MFCreateMemoryBuffer

// MFPlat.dll
#include <windows.h>

HRESULT MFCreateMemoryBuffer(
    DWORD cbMaxLength,
    IMFMediaBuffer** ppBuffer
);

<DllImport("MFPlat.dll", ExactSpelling:=True)>
Public Shared Function MFCreateMemoryBuffer(
    cbMaxLength As UInteger,   ' DWORD
    ppBuffer As IntPtr   ' IMFMediaBuffer** out
) As Integer
End Function

' cbMaxLength : DWORD
' ppBuffer : IMFMediaBuffer** out
Declare PtrSafe Function MFCreateMemoryBuffer Lib "mfplat" ( _
    ByVal cbMaxLength As Long, _
    ByVal ppBuffer As LongPtr) As Long
' VBA7前提(PtrSafe)。32bit Office では LongPtr→Long。Integer=16bit / Long=32bit / LongLong=64bit。

import ctypes
from ctypes import wintypes

MFCreateMemoryBuffer = ctypes.windll.mfplat.MFCreateMemoryBuffer
MFCreateMemoryBuffer.restype = ctypes.c_int
MFCreateMemoryBuffer.argtypes = [
    wintypes.DWORD,  # cbMaxLength : DWORD
    ctypes.c_void_p,  # ppBuffer : IMFMediaBuffer** out
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('MFPlat.dll')
MFCreateMemoryBuffer = Fiddle::Function.new(
  lib['MFCreateMemoryBuffer'],
  [
    -Fiddle::TYPE_INT,  # cbMaxLength : DWORD
    Fiddle::TYPE_VOIDP,  # ppBuffer : IMFMediaBuffer** out
  ],
  Fiddle::TYPE_INT)

#[link(name = "mfplat")]
extern "system" {
    fn MFCreateMemoryBuffer(
        cbMaxLength: u32,  // DWORD
        ppBuffer: *mut *mut core::ffi::c_void  // IMFMediaBuffer** out
    ) -> i32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("MFPlat.dll")]
public static extern int MFCreateMemoryBuffer(uint cbMaxLength, IntPtr ppBuffer);
"@
$api = Add-Type -MemberDefinition $sig -Name 'MFPlat_MFCreateMemoryBuffer' -Namespace Win32 -PassThru
# $api::MFCreateMemoryBuffer(cbMaxLength, ppBuffer)

#uselib "MFPlat.dll"
#func global MFCreateMemoryBuffer "MFCreateMemoryBuffer" sptr, sptr
; MFCreateMemoryBuffer cbMaxLength, ppBuffer   ; 戻り値は stat
; cbMaxLength : DWORD -> "sptr"
; ppBuffer : IMFMediaBuffer** out -> "sptr"
; ※HSP3.7は #func のため戻り値はシステム変数 stat に格納されます。

#uselib "MFPlat.dll"
#cfunc global MFCreateMemoryBuffer "MFCreateMemoryBuffer" int, sptr
; res = MFCreateMemoryBuffer(cbMaxLength, ppBuffer)
; cbMaxLength : DWORD -> "int"
; ppBuffer : IMFMediaBuffer** out -> "sptr"

; HRESULT MFCreateMemoryBuffer(DWORD cbMaxLength, IMFMediaBuffer** ppBuffer)
#uselib "MFPlat.dll"
#cfunc global MFCreateMemoryBuffer "MFCreateMemoryBuffer" int, intptr
; res = MFCreateMemoryBuffer(cbMaxLength, ppBuffer)
; cbMaxLength : DWORD -> "int"
; ppBuffer : IMFMediaBuffer** out -> "intptr"

import (
	"golang.org/x/sys/windows"
	"unsafe"
)

var (
	mfplat = windows.NewLazySystemDLL("MFPlat.dll")
	procMFCreateMemoryBuffer = mfplat.NewProc("MFCreateMemoryBuffer")
)

// cbMaxLength (DWORD), ppBuffer (IMFMediaBuffer** out)
r1, _, err := procMFCreateMemoryBuffer.Call(
	uintptr(cbMaxLength),
	uintptr(ppBuffer),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // HRESULT

function MFCreateMemoryBuffer(
  cbMaxLength: DWORD;   // DWORD
  ppBuffer: Pointer   // IMFMediaBuffer** out
): Integer; stdcall;
  external 'MFPlat.dll' name 'MFCreateMemoryBuffer';

result := DllCall("MFPlat\MFCreateMemoryBuffer"
    , "UInt", cbMaxLength   ; DWORD
    , "Ptr", ppBuffer   ; IMFMediaBuffer** out
    , "Int")   ; return: HRESULT

●MFCreateMemoryBuffer(cbMaxLength, ppBuffer) = DLL("MFPlat.dll", "int MFCreateMemoryBuffer(dword, void*)")
# 呼び出し: MFCreateMemoryBuffer(cbMaxLength, ppBuffer)
# cbMaxLength : DWORD -> "dword"
# ppBuffer : IMFMediaBuffer** out -> "void*"
# なでしこ1は32bit・ANSI(Shift_JIS)。文字列=char*(ANSI)、ポインタ/ハンドル=void*(4byte)。