1 /* 2 * Copyright 2000 Massachusetts Institute of Technology 3 * 4 * Permission to use, copy, modify, and distribute this software and 5 * its documentation for any purpose and without fee is hereby 6 * granted, provided that both the above copyright notice and this 7 * permission notice appear in all copies, that both the above 8 * copyright notice and this permission notice appear in all 9 * supporting documentation, and that the name of M.I.T. not be used 10 * in advertising or publicity pertaining to distribution of the 11 * software without specific, written prior permission. M.I.T. makes 12 * no representations about the suitability of this software for any 13 * purpose. It is provided "as is" without express or implied 14 * warranty. 15 * 16 * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS 17 * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE, 18 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT 20 * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF 23 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 25 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 26 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $FreeBSD: src/lib/libc/gen/posixshm.c,v 1.2.2.1 2000/08/22 01:48:12 jhb Exp $ 30 */ 31 32 #include "namespace.h" 33 #include <sys/types.h> 34 #include <sys/fcntl.h> 35 #include <sys/mman.h> 36 #include <sys/stat.h> 37 38 #include <errno.h> 39 #include <unistd.h> 40 #include "un-namespace.h" 41 42 int 43 shm_open(const char *path, int flags, mode_t mode) 44 { 45 int dfd; 46 int fd; 47 struct stat stab; 48 49 if ((flags & O_ACCMODE) == O_WRONLY) { 50 errno = EINVAL; 51 return (-1); 52 } 53 54 dfd = _open("/var/run/shm", O_RDONLY|O_DIRECTORY); 55 if (dfd >= 0) { 56 while (*path == '/') 57 ++path; 58 fd = _openat(dfd, path, flags, mode); 59 _close(dfd); 60 } else { 61 fd = _open(path, flags, mode); 62 } 63 64 if (fd != -1) { 65 if (_fstat(fd, &stab) != 0 || !S_ISREG(stab.st_mode)) { 66 _close(fd); 67 errno = EINVAL; 68 return (-1); 69 } 70 71 if (_fcntl(fd, F_SETFD, FD_CLOEXEC) != 0 || 72 _fcntl(fd, F_SETFL, (int)FPOSIXSHM) != 0) { 73 _close(fd); 74 return (-1); 75 } 76 } 77 return (fd); 78 } 79 80 int 81 shm_unlink(const char *path) 82 { 83 int res; 84 int dfd; 85 86 dfd = _open("/var/run/shm", O_RDONLY|O_DIRECTORY); 87 if (dfd >= 0) { 88 while (*path == '/') 89 ++path; 90 res = _unlinkat(dfd, path, 0); 91 _close(dfd); 92 } else { 93 res = _unlink(path); 94 } 95 return res; 96 } 97