contrib/cpio/error.c

   1 /* error.c -- error handler for noninteractive utilities
   2    Copyright (C) 1990, 91, 92, 93, 94, 95 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 || _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 /* This variable is incremented each time `error' is called.  */
  47 unsigned int error_message_count;
  48
  49 /* If NULL, error will flush stdout, then print on stderr the program
  50    name, a colon and a space.  Otherwise, error will call this
  51    function without parameters instead.  */
  52 void (*error_print_progname) () = NULL;
  53
  54 #ifdef _LIBC
  55 #define program_name program_invocation_name
  56 #endif
  57
  58 /* The calling program should define program_name and set it to the
  59    name of the executing program.  */
  60 extern char *program_name;
  61
  62 #if HAVE_STRERROR || _LIBC
  63 # ifndef strerror               /* On some systems, strerror is a macro */
  64 char *strerror ();
  65 # endif
  66 #else
  67 static char *
  68 private_strerror (errnum)
  69      int errnum;
  70 {
  71   extern char *sys_errlist[];
  72   extern int sys_nerr;
  73
  74   if (errnum > 0 && errnum <= sys_nerr)
  75     return sys_errlist[errnum];
  76   return "Unknown system error";
  77 }
  78 #define strerror private_strerror
  79 #endif
  80
  81 /* Print the program name and error message MESSAGE, which is a printf-style
  82    format string with optional args.
  83    If ERRNUM is nonzero, print its corresponding system error message.
  84    Exit with status STATUS if it is nonzero.  */
  85 /* VARARGS */
  86
  87 void
  88 #if defined(VA_START) && __STDC__
  89 error (int status, int errnum, const char *message, ...)
  90 #else
  91 error (status, errnum, message, va_alist)
  92      int status;
  93      int errnum;
  94      char *message;
  95      va_dcl
  96 #endif
  97 {
  98 #ifdef VA_START
  99   va_list args;
 100 #endif
 101
 102   if (error_print_progname)
 103     (*error_print_progname) ();
 104   else
 105     {
 106       fflush (stdout);
 107       fprintf (stderr, "%s: ", program_name);
 108     }
 109
 110 #ifdef VA_START
 111   VA_START (args, message);
 112 # if HAVE_VPRINTF || _LIBC
 113   vfprintf (stderr, message, args);
 114 # else
 115   _doprnt (message, args, stderr);
 116 # endif
 117   va_end (args);
 118 #else
 119   fprintf (stderr, message, a1, a2, a3, a4, a5, a6, a7, a8);
 120 #endif
 121
 122   ++error_message_count;
 123
 124   if (errnum)
 125     fprintf (stderr, ": %s", strerror (errnum));
 126   putc ('\n', stderr);
 127   fflush (stderr);
 128   if (status)
 129     exit (status);
 130 }