);
 128 # if HAVE_VPRINTF || _LIBC
 129   vfprintf (stderr, message, args);
 130 # else
 131   _doprnt (message, args, stderr);
 132 # endif
 133   va_end (args);
 134 #else
 135   fprintf (stderr, message, a1, a2, a3, a4, a5, a6, a7, a8);
 136 #endif
 137
 138   ++error_message_count;
 139   if (errnum)
 140     fprintf (stderr, ": %s", strerror (errnum));
 141   putc ('\n', stderr);
 142   fflush (stderr);
 143   if (status)
 144     exit (status);
 145 }
 146 \f
 147 /* Sometimes we want to have at most one error per line.  This
 148    variable controls whether this mode is selected or not.  */
 149 int error_one_per_line;
 150
 151 void
 152 #if defined(VA_START) && __STDC__
 153 error_at_line (int status, int errnum, const char *file_name,
 154                unsigned int line_number, const char *message, ...)
 155 #else
 156 error_at_line (status, errnum, file_name, line_number, message, va_alist)
 157      int status;
 158      int errnum;
 159      const char *file_name;
 160      unsigned int line_number;
 161      char *message;
 162      va_dcl
 163 #endif
 164 {
 165 #ifdef VA_START
 166   va_list args;
 167 #endif
 168
 169   if (error_one_per_line)
 170     {
 171       static const char *old_file_name;
 172       static unsigned int old_line_number;
 173
 174       if (old_line_number == line_number &&
 175           (file_name == old_file_name || !strcmp (old_file_name, file_name)))
 176         /* Simply return and print nothing.  */
 177         return;
 178
 179       old_file_name = file_name;
 180       old_line_number = line_number;
 181     }
 182
 183   if (error_print_progname)
 184     (*error_print_progname) ();
 185   else
 186     {
 187       fflush (stdout);
 188       fprintf (stderr, "%s:", program_name);
 189     }
 190
 191   if (file_name != NULL)
 192     fprintf (stderr, "%s:%d: ", file_name, line_number);
 193
 194 #ifdef VA_START
 195   VA_START (args, message);
 196 # if HAVE_VPRINTF || _LIBC
 197   vfprintf (stderr, message, args);
 198 # else
 199   _doprnt (message, args, stderr);
 200 # endif
 201   va_end (args);
 202 #else
 203   fprintf (stderr, message, a1, a2, a3, a4, a5, a6, a7, a8);
 204 #endif
 205
 206   ++error_message_count;
 207   if (errnum)
 208     fprintf (stderr, ": %s", strerror (errnum));
 209   putc ('\n', stderr);
 210   fflush (stderr);
 211   if (status)
 212     exit (status);
 213 }