1 /* 2 * Copyright (c) 2009 The DragonFly Project. All rights reserved. 3 * 4 * This code is derived from software contributed to The DragonFly Project 5 * by Alex Hornung <ahornung@gmail.com> 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in 15 * the documentation and/or other materials provided with the 16 * distribution. 17 * 3. Neither the name of The DragonFly Project nor the names of its 18 * contributors may be used to endorse or promote products derived 19 * from this software without specific, prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 #include "namespace.h" 35 #include <sys/types.h> 36 #include <fcntl.h> 37 #include <dirent.h> 38 #include <stdlib.h> 39 #include <termios.h> 40 #include <unistd.h> 41 #include <string.h> 42 #include <paths.h> 43 #include <errno.h> 44 #include <machine/stdint.h> 45 #include <sys/stat.h> 46 #include <sys/ioctl.h> 47 #include "reentrant.h" 48 #include "un-namespace.h" 49 50 #include "libc_private.h" 51 52 static char fdevname_buf[sizeof(_PATH_DEV) + NAME_MAX]; 53 54 static once_t fdevname_init_once = ONCE_INITIALIZER; 55 static thread_key_t fdevname_key; 56 static int fdevname_keycreated = 0; 57 58 int 59 fdevname_r(int fd, char *buf, size_t len) 60 { 61 struct stat sb; 62 struct fiodname_args fa; 63 size_t used; 64 65 *buf = '\0'; 66 67 /* Must be a character device. */ 68 if (_fstat(fd, &sb) || !S_ISCHR(sb.st_mode)) 69 return (ENOTTY); 70 71 /* Must have enough room */ 72 if (len <= sizeof(_PATH_DEV)) 73 return (ERANGE); 74 75 strcpy(buf, _PATH_DEV); 76 used = strlen(buf); 77 fa.len = len - used; 78 fa.name = buf + used; 79 if (_ioctl(fd, FIODNAME, &fa) == -1) { 80 return ERANGE; 81 } 82 return (0); 83 } 84 85 static void 86 fdevname_keycreate(void) 87 { 88 fdevname_keycreated = (thr_keycreate(&fdevname_key, free) == 0); 89 } 90 91 char * 92 fdevname(int fd) 93 { 94 char *buf; 95 96 if (thr_main() != 0) 97 buf = fdevname_buf; 98 else { 99 if (thr_once(&fdevname_init_once, fdevname_keycreate) != 0 || 100 !fdevname_keycreated) 101 return (NULL); 102 if ((buf = thr_getspecific(fdevname_key)) == NULL) { 103 if ((buf = malloc(sizeof fdevname_buf)) == NULL) 104 return (NULL); 105 if (thr_setspecific(fdevname_key, buf) != 0) { 106 free(buf); 107 return (NULL); 108 } 109 } 110 } 111 112 if (fdevname_r(fd, buf, sizeof fdevname_buf) != 0) 113 return (NULL); 114 return (buf); 115 } 116