windows-nt/Source/XPSP1/NT/base/crts/crtw32/stdio/fopen.c
2020-09-26 16:20:57 +08:00

154 lines
4 KiB
C

/***
*fopen.c - open a file
*
* Copyright (c) 1985-2001, Microsoft Corporation. All rights reserved.
*
*Purpose:
* defines fopen() and _fsopen() - open a file as a stream and open a file
* with a specified sharing mode as a stream
*
*Revision History:
* 09-02-83 RN initial version
* 04-13-87 JCR added const to declarations
* 11-01-87 JCR Multi-thread support
* 12-11-87 JCR Added "_LOAD_DS" to declaration
* 05-31-88 PHG Merged DLL and normal versions
* 11-14-88 GJF Added _fsopen().
* 02-15-90 GJF Fixed copyright and indents
* 03-19-90 GJF Replaced _LOAD_DS with _CALLTYPE1, added #include
* <cruntime.h> and removed #include <register.h>.
* 07-23-90 SBM Replaced <assertm.h> by <assert.h>
* 10-02-90 GJF New-style function declarators.
* 01-21-91 GJF ANSI naming.
* 03-26-92 DJM POSIX support
* 04-06-93 SKS Replace _CRTAPI* with __cdecl
* 11-01-93 CFW Enable Unicode variant.
* 02-06-94 CFW assert -> _ASSERTE.
* 02-20-95 GJF Replaced WPRFLAG with _UNICODE.
* 03-07-95 GJF _[un]lock_str macros now take FILE * arg.
* 02-27-98 GJF Exception-safe locking.
* 10-06-99 PML Set errno EMFILE when out of streams.
*
*******************************************************************************/
#include <cruntime.h>
#include <stdio.h>
#include <share.h>
#include <dbgint.h>
#include <internal.h>
#include <mtdll.h>
#include <file2.h>
#include <tchar.h>
#include <errno.h>
/***
*FILE *_fsopen(file, mode, shflag) - open a file
*
*Purpose:
* Opens the file specified as a stream. mode determines file mode:
* "r": read "w": write "a": append
* "r+": read/write "w+": open empty for read/write
* "a+": read/append
* Append "t" or "b" for text and binary mode. shflag determines the
* sharing mode. Values are the same as for sopen().
*
*Entry:
* char *file - file name to open
* char *mode - mode of file access
*
*Exit:
* returns pointer to stream
* returns NULL if fails
*
*Exceptions:
*
*******************************************************************************/
FILE * __cdecl _tfsopen (
const _TSCHAR *file,
const _TSCHAR *mode
#ifndef _POSIX_
,int shflag
#endif
)
{
REG1 FILE *stream;
REG2 FILE *retval;
_ASSERTE(file != NULL);
_ASSERTE(*file != _T('\0'));
_ASSERTE(mode != NULL);
_ASSERTE(*mode != _T('\0'));
/* Get a free stream */
/* [NOTE: _getstream() returns a locked stream.] */
if ((stream = _getstream()) == NULL) {
errno = EMFILE;
return(NULL);
}
#ifdef _MT
__try {
#endif
/* open the stream */
#ifdef _POSIX_
#ifdef _UNICODE
retval = _wopenfile(file,mode, stream);
#else
retval = _openfile(file,mode, stream);
#endif
#else
#ifdef _UNICODE
retval = _wopenfile(file,mode,shflag,stream);
#else
retval = _openfile(file,mode,shflag,stream);
#endif
#endif
#ifdef _MT
}
__finally {
_unlock_str(stream);
}
#endif
return(retval);
}
/***
*FILE *fopen(file, mode) - open a file
*
*Purpose:
* Opens the file specified as a stream. mode determines file mode:
* "r": read "w": write "a": append
* "r+": read/write "w+": open empty for read/write
* "a+": read/append
* Append "t" or "b" for text and binary mode
*
*Entry:
* char *file - file name to open
* char *mode - mode of file access
*
*Exit:
* returns pointer to stream
* returns NULL if fails
*
*Exceptions:
*
*******************************************************************************/
FILE * __cdecl _tfopen (
const _TSCHAR *file,
const _TSCHAR *mode
)
{
#ifdef _POSIX_
return( _tfsopen(file, mode) );
#else
return( _tfsopen(file, mode, _SH_DENYNO) );
#endif
}