newlib-cygwin/newlib/libc/stdio64/fdopen64.c

119 lines
2.4 KiB
C

/*
FUNCTION
<<fdopen64>>---turn open large file into a stream
INDEX
fdopen64
INDEX
_fdopen64_r
SYNOPSIS
#include <stdio.h>
FILE *fdopen64(int <[fd]>, const char *<[mode]>);
FILE *_fdopen64_r(void *<[reent]>,
int <[fd]>, const char *<[mode]>);
DESCRIPTION
<<fdopen64>> produces a file descriptor of type <<FILE *>>, from a
descriptor for an already-open file (returned, for example, by the
system subroutine <<open>> rather than by <<fopen>>).
The <[mode]> argument has the same meanings as in <<fopen>>.
RETURNS
File pointer or <<NULL>>, as for <<fopen>>.
*/
#include <sys/types.h>
#include <sys/fcntl.h>
#include <stdio.h>
#include <errno.h>
#include "local.h"
#include <_syslist.h>
#include <sys/lock.h>
extern int __sflags ();
FILE *
_DEFUN (_fdopen64_r, (ptr, fd, mode),
struct _reent *ptr,
int fd,
_CONST char *mode)
{
register FILE *fp;
int flags, oflags;
#ifdef HAVE_FCNTL
int fdflags, fdmode;
#endif
if ((flags = __sflags (ptr, mode, &oflags)) == 0)
return 0;
/* make sure the mode the user wants is a subset of the actual mode */
#ifdef HAVE_FCNTL
if ((fdflags = _fcntl_r (ptr, fd, F_GETFL, 0)) < 0)
return 0;
fdmode = fdflags & O_ACCMODE;
if (fdmode != O_RDWR && (fdmode != (oflags & O_ACCMODE)))
{
ptr->_errno = EBADF;
return 0;
}
#endif
if ((fp = __sfp (ptr)) == 0)
return 0;
_newlib_flockfile_start(fp);
fp->_flags = flags;
/* POSIX recommends setting the O_APPEND bit on fd to match append
streams. Someone may later clear O_APPEND on fileno(fp), but the
stream must still remain in append mode. Rely on __sflags
setting __SAPP properly. */
#ifdef HAVE_FCNTL
if ((oflags & O_APPEND) && !(fdflags & O_APPEND))
_fcntl_r (ptr, fd, F_SETFL, fdflags | O_APPEND);
#endif
fp->_file = fd;
fp->_cookie = (_PTR) fp;
#undef _read
#undef _write
#undef _seek
#undef _close
fp->_read = __sread;
fp->_write = __swrite64;
fp->_seek = __sseek;
fp->_seek64 = __sseek64;
fp->_close = __sclose;
#ifdef __SCLE
/* Explicit given mode results in explicit setting mode on fd */
if (oflags & O_BINARY)
setmode(fp->_file, O_BINARY);
else if (oflags & O_TEXT)
setmode(fp->_file, O_TEXT);
if (__stextmode(fp->_file))
fp->_flags |= __SCLE;
#endif
fp->_flags |= __SL64;
_newlib_flockfile_end(fp);
return fp;
}
#ifndef _REENT_ONLY
FILE *
_DEFUN (fdopen64, (fd, mode),
int fd,
_CONST char *mode)
{
return _fdopen64_r (_REENT, fd, mode);
}
#endif