sysdeps/standalone/open.c

   1 /* Copyright (C) 1994, 1995 Free Software Foundation, Inc.
   2    Ported to standalone by Joel Sherrill jsherril@redstone-emh2.army.mil,
   3      On-Line Applications Research Corporation.
   4
   5 This file is part of the GNU C Library.
   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 #include <ansidecl.h>
  23 #include <errno.h>
  24 #include <fcntl.h>
  25 #include <stdarg.h>
  26 #include <stddef.h>
  27
  28 #include <stdio.h>
  29 #include <stdio_lim.h>
  30 #include <unistd.h>
  31
  32 #define __DECLARE_FILE_DESCRIPTORS__
  33
  34 #include "filedesc.h"
  35
  36 /* Open FILE with access OFLAG.  If OFLAG includes O_CREAT,
  37    a third argument is the file protection.  */
  38 int
  39 DEFUN(__open, (file, oflag), CONST char *file AND int oflag DOTS)
  40 {
  41   int mode;
  42   int newfd;
  43   int index;
  44
  45   if (file == NULL)
  46     {
  47       errno = EINVAL;
  48       return -1;
  49     }
  50
  51   if (oflag & O_CREAT)
  52     {
  53       va_list arg;
  54       va_start(arg, oflag);
  55       mode = va_arg(arg, int);
  56       va_end(arg);
  57     }
  58
  59   /*
  60    *  Find an open slot.
  61    */
  62
  63   newfd = -1;
  64
  65   for ( index=0 ; index< FOPEN_MAX ; index++ )
  66     if ( !__FD_Table[ index ].in_use ) {
  67       newfd = index;
  68       break;
  69     }
  70
  71   if ( newfd == -1 ) {
  72     errno = ENFILE;
  73     return -1;
  74   }
  75
  76   /*
  77    *  Initialize the open slot
  78    */
  79
  80   __FD_Table[ newfd ].in_use = 1;
  81   __FD_Table[ newfd ].flags = oflag;
  82
  83   return newfd;
  84 }
  85
  86 /* Initialization Code for Console I/O */
  87
  88 #ifdef HAVE_GNU_LD
  89 static
  90 #endif
  91 void
  92 DEFUN(__NONE_init_console_io, (argc, argv, envp),
  93       int argc AND char **argv AND char **envp)
  94 {
  95   int index;
  96
  97   for ( index=0 ; index< FOPEN_MAX ; index++ )
  98     __FD_Table[ index ].in_use = 0;
  99
 100   stdin = fopen( "", "r" );
 101
 102   stdout = fopen( "", "w" );
 103
 104   stderr = fopen( "", "w" );
 105
 106   /*
 107    *  Line buffer the standard input and output and use no buffering for
 108    *  standard error.
 109    */
 110
 111   setvbuf( stdin,  NULL, _IOLBF, BUFSIZ );
 112   setvbuf( stdout, NULL, _IOLBF, BUFSIZ );
 113   setvbuf( stderr, NULL, _IONBF, BUFSIZ );
 114
 115   (void) &__NONE_init_console_io;  /* Avoid "defined but not used" warning. */
 116 }
 117
 118 #ifdef  HAVE_GNU_LD
 119 text_set_element (__libc_subinit, __NONE_init_console_io);
 120 #endif
 121
 122 weak_alias (__open, open)