/*
* Copyright (c), Microsoft Open Technologies, Inc.
* All rights reserved.
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*  - Redistributions of source code must retain the above copyright notice,
*    this list of conditions and the following disclaimer.
*  - Redistributions in binary form must reproduce the above copyright notice,
*    this list of conditions and the following disclaimer in the documentation
*    and/or other materials provided with the distribution.
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "Win32_Common.h"

namespace Globals
{
    size_t pageSize = 0;
}

/* This function is used to force the VEH on the entire size of the buffer length,
 * in the event that the buffer crosses the memory page boundaries */
void EnsureMemoryIsMapped(const void *buffer, size_t size) {
    // Use 'volatile' to make sure the compiler doesn't remove "c = *((char*) (p + offset));"
    volatile char c;
    char* p = (char*) buffer;
    char* pStart = p - ((size_t) p % Globals::pageSize);
    char* pEnd = p + size;
    if ((size_t) (pEnd - pStart) > Globals::pageSize) {
        size_t offset = 0;
        while (offset < size) {
            offset += Globals::pageSize;
            if (offset > size) {
                offset = size;
            }
            c = *((char*) (p + offset));
        }
    }
}

bool IsWindowsVersionAtLeast(WORD wMajorVersion, WORD wMinorVersion, WORD wServicePackMajor) {
    OSVERSIONINFOEXW osvi = {sizeof(osvi), 0, 0, 0, 0, {0}, 0, 0};
    DWORDLONG const dwlConditionMask = VerSetConditionMask(
        VerSetConditionMask(
        VerSetConditionMask(
        0, VER_MAJORVERSION, VER_GREATER_EQUAL),
        VER_MINORVERSION, VER_GREATER_EQUAL),
        VER_SERVICEPACKMAJOR, VER_GREATER_EQUAL);

    osvi.dwMajorVersion = wMajorVersion;
    osvi.dwMinorVersion = wMinorVersion;
    osvi.wServicePackMajor = wServicePackMajor;

    return VerifyVersionInfoW(&osvi, VER_MAJORVERSION | VER_MINORVERSION | VER_SERVICEPACKMAJOR, dwlConditionMask) != FALSE;
}
