Colony » Colony Scout

/*

 * $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: src/tools/regression/file/dup/dup.c,v 1.2.2.1.2.1 2008/11/25 02:59:29 kensmith Exp $

 */

/* Modified for Prex by Kohsuke Ohtani */

/*

 * 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.

 */

#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 argc, char *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);

#if 0

        /* 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);

#endif

        /*

         * 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);

#if 0

        /* 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);

#endif

        /* Does fcntl(F_DUPFD) work? */

        if ((fd2 = fcntl(fd1, F_DUPFD, 0)) < 0)

                err(1, "fcntl(F_DUPFD)");

        printf("ok %d - fcntl(F_DUPFD) works\n", ++test);

#if 0

        /* 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);

#endif

        ++test;

        if (getrlimit(RLIMIT_NOFILE, &rlp) < 0)

                err(1, "getrlimit");

        if ((fd2 = dup2(fd1, (int)(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);

        return (0);

}