ladybird/Tests/Kernel/TestEmptySharedInodeVMObject.cpp

/*
 * Copyright (c) 2022, Liav A. <liavalb@hotmail.co.il>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#include <LibTest/TestCase.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <sys/mman.h>

static u8* shared_ptr = nullptr;

static void shared_zero_length_inode_vmobject_sync_signal_handler(int)
{
    auto rc = msync(shared_ptr, 0x1000, MS_ASYNC);
    EXPECT(rc == 0);
    rc = munmap(shared_ptr, 0x1000);
    EXPECT(rc == 0);
    exit(0);
}

TEST_CASE(shared_zero_length_inode_vmobject_sync)
{
    {
        struct sigaction new_action {
            { shared_zero_length_inode_vmobject_sync_signal_handler }, 0, 0
        };
        int rc = sigaction(SIGBUS, &new_action, nullptr);
        VERIFY(rc == 0);
    }
    int fd = open("/tmp/shared_msync_test", O_RDWR | O_CREAT, 0644);
    VERIFY(fd >= 0);
    shared_ptr = (u8*)mmap(nullptr, 0x1000, PROT_READ | PROT_WRITE, MAP_FILE | MAP_SHARED, fd, 0);
    EXPECT(shared_ptr != MAP_FAILED);
    shared_ptr[0] = 0x1;
    VERIFY_NOT_REACHED();
}