/*      $NetBSD: t_renamerace.c,v 1.15 2020/06/26 07:50:12 jruoho Exp $ */

/*
 * Modified for rump and atf from a program supplied
 * by Nicolas Joly in PR kern/40948
 */

#include <sys/types.h>
#include <sys/mount.h>
#include <sys/utsname.h>

#include <atf-c.h>
#include <errno.h>
#include <fcntl.h>
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include <rump/rump.h>
#include <rump/rump_syscalls.h>

#include <fs/tmpfs/tmpfs_args.h>

#include "h_macros.h"

ATF_TC(renamerace2);
ATF_TC_HEAD(renamerace2, tc)
{
        atf_tc_set_md_var(tc, "descr", "rename(2) lock order inversion");
        atf_tc_set_md_var(tc, "timeout", "6");
}

static volatile int quittingtime = 0;
static pid_t wrkpid;

static void *
r2w1(void *arg)
{
        int fd;

        rump_pub_lwproc_newlwp(wrkpid);

        fd = rump_sys_open("/file", O_CREAT | O_RDWR, 0777);
        if (fd == -1)
                atf_tc_fail_errno("creat");
        rump_sys_close(fd);

        while (!quittingtime) {
                if (rump_sys_rename("/file", "/dir/file") == -1)
                        atf_tc_fail_errno("rename 1");
                if (rump_sys_rename("/dir/file", "/file") == -1)
                        atf_tc_fail_errno("rename 2");
        }

        return NULL;
}

static void *
r2w2(void *arg)
{
        int fd;

        rump_pub_lwproc_newlwp(wrkpid);

        while (!quittingtime) {
                fd = rump_sys_open("/dir/file1", O_RDWR);
                if (fd != -1)
                        rump_sys_close(fd);
        }

        return NULL;
}

ATF_TC_BODY(renamerace2, tc)
{
        struct tmpfs_args args;
        pthread_t pt[2];

        /*
         * Force SMP regardless of how many host CPUs there are.
         * Deadlock is highly unlikely to trigger otherwise.
         */
        setenv("RUMP_NCPU", "2", 1);

        rump_init();
        memset(&args, 0, sizeof(args));
        args.ta_version = TMPFS_ARGS_VERSION;
        args.ta_root_mode = 0777;
        if (rump_sys_mount(MOUNT_TMPFS, "/", 0, &args, sizeof(args)) == -1)
                atf_tc_fail_errno("could not mount tmpfs");

        if (rump_sys_mkdir("/dir", 0777) == -1)
                atf_tc_fail_errno("cannot create directory");

        RZ(rump_pub_lwproc_rfork(RUMP_RFCFDG));
        RL(wrkpid = rump_sys_getpid());
        pthread_create(&pt[0], NULL, r2w1, NULL);
        pthread_create(&pt[1], NULL, r2w2, NULL);

        /* usually triggers in <<1s for me */
        sleep(4);
        quittingtime = 1;

        pthread_join(pt[0], NULL);
        pthread_join(pt[1], NULL);
}

ATF_TP_ADD_TCS(tp)
{
        ATF_TP_ADD_TC(tp, renamerace2);

        return atf_no_error();
}