lib/error.c

   1 /* error.c -- error handler for noninteractive utilities
   2    Copyright (C) 1990, 91, 92, 93, 94 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
  16    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  17
  18 /* Written by David MacKenzie <djm@gnu.ai.mit.edu>.  */
  19
  20 #ifdef HAVE_CONFIG_H
  21 #include <config.h>
  22 #endif
  23
  24 #include <stdio.h>
  25
  26 #if HAVE_VPRINTF || HAVE_DOPRNT
  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
  40 # include <stdlib.h>
  41 # include <string.h>
  42 #else
  43 void exit ();
  44 #endif
  45
  46 /* If NULL, error will flush stdout, then print on stderr the program
  47    name, a colon and a space.  Otherwise, error will call this
  48    function without parameters instead.  */
  49 void (*error_print_progname) () = NULL;
  50
  51 /* The calling program should define program_name and set it to the
  52    name of the executing program.  */
  53 extern char *program_name;
  54
  55 #if HAVE_STRERROR
  56 char *strerror ();
  57 #else
  58 static char *
  59 private_strerror (errnum)
  60      int errnum;
  61 {
  62   extern char *sys_errlist[];
  63   extern int sys_nerr;
  64
  65   if (errnum > 0 && errnum <= sys_nerr)
  66     return sys_errlist[errnum];
  67   return "Unknown system error";
  68 }
  69 #define strerror private_strerror
  70 #endif
  71
  72 /* Print the program name and error message MESSAGE, which is a printf-style
  73    format string with optional args.
  74    If ERRNUM is nonzero, print its corresponding system error message.
  75    Exit with status STATUS if it is nonzero.  */
  76 /* VARARGS */
  77
  78 void
  79 #if defined(VA_START) && __STDC__
  80 error (int status, int errnum, const char *message, ...)
  81 #else
  82 error (status, errnum, message, va_alist)
  83      int status;
  84      int errnum;
  85      char *message;
  86      va_dcl
  87 #endif
  88 {
  89 #ifdef VA_START
  90   va_list args;
  91 #endif
  92
  93   if (error_print_progname)
  94     (*error_print_progname) ();
  95   else
  96     {
  97       fflush (stdout);
  98       fprintf (stderr, "%s: ", program_name);
  99     }
 100
 101 #ifdef VA_START
 102   VA_START (args, message);
 103 # if HAVE_VPRINTF
 104   vfprintf (stderr, message, args);
 105 # else
 106   _doprnt (message, args, stderr);
 107 # endif
 108   va_end (args);
 109 #else
 110   fprintf (stderr, message, a1, a2, a3, a4, a5, a6, a7, a8);
 111 #endif
 112
 113   if (errnum)
 114     fprintf (stderr, ": %s", strerror (errnum));
 115   putc ('\n', stderr);
 116   fflush (stderr);
 117   if (status)
 118     exit (status);
 119 }