1 /* SPDX-License-Identifier: MIT */
2 /*
3 * Description: test io_uring linkat handling
4 */
5 #include <fcntl.h>
6 #include <stdio.h>
7 #include <string.h>
8 #include <sys/stat.h>
9 #include <sys/types.h>
10 #include <unistd.h>
11
12 #include "liburing.h"
13
14
do_linkat(struct io_uring * ring,const char * oldname,const char * newname)15 static int do_linkat(struct io_uring *ring, const char *oldname, const char *newname)
16 {
17 int ret;
18 struct io_uring_sqe *sqe;
19 struct io_uring_cqe *cqe;
20
21 sqe = io_uring_get_sqe(ring);
22 if (!sqe) {
23 fprintf(stderr, "sqe get failed\n");
24 goto err;
25 }
26 io_uring_prep_linkat(sqe, AT_FDCWD, oldname, AT_FDCWD, newname, 0);
27
28 ret = io_uring_submit(ring);
29 if (ret != 1) {
30 fprintf(stderr, "submit failed: %d\n", ret);
31 goto err;
32 }
33
34 ret = io_uring_wait_cqes(ring, &cqe, 1, 0, 0);
35 if (ret) {
36 fprintf(stderr, "wait_cqe failed: %d\n", ret);
37 goto err;
38 }
39 ret = cqe->res;
40 io_uring_cqe_seen(ring, cqe);
41 return ret;
42 err:
43 return 1;
44 }
45
files_linked_ok(const char * fn1,const char * fn2)46 int files_linked_ok(const char* fn1, const char *fn2)
47 {
48 struct stat s1, s2;
49
50 if (stat(fn1, &s1)) {
51 fprintf(stderr, "stat(%s): %s\n", fn1, strerror(errno));
52 return 0;
53 }
54 if (stat(fn2, &s2)) {
55 fprintf(stderr, "stat(%s): %s\n", fn2, strerror(errno));
56 return 0;
57 }
58 if (s1.st_dev != s2.st_dev || s1.st_ino != s2.st_ino) {
59 fprintf(stderr, "linked files have different device / inode numbers\n");
60 return 0;
61 }
62 if (s1.st_nlink != 2 || s2.st_nlink != 2) {
63 fprintf(stderr, "linked files have unexpected links count\n");
64 return 0;
65 }
66 return 1;
67 }
68
main(int argc,char * argv[])69 int main(int argc, char *argv[])
70 {
71 static const char target[] = "io_uring-linkat-test-target";
72 static const char linkname[] = "io_uring-linkat-test-link";
73 int ret;
74 struct io_uring ring;
75
76 ret = io_uring_queue_init(8, &ring, 0);
77 if (ret) {
78 fprintf(stderr, "queue init failed: %d\n", ret);
79 return ret;
80 }
81
82 ret = open(target, O_CREAT | O_RDWR | O_EXCL, 0600);
83 if (ret < 0) {
84 perror("open");
85 goto err;
86 }
87 if (write(ret, "linktest", 8) != 8) {
88 close(ret);
89 goto err1;
90 }
91 close(ret);
92
93 ret = do_linkat(&ring, target, linkname);
94 if (ret < 0) {
95 if (ret == -EBADF || ret == -EINVAL) {
96 fprintf(stdout, "linkat not supported, skipping\n");
97 goto out;
98 }
99 fprintf(stderr, "linkat: %s\n", strerror(-ret));
100 goto err1;
101 } else if (ret) {
102 goto err1;
103 }
104
105 if (!files_linked_ok(linkname, target))
106 goto err2;
107
108 ret = do_linkat(&ring, target, linkname);
109 if (ret != -EEXIST) {
110 fprintf(stderr, "test_linkat linkname already exists failed: %d\n", ret);
111 goto err2;
112 }
113
114 ret = do_linkat(&ring, target, "surely/this/does/not/exist");
115 if (ret != -ENOENT) {
116 fprintf(stderr, "test_linkat no parent failed: %d\n", ret);
117 goto err2;
118 }
119
120 out:
121 unlinkat(AT_FDCWD, linkname, 0);
122 unlinkat(AT_FDCWD, target, 0);
123 io_uring_queue_exit(&ring);
124 return 0;
125 err2:
126 unlinkat(AT_FDCWD, linkname, 0);
127 err1:
128 unlinkat(AT_FDCWD, target, 0);
129 err:
130 io_uring_queue_exit(&ring);
131 return 1;
132 }
133
134