1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2008 Ed Schouten <ed@FreeBSD.org> 5 * All rights reserved. 6 * 7 * Portions of this software were developed under sponsorship from Snow 8 * B.V., the Netherlands. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include "namespace.h" 33 #include <sys/param.h> 34 #include <sys/ioctl.h> 35 36 #include <errno.h> 37 #include <paths.h> 38 #include <stdlib.h> 39 #include <string.h> 40 #include "un-namespace.h" 41 42 /* 43 * __isptmaster(): return whether the file descriptor refers to a 44 * pseudo-terminal master device. 45 */ 46 static int 47 __isptmaster(int fildes) 48 { 49 50 if (_ioctl(fildes, TIOCPTMASTER) == 0) 51 return (0); 52 53 if (errno != EBADF) 54 errno = EINVAL; 55 56 return (-1); 57 } 58 59 /* 60 * In our implementation, grantpt() and unlockpt() don't actually have 61 * any use, because PTY's are created on the fly and already have proper 62 * permissions upon creation. 63 * 64 * Just make sure `fildes' actually points to a real PTY master device. 65 */ 66 __strong_reference(__isptmaster, grantpt); 67 __strong_reference(__isptmaster, unlockpt); 68 69 /* 70 * ptsname_r(): return the pathname of the slave pseudo-terminal device 71 * associated with the specified master. 72 */ 73 int 74 __ptsname_r(int fildes, char *buffer, size_t buflen) 75 { 76 77 if (buflen <= sizeof(_PATH_DEV)) { 78 errno = ERANGE; 79 return (-1); 80 } 81 82 /* Make sure fildes points to a master device. */ 83 if (__isptmaster(fildes) != 0) 84 return (-1); 85 86 memcpy(buffer, _PATH_DEV, sizeof(_PATH_DEV)); 87 buffer += sizeof(_PATH_DEV) - 1; 88 buflen -= sizeof(_PATH_DEV) - 1; 89 90 if (fdevname_r(fildes, buffer, buflen) == NULL) { 91 if (errno == EINVAL) 92 errno = ERANGE; 93 return (-1); 94 } 95 96 return (0); 97 } 98 99 __strong_reference(__ptsname_r, ptsname_r); 100 101 /* 102 * ptsname(): return the pathname of the slave pseudo-terminal device 103 * associated with the specified master. 104 */ 105 char * 106 ptsname(int fildes) 107 { 108 static char pt_slave[sizeof(_PATH_DEV) + SPECNAMELEN]; 109 110 if (__ptsname_r(fildes, pt_slave, sizeof(pt_slave)) == 0) 111 return (pt_slave); 112 113 return (NULL); 114 } 115