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 #ifndef lint 33 #endif /* not lint */ 34 35 #include "namespace.h" 36 #include <sys/param.h> 37 #include <sys/ioctl.h> 38 39 #include <errno.h> 40 #include <paths.h> 41 #include <stdlib.h> 42 #include <string.h> 43 #include "un-namespace.h" 44 45 /* 46 * __isptmaster(): return whether the file descriptor refers to a 47 * pseudo-terminal master device. 48 */ 49 static int 50 __isptmaster(int fildes) 51 { 52 53 if (_ioctl(fildes, TIOCPTMASTER) == 0) 54 return (0); 55 56 if (errno != EBADF) 57 errno = EINVAL; 58 59 return (-1); 60 } 61 62 /* 63 * In our implementation, grantpt() and unlockpt() don't actually have 64 * any use, because PTY's are created on the fly and already have proper 65 * permissions upon creation. 66 * 67 * Just make sure `fildes' actually points to a real PTY master device. 68 */ 69 __strong_reference(__isptmaster, grantpt); 70 __strong_reference(__isptmaster, unlockpt); 71 72 /* 73 * ptsname_r(): return the pathname of the slave pseudo-terminal device 74 * associated with the specified master. 75 */ 76 int 77 __ptsname_r(int fildes, char *buffer, size_t buflen) 78 { 79 80 if (buflen <= sizeof(_PATH_DEV)) { 81 errno = ERANGE; 82 return (-1); 83 } 84 85 /* Make sure fildes points to a master device. */ 86 if (__isptmaster(fildes) != 0) 87 return (-1); 88 89 memcpy(buffer, _PATH_DEV, sizeof(_PATH_DEV)); 90 buffer += sizeof(_PATH_DEV) - 1; 91 buflen -= sizeof(_PATH_DEV) - 1; 92 93 if (fdevname_r(fildes, buffer, buflen) == NULL) { 94 if (errno == EINVAL) 95 errno = ERANGE; 96 return (-1); 97 } 98 99 return (0); 100 } 101 102 __strong_reference(__ptsname_r, ptsname_r); 103 104 /* 105 * ptsname(): return the pathname of the slave pseudo-terminal device 106 * associated with the specified master. 107 */ 108 char * 109 ptsname(int fildes) 110 { 111 static char pt_slave[sizeof(_PATH_DEV) + SPECNAMELEN]; 112 113 if (__ptsname_r(fildes, pt_slave, sizeof(pt_slave)) == 0) 114 return (pt_slave); 115 116 return (NULL); 117 } 118