1 /*- 2 * Copyright (c) 1990, 1993, 1994 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)pty.c 8.3 (Berkeley) 5/16/94 34 * $FreeBSD: src/lib/libutil/pty.c,v 1.10 1999/08/28 00:05:51 peter Exp $ 35 * $DragonFly: src/lib/libutil/pty.c,v 1.3 2004/10/25 19:39:09 drhodus Exp $ 36 */ 37 38 #include <sys/types.h> 39 #include <sys/ioctl.h> 40 #include <sys/stat.h> 41 42 #include <errno.h> 43 #include <fcntl.h> 44 #include <grp.h> 45 #include <stdlib.h> 46 #include <string.h> 47 #include <termios.h> 48 #include <unistd.h> 49 #include <libutil.h> 50 51 int 52 openpty(amaster, aslave, name, termp, winp) 53 int *amaster, *aslave; 54 char *name; 55 struct termios *termp; 56 struct winsize *winp; 57 { 58 char line[] = "/dev/ptyXX"; 59 const char *cp1, *cp2; 60 int master, slave, ttygid; 61 struct group *gr; 62 63 if ((gr = getgrnam("tty")) != NULL) 64 ttygid = gr->gr_gid; 65 else 66 ttygid = -1; 67 68 for (cp1 = "pqrsPQRS"; *cp1; cp1++) { 69 line[8] = *cp1; 70 for (cp2 = "0123456789abcdefghijklmnopqrstuv"; *cp2; cp2++) { 71 line[5] = 'p'; 72 line[9] = *cp2; 73 if ((master = open(line, O_RDWR, 0)) == -1) { 74 if (errno == ENOENT) 75 return (-1); /* out of ptys */ 76 } else { 77 line[5] = 't'; 78 (void) chown(line, getuid(), ttygid); 79 (void) chmod(line, S_IRUSR|S_IWUSR|S_IWGRP); 80 (void) revoke(line); 81 if ((slave = open(line, O_RDWR, 0)) != -1) { 82 *amaster = master; 83 *aslave = slave; 84 if (name) 85 strcpy(name, line); 86 if (termp) 87 (void) tcsetattr(slave, 88 TCSAFLUSH, termp); 89 if (winp) 90 (void) ioctl(slave, TIOCSWINSZ, 91 (char *)winp); 92 return (0); 93 } 94 (void) close(master); 95 } 96 } 97 } 98 errno = ENOENT; /* out of ptys */ 99 return (-1); 100 } 101 102 int 103 forkpty(amaster, name, termp, winp) 104 int *amaster; 105 char *name; 106 struct termios *termp; 107 struct winsize *winp; 108 { 109 int master, slave, pid; 110 111 if (openpty(&master, &slave, name, termp, winp) == -1) 112 return (-1); 113 switch (pid = fork()) { 114 case -1: 115 return (-1); 116 case 0: 117 /* 118 * child 119 */ 120 (void) close(master); 121 login_tty(slave); 122 return (0); 123 } 124 /* 125 * parent 126 */ 127 *amaster = master; 128 (void) close(slave); 129 return (pid); 130 } 131