FreeBSD/Linux Kernel Cross Reference
sys/bsd/sys/filedesc.h

     /*
      * Copyright (c) 2000-2003 Apple Computer, Inc. All rights reserved.
      *
      * @APPLE_LICENSE_HEADER_START@
      * 
      * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
      * 
      * This file contains Original Code and/or Modifications of Original Code
      * as defined in and that are subject to the Apple Public Source License
     * Version 2.0 (the 'License'). You may not use this file except in
     * compliance with the License. Please obtain a copy of the License at
     * http://www.opensource.apple.com/apsl/ and read it before using this
     * file.
     * 
     * The Original Code and all software distributed under the License are
     * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
     * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
     * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
     * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
     * Please see the License for the specific language governing rights and
     * limitations under the License.
     * 
     * @APPLE_LICENSE_HEADER_END@
     */
    /* Copyright (c) 1995, 1997 Apple Computer, Inc. All Rights Reserved */
    /*
     * Copyright (c) 1990, 1993
     *      The Regents of the University of California.  All rights reserved.
     *
     * Redistribution and use in source and binary forms, with or without
     * modification, are permitted provided that the following conditions
     * are met:
     * 1. Redistributions of source code must retain the above copyright
     *    notice, this list of conditions and the following disclaimer.
     * 2. Redistributions in binary form must reproduce the above copyright
     *    notice, this list of conditions and the following disclaimer in the
     *    documentation and/or other materials provided with the distribution.
     * 3. All advertising materials mentioning features or use of this software
     *    must display the following acknowledgement:
     *      This product includes software developed by the University of
     *      California, Berkeley and its contributors.
     * 4. Neither the name of the University nor the names of its contributors
     *    may be used to endorse or promote products derived from this software
     *    without specific prior written permission.
     *
     * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     * SUCH DAMAGE.
     *
     *      @(#)filedesc.h  8.1 (Berkeley) 6/2/93
     */
    
    #ifndef _SYS_FILEDESC_H_
    #define _SYS_FILEDESC_H_
    
    #include <sys/appleapiopts.h>
    
    #ifdef __APPLE_API_UNSTABLE
    /*
     * This structure is used for the management of descriptors.  It may be
     * shared by multiple processes.
     *
     * A process is initially started out with NDFILE descriptors [XXXstored within
     * this structureXXX], selected to be enough for typical applications based on
     * the historical limit of 20 open files (and the usage of descriptors by
     * shells).  If these descriptors are exhausted, a larger descriptor table
     * may be allocated, up to a process' resource limit; [XXXthe internal arrays
     * are then unusedXXX].  The initial expansion is set to NDEXTENT; each time
     * it runs out, it is doubled until the resource limit is reached. NDEXTENT
     * should be selected to be the biggest multiple of OFILESIZE (see below)
     * that will fit in a power-of-two sized piece of memory.
     */
    #define NDFILE          25              /* 125 bytes */
    #define NDEXTENT        50              /* 250 bytes in 256-byte alloc. */ 
    
    struct klist;
    
    struct filedesc {
            struct  file **fd_ofiles;       /* file structures for open files */
            char    *fd_ofileflags;         /* per-process open file flags */
            struct  vnode *fd_cdir;         /* current directory */
            struct  vnode *fd_rdir;         /* root directory */
            int     fd_nfiles;              /* number of open files allocated */
            u_short fd_lastfile;            /* high-water mark of fd_ofiles */
            u_short fd_freefile;            /* approx. next free file */
            u_short fd_cmask;               /* mask for file creation */
            u_short fd_refcnt;              /* reference count */
    
            int     fd_knlistsize;          /* size of knlist */
            struct  klist *fd_knlist;       /* list of attached knotes */
            u_long  fd_knhashmask;          /* size of knhash */
           struct  klist *fd_knhash;       /* hash table for attached knotes */
   };
   
   /*
    * Per-process open flags.
    */
   #define UF_EXCLOSE      0x01            /* auto-close on exec */
   #define UF_MAPPED       0x02            /* mapped from device */
   #define UF_RESERVED     0x04            /* open pending / in progress */
   
   /*
    * Storage required per open file descriptor.
    */
   #define OFILESIZE (sizeof(struct file *) + sizeof(char))
   
   #ifdef KERNEL
   /*
    * Kernel global variables and routines.
    */
   extern int      dupfdopen __P((struct filedesc *fdp,
                                   int indx, int dfd, int mode, int error));
   extern int      fdalloc __P((struct proc *p, int want, int *result));
   extern void     fdrelse __P((struct proc *p, int fd));
   extern int      fdavail __P((struct proc *p, int n));
   extern int      fdgetf __P((struct proc *p, int fd, struct file **resultfp));
   #define         fdfile(p, fd)                                   \
                           (&(p)->p_fd->fd_ofiles[(fd)])
   #define         fdflags(p, fd)                                  \
                           (&(p)->p_fd->fd_ofileflags[(fd)])
   extern int      falloc __P((struct proc *p,
                                   struct file **resultfp, int *resultfd));
   extern void     ffree __P((struct file *fp));
   
   #ifdef __APPLE_API_PRIVATE
   extern struct   filedesc *fdcopy __P((struct proc *p));
   extern void     fdfree __P((struct proc *p));
   extern void     fdexec __P((struct proc *p));
   #endif /* __APPLE_API_PRIVATE */
   
   #endif /* KERNEL */
   
   #endif /* __APPLE_API_UNSTABLE */
   
   #endif /* !_SYS_FILEDESC_H_ */

Cache object: 4adcf405218d2e54b1f4dd6fb983915b