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/*
* $OpenBSD: dup2test.c,v 1.3 2003/07/31 21:48:08 deraadt Exp $
* $OpenBSD: dup2_self.c,v 1.3 2003/07/31 21:48:08 deraadt Exp $
* $OpenBSD: fcntl_dup.c,v 1.2 2003/07/31 21:48:08 deraadt Exp $
*
* Written by Artur Grabowski <art@openbsd.org> 2002 Public Domain.
*
* $FreeBSD$
*/
/*
* Test #1: check if dup(2) works.
* Test #2: check if dup2(2) works.
* Test #3: check if dup2(2) returned a fd we asked for.
* Test #4: check if dup2(2) cleared close-on-exec flag for duped fd.
* Test #5: check if dup2(2) allows to dup fd to itself.
* Test #6: check if dup2(2) returned a fd we asked for.
* Test #7: check if dup2(2) did not clear close-on-exec flag for duped fd.
* Test #8: check if fcntl(F_DUPFD) works.
* Test #9: check if fcntl(F_DUPFD) cleared close-on-exec flag for duped fd.
* Test #10: check if dup2() to a fd > current maximum number of open files
* limit work.
* Test #11: check if fcntl(F_DUP2FD) works.
* Test #12: check if fcntl(F_DUP2FD) returned a fd we asked for.
* Test #13: check if fcntl(F_DUP2FD) cleared close-on-exec flag for duped fd.
* Test #14: check if fcntl(F_DUP2FD) allows to dup fd to itself.
* Test #15: check if fcntl(F_DUP2FD) returned a fd we asked for.
* Test #16: check if fcntl(F_DUP2FD) did not clear close-on-exec flag for
* duped fd.
* Test #17: check if fcntl(F_DUP2FD) to a fd > current maximum number of open
* files limit work.
*/
#include <sys/types.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <err.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
static int getafile(void);
static int
getafile(void)
{
int fd;
char temp[] = "/tmp/dup2XXXXXXXXX";
if ((fd = mkstemp(temp)) < 0)
err(1, "mkstemp");
remove(temp);
if (ftruncate(fd, 1024) != 0)
err(1, "ftruncate");
return (fd);
}
int
main(int __unused argc, char __unused *argv[])
{
struct rlimit rlp;
int orgfd, fd1, fd2, test = 0;
orgfd = getafile();
printf("1..17\n");
/* If dup(2) ever work? */
if ((fd1 = dup(orgfd)) < 0)
err(1, "dup");
printf("ok %d - dup(2) works\n", ++test);
/* Set close-on-exec */
if (fcntl(fd1, F_SETFD, 1) != 0)
err(1, "fcntl(F_SETFD)");
/* If dup2(2) ever work? */
if ((fd2 = dup2(fd1, fd1 + 1)) < 0)
err(1, "dup2");
printf("ok %d - dup2(2) works\n", ++test);
/* Do we get the right fd? */
++test;
if (fd2 != fd1 + 1)
printf("no ok %d - dup2(2) didn't give us the right fd\n",
test);
else
printf("ok %d - dup2(2) returned a correct fd\n", test);
/* Was close-on-exec cleared? */
++test;
if (fcntl(fd2, F_GETFD) != 0)
printf("not ok %d - dup2(2) didn't clear close-on-exec\n",
test);
else
printf("ok %d - dup2(2) cleared close-on-exec\n", test);
/*
* Dup to itself.
*
* We're testing a small tweak in dup2 semantics.
* Normally dup and dup2 will clear the close-on-exec
* flag on the new fd (which appears to be an implementation
* mistake from start and not some planned behavior).
* In todays implementations of dup and dup2 we have to make
* an effort to really clear that flag. But all tested
* implementations of dup2 have another tweak. If we
* dup2(old, new) when old == new, the syscall short-circuits
* and returns early (because there is no need to do all the
* work (and there is a risk for serious mistakes)).
* So although the docs say that dup2 should "take 'old',
* close 'new' perform a dup(2) of 'old' into 'new'"
* the docs are not really followed because close-on-exec
* is not cleared on 'new'.
*
* Since everyone has this bug, we pretend that this is
* the way it is supposed to be and test here that it really
* works that way.
*
* This is a fine example on where two separate implementation
* fuckups take out each other and make the end-result the way
* it was meant to be.
*/
if ((fd2 = dup2(fd1, fd1)) < 0)
err(1, "dup2");
printf("ok %d - dup2(2) to itself works\n", ++test);
/* Do we get the right fd? */
++test;
if (fd2 != fd1)
printf("not ok %d - dup2(2) didn't give us the right fd\n",
test);
else
printf("ok %d - dup2(2) to itself returned a correct fd\n",
test);
/* Was close-on-exec cleared? */
++test;
if (fcntl(fd2, F_GETFD) == 0)
printf("not ok %d - dup2(2) cleared close-on-exec\n", test);
else
printf("ok %d - dup2(2) didn't clear close-on-exec\n", test);
/* Does fcntl(F_DUPFD) work? */
if ((fd2 = fcntl(fd1, F_DUPFD)) < 0)
err(1, "fcntl(F_DUPFD)");
printf("ok %d - fcntl(F_DUPFD) works\n", ++test);
/* Was close-on-exec cleared? */
++test;
if (fcntl(fd2, F_GETFD) != 0)
printf(
"not ok %d - fcntl(F_DUPFD) didn't clear close-on-exec\n",
test);
else
printf("ok %d - fcntl(F_DUPFD) cleared close-on-exec\n", test);
++test;
if (getrlimit(RLIMIT_NOFILE, &rlp) < 0)
err(1, "getrlimit");
if ((fd2 = dup2(fd1, rlp.rlim_cur + 1)) >= 0)
printf("not ok %d - dup2(2) bypassed NOFILE limit\n", test);
else
printf("ok %d - dup2(2) didn't bypass NOFILE limit\n", test);
/* If fcntl(F_DUP2FD) ever work? */
if ((fd2 = fcntl(fd1, F_DUP2FD, fd1 + 1)) < 0)
err(1, "fcntl(F_DUP2FD)");
printf("ok %d - fcntl(F_DUP2FD) works\n", ++test);
/* Do we get the right fd? */
++test;
if (fd2 != fd1 + 1)
printf(
"no ok %d - fcntl(F_DUP2FD) didn't give us the right fd\n",
test);
else
printf("ok %d - fcntl(F_DUP2FD) returned a correct fd\n",
test);
/* Was close-on-exec cleared? */
++test;
if (fcntl(fd2, F_GETFD) != 0)
printf(
"not ok %d - fcntl(F_DUP2FD) didn't clear close-on-exec\n",
test);
else
printf("ok %d - fcntl(F_DUP2FD) cleared close-on-exec\n",
test);
/* Dup to itself */
if ((fd2 = fcntl(fd1, F_DUP2FD, fd1)) < 0)
err(1, "fcntl(F_DUP2FD)");
printf("ok %d - fcntl(F_DUP2FD) to itself works\n", ++test);
/* Do we get the right fd? */
++test;
if (fd2 != fd1)
printf(
"not ok %d - fcntl(F_DUP2FD) didn't give us the right fd\n",
test);
else
printf(
"ok %d - fcntl(F_DUP2FD) to itself returned a correct fd\n",
test);
/* Was close-on-exec cleared? */
++test;
if (fcntl(fd2, F_GETFD) == 0)
printf("not ok %d - fcntl(F_DUP2FD) cleared close-on-exec\n",
test);
else
printf("ok %d - fcntl(F_DUP2FD) didn't clear close-on-exec\n",
test);
++test;
if (getrlimit(RLIMIT_NOFILE, &rlp) < 0)
err(1, "getrlimit");
if ((fd2 = fcntl(fd1, F_DUP2FD, rlp.rlim_cur + 1)) >= 0)
printf("not ok %d - fcntl(F_DUP2FD) bypassed NOFILE limit\n",
test);
else
printf("ok %d - fcntl(F_DUP2FD) didn't bypass NOFILE limit\n",
test);
return (0);
}
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