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

... / ...

Commit	Line	Data
	1	/*
	2	* Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
	6	* The contents of this file constitute Original Code as defined in and
	7	* are subject to the Apple Public Source License Version 1.1 (the
	8	* "License"). You may not use this file except in compliance with the
	9	* License. Please obtain a copy of the License at
	10	* http://www.apple.com/publicsource and read it before using this file.
	11	*
	12	* This Original Code and all software distributed under the License are
	13	* distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	14	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	15	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	16	* FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
	17	* License for the specific language governing rights and limitations
	18	* under the License.
	19	*
	20	* @APPLE_LICENSE_HEADER_END@
	21	*/
	22	/* Copyright (c) 1995, 1997 Apple Computer, Inc. All Rights Reserved */
	23	/*
	24	* Copyright (c) 1990, 1993
	25	* The Regents of the University of California. All rights reserved.
	26	*
	27	* Redistribution and use in source and binary forms, with or without
	28	* modification, are permitted provided that the following conditions
	29	* are met:
	30	* 1. Redistributions of source code must retain the above copyright
	31	* notice, this list of conditions and the following disclaimer.
	32	* 2. Redistributions in binary form must reproduce the above copyright
	33	* notice, this list of conditions and the following disclaimer in the
	34	* documentation and/or other materials provided with the distribution.
	35	* 3. All advertising materials mentioning features or use of this software
	36	* must display the following acknowledgement:
	37	* This product includes software developed by the University of
	38	* California, Berkeley and its contributors.
	39	* 4. Neither the name of the University nor the names of its contributors
	40	* may be used to endorse or promote products derived from this software
	41	* without specific prior written permission.
	42	*
	43	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	44	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	45	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	46	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	47	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	48	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	49	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	50	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	51	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	52	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	53	* SUCH DAMAGE.
	54	*
	55	* @(#)filedesc.h 8.1 (Berkeley) 6/2/93
	56	*/
	57
	58	#ifndef _SYS_FILEDESC_H_
	59	#define _SYS_FILEDESC_H_
	60
	61	/*
	62	* This structure is used for the management of descriptors. It may be
	63	* shared by multiple processes.
	64	*
	65	* A process is initially started out with NDFILE descriptors [XXXstored within
	66	* this structureXXX], selected to be enough for typical applications based on
	67	* the historical limit of 20 open files (and the usage of descriptors by
	68	* shells). If these descriptors are exhausted, a larger descriptor table
	69	* may be allocated, up to a process' resource limit; [XXXthe internal arrays
	70	* are then unusedXXX]. The initial expansion is set to NDEXTENT; each time
	71	* it runs out, it is doubled until the resource limit is reached. NDEXTENT
	72	* should be selected to be the biggest multiple of OFILESIZE (see below)
	73	* that will fit in a power-of-two sized piece of memory.
	74	*/
	75	#define NDFILE 25 /* 125 bytes */
	76	#define NDEXTENT 50 /* 250 bytes in 256-byte alloc. */
	77
	78	struct filedesc {
	79	struct file *fd_ofiles; / file structures for open files */
	80	char fd_ofileflags; / per-process open file flags */
	81	struct vnode fd_cdir; / current directory */
	82	struct vnode fd_rdir; / root directory */
	83	int fd_nfiles; /* number of open files allocated */
	84	u_short fd_lastfile; /* high-water mark of fd_ofiles */
	85	u_short fd_freefile; /* approx. next free file */
	86	u_short fd_cmask; /* mask for file creation */
	87	u_short fd_refcnt; /* reference count */
	88	};
	89
	90	/*
	91	* Per-process open flags.
	92	*/
	93	#define UF_EXCLOSE 0x01 /* auto-close on exec */
	94	#define UF_MAPPED 0x02 /* mapped from device */
	95	#define UF_RESERVED 0x04 /* open pending / in progress */
	96
	97	/*
	98	* Storage required per open file descriptor.
	99	*/
	100	#define OFILESIZE (sizeof(struct file *) + sizeof(char))
	101
	102	#ifdef KERNEL
	103	/*
	104	* Kernel global variables and routines.
	105	*/
	106	extern int dupfdopen __P((struct filedesc *fdp,
	107	int indx, int dfd, int mode, int error));
	108	extern int fdalloc __P((struct proc p, int want, int result));
	109	extern void fdrelse __P((struct proc *p, int fd));
	110	extern int fdavail __P((struct proc *p, int n));
	111	extern int fdgetf __P((struct proc p, int fd, struct file *resultfp));
	112	#define fdfile(p, fd) \
	113	(&(p)->p_fd->fd_ofiles[(fd)])
	114	#define fdflags(p, fd) \
	115	(&(p)->p_fd->fd_ofileflags[(fd)])
	116	extern int falloc __P((struct proc *p,
	117	struct file *resultfp, int resultfd));
	118	extern void ffree __P((struct file *fp));
	119	extern struct filedesc fdcopy __P((struct proc p));
	120	extern void fdfree __P((struct proc *p));
	121	extern void fdexec __P((struct proc *p));
	122
	123	#endif /* KERNEL */
	124
	125	#endif /* !_SYS_FILEDESC_H_ */