FreeBSD/Linux Kernel Cross Reference
sys/kern/tty_bsdpty.c

     /*      $NetBSD: tty_bsdpty.c,v 1.3.2.1 2006/04/04 22:14:44 tron Exp $  */
     
     /*-
      * Copyright (c) 2004 The NetBSD Foundation, Inc.
      * 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 NetBSD
     *        Foundation, Inc. and its contributors.
     * 4. Neither the name of The NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
     */
    
    #include <sys/cdefs.h>
    __KERNEL_RCSID(0, "$NetBSD: tty_bsdpty.c,v 1.3.2.1 2006/04/04 22:14:44 tron Exp $");
    
    #include "opt_ptm.h"
    
    #ifdef COMPAT_BSDPTY
    /* bsd tty implementation for pty multiplexor driver /dev/ptm{,x} */
    
    #include <sys/param.h>
    #include <sys/systm.h>
    #include <sys/ioctl.h>
    #include <sys/proc.h>
    #include <sys/tty.h>
    #include <sys/stat.h>
    #include <sys/file.h>
    #include <sys/uio.h>
    #include <sys/kernel.h>
    #include <sys/vnode.h>
    #include <sys/namei.h>
    #include <sys/signalvar.h>
    #include <sys/uio.h>
    #include <sys/filedesc.h>
    #include <sys/conf.h>
    #include <sys/poll.h>
    #include <sys/malloc.h>
    #include <sys/pty.h>
    
    /*
     * pts == /dev/tty[pqrs]?
     * ptc == /dev/pty[pqrs]?
     */
    
    /*
     * All this hard-coding is really evil.
     */
    #define TTY_GID         4
    #define TTY_PERM        (S_IRUSR|S_IWUSR|S_IWGRP)
    #define TTY_TEMPLATE    "/dev/XtyXX"
    #define TTY_NAMESIZE    sizeof(TTY_TEMPLATE)
    #define TTY_LETTERS     "pqrstuvwxyzPQRST"
    #define TTY_OLD_SUFFIX  "0123456789abcdef"
    #define TTY_NEW_SUFFIX  "ghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
    
    static int pty_makename(struct ptm_pty *, char *, size_t, dev_t, char);
    static int pty_allocvp(struct ptm_pty *, struct proc *, struct vnode **,
        dev_t, char);
    static void pty_getvattr(struct ptm_pty *, struct proc *, struct vattr *);
    
    struct ptm_pty ptm_bsdpty = {
            pty_allocvp,
            pty_makename,
            pty_getvattr,
            NULL
    };
    
    static int
    /*ARGSUSED*/
    pty_makename(struct ptm_pty *ptm, char *bf, size_t bufsiz, dev_t dev, char c)
    {
            size_t nt;
            dev_t minor = minor(dev);
            const char *suffix;
    
            if (bufsiz < TTY_NAMESIZE)
                   return EINVAL;
   
           (void)memcpy(bf, TTY_TEMPLATE, TTY_NAMESIZE);
   
           if (minor < 256) {
                   suffix = TTY_OLD_SUFFIX;
                   nt = sizeof(TTY_OLD_SUFFIX) - 1;
           } else {
                   minor -= 256;
                   suffix = TTY_NEW_SUFFIX;
                   nt = sizeof(TTY_NEW_SUFFIX) - 1;
           }
   
           bf[5] = c;
           bf[8] = TTY_LETTERS[minor / nt];
           bf[9] = suffix[minor % nt];
           return 0;
   }
   
   
   static int
   /*ARGSUSED*/
   pty_allocvp(struct ptm_pty *ptm, struct proc *p, struct vnode **vp, dev_t dev,
       char ms)
   {
           int error;
           struct nameidata nd;
           char name[TTY_NAMESIZE];
   
           error = (*ptm->makename)(ptm, name, sizeof(name), dev, ms);
           if (error)
                   return error;
   
           NDINIT(&nd, LOOKUP, NOFOLLOW|LOCKLEAF, UIO_SYSSPACE, name, p);
           if ((error = namei(&nd)) != 0)
                   return error;
           *vp = nd.ni_vp;
           return 0;
   }
   
   
   static void
   /*ARGSUSED*/
   pty_getvattr(struct ptm_pty *ptm, struct proc *p, struct vattr *vattr)
   {
           VATTR_NULL(vattr);
           /* get real uid */
           vattr->va_uid = p->p_cred->p_ruid;
           vattr->va_gid = TTY_GID;
           vattr->va_mode = TTY_PERM;
   }
   #endif

Cache object: 04c15f84cd8482df722d8fd13223a00c