misc/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 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
  19 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  20 Cambridge, MA 02139, 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 /* If NULL, error will flush stdout, then print on stderr the program
  51    name, a colon and a space.  Otherwise, error will call this
  52    function without parameters instead.  */
  53 void (*error_print_progname) (
  54 #if __STDC__
  55                               void
  56 #endif
  57                               );
  58
  59 /* This variable is incremented each time `error' is called.  */
  60 unsigned int error_message_count;
  61
  62 #ifdef _LIBC
  63 /* In the GNU C library, there is a predefined variable for this.  */
  64
  65 #define program_name program_invocation_name
  66 #include <errno.h>
  67
  68 #else
  69
  70 /* The calling program should define program_name and set it to the
  71    name of the executing program.  */
  72 extern char *program_name;
  73
  74 #if HAVE_STRERROR
  75 # ifndef strerror               /* On some systems, strerror is a macro */
  76 char *strerror ();
  77 # endif
  78 #else
  79 static char *
  80 private_strerror (errnum)
  81      int errnum;
  82 {
  83   extern char *sys_errlist[];
  84   extern int sys_nerr;
  85
  86   if (errnum > 0 && errnum <= sys_nerr)
  87     return sys_errlist[errnum];
  88   return "Unknown system error";
  89 }
  90 #define strerror private_strerror
  91 #endif  /* HAVE_STRERROR */
  92 #endif  /* _LIBC */
  93
  94 /* Print the program name and error message MESSAGE, which is a printf-style
  95    format string with optional args.
  96    If ERRNUM is nonzero, print its corresponding system error message.
  97    Exit with status STATUS if it is nonzero.  */
  98 /* VARARGS */
  99
 100 void
 101 #if defined(VA_START) && __STDC__
 102 error (int status, int errnum, const char *message, ...)
 103 #else
 104 error (status, errnum, message, va_alist)
 105      int status;
 106      int errnum;
 107      char *message;
 108      va_dcl
 109 #endif
 110 {
 111 #ifdef VA_START
 112   va_list args;
 113 #endif
 114
 115   if (error_print_progname)
 116     (*error_print_progname) ();
 117   else
 118     {
 119       fflush (stdout);
 120       fprintf (stderr, "%s: ", program_name);
 121     }
 122
 123 #ifdef VA_START
 124   VA_START (args, message);
 125 # if HAVE_VPRINTF || _LIBC
 126   vfprintf (stderr, message, args);
 127 # else
 128   _doprnt (message, args, stderr);
 129 # endif
 130   va_end (args);
 131 #else
 132   fprintf (stderr, message, a1, a2, a3, a4, a5, a6, a7, a8);
 133 #endif
 134
 135   ++error_message_count;
 136
 137   if (errnum)
 138     fprintf (stderr, ": %s", strerror (errnum));
 139   putc ('\n', stderr);
 140   fflush (stderr);
 141   if (status)
 142     exit (status);
 143 }