1 /*
2 * This file and its contents are supplied under the terms of the
3 * Common Development and Distribution License ("CDDL"), version 1.0.
4 * You may only use this file in accordance with the terms of version
5 * 1.0 of the CDDL.
6 *
7 * A full copy of the text of the CDDL should have accompanied this
8 * source. A copy of the CDDL is also available via the Internet at
9 * http://www.illumos.org/license/CDDL.
10 */
11
12 /*
13 * Copyright 2020 Joyent, Inc.
14 */
15
16 /*
17 * Some simple testing of the read/writev() family: specifically we're checking
18 * IOV_MAX == 1024, and that a large-file compiled 32-bit binary can correctly
19 * access certain offsets.
20 */
21
22 #include <sys/uio.h>
23 #include <strings.h>
24 #include <limits.h>
25 #include <unistd.h>
26 #include <stdlib.h>
27 #include <stdio.h>
28 #include <errno.h>
29 #include <err.h>
30
31 #define ONE_GIG ((off_t)1024 * 1024 * 1024)
32
33 #define DATA_LEN (sizeof ("data"))
34
35 char path[] = "/var/tmp/writev_test.XXXXXX";
36
37 static void
cleanup(void)38 cleanup(void)
39 {
40 (void) unlink(path);
41 }
42
43 int
main(int argc,char * argv[])44 main(int argc, char *argv[])
45 {
46 char data[(IOV_MAX + 1) * DATA_LEN] = "";
47 struct iovec iov[IOV_MAX + 1];
48
49 if (IOV_MAX != 1024)
50 errx(EXIT_FAILURE, "IOV_MAX != 1024");
51
52 int fd = mkstemp(path);
53
54 if (fd == -1)
55 err(EXIT_FAILURE, "failed to create file");
56
57 (void) atexit(cleanup);
58
59 int ret = ftruncate(fd, ONE_GIG * 8);
60
61 if (ret != 0)
62 err(EXIT_FAILURE, "failed to truncate file");
63
64 for (int i = 0; i < IOV_MAX + 1; i++) {
65 (void) strcpy(data + i * DATA_LEN, "data");
66 iov[i].iov_base = data + i * 5;
67 iov[i].iov_len = DATA_LEN;
68 }
69
70 ssize_t written = writev(fd, iov, IOV_MAX + 1);
71
72 if (written != -1 || errno != EINVAL)
73 errx(EXIT_FAILURE, "writev(IOV_MAX + 1) didn't fail properly");
74
75 written = writev(fd, iov, IOV_MAX);
76
77 if (written == -1)
78 err(EXIT_FAILURE, "writev failed");
79
80 bzero(data, sizeof (data));
81
82 ssize_t read = preadv(fd, iov, IOV_MAX, 0);
83
84 if (read != DATA_LEN * IOV_MAX)
85 err(EXIT_FAILURE, "preadv failed");
86
87 for (int i = 0; i < IOV_MAX; i++) {
88 if (strcmp(data + i * DATA_LEN, "data") != 0)
89 errx(EXIT_FAILURE, "bad read at 0x%zx", i * DATA_LEN);
90 }
91
92 /*
93 * Now test various "interesting" offsets.
94 */
95
96 for (off_t off = 0; off < ONE_GIG * 8; off += ONE_GIG) {
97 if ((written = pwritev(fd, iov, 1, off)) != DATA_LEN)
98 err(EXIT_FAILURE, "pwritev(0x%" PRIx64 ") failed", off);
99 }
100
101 for (off_t off = 0; off < ONE_GIG * 8; off += ONE_GIG) {
102 if ((read = preadv(fd, iov, 1, off)) != DATA_LEN)
103 err(EXIT_FAILURE, "preadv(0x%" PRIx64 ") failed", off);
104 if (strcmp(data, "data") != 0)
105 errx(EXIT_FAILURE, "bad read at 0x%" PRIx64, off);
106 }
107
108 return (EXIT_SUCCESS);
109 }
110