xref: /illumos-gate/usr/src/test/libc-tests/tests/printf-15294.c (revision ddb365bfc9e868ad24ccdcb0dc91af18b10df082)
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 2022 Oxide Computer Company
14  * Copyright 2022 OmniOS Community Edition (OmniOSce) Association.
15  */
16 
17 /*
18  * Regression test for illumos #15294. A change in isatty(3C) caused printf(3C)
19  * to start setting errno on a successful call if the output is not a TTY.
20  */
21 
22 #include <err.h>
23 #include <errno.h>
24 #include <fcntl.h>
25 #include <stdarg.h>
26 #include <stdbool.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <strings.h>
31 #include <unistd.h>
32 #include <sys/debug.h>
33 #include <sys/types.h>
34 
35 #include "common/openpty.c"
36 
37 static int failures;
38 
39 static void
40 fail(const char *fmt, ...)
41 {
42 	va_list va;
43 
44 	va_start(va, fmt);
45 	(void) vfprintf(stderr, fmt, va);
46 	va_end(va);
47 
48 	failures++;
49 }
50 
51 static void
52 test_file(FILE *fp, char *tag, int e_n, int e_err)
53 {
54 	int n, err;
55 
56 	errno = 0;
57 	n = fprintf(fp, "%s", tag);
58 	err = errno;
59 
60 	if (n != e_n)
61 		fail("%s return value was %d, expected %d\n", tag, n, e_n);
62 	if (err != e_err)
63 		fail("%s errno value was %d, expected %d\n", tag, errno, e_err);
64 }
65 
66 int
67 main(void)
68 {
69 	int mfd, sfd;
70 	FILE *fp, *sfp;
71 
72 	if (!openpty(&mfd, &sfd))
73 		errx(EXIT_FAILURE, "failed to open a pty");
74 	if (isatty(sfd) != 1)
75 		errx(EXIT_FAILURE, "subsidiary PTY fd somehow isn't a TTY!");
76 
77 	fp = tmpfile();
78 	if (fp == NULL)
79 		errx(EXIT_FAILURE, "could not create temporary file");
80 
81 	if ((sfp = fdopen(sfd, "w")) == NULL)
82 		errx(EXIT_FAILURE, "could not fdopen subsidiary PTY fd");
83 
84 	test_file(fp, "test non-PTY", sizeof ("test non-PTY") - 1, 0);
85 	test_file(sfp, "test PTY", sizeof ("test PTY") - 1, 0);
86 
87 	VERIFY0(fclose(fp));
88 	VERIFY0(fclose(sfp));
89 	VERIFY0(close(mfd));
90 
91 	return (failures);
92 }
93