git.saurik.com Git - apple/libc.git/blame_incremental

... / ...

Commit	Line	Data
	1	/*-
	2	* Copyright (c) 1990, 1993
	3	* The Regents of the University of California. All rights reserved.
	4	*
	5	* This code is derived from software contributed to Berkeley by
	6	* Chris Torek.
	7	*
	8	* Redistribution and use in source and binary forms, with or without
	9	* modification, are permitted provided that the following conditions
	10	* are met:
	11	* 1. Redistributions of source code must retain the above copyright
	12	* notice, this list of conditions and the following disclaimer.
	13	* 2. Redistributions in binary form must reproduce the above copyright
	14	* notice, this list of conditions and the following disclaimer in the
	15	* documentation and/or other materials provided with the distribution.
	16	* 4. Neither the name of the University nor the names of its contributors
	17	* may be used to endorse or promote products derived from this software
	18	* without specific prior written permission.
	19	*
	20	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	21	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	22	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	23	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	24	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	25	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	26	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	27	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	28	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	29	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	30	* SUCH DAMAGE.
	31	*/
	32
	33	#ifdef VARIANT_DARWINEXTSN
	34	#define _DARWIN_UNLIMITED_STREAMS
	35	#define COUNT 0
	36	#elif defined(VARIANT_LEGACY)
	37	#define COUNT 0
	38	#else
	39	#define COUNT 1
	40	#endif
	41
	42	#if defined(LIBC_SCCS) && !defined(lint)
	43	static char sccsid[] = "@(#)fopen.c 8.1 (Berkeley) 6/4/93";
	44	#endif /* LIBC_SCCS and not lint */
	45	#include <sys/cdefs.h>
	46	__FBSDID("$FreeBSD: src/lib/libc/stdio/fopen.c,v 1.14 2008/04/22 17:03:32 jhb Exp $");
	47
	48	#include "namespace.h"
	49	#include <sys/types.h>
	50	#include <sys/stat.h>
	51	#include <fcntl.h>
	52	#include <unistd.h>
	53	#include <stdio.h>
	54	#include <errno.h>
	55	#include <limits.h>
	56	#include "un-namespace.h"
	57
	58	#include "local.h"
	59
	60	FILE *
	61	fopen(file, mode)
	62	const char * __restrict file;
	63	const char * __restrict mode;
	64	{
	65	FILE *fp;
	66	int f;
	67	int flags, oflags;
	68
	69	if ((flags = __sflags(mode, &oflags)) == 0)
	70	return (NULL);
	71	if ((fp = __sfp(COUNT)) == NULL)
	72	return (NULL);
	73	if ((f = _open(file, oflags, DEFFILEMODE)) < 0) {
	74	__sfprelease(fp); /* release */
	75	return (NULL);
	76	}
	77	/*
	78	* File descriptors are a full int, but _file is only a short.
	79	* If we get a valid file descriptor that is greater than
	80	* SHRT_MAX, then the fd will get sign-extended into an
	81	* invalid file descriptor. Handle this case by failing the
	82	* open.
	83	*/
	84	if (f > SHRT_MAX) {
	85	fp->_flags = 0; /* release */
	86	_close(f);
	87	errno = EMFILE;
	88	return (NULL);
	89	}
	90	fp->_file = f;
	91	fp->_flags = flags;
	92	fp->_cookie = fp;
	93	fp->_read = __sread;
	94	fp->_write = __swrite;
	95	fp->_seek = __sseek;
	96	fp->_close = __sclose;
	97	/*
	98	* When opening in append mode, even though we use O_APPEND,
	99	* we need to seek to the end so that ftell() gets the right
	100	* answer. If the user then alters the seek pointer, or
	101	* the file extends, this will fail, but there is not much
	102	* we can do about this. (We could set __SAPP and check in
	103	* fseek and ftell.)
	104	*/
	105	if (oflags & O_APPEND)
	106	(void)_sseek(fp, (fpos_t)0, SEEK_END);
	107	return (fp);
	108	}