libfuse: fuse-3.17.4/example/passthrough_helpers.h Source File

libfuse

passthrough_helpers.h
1/*
2 * FUSE: Filesystem in Userspace
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23 * SUCH DAMAGE
24 */
25
26/*
27 * Creates files on the underlying file system in response to a FUSE_MKNOD
28 * operation
29 */
30static int mknod_wrapper(int dirfd, const char *path, const char *link,
31 int mode, dev_t rdev)
32{
33 int res;
34
35 if (S_ISREG(mode)) {
36 res = openat(dirfd, path, O_CREAT | O_EXCL | O_WRONLY, mode);
37 if (res >= 0)
38 res = close(res);
39 } else if (S_ISDIR(mode)) {
40 res = mkdirat(dirfd, path, mode);
41 } else if (S_ISLNK(mode) && link != NULL) {
42 res = symlinkat(link, dirfd, path);
43 } else if (S_ISFIFO(mode)) {
44 res = mkfifoat(dirfd, path, mode);
45#ifdef __FreeBSD__
46 } else if (S_ISSOCK(mode)) {
47 struct sockaddr_un su;
48 int fd;
49
50 if (strlen(path) >= sizeof(su.sun_path)) {
51 errno = ENAMETOOLONG;
52 return -1;
53 }
54 fd = socket(AF_UNIX, SOCK_STREAM, 0);
55 if (fd >= 0) {
56 /*
57 * We must bind the socket to the underlying file
58 * system to create the socket file, even though
59 * we'll never listen on this socket.
60 */
61 su.sun_family = AF_UNIX;
62 strncpy(su.sun_path, path, sizeof(su.sun_path));
63 res = bindat(dirfd, fd, (struct sockaddr*)&su,
64 sizeof(su));
65 if (res == 0)
66 close(fd);
67 } else {
68 res = -1;
69 }
70#endif
71 } else {
72 res = mknodat(dirfd, path, mode, rdev);
73 }
74
75 return res;
76}