1 /* $OpenBSD: pwritev.c,v 1.5 2011/11/06 15:00:34 guenther Exp $ */
2 /*
3 * Written by Artur Grabowski <art@openbsd.org> 2002 Public Domain.
4 */
5 #include <sys/types.h>
6 #include <sys/uio.h>
7 #include <err.h>
8 #include <errno.h>
9 #include <fcntl.h>
10 #include <limits.h>
11 #include <stdio.h>
12 #include <stdlib.h>
13 #include <string.h>
14 #include <unistd.h>
15
16 int
main(int argc,char * argv[])17 main(int argc, char *argv[])
18 {
19 char temp[] = "/tmp/pwritevXXXXXXXXX";
20 char magic[10] = "0123456789";
21 const char zeroes[10] = "0000000000";
22 char buf[10];
23 struct iovec iov[2];
24 char c;
25 int fd, ret;
26
27 if ((fd = mkstemp(temp)) < 0)
28 err(1, "mkstemp");
29 remove(temp);
30
31 if (write(fd, zeroes, sizeof(zeroes)) != sizeof(zeroes))
32 err(1, "write");
33
34 if (lseek(fd, 5, SEEK_SET) != 5)
35 err(1, "lseek");
36
37 iov[0].iov_base = &magic[8];
38 iov[0].iov_len = 2;
39 iov[1].iov_base = &magic[7];
40 iov[1].iov_len = 2;
41
42 if (pwritev(fd, iov, 2, 4) != 4)
43 err(1, "pwritev");
44
45 if (read(fd, &c, 1) != 1)
46 err(1, "read");
47
48 if (c != '9')
49 errx(1, "read %c != %c", c, '9');
50
51 c = '5';
52 if (write(fd, &c, 1) != 1)
53 err(1, "write");
54
55 if (pread(fd, buf, 10, 0) != 10)
56 err(1, "pread");
57
58 iov[1].iov_base = &magic[1];
59 iov[1].iov_len = 2;
60 if ((ret = pwritev(fd, iov, 2, -1)) != -1)
61 errx(1, "pwritev with negative offset succeeded,\
62 returning %d", ret);
63 if (errno != EINVAL)
64 err(1, "pwritev with negative offset");
65
66 if ((ret = pwritev(fd, iov, 2, LLONG_MAX)) != -1)
67 errx(1, "pwritev with wrapping offset succeeded,\
68 returning %d", ret);
69 if (errno != EFBIG && errno != EINVAL)
70 err(1, "pwritev with wrapping offset");
71
72 if (memcmp(buf, "0000895800", 10) != 0)
73 errx(1, "data mismatch: %s != %s", buf, "0000895800");
74
75 /* pwrite should be unaffected by O_APPEND */
76 if (fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_APPEND))
77 err(1, "fcntl");
78 if (pwritev(fd, iov, 2, 2) != 4)
79 err(1, "pwritev");
80 if (pread(fd, buf, 10, 0) != 10)
81 err(1, "pread");
82 if (memcmp(buf, "0089125800", 10) != 0)
83 errx(1, "data mismatch: %s != %s", buf, "0089125800");
84
85 close(fd);
86
87 /* also, verify that pwritev fails on ttys */
88 fd = open("/dev/tty", O_RDWR);
89 if (fd < 0)
90 printf("skipping tty test\n");
91 else if ((ret = pwritev(fd, iov, 2, 7)) != -1)
92 errx(1, "pwritev succeeded on tty, returning %d", ret);
93 else if (errno != ESPIPE)
94 err(1, "pwritev");
95
96 return 0;
97 }
98