gonzui

    1: /*      $OpenBSD: file.h,v 1.28 2011/06/28 10:15:38 thib Exp $       */
    2: /*      $NetBSD: file.h,v 1.11 1995/03/26 20:24:13 jtc Exp $ */
    3: 
    4: /*
    5:  * Copyright (c) 1982, 1986, 1989, 1993
    6:  *      The Regents of the University of California.  All rights reserved.
    7:  *
    8:  * Redistribution and use in source and binary forms, with or without
    9:  * modification, are permitted provided that the following conditions
   10:  * are met:
   11:  * 1. Redistributions of source code must retain the above copyright
   12:  *    notice, this list of conditions and the following disclaimer.
   13:  * 2. Redistributions in binary form must reproduce the above copyright
   14:  *    notice, this list of conditions and the following disclaimer in the
   15:  *    documentation and/or other materials provided with the distribution.
   16:  * 3. Neither the name of the University nor the names of its contributors
   17:  *    may be used to endorse or promote products derived from this software
   18:  *    without specific prior written permission.
   19:  *
   20:  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   21:  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   22:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   23:  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   24:  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   25:  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   26:  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   27:  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   28:  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   29:  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   30:  * SUCH DAMAGE.
   31:  *
   32:  *      @(#)file.h   8.2 (Berkeley) 8/20/94
   33:  */
   34: 
   35: #include <sys/fcntl.h>
   36: #include <sys/unistd.h>
   37: 
   38: #ifdef _KERNEL
   39: #include <sys/queue.h>
   40: 
   41: struct proc;
   42: struct uio;
   43: struct knote;
   44: struct stat;
   45: struct file;
   46: 
   47: struct  fileops {
   48:         int    (*fo_read)(struct file *, off_t *, struct uio *,
   49:                     struct ucred *);
   50:         int    (*fo_write)(struct file *, off_t *, struct uio *,
   51:                     struct ucred *);
   52:         int    (*fo_ioctl)(struct file *, u_long, caddr_t,
   53:                     struct proc *);
   54:         int    (*fo_poll)(struct file *, int, struct proc *);
   55:         int    (*fo_kqfilter)(struct file *, struct knote *);
   56:         int    (*fo_stat)(struct file *, struct stat *, struct proc *);
   57:         int    (*fo_close)(struct file *, struct proc *);
   58: };
   59: 
   60: /*
   61:  * Kernel descriptor table.
   62:  * One entry for each open kernel vnode and socket.
   63:  */
   64: struct file {
   65:         LIST_ENTRY(file) f_list;/* list of active files */
   66:         short  f_flag;          /* see fcntl.h */
   67: #define DTYPE_VNODE     1   /* file */
   68: #define DTYPE_SOCKET    2  /* communications endpoint */
   69: #define DTYPE_PIPE      3    /* pipe */
   70: #define DTYPE_KQUEUE    4  /* event queue */
   71: #define DTYPE_CRYPTO    5  /* crypto */
   72: #define DTYPE_SYSTRACE  6        /* system call tracing */
   73:         short  f_type;          /* descriptor type */
   74:         long   f_count;  /* reference count */
   75:         long   f_msgcount;       /* references from message queue */
   76:         struct ucred *f_cred;  /* credentials associated with descriptor */
   77:         struct fileops *f_ops;
   78:         off_t  f_offset;
   79:         void   *f_data; /* private data */
   80:         int    f_iflags;  /* internal flags */
   81:         int    f_usecount;        /* number of users (temporary references). */
   82:         u_int64_t f_rxfer;     /* total number of read transfers */
   83:         u_int64_t f_wxfer;     /* total number of write transfers */
   84:         u_int64_t f_seek;      /* total independent seek operations */
   85:         u_int64_t f_rbytes;    /* total bytes read */
   86:         u_int64_t f_wbytes;    /* total bytes written */
   87: };
   88: 
   89: #define FIF_WANTCLOSE           0x01     /* a close is waiting for usecount */
   90: #define FIF_LARVAL              0x02        /* not fully constructed, don't use */
   91: #define FIF_MARK                0x04  /* mark during gc() */
   92: #define FIF_DEFER               0x08 /* defer for next gc() pass */
   93: 
   94: #define FILE_IS_USABLE(fp) \
   95:         (((fp)->f_iflags & (FIF_WANTCLOSE|FIF_LARVAL)) == 0)
   96: 
   97: #define FREF(fp) do { (fp)->f_usecount++; } while (0)
   98: #define FRELE(fp) do {                                  \
   99:         --(fp)->f_usecount;                                    \
  100:         if (((fp)->f_iflags & FIF_WANTCLOSE) != 0)             \
  101:                 wakeup(&(fp)->f_usecount);                    \
  102: } while (0)
  103: 
  104: #define FILE_SET_MATURE(fp) do {                                \
  105:         (fp)->f_iflags &= ~FIF_LARVAL;                         \
  106:         FRELE(fp);                                             \
  107: } while (0)
  108: 
  109: LIST_HEAD(filelist, file);
  110: extern struct filelist filehead;        /* head of list of open files */
  111: extern int maxfiles;                    /* kernel limit on number of open files */
  112: extern int nfiles;                      /* actual number of open files */
  113: extern struct fileops vnops;            /* vnode operations for files */
  114: 
  115: #endif /* _KERNEL */