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