bsd/sys/file.h

   1 /*
   2  * Copyright (c) 2000-2002 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 /* Copyright (c) 1995, 1997 Apple Computer, Inc. All Rights Reserved */
  26 /*
  27  * Copyright (c) 1982, 1986, 1989, 1993
  28  *      The Regents of the University of California.  All rights reserved.
  29  *
  30  * Redistribution and use in source and binary forms, with or without
  31  * modification, are permitted provided that the following conditions
  32  * are met:
  33  * 1. Redistributions of source code must retain the above copyright
  34  *    notice, this list of conditions and the following disclaimer.
  35  * 2. Redistributions in binary form must reproduce the above copyright
  36  *    notice, this list of conditions and the following disclaimer in the
  37  *    documentation and/or other materials provided with the distribution.
  38  * 3. All advertising materials mentioning features or use of this software
  39  *    must display the following acknowledgement:
  40  *      This product includes software developed by the University of
  41  *      California, Berkeley and its contributors.
  42  * 4. Neither the name of the University nor the names of its contributors
  43  *    may be used to endorse or promote products derived from this software
  44  *    without specific prior written permission.
  45  *
  46  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  47  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  48  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  49  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  50  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  51  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  52  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  53  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  54  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  55  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  56  * SUCH DAMAGE.
  57  *
  58  *      @(#)file.h      8.3 (Berkeley) 1/9/95
  59  */
  60
  61 #ifndef _SYS_FILE_H_
  62 #define _SYS_FILE_H_
  63
  64 #include <sys/appleapiopts.h>
  65 #include <sys/fcntl.h>
  66 #include <sys/unistd.h>
  67
  68 #ifdef KERNEL
  69 #include <sys/errno.h>
  70 #include <sys/queue.h>
  71 #include <sys/cdefs.h>
  72
  73 struct proc;
  74 struct uio;
  75 struct knote;
  76 #ifdef __APPLE_API_UNSTABLE
  77
  78 /*
  79  * Kernel descriptor table.
  80  * One entry for each open kernel vnode and socket.
  81  */
  82 struct file {
  83         LIST_ENTRY(file) f_list;/* list of active files */
  84         short   f_flag;         /* see fcntl.h */
  85 #define DTYPE_VNODE     1       /* file */
  86 #define DTYPE_SOCKET    2       /* communications endpoint */
  87 #define DTYPE_PSXSHM    3       /* POSIX Shared memory */
  88 #define DTYPE_PSXSEM    4       /* POSIX Semaphores */
  89 #define DTYPE_KQUEUE    5       /* kqueue */
  90         short   f_type;         /* descriptor type */
  91         short   f_count;        /* reference count */
  92         short   f_msgcount;     /* references from message queue */
  93         struct  ucred *f_cred;  /* credentials associated with descriptor */
  94         struct  fileops {
  95                 int     (*fo_read)      __P((struct file *fp, struct uio *uio,
  96                                             struct ucred *cred, int flags,
  97                                             struct proc *p));
  98                 int     (*fo_write)     __P((struct file *fp, struct uio *uio,
  99                                             struct ucred *cred, int flags,
 100                                             struct proc *p));
 101 #define FOF_OFFSET      1
 102                 int     (*fo_ioctl)     __P((struct file *fp, u_long com,
 103                                             caddr_t data, struct proc *p));
 104                 int     (*fo_select)    __P((struct file *fp, int which,
 105                                                 void *wql, struct proc *p));
 106                 int     (*fo_close)     __P((struct file *fp, struct proc *p));
 107                 int     (*fo_kqfilter)  __P((struct file *fp, struct knote *kn,
 108                                              struct proc *p));
 109         } *f_ops;
 110         off_t   f_offset;
 111         caddr_t f_data;         /* vnode or socket or SHM or semaphore */
 112 };
 113
 114 #ifdef __APPLE_API_PRIVATE
 115 LIST_HEAD(filelist, file);
 116 extern struct filelist filehead;        /* head of list of open files */
 117 extern int maxfiles;                    /* kernel limit on number of open files */
 118 extern int nfiles;                      /* actual number of open files */
 119 #endif /* __APPLE_API_PRIVATE */
 120
 121 __BEGIN_DECLS
 122 int fref __P((struct file *));  /* take a reference on file pointer */
 123 int frele __P((struct file *)); /* release a reference on file pointer */
 124 int fcount __P((struct file *));        /* returns the reference count */
 125
 126 static __inline int fo_read __P((struct file *fp, struct uio *uio,
 127         struct ucred *cred, int flags, struct proc *p));
 128 static __inline int fo_write __P((struct file *fp, struct uio *uio,
 129         struct ucred *cred, int flags, struct proc *p));
 130 static __inline int fo_ioctl __P((struct file *fp, u_long com, caddr_t data,
 131         struct proc *p));
 132 static __inline int fo_select __P((struct file *fp, int which, void *wql,
 133         struct proc *p));
 134 static __inline int fo_close __P((struct file *fp, struct proc *p));
 135 static __inline int fo_kqfilter __P((struct file *fp, struct knote *kn,
 136         struct proc *p));
 137
 138 static __inline int
 139 fo_read(struct file *fp, struct uio *uio, struct ucred *cred, int flags, struct proc *p)
 140 {
 141         int error;
 142
 143         if ((error = fref(fp)) == -1)
 144                 return (EBADF);
 145         error = (*fp->f_ops->fo_read)(fp, uio, cred, flags, p);
 146         frele(fp);
 147         return (error);
 148 }
 149
 150 static __inline int
 151 fo_write(struct file *fp, struct uio *uio, struct ucred *cred, int flags, struct proc *p)
 152 {
 153         int error;
 154
 155         if ((error = fref(fp)) == -1)
 156                 return (EBADF);
 157         error = (*fp->f_ops->fo_write)(fp, uio, cred, flags, p);
 158         frele(fp);
 159         return (error);
 160 }
 161
 162 static __inline int
 163 fo_ioctl(struct file *fp, u_long com, caddr_t data, struct proc *p)
 164 {
 165         int error;
 166
 167         if ((error = fref(fp)) == -1)
 168                 return (EBADF);
 169         error = (*fp->f_ops->fo_ioctl)(fp, com, data, p);
 170         frele(fp);
 171         return (error);
 172 }
 173
 174 static __inline int
 175 fo_select(struct file *fp, int which, void *wql, struct proc *p)
 176 {
 177         int error;
 178
 179         error = (*fp->f_ops->fo_select)(fp, which, wql, p);
 180         return (error);
 181 }
 182
 183 static __inline int
 184 fo_close(struct file *fp, struct proc *p)
 185 {
 186
 187         return ((*fp->f_ops->fo_close)(fp, p));
 188 }
 189
 190 static __inline int
 191 fo_kqfilter(struct file *fp, struct knote *kn, struct proc *p)
 192 {
 193         return ((*fp->f_ops->fo_kqfilter)(fp, kn, p));
 194 }
 195
 196 __END_DECLS
 197
 198 #endif /* __APPLE_API_UNSTABLE */
 199
 200 #endif /* KERNEL */
 201
 202 #endif /* !_SYS_FILE_H_ */