2 * $OpenBSD: dup2test.c,v 1.3 2003/07/31 21:48:08 deraadt Exp $
3 * $OpenBSD: dup2_self.c,v 1.3 2003/07/31 21:48:08 deraadt Exp $
4 * $OpenBSD: fcntl_dup.c,v 1.2 2003/07/31 21:48:08 deraadt Exp $
6 * Written by Artur Grabowski <art@openbsd.org> 2002 Public Domain.
12 * Test #1: check if dup(2) works.
13 * Test #2: check if dup2(2) works.
14 * Test #3: check if dup2(2) returned a fd we asked for.
15 * Test #4: check if dup2(2) cleared close-on-exec flag for duped fd.
16 * Test #5: check if dup2(2) allows to dup fd to itself.
17 * Test #6: check if dup2(2) returned a fd we asked for.
18 * Test #7: check if dup2(2) did not clear close-on-exec flag for duped fd.
19 * Test #8: check if fcntl(F_DUPFD) works.
20 * Test #9: check if fcntl(F_DUPFD) cleared close-on-exec flag for duped fd.
21 * Test #10: check if dup2() to a fd > current maximum number of open files
23 * Test #11: check if fcntl(F_DUP2FD) works.
24 * Test #12: check if fcntl(F_DUP2FD) returned a fd we asked for.
25 * Test #13: check if fcntl(F_DUP2FD) cleared close-on-exec flag for duped fd.
26 * Test #14: check if fcntl(F_DUP2FD) allows to dup fd to itself.
27 * Test #15: check if fcntl(F_DUP2FD) returned a fd we asked for.
28 * Test #16: check if fcntl(F_DUP2FD) did not clear close-on-exec flag for
30 * Test #17: check if fcntl(F_DUP2FD) to a fd > current maximum number of open
34 #include <sys/types.h>
36 #include <sys/resource.h>
44 static int getafile(void);
51 char temp[] = "/tmp/dup2XXXXXXXXX";
52 if ((fd = mkstemp(temp)) < 0)
55 if (ftruncate(fd, 1024) != 0)
61 main(int __unused argc, char __unused *argv[])
64 int orgfd, fd1, fd2, test = 0;
70 /* If dup(2) ever work? */
71 if ((fd1 = dup(orgfd)) < 0)
73 printf("ok %d - dup(2) works\n", ++test);
75 /* Set close-on-exec */
76 if (fcntl(fd1, F_SETFD, 1) != 0)
77 err(1, "fcntl(F_SETFD)");
79 /* If dup2(2) ever work? */
80 if ((fd2 = dup2(fd1, fd1 + 1)) < 0)
82 printf("ok %d - dup2(2) works\n", ++test);
84 /* Do we get the right fd? */
87 printf("no ok %d - dup2(2) didn't give us the right fd\n",
90 printf("ok %d - dup2(2) returned a correct fd\n", test);
92 /* Was close-on-exec cleared? */
94 if (fcntl(fd2, F_GETFD) != 0)
95 printf("not ok %d - dup2(2) didn't clear close-on-exec\n",
98 printf("ok %d - dup2(2) cleared close-on-exec\n", test);
103 * We're testing a small tweak in dup2 semantics.
104 * Normally dup and dup2 will clear the close-on-exec
105 * flag on the new fd (which appears to be an implementation
106 * mistake from start and not some planned behavior).
107 * In todays implementations of dup and dup2 we have to make
108 * an effort to really clear that flag. But all tested
109 * implementations of dup2 have another tweak. If we
110 * dup2(old, new) when old == new, the syscall short-circuits
111 * and returns early (because there is no need to do all the
112 * work (and there is a risk for serious mistakes)).
113 * So although the docs say that dup2 should "take 'old',
114 * close 'new' perform a dup(2) of 'old' into 'new'"
115 * the docs are not really followed because close-on-exec
116 * is not cleared on 'new'.
118 * Since everyone has this bug, we pretend that this is
119 * the way it is supposed to be and test here that it really
122 * This is a fine example on where two separate implementation
123 * fuckups take out each other and make the end-result the way
124 * it was meant to be.
126 if ((fd2 = dup2(fd1, fd1)) < 0)
128 printf("ok %d - dup2(2) to itself works\n", ++test);
130 /* Do we get the right fd? */
133 printf("not ok %d - dup2(2) didn't give us the right fd\n",
136 printf("ok %d - dup2(2) to itself returned a correct fd\n",
139 /* Was close-on-exec cleared? */
141 if (fcntl(fd2, F_GETFD) == 0)
142 printf("not ok %d - dup2(2) cleared close-on-exec\n", test);
144 printf("ok %d - dup2(2) didn't clear close-on-exec\n", test);
146 /* Does fcntl(F_DUPFD) work? */
147 if ((fd2 = fcntl(fd1, F_DUPFD)) < 0)
148 err(1, "fcntl(F_DUPFD)");
149 printf("ok %d - fcntl(F_DUPFD) works\n", ++test);
151 /* Was close-on-exec cleared? */
153 if (fcntl(fd2, F_GETFD) != 0)
155 "not ok %d - fcntl(F_DUPFD) didn't clear close-on-exec\n",
158 printf("ok %d - fcntl(F_DUPFD) cleared close-on-exec\n", test);
161 if (getrlimit(RLIMIT_NOFILE, &rlp) < 0)
163 if ((fd2 = dup2(fd1, rlp.rlim_cur + 1)) >= 0)
164 printf("not ok %d - dup2(2) bypassed NOFILE limit\n", test);
166 printf("ok %d - dup2(2) didn't bypass NOFILE limit\n", test);
168 /* If fcntl(F_DUP2FD) ever work? */
169 if ((fd2 = fcntl(fd1, F_DUP2FD, fd1 + 1)) < 0)
170 err(1, "fcntl(F_DUP2FD)");
171 printf("ok %d - fcntl(F_DUP2FD) works\n", ++test);
173 /* Do we get the right fd? */
177 "no ok %d - fcntl(F_DUP2FD) didn't give us the right fd\n",
180 printf("ok %d - fcntl(F_DUP2FD) returned a correct fd\n",
183 /* Was close-on-exec cleared? */
185 if (fcntl(fd2, F_GETFD) != 0)
187 "not ok %d - fcntl(F_DUP2FD) didn't clear close-on-exec\n",
190 printf("ok %d - fcntl(F_DUP2FD) cleared close-on-exec\n",
194 if ((fd2 = fcntl(fd1, F_DUP2FD, fd1)) < 0)
195 err(1, "fcntl(F_DUP2FD)");
196 printf("ok %d - fcntl(F_DUP2FD) to itself works\n", ++test);
198 /* Do we get the right fd? */
202 "not ok %d - fcntl(F_DUP2FD) didn't give us the right fd\n",
206 "ok %d - fcntl(F_DUP2FD) to itself returned a correct fd\n",
209 /* Was close-on-exec cleared? */
211 if (fcntl(fd2, F_GETFD) == 0)
212 printf("not ok %d - fcntl(F_DUP2FD) cleared close-on-exec\n",
215 printf("ok %d - fcntl(F_DUP2FD) didn't clear close-on-exec\n",
219 if (getrlimit(RLIMIT_NOFILE, &rlp) < 0)
221 if ((fd2 = fcntl(fd1, F_DUP2FD, rlp.rlim_cur + 1)) >= 0)
222 printf("not ok %d - fcntl(F_DUP2FD) bypassed NOFILE limit\n",
225 printf("ok %d - fcntl(F_DUP2FD) didn't bypass NOFILE limit\n",