/*
 * This file and its contents are supplied under the terms of the
 * Common Development and Distribution License ("CDDL"), version 1.0.
 * You may only use this file in accordance with the terms of version
 * 1.0 of the CDDL.
 *
 * A full copy of the text of the CDDL should have accompanied this
 * source.  A copy of the CDDL is also available via the Internet at
 * http://www.illumos.org/license/CDDL.
 */

/*
 * Copyright 2016 Joyent, Inc.
 */

/*
 * Basic tests for posix_memalign(3C). Note that we test ENOMEM failure by
 * relying on the implementation of the current libc malloc. Specifically we go
 * through and add a mapping so we can't expand the heap and then use it up. If
 * the memory allocator is ever changed, this test will start failing, at which
 * point, it may not be worth the cost of keeping it around.
 */

#include <stdlib.h>
#include <errno.h>
#include <libproc.h>
#include <sys/sysmacros.h>
#include <sys/mman.h>
#include <sys/debug.h>

int
main(void)
{
        pstatus_t status;
        /*
         * We use a non-NULL value, so we can verify that failure does not
         * change the value of 'buf'
         */
        void *sentinel = (void *)0xbad00000;
        void *buf = sentinel;
        int err = 0;

        /*
         * Alignment must be sizeof (void *) (word) aligned.
         */
        err = posix_memalign(&buf, sizeof (void *) - 1, 16);
        VERIFY3S(err, ==, EINVAL);
        VERIFY3P(buf, ==, sentinel);

        err = posix_memalign(&buf, sizeof (void *) + 1, 16);
        VERIFY3S(err, ==, EINVAL);
        VERIFY3P(buf, ==, sentinel);

        err = posix_memalign(&buf, 23, 16);
        VERIFY3S(err, ==, EINVAL);
        VERIFY3P(buf, ==, sentinel);

        err = posix_memalign(&buf, sizeof (void *), 16);
        VERIFY3S(err, ==, 0);
        VERIFY3B(IS_P2ALIGNED(buf, sizeof (void *)), ==, B_TRUE);
        VERIFY3P(buf, !=, sentinel);
        VERIFY3P(buf, !=, NULL);
        free(buf);
        buf = sentinel;

        /*
         * Cause ENOMEM
         */
        VERIFY0(proc_get_status(getpid(), &status));
        VERIFY3P(mmap((caddr_t)P2ROUNDUP(status.pr_brkbase +
            status.pr_brksize, 0x1000), 0x1000,
            PROT_READ, MAP_ANON | MAP_FIXED | MAP_PRIVATE, -1, 0),
            !=, (void *)-1);

        for (;;) {
                if (malloc(16) == NULL)
                        break;
        }


        for (;;) {
                if (posix_memalign(&buf, sizeof (void *), 16) == ENOMEM)
                        break;
        }

        buf = sentinel;
        err = posix_memalign(&buf, sizeof (void *), 16);
        VERIFY3S(err, ==, ENOMEM);
        VERIFY3P(buf, ==, sentinel);

        return (0);
}