1 /* 2 * Copyright (c) 1983, 1993 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 34 #if defined(LIBC_SCCS) && !defined(lint) 35 static char sccsid[] = "@(#)opendir.c 8.2 (Berkeley) 2/12/94"; 36 #endif /* LIBC_SCCS and not lint */ 37 38 #include <sys/param.h> 39 40 #include <dirent.h> 41 #include <fcntl.h> 42 #include <stdlib.h> 43 #include <unistd.h> 44 45 /* 46 * open a directory. 47 */ 48 DIR * 49 opendir(name) 50 const char *name; 51 { 52 register DIR *dirp; 53 register int fd; 54 55 if ((fd = open(name, 0)) == -1) 56 return NULL; 57 if (fcntl(fd, F_SETFD, FD_CLOEXEC) == -1 || 58 (dirp = (DIR *)malloc(sizeof(DIR))) == NULL) { 59 close (fd); 60 return NULL; 61 } 62 /* 63 * If CLBYTES is an exact multiple of DIRBLKSIZ, use a CLBYTES 64 * buffer that it cluster boundary aligned. 65 * Hopefully this can be a big win someday by allowing page trades 66 * to user space to be done by getdirentries() 67 */ 68 if ((CLBYTES % DIRBLKSIZ) == 0) { 69 dirp->dd_buf = malloc(CLBYTES); 70 dirp->dd_len = CLBYTES; 71 } else { 72 dirp->dd_buf = malloc(DIRBLKSIZ); 73 dirp->dd_len = DIRBLKSIZ; 74 } 75 if (dirp->dd_buf == NULL) { 76 close (fd); 77 return NULL; 78 } 79 dirp->dd_fd = fd; 80 dirp->dd_loc = 0; 81 dirp->dd_seek = 0; 82 /* 83 * Set up seek point for rewinddir. 84 */ 85 dirp->dd_rewind = telldir(dirp); 86 return dirp; 87 } 88