bsd/sys/file.h

   1 /*
   2  * Copyright (c) 2000-2002 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) 1982, 1986, 1989, 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  *      @(#)file.h      8.3 (Berkeley) 1/9/95
  56  */
  57
  58 #ifndef _SYS_FILE_H_
  59 #define _SYS_FILE_H_
  60
  61 #include <sys/appleapiopts.h>
  62 #include <sys/fcntl.h>
  63 #include <sys/unistd.h>
  64
  65 #ifdef KERNEL
  66 #include <sys/errno.h>
  67 #include <sys/queue.h>
  68 #include <sys/cdefs.h>
  69
  70 struct proc;
  71 struct uio;
  72 struct knote;
  73 #ifdef __APPLE_API_UNSTABLE
  74
  75 /*
  76  * Kernel descriptor table.
  77  * One entry for each open kernel vnode and socket.
  78  */
  79 struct file {
  80         LIST_ENTRY(file) f_list;/* list of active files */
  81         short   f_flag;         /* see fcntl.h */
  82 #define DTYPE_VNODE     1       /* file */
  83 #define DTYPE_SOCKET    2       /* communications endpoint */
  84 #define DTYPE_PSXSHM    3       /* POSIX Shared memory */
  85 #define DTYPE_PSXSEM    4       /* POSIX Semaphores */
  86 #define DTYPE_KQUEUE    5       /* kqueue */
  87         short   f_type;         /* descriptor type */
  88         short   f_count;        /* reference count */
  89         short   f_msgcount;     /* references from message queue */
  90         struct  ucred *f_cred;  /* credentials associated with descriptor */
  91         struct  fileops {
  92                 int     (*fo_read)      __P((struct file *fp, struct uio *uio,
  93                                             struct ucred *cred, int flags,
  94                                             struct proc *p));
  95                 int     (*fo_write)     __P((struct file *fp, struct uio *uio,
  96                                             struct ucred *cred, int flags,
  97                                             struct proc *p));
  98 #define FOF_OFFSET      1
  99                 int     (*fo_ioctl)     __P((struct file *fp, u_long com,
 100                                             caddr_t data, struct proc *p));
 101                 int     (*fo_select)    __P((struct file *fp, int which,
 102                                                 void *wql, struct proc *p));
 103                 int     (*fo_close)     __P((struct file *fp, struct proc *p));
 104                 int     (*fo_kqfilter)  __P((struct file *fp, struct knote *kn,
 105                                              struct proc *p));
 106         } *f_ops;
 107         off_t   f_offset;
 108         caddr_t f_data;         /* vnode or socket or SHM or semaphore */
 109 };
 110
 111 #ifdef __APPLE_API_PRIVATE
 112 LIST_HEAD(filelist, file);
 113 extern struct filelist filehead;        /* head of list of open files */
 114 extern int maxfiles;                    /* kernel limit on number of open files */
 115 extern int nfiles;                      /* actual number of open files */
 116 #endif /* __APPLE_API_PRIVATE */
 117
 118 __BEGIN_DECLS
 119 int fref __P((struct file *));  /* take a reference on file pointer */
 120 int frele __P((struct file *)); /* release a reference on file pointer */
 121 int fcount __P((struct file *));        /* returns the reference count */
 122
 123 static __inline int fo_read __P((struct file *fp, struct uio *uio,
 124         struct ucred *cred, int flags, struct proc *p));
 125 static __inline int fo_write __P((struct file *fp, struct uio *uio,
 126         struct ucred *cred, int flags, struct proc *p));
 127 static __inline int fo_ioctl __P((struct file *fp, u_long com, caddr_t data,
 128         struct proc *p));
 129 static __inline int fo_select __P((struct file *fp, int which, void *wql,
 130         struct proc *p));
 131 static __inline int fo_close __P((struct file *fp, struct proc *p));
 132 static __inline int fo_kqfilter __P((struct file *fp, struct knote *kn,
 133         struct proc *p));
 134
 135 static __inline int
 136 fo_read(struct file *fp, struct uio *uio, struct ucred *cred, int flags, struct proc *p)
 137 {
 138         int error;
 139
 140         if ((error = fref(fp)) == -1)
 141                 return (EBADF);
 142         error = (*fp->f_ops->fo_read)(fp, uio, cred, flags, p);
 143         frele(fp);
 144         return (error);
 145 }
 146
 147 static __inline int
 148 fo_write(struct file *fp, struct uio *uio, struct ucred *cred, int flags, struct proc *p)
 149 {
 150         int error;
 151
 152         if ((error = fref(fp)) == -1)
 153                 return (EBADF);
 154         error = (*fp->f_ops->fo_write)(fp, uio, cred, flags, p);
 155         frele(fp);
 156         return (error);
 157 }
 158
 159 static __inline int
 160 fo_ioctl(struct file *fp, u_long com, caddr_t data, struct proc *p)
 161 {
 162         int error;
 163
 164         if ((error = fref(fp)) == -1)
 165                 return (EBADF);
 166         error = (*fp->f_ops->fo_ioctl)(fp, com, data, p);
 167         frele(fp);
 168         return (error);
 169 }
 170
 171 static __inline int
 172 fo_select(struct file *fp, int which, void *wql, struct proc *p)
 173 {
 174         int error;
 175
 176         error = (*fp->f_ops->fo_select)(fp, which, wql, p);
 177         return (error);
 178 }
 179
 180 static __inline int
 181 fo_close(struct file *fp, struct proc *p)
 182 {
 183
 184         return ((*fp->f_ops->fo_close)(fp, p));
 185 }
 186
 187 static __inline int
 188 fo_kqfilter(struct file *fp, struct knote *kn, struct proc *p)
 189 {
 190         return ((*fp->f_ops->fo_kqfilter)(fp, kn, p));
 191 }
 192
 193 __END_DECLS
 194
 195 #endif /* __APPLE_API_UNSTABLE */
 196
 197 #endif /* KERNEL */
 198
 199 #endif /* !_SYS_FILE_H_ */