/* FOPEN.C

 * 

 * Portions Copyright (c) 1990-2005 Nokia Corporation and/or its subsidiary(-ies).

 * All rights reserved.

 */

/*

 * Copyright (c) 1990 The Regents of the University of California.

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms are permitted

 * provided that the above copyright notice and this paragraph are

 * duplicated in all such forms and that any documentation,

 * advertising materials, and other materials related to such

 * distribution and use acknowledge that the software was developed

 * by the University of California, Berkeley.  The name of the

 * University may not be used to endorse or promote products derived

 * from this software without specific prior written permission.

 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR

 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED

 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.

 */

/*

FUNCTION

<<fopen>>---open a file

INDEX

	fopen

INDEX

	_fopen_r

ANSI_SYNOPSIS

	#include <stdio.h>

	FILE *fopen(const char *<[file]>, const char *<[mode]>);

	FILE *_fopen_r(void *<[reent]>, 

                       const char *<[file]>, const char *<[mode]>);

TRAD_SYNOPSIS

	#include <stdio.h>

	FILE *fopen(<[file]>, <[mode]>)

	char *<[file]>;

	char *<[mode]>;

	FILE *_fopen_r(<[reent]>, <[file]>, <[mode]>)

	char *<[reent]>;

	char *<[file]>;

	char *<[mode]>;

DESCRIPTION

<<fopen>> initializes the data structures needed to read or write a

file.  Specify the file's name as the string at <[file]>, and the kind

of access you need to the file with the string at <[mode]>.

The alternate function <<_fopen_r>> is a reentrant version.

The extra argument <[reent]> is a pointer to a reentrancy structure.

Three fundamental kinds of access are available: read, write, and append.

<<*<[mode]>>> must begin with one of the three characters `<<r>>',

`<<w>>', or `<<a>>', to select one of these:

o+

o r

Open the file for reading; the operation will fail if the file does

not exist, or if the host system does not permit you to read it.

o w

Open the file for writing @emph{from the beginning} of the file:

effectively, this always creates a new file.  If the file whose name you

specified already existed, its old contents are discarded.

o a

Open the file for appending data, that is writing from the end of

file.  When you open a file this way, all data always goes to the

current end of file; you cannot change this using <<fseek>>.

o-

Some host systems distinguish between ``binary'' and ``text'' files.

Such systems may perform data transformations on data written to, or

read from, files opened as ``text''.

If your system is one of these, then you can append a `<<b>>' to any

of the three modes above, to specify that you are opening the file as

a binary file (the default is to open the file as a text file).

`<<rb>>', then, means ``read binary''; `<<wb>>', ``write binary''; and

`<<ab>>', ``append binary''.

To make C programs more portable, the `<<b>>' is accepted on all

systems, whether or not it makes a difference.

Finally, you might need to both read and write from the same file.

You can also append a `<<+>>' to any of the three modes, to permit

this.  (If you want to append both `<<b>>' and `<<+>>', you can do it

in either order: for example, <<"rb+">> means the same thing as

<<"r+b">> when used as a mode string.)

Use <<"r+">> (or <<"rb+">>) to permit reading and writing anywhere in

an existing file, without discarding any data; <<"w+">> (or <<"wb+">>)

to create a new file (or begin by discarding all data from an old one)

that permits reading and writing anywhere in it; and <<"a+">> (or

<<"ab+">>) to permit reading anywhere in an existing file, but writing

only at the end.

RETURNS

<<fopen>> returns a file pointer which you can use for other file

operations, unless the file you requested could not be opened; in that

situation, the result is <<NULL>>.  If the reason for failure was an

invalid string at <[mode]>, <<errno>> is set to <<EINVAL>>.

PORTABILITY

<<fopen>> is required by ANSI C.

Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,

<<lseek>>, <<open>>, <<read>>, <<sbrk>>, <<write>>.

*/

#include <stdio_r.h>

#include <errno.h>

#include "LOCAL.H"

#include <stdlib_r.h>

#define MaxFullName 255

/**

A reentrant version of fopen().

*/

EXPORT_C FILE * _fopen_r(struct _reent *ptr, const char *file, const char *mode)

	{

	wchar_t _wfile[MaxFullName+1];	

	wchar_t _wmode[MaxFullName+1];

	if ((-1 != mbstowcs(_wfile, file, MaxFullName)) && 

		(-1 != mbstowcs(_wmode, mode, MaxFullName)))

	{

		return _wfopen_r(ptr, _wfile, _wmode);

	}

	ptr->_errno = EILSEQ;

	return NULL;

	}

/**

A reentrant version of wfopen().

*/

EXPORT_C FILE * _wfopen_r(struct _reent *ptr, const wchar_t *file, const wchar_t *mode)

{

  register FILE *fp;

  register int f;

  int flags, oflags;

  if ((flags = __sflags (ptr, mode, &oflags)) == 0)

    return NULL;

  if ((fp = __sfp (ptr)) == NULL)

    return NULL;

  if ((f = _wopen_r (fp->_data, file, oflags, 0666)) < 0)

    {

      fp->_flags = 0;		/* release */

      return NULL;

    }

  fp->_file = (short)f;

  fp->_flags = (short)flags;

  fp->_cookie = (void*) fp;

  fp->_read = __sread;

  fp->_write = __swrite;

  fp->_seek = __sseek;

  fp->_close = __sclose;

  if (fp->_flags & __SAPP)

    fseek (fp, 0, SEEK_END);

  return fp;

}

#ifndef _REENT_ONLY

/**

Open a file.

Opens the file which name is stored in the filename string

and returns a pointer to the file (stream).

Operations allowed to the file returned are defined by the mode parameter.

@return If the file has been succesfully opened 

the function will return a pointer to the file. 

Otherwise a NULL pointer is returned.

@param file name of the file to be opened. 

This paramenter must follow operating system's specifications

and can include a path if the system supports it. 

@param mode type of access requested

*/

EXPORT_C FILE * fopen(const char *file, const char *mode)

{

  return _fopen_r (_REENT, file, mode);

}

EXPORT_C FILE * wfopen(const wchar_t *file, const wchar_t *mode)

{

  return _wfopen_r (_REENT, file, mode);

}

#endif