gen.subproj/ttyname.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * Copyright (c) 1988, 1993
  24  *      The Regents of the University of California.  All rights reserved.
  25  *
  26  * Redistribution and use in source and binary forms, with or without
  27  * modification, are permitted provided that the following conditions
  28  * are met:
  29  * 1. Redistributions of source code must retain the above copyright
  30  *    notice, this list of conditions and the following disclaimer.
  31  * 2. Redistributions in binary form must reproduce the above copyright
  32  *    notice, this list of conditions and the following disclaimer in the
  33  *    documentation and/or other materials provided with the distribution.
  34  * 3. All advertising materials mentioning features or use of this software
  35  *    must display the following acknowledgement:
  36  *      This product includes software developed by the University of
  37  *      California, Berkeley and its contributors.
  38  * 4. Neither the name of the University nor the names of its contributors
  39  *    may be used to endorse or promote products derived from this software
  40  *    without specific prior written permission.
  41  *
  42  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  43  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  44  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  45  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  46  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  47  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  48  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  49  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  50  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  51  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  52  * SUCH DAMAGE.
  53  */
  54
  55
  56 #include <sys/types.h>
  57 #include <sys/stat.h>
  58 #include <sys/ioctl.h>
  59 #include <sys/termios.h>
  60
  61 #include <fcntl.h>
  62 #include <dirent.h>
  63 #include <db.h>
  64 #include <string.h>
  65 #include <paths.h>
  66
  67 static char buf[sizeof(_PATH_DEV) + MAXNAMLEN] = _PATH_DEV;
  68 static char *oldttyname __P((int, struct stat *));
  69
  70 char *
  71 ttyname(fd)
  72         int fd;
  73 {
  74         struct stat sb;
  75         struct termios term;
  76         DB *db;
  77         DBT data, key;
  78         struct {
  79                 mode_t type;
  80                 dev_t dev;
  81         } bkey;
  82
  83         /* Must be a terminal. */
  84         if (ioctl(fd, TIOCGETA, &term) < 0)
  85                 return (NULL);
  86         /* Must be a character device. */
  87         if (fstat(fd, &sb) || !S_ISCHR(sb.st_mode))
  88                 return (NULL);
  89
  90         db = dbopen(_PATH_DEVDB, O_RDONLY, 0, DB_HASH, NULL);
  91         if (db) {
  92                 memset(&bkey, 0, sizeof(bkey));
  93                 bkey.type = S_IFCHR;
  94                 bkey.dev = sb.st_rdev;
  95                 key.data = &bkey;
  96                 key.size = sizeof(bkey);
  97                 if (!(db->get)(db, &key, &data, 0)) {
  98                         bcopy(data.data,
  99                             buf + sizeof(_PATH_DEV) - 1, data.size);
 100                         (void)(db->close)(db);
 101                         return (buf);
 102                 }
 103                 (void)(db->close)(db);
 104         }
 105         return (oldttyname(fd, &sb));
 106 }
 107
 108 static char *
 109 oldttyname(fd, sb)
 110         int fd;
 111         struct stat *sb;
 112 {
 113         register struct dirent *dirp;
 114         register DIR *dp;
 115         struct stat dsb;
 116
 117         if ((dp = opendir(_PATH_DEV)) == NULL)
 118                 return (NULL);
 119
 120         while ( (dirp = readdir(dp)) ) {
 121                 if (dirp->d_fileno != sb->st_ino)
 122                         continue;
 123                 bcopy(dirp->d_name, buf + sizeof(_PATH_DEV) - 1,
 124                     dirp->d_namlen + 1);
 125                 if (stat(buf, &dsb) || sb->st_dev != dsb.st_dev ||
 126                     sb->st_ino != dsb.st_ino)
 127                         continue;
 128                 (void)closedir(dp);
 129                 return (buf);
 130         }
 131         (void)closedir(dp);
 132         return (NULL);
 133 }