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/*-
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Chris Torek.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)flags.c 8.1 (Berkeley) 6/4/93";
#endif /* LIBC_SCCS and not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/file.h>
#include <stdio.h>
#include <errno.h>
#include "local.h"
/*
* Return the (stdio) flags for a given mode. Store the flags
* to be passed to an _open() syscall through *optr.
* Return 0 on error.
*/
int
__sflags(const char *mode, int *optr)
{
int ret, m, o;
switch (*mode++) {
case 'r': /* open for reading */
ret = __SRD;
m = O_RDONLY;
o = 0;
break;
case 'w': /* open for writing */
ret = __SWR;
m = O_WRONLY;
o = O_CREAT | O_TRUNC;
break;
case 'a': /* open for appending */
ret = __SWR;
m = O_WRONLY;
o = O_CREAT | O_APPEND;
break;
default: /* illegal mode */
errno = EINVAL;
return (0);
}
/* 'b' (binary) is ignored */
if (*mode == 'b')
mode++;
/* [rwa][b]\+ means read and write */
if (*mode == '+') {
mode++;
ret = __SRW;
m = O_RDWR;
}
/* 'b' (binary) can appear here, too -- and is ignored again */
if (*mode == 'b')
mode++;
/* 'x' means exclusive (fail if the file exists) */
if (*mode == 'x') {
mode++;
if (m == O_RDONLY) {
errno = EINVAL;
return (0);
}
o |= O_EXCL;
}
/* set close-on-exec */
if (*mode == 'e')
o |= O_CLOEXEC;
*optr = m | o;
return (ret);
}
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