StdLib/Include/sys/file.h

   1 /*
   2  * Copyright (c) 1982, 1986, 1989, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  *      @(#)file.h      8.3 (Berkeley) 1/9/95
  34  * $Id: file.h,v 1.1.1.1 2006/05/30 06:12:53 hhzhou Exp $
  35  */
  36
  37 #ifndef _SYS_FILE_H_
  38 #define _SYS_FILE_H_
  39
  40 #ifndef KERNEL
  41 #include <sys/fcntl.h>
  42 #include <sys/unistd.h>
  43 #endif
  44
  45 #ifdef KERNEL
  46 #include <sys/queue.h>
  47
  48 struct proc;
  49 struct uio;
  50
  51 /*
  52  * Kernel descriptor table.
  53  * One entry for each open kernel vnode and socket.
  54  */
  55 struct file {
  56         LIST_ENTRY(file) f_list;/* list of active files */
  57         short   f_flag;         /* see fcntl.h */
  58 #define DTYPE_VNODE     1       /* file */
  59 #define DTYPE_SOCKET    2       /* communications endpoint */
  60 #define DTYPE_PIPE      3       /* pipe */
  61 #define DTYPE_FIFO      4       /* fifo (named pipe) */
  62         short   f_type;         /* descriptor type */
  63         short   f_count;        /* reference count */
  64         short   f_msgcount;     /* references from message queue */
  65         struct  ucred *f_cred;  /* credentials associated with descriptor */
  66         struct  fileops {
  67                 int     (*fo_read)      __P((struct file *fp, struct uio *uio,
  68                                             struct ucred *cred, int flags));
  69                 int     (*fo_write)     __P((struct file *fp, struct uio *uio,
  70                                             struct ucred *cred, int flags));
  71 #define FOF_OFFSET      1
  72                 int     (*fo_ioctl)     __P((struct file *fp, u_long com,
  73                                             caddr_t data, struct proc *p));
  74                 int     (*fo_poll)      __P((struct file *fp, int events,
  75                                             struct ucred *cred, struct proc *p));
  76                 int     (*fo_close)     __P((struct file *fp, struct proc *p));
  77         } *f_ops;
  78         int     f_seqcount;     /*
  79                                  * count of sequential accesses -- cleared
  80                                  * by most seek operations.
  81                                  */
  82         off_t   f_nextread;     /*
  83                                  * offset of next expected read
  84                                  */
  85         off_t   f_offset;
  86         caddr_t f_data;         /* vnode or socket */
  87 };
  88
  89 #ifdef MALLOC_DECLARE
  90 MALLOC_DECLARE(M_FILE);
  91 #endif
  92
  93 LIST_HEAD(filelist, file);
  94 extern struct filelist filehead; /* head of list of open files */
  95 extern struct fileops vnops;
  96 extern int maxfiles;            /* kernel limit on number of open files */
  97 extern int maxfilesperproc;     /* per process limit on number of open files */
  98 extern int nfiles;              /* actual number of open files */
  99
 100 #endif /* KERNEL */
 101
 102 #endif /* !SYS_FILE_H */