glibc/sysdeps/posix/fdopen.c

73 lines
1.8 KiB
C

/* Copyright (C) 1991, 1992, 1993 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA. */
#include <ansidecl.h>
#include <errno.h>
#include <stdio.h>
#include <fcntl.h>
/* Defined in fopen.c. */
extern int EXFUN(__getmode, (CONST char *mode, __io_mode *mptr));
/* Open a new stream on a given system file descriptor. */
FILE *
DEFUN(fdopen, (fd, mode), int fd AND CONST char *mode)
{
register FILE *stream;
__io_mode m;
int dflags;
if (!__getmode (mode, &m))
return NULL;
/* Verify the FD is valid and allows the access MODE specifies. */
dflags = __fcntl (fd, F_GETFL);
if (dflags == -1)
/* FD was invalid; fcntl has already set errno. */
return NULL;
/* Check the access mode. */
switch (dflags & O_ACCMODE)
{
case O_RDONLY:
if (!m.__read)
{
errno = EBADF;
return NULL;
}
break;
case O_WRONLY:
if (!m.__write)
{
errno = EBADF;
return NULL;
}
break;
}
stream = __newstream ();
if (stream == NULL)
return NULL;
stream->__cookie = (PTR) fd;
stream->__mode = m;
return stream;
}