hadoop-hdfs-project/hadoop-hdfs/src/contrib/libhdfs3/os/windows/sys/mman.c

/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * The MIT License (MIT)
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include <windows.h>
#include <errno.h>
#include <io.h>

#include "mman.h"

static int __map_mman_error(const DWORD err, const int deferr) {
    return err;
}

static DWORD __map_mmap_prot_page(const int prot) {
    DWORD protect = 0;

    if (prot == PROT_NONE)
        return protect;

    if ((prot & PROT_EXEC) != 0) {
        protect = ((prot & PROT_WRITE) != 0) ?
            PAGE_EXECUTE_READWRITE : PAGE_EXECUTE_READ;
    }
    else {
        protect = ((prot & PROT_WRITE) != 0) ?
            PAGE_READWRITE : PAGE_READONLY;
    }

    return protect;
}

static DWORD __map_mmap_prot_file(const int prot) {
    DWORD desiredAccess = 0;

    if (prot == PROT_NONE)
        return desiredAccess;

    if ((prot & PROT_READ) != 0)
        desiredAccess |= FILE_MAP_READ;
    if ((prot & PROT_WRITE) != 0)
        desiredAccess |= FILE_MAP_WRITE;
    if ((prot & PROT_EXEC) != 0)
        desiredAccess |= FILE_MAP_EXECUTE;

    return desiredAccess;
}

int posix_madvise(void *addr, size_t len, int advice) {
    // Ignore this function in Windows.
    // TODO: this can be implemented using PrefetchVirtualMemory.
    return 0;
}

void* mmap(void *addr,size_t len, int prot,
           int flags, int fildes, off_t off) {
    HANDLE fm, h;

    void * map = MAP_FAILED;

#ifdef _MSC_VER
#pragma warning(push)
#pragma warning(disable: 4293)
#endif

    const DWORD dwFileOffsetLow = (sizeof(off_t) <= sizeof(DWORD)) ?
        (DWORD)off : (DWORD)(off & 0xFFFFFFFFL);
    const DWORD dwFileOffsetHigh = (sizeof(off_t) <= sizeof(DWORD)) ?
        (DWORD)0 : (DWORD)((off >> 32) & 0xFFFFFFFFL);
    const DWORD protect = __map_mmap_prot_page(prot);
    const DWORD desiredAccess = __map_mmap_prot_file(prot);
    const off_t maxSize = off + (off_t)len;
    const DWORD dwMaxSizeLow = (sizeof(off_t) <= sizeof(DWORD)) ?
        (DWORD)maxSize : (DWORD)(maxSize & 0xFFFFFFFFL);
    const DWORD dwMaxSizeHigh = (sizeof(off_t) <= sizeof(DWORD)) ?
        (DWORD)0 : (DWORD)((maxSize >> 32) & 0xFFFFFFFFL);

#ifdef _MSC_VER
#pragma warning(pop)
#endif

    errno = 0;

    if (len == 0
        /* Unsupported flag combinations */
        || (flags & MAP_FIXED) != 0
        /* Usupported protection combinations */
        || prot == PROT_EXEC) {
        errno = EINVAL;
        return MAP_FAILED;
    }

    h = ((flags & MAP_ANONYMOUS) == 0) ?
        (HANDLE)_get_osfhandle(fildes) : INVALID_HANDLE_VALUE;

    if ((flags & MAP_ANONYMOUS) == 0 && h == INVALID_HANDLE_VALUE) {
        errno = EBADF;
        return MAP_FAILED;
    }

    fm =
        CreateFileMapping(h, NULL, protect, dwMaxSizeHigh, dwMaxSizeLow, NULL);

    if (fm == NULL) {
        errno = __map_mman_error(GetLastError(), EPERM);
        return MAP_FAILED;
    }
    map = MapViewOfFile(
        fm, desiredAccess,
        dwFileOffsetHigh, dwFileOffsetLow, len);

    CloseHandle(fm);

    if (map == NULL) {
        errno = __map_mman_error(GetLastError(), EPERM);
        return MAP_FAILED;
    }

    return map;
}

int munmap(void *addr, size_t len) {
    if (UnmapViewOfFile(addr))
        return 0;

    errno =  __map_mman_error(GetLastError(), EPERM);

    return -1;
}

int _mprotect(void *addr, size_t len, int prot) {
    DWORD newProtect = __map_mmap_prot_page(prot);
    DWORD oldProtect = 0;

    if (VirtualProtect(addr, len, newProtect, &oldProtect))
        return 0;

    errno =  __map_mman_error(GetLastError(), EPERM);

    return -1;
}

int msync(void *addr, size_t len, int flags) {
    if (FlushViewOfFile(addr, len))
        return 0;

    errno =  __map_mman_error(GetLastError(), EPERM);

    return -1;
}

int mlock(const void *addr, size_t len) {
    if (VirtualLock((LPVOID)addr, len))
        return 0;

    errno =  __map_mman_error(GetLastError(), EPERM);

    return -1;
}

int munlock(const void *addr, size_t len) {
    if (VirtualUnlock((LPVOID)addr, len))
        return 0;

    errno =  __map_mman_error(GetLastError(), EPERM);

    return -1;
}