SafeNativeMethods.cs source code in C# .NET

Source code for the .NET framework in C#

                        
Code:

                         / FX-1434 / FX-1434 / 1.0 / untmp / whidbey / REDBITS / ndp / fx / src / Data / System / Data / Common / SafeNativeMethods.cs / 1 / SafeNativeMethods.cs
                        

                        
                            //------------------------------------------------------------------------------ 
// 
//      Copyright (c) Microsoft Corporation.  All rights reserved.
// 
// [....] 
// [....]
// [....] 
//----------------------------------------------------------------------------- 

using System; 
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Security;
using System.Security.Permissions; 
using System.Text;
using System.Threading; 
using System.Runtime.ConstrainedExecution; 

namespace System.Data.Common { 

    [SuppressUnmanagedCodeSecurityAttribute()]
    internal static class SafeNativeMethods {
 
        [DllImport(ExternDll.Ole32, SetLastError=false)]
        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.MayFail)] 
        static internal extern IntPtr CoTaskMemAlloc(IntPtr cb); 

        [DllImport(ExternDll.Ole32, SetLastError=false)] 
        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.Success)]
        static internal extern void CoTaskMemFree(IntPtr handle);

        [DllImport(ExternDll.Kernel32, CharSet=CharSet.Unicode, PreserveSig=true)] 
        static internal extern int GetUserDefaultLCID();
 
#if !ORACLE 
        [DllImport(ExternDll.Kernel32, PreserveSig=true)]
        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.Success)] 
        static internal extern void ZeroMemory(IntPtr dest, IntPtr length);
#endif

        /*[DllImport(ExternDll.Kernel32)] 
        static internal extern IntPtr InterlockedCompareExchange(
            IntPtr Destination, // destination address 
            IntPtr Exchange,       // exchange value 
            IntPtr Comperand       // value to compare
           );*/ 

        // 
        // Using the int versions of the Increment() and Decrement() methods is correct.
        // Please check \fx\src\Data\System\Data\Odbc\OdbcHandle.cs for the memory layout. 
        // 
 
        //  
        // The following casting operations require these three methods to be unsafe.  This is
        // a workaround for this issue to meet the M1 exit criteria.  We need to revisit this in M2. 

        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.MayFail)]
        static internal unsafe IntPtr InterlockedExchangePointer(
                IntPtr lpAddress, 
                IntPtr lpValue)
        { 
            IntPtr  previousPtr; 
            IntPtr  actualPtr = *(IntPtr *)lpAddress.ToPointer();
 
            do {
                previousPtr = actualPtr;
                actualPtr   = Interlocked.CompareExchange(ref *(IntPtr *)lpAddress.ToPointer(), lpValue, previousPtr);
            } 
            while (actualPtr != previousPtr);
 
            return actualPtr; 
        }
 
        // http://msdn.microsoft.com/library/default.asp?url=/library/en-us/sysinfo/base/getcomputernameex.asp
        [DllImport(ExternDll.Kernel32, CharSet = CharSet.Unicode, EntryPoint="GetComputerNameExW", SetLastError=true)]
        static internal extern int GetComputerNameEx(int nameType, StringBuilder nameBuffer, ref int bufferSize);
 
        [DllImport(ExternDll.Kernel32, CharSet=System.Runtime.InteropServices.CharSet.Auto)]
        static internal extern int GetCurrentProcessId(); 
 
        [DllImport(ExternDll.Kernel32, CharSet=CharSet.Auto, BestFitMapping=false, ThrowOnUnmappableChar=true)]
//        [DllImport(ExternDll.Kernel32, CharSet=CharSet.Auto)] 
        static internal extern IntPtr GetModuleHandle([MarshalAs(UnmanagedType.LPTStr), In] string moduleName/*lpctstr*/);

        [DllImport(ExternDll.Kernel32, CharSet=CharSet.Ansi, BestFitMapping=false, ThrowOnUnmappableChar=true)]
//        [DllImport(ExternDll.Kernel32, CharSet=CharSet.Ansi)] 
        static internal extern IntPtr GetProcAddress(IntPtr HModule, [MarshalAs(UnmanagedType.LPStr), In] string funcName/*lpcstr*/);
 
        [DllImport(ExternDll.Kernel32)] 
        internal static extern void GetSystemTimeAsFileTime(out long lpSystemTimeAsFileTime);
 
        [DllImport(ExternDll.Kernel32, SetLastError=true)]
        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.MayFail)]
        static internal extern IntPtr LocalAlloc(int flags, IntPtr countOfBytes);
 
        [DllImport(ExternDll.Kernel32, SetLastError=true)]
        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.Success)] 
        static internal extern IntPtr LocalFree(IntPtr handle); 

        [DllImport(ExternDll.Oleaut32, CharSet=CharSet.Unicode)] 
        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.MayFail)]
        internal static extern IntPtr SysAllocStringLen(String src, int len);  // BSTR

        [DllImport(ExternDll.Oleaut32)] 
        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.Success)]
        internal static extern void SysFreeString(IntPtr bstr); 
 
        // only using this to clear existing error info with null
        [DllImport(ExternDll.Oleaut32, CharSet=CharSet.Unicode, PreserveSig=false)] 
        static private extern void SetErrorInfo(Int32 dwReserved, IntPtr pIErrorInfo);

        [DllImport(ExternDll.Kernel32, SetLastError=true)]
        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.MayFail)] 
        static internal extern int ReleaseSemaphore(IntPtr handle, int releaseCount, IntPtr previousCount);
 
        [DllImport(ExternDll.Kernel32, SetLastError=true)] 
        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.MayFail)]
        static internal extern int WaitForMultipleObjectsEx(uint nCount, IntPtr lpHandles, bool bWaitAll, uint dwMilliseconds, bool bAlertable); 

        [DllImport(ExternDll.Kernel32/*, SetLastError=true*/)]
        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.MayFail)]
        static internal extern int WaitForSingleObjectEx(IntPtr lpHandles, uint dwMilliseconds, bool bAlertable); 

        [DllImport(ExternDll.Ole32, PreserveSig=false)] 
        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.Success)] 
        static internal extern void PropVariantClear(IntPtr pObject);
 
        [DllImport(ExternDll.Oleaut32, PreserveSig=false)]
        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.Success)]
        static internal extern void VariantClear(IntPtr pObject);
 
        sealed internal class Wrapper {
 
            private Wrapper() { } 

            static internal void ClearErrorInfo() { // MDAC 68199 
                SafeNativeMethods.SetErrorInfo(0, ADP.PtrZero);
            }
        }
 

    } 
} 

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.

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