2 * Copyright (c) 2007 Dag-Erling Coïdan Smørgrav
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer
10 * in this position and unchanged.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
42 flopen(const char *path, int flags, ...)
44 int fd, operation, serrno, trunc;
54 if (flags & O_CREAT) {
58 mode = (mode_t)va_arg(ap, int); /* mode_t promoted to int */
62 memset(&lock, 0, sizeof lock);
63 lock.l_type = ((flags & O_ACCMODE) == O_RDONLY) ? F_RDLCK : F_WRLCK;
64 lock.l_whence = SEEK_SET;
65 operation = (flags & O_NONBLOCK) ? F_SETLK : F_SETLKW;
67 trunc = (flags & O_TRUNC);
71 if ((fd = open(path, flags, mode)) == -1)
72 /* non-existent or no access */
74 if (fcntl(fd, operation, &lock) == -1) {
75 /* unsupported or interrupted */
81 if (stat(path, &sb) == -1) {
82 /* disappeared from under our feet */
86 if (fstat(fd, &fsb) == -1) {
87 /* can't happen [tm] */
93 if (sb.st_dev != fsb.st_dev ||
94 sb.st_ino != fsb.st_ino) {
95 /* changed under our feet */
99 if (trunc && ftruncate(fd, 0) != 0) {
100 /* can't happen [tm] */