windows-server-2003/base/fs/rdr2/rdbss/dav.mrx/webdav/server/midluser.c

/*++

Copyright (c) 1999  Microsoft Corporation

Module Name:

    MidlUser.c

Abstract:

    This file contains common functions and utilities that the API DLLs can use
    in making remote calls. This includes the MIDL_USER_* functions.

Author:

    Dan Lafferty    danl    06-Feb-1991

Environment:

    User Mode - Win32

Revision History:

    06-Feb-1991     danl
        Created

    25-Apr-1991    JohnRo
        Split out MIDL user (allocate, free) into seperate source file, so
        linker doesn't get confused.

    03-July-1991   JimK
        Moved to a common directory so services available to more than just
        LM code.

    03-Dec-1991 JohnRo
        Added MIDL_user_reallocate and MIDL_user_size APIs.  (These are so we
        create the NetApiBufferAllocate, NetApiBufferReallocate, and
        NetApiBufferSize APIs.)
        Also check alignment of allocated data.

    10-Feb-1993     RitaW
        Copied to the NetWare tree so that the LPC transport can used for
        the local case.

--*/

#include <nt.h>
#include <ntrtl.h>              // needed for nturtl.h
#include <nturtl.h>             // needed for windows.h
#include <windows.h>            // win32 typedefs
#include <rpc.h>                // rpc prototypes

#include <align.h>              // POINTER_IS_ALIGNED(), ALIGN_WORST.
#include <winbase.h>            // LocalAlloc


PVOID
MIDL_user_allocate (
    IN unsigned int NumBytes
    )

/*++

Routine Description:

    Allocates storage for RPC transactions. The RPC stubs will either call
    MIDL_user_allocate when it needs to un-marshall data into a buffer
    that the user must free.  RPC servers will use MIDL_user_allocate to
    allocate storage that the RPC server stub will free after marshalling
    the data.

Arguments:

    NumBytes - The number of bytes to allocate.

Return Value:

    NULL or the allocated pointer.

--*/

{
    LPVOID NewPointer;

    NewPointer = (LPVOID) LocalAlloc(LPTR, NumBytes);

    ASSERT( POINTER_IS_ALIGNED(NewPointer, ALIGN_WORST) );

    return (NewPointer);
}


VOID
MIDL_user_free (
    IN void *MemPointer
    )

/*++

Routine Description:

    Frees storage used in RPC transactions. The RPC client can call this
    function to free buffer space that was allocated by the RPC client
    stub when un-marshalling data that is to be returned to the client.
    The Client calls MIDL_user_free when it is finished with the data and
    desires to free up the storage. The RPC server stub calls MIDL_user_free
    when it has completed marshalling server data that is to be passed back to
    the client.

Arguments:

    MemPointer - This points to the memory block that is to be released.

Return Value:

    None.

--*/
{
    ASSERT( POINTER_IS_ALIGNED( MemPointer, ALIGN_WORST) );
    (void) LocalFree((HLOCAL) MemPointer);
}


void *
MIDL_user_reallocate(
    IN void * OldPointer OPTIONAL,
    IN unsigned long NewByteCount
    )
{
    LPVOID NewPointer;  // may be NULL.


    ASSERT( POINTER_IS_ALIGNED( OldPointer, ALIGN_WORST) );


    // Special cases: something into nothing, or nothing into something.
    if (OldPointer == NULL) {

        NewPointer = (LPVOID) LocalAlloc(
                                  LMEM_ZEROINIT,
                                  NewByteCount
                                  );

    } else if (NewByteCount == 0) {

        (void) LocalFree((HLOCAL) OldPointer );
        NewPointer = NULL;

    } else {  // must be realloc of something to something else.

        HANDLE hOldMem;
        HANDLE hNewMem;                     // handle for new (may = old handle)

        hOldMem = LocalHandle( (LPSTR) OldPointer);
        ASSERT(hOldMem != NULL);

        hNewMem = (PVOID) LocalReAlloc(
                              hOldMem,               // old handle
                              NewByteCount,          // new size in bytes
                              LMEM_ZEROINIT |        // flags
                                  LMEM_MOVEABLE      //  (motion okay)
                              );

        if (hNewMem == NULL) {
            return (NULL);
        }

        NewPointer = (LPVOID) hNewMem;

    } // must be realloc of something to something else

    ASSERT( POINTER_IS_ALIGNED( NewPointer, ALIGN_WORST) );

    return (NewPointer);

} // MIDL_user_reallocate


ULONG_PTR
MIDL_user_size(
    IN void * Pointer
    )
{
    ULONG_PTR ByteCount;
    HANDLE hMemory;

    ASSERT( Pointer != NULL );
    ASSERT( POINTER_IS_ALIGNED( Pointer, ALIGN_WORST ) );

    hMemory = LocalHandle( (LPSTR) Pointer );
    ASSERT( hMemory != NULL );

    ByteCount = LocalSize( hMemory );

    ASSERT( ByteCount > 0 );

    return (ByteCount);

} // MIDL_user_size