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1c79356b 1/*
9bccf70c 2 * Copyright (c) 2000-2002 Apple Computer, Inc. All rights reserved.
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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
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61#include <sys/appleapiopts.h>
62
63#ifdef __APPLE_API_UNSTABLE
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64/*
65 * This structure is used for the management of descriptors. It may be
66 * shared by multiple processes.
67 *
68 * A process is initially started out with NDFILE descriptors [XXXstored within
69 * this structureXXX], selected to be enough for typical applications based on
70 * the historical limit of 20 open files (and the usage of descriptors by
71 * shells). If these descriptors are exhausted, a larger descriptor table
72 * may be allocated, up to a process' resource limit; [XXXthe internal arrays
73 * are then unusedXXX]. The initial expansion is set to NDEXTENT; each time
74 * it runs out, it is doubled until the resource limit is reached. NDEXTENT
75 * should be selected to be the biggest multiple of OFILESIZE (see below)
76 * that will fit in a power-of-two sized piece of memory.
77 */
78#define NDFILE 25 /* 125 bytes */
79#define NDEXTENT 50 /* 250 bytes in 256-byte alloc. */
80
81struct filedesc {
82 struct file **fd_ofiles; /* file structures for open files */
83 char *fd_ofileflags; /* per-process open file flags */
84 struct vnode *fd_cdir; /* current directory */
85 struct vnode *fd_rdir; /* root directory */
86 int fd_nfiles; /* number of open files allocated */
87 u_short fd_lastfile; /* high-water mark of fd_ofiles */
88 u_short fd_freefile; /* approx. next free file */
89 u_short fd_cmask; /* mask for file creation */
90 u_short fd_refcnt; /* reference count */
91};
92
93/*
94 * Per-process open flags.
95 */
96#define UF_EXCLOSE 0x01 /* auto-close on exec */
97#define UF_MAPPED 0x02 /* mapped from device */
98#define UF_RESERVED 0x04 /* open pending / in progress */
99
100/*
101 * Storage required per open file descriptor.
102 */
103#define OFILESIZE (sizeof(struct file *) + sizeof(char))
104
105#ifdef KERNEL
106/*
107 * Kernel global variables and routines.
108 */
109extern int dupfdopen __P((struct filedesc *fdp,
110 int indx, int dfd, int mode, int error));
111extern int fdalloc __P((struct proc *p, int want, int *result));
112extern void fdrelse __P((struct proc *p, int fd));
113extern int fdavail __P((struct proc *p, int n));
114extern int fdgetf __P((struct proc *p, int fd, struct file **resultfp));
115#define fdfile(p, fd) \
116 (&(p)->p_fd->fd_ofiles[(fd)])
117#define fdflags(p, fd) \
118 (&(p)->p_fd->fd_ofileflags[(fd)])
119extern int falloc __P((struct proc *p,
120 struct file **resultfp, int *resultfd));
121extern void ffree __P((struct file *fp));
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122
123#ifdef __APPLE_API_PRIVATE
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124extern struct filedesc *fdcopy __P((struct proc *p));
125extern void fdfree __P((struct proc *p));
126extern void fdexec __P((struct proc *p));
9bccf70c 127#endif /* __APPLE_API_PRIVATE */
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128
129#endif /* KERNEL */
130
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131#endif /* __APPLE_API_UNSTABLE */
132
1c79356b 133#endif /* !_SYS_FILEDESC_H_ */