WSDUriDecode

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

HRESULT WSDUriDecode(
    LPCWSTR source,
    DWORD cchSource,
    LPWSTR* destOut,
    DWORD* cchDestOut   // optional
);

<DllImport("wsdapi.dll", ExactSpelling:=True)>
Public Shared Function WSDUriDecode(
    <MarshalAs(UnmanagedType.LPWStr)> source As String,   ' LPCWSTR
    cchSource As UInteger,   ' DWORD
    destOut As IntPtr,   ' LPWSTR* out
    cchDestOut As IntPtr   ' DWORD* optional, out
) As Integer
End Function

' source : LPCWSTR
' cchSource : DWORD
' destOut : LPWSTR* out
' cchDestOut : DWORD* optional, out
Declare PtrSafe Function WSDUriDecode Lib "wsdapi" ( _
    ByVal source As LongPtr, _
    ByVal cchSource As Long, _
    ByVal destOut As LongPtr, _
    ByVal cchDestOut 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

WSDUriDecode = ctypes.windll.wsdapi.WSDUriDecode
WSDUriDecode.restype = ctypes.c_int
WSDUriDecode.argtypes = [
    wintypes.LPCWSTR,  # source : LPCWSTR
    wintypes.DWORD,  # cchSource : DWORD
    ctypes.c_void_p,  # destOut : LPWSTR* out
    ctypes.POINTER(wintypes.DWORD),  # cchDestOut : DWORD* optional, out
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('wsdapi.dll')
WSDUriDecode = Fiddle::Function.new(
  lib['WSDUriDecode'],
  [
    Fiddle::TYPE_VOIDP,  # source : LPCWSTR
    -Fiddle::TYPE_INT,  # cchSource : DWORD
    Fiddle::TYPE_VOIDP,  # destOut : LPWSTR* out
    Fiddle::TYPE_VOIDP,  # cchDestOut : DWORD* optional, out
  ],
  Fiddle::TYPE_INT)

#[link(name = "wsdapi")]
extern "system" {
    fn WSDUriDecode(
        source: *const u16,  // LPCWSTR
        cchSource: u32,  // DWORD
        destOut: *mut *mut u16,  // LPWSTR* out
        cchDestOut: *mut u32  // DWORD* optional, out
    ) -> i32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("wsdapi.dll")]
public static extern int WSDUriDecode([MarshalAs(UnmanagedType.LPWStr)] string source, uint cchSource, IntPtr destOut, IntPtr cchDestOut);
"@
$api = Add-Type -MemberDefinition $sig -Name 'wsdapi_WSDUriDecode' -Namespace Win32 -PassThru
# $api::WSDUriDecode(source, cchSource, destOut, cchDestOut)

#uselib "wsdapi.dll"
#func global WSDUriDecode "WSDUriDecode" sptr, sptr, sptr, sptr
; WSDUriDecode source, cchSource, varptr(destOut), varptr(cchDestOut)   ; 戻り値は stat
; source : LPCWSTR -> "sptr"
; cchSource : DWORD -> "sptr"
; destOut : LPWSTR* out -> "sptr"
; cchDestOut : DWORD* optional, 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 "wsdapi.dll"
#cfunc global WSDUriDecode "WSDUriDecode" wstr, int, var, var
; res = WSDUriDecode(source, cchSource, destOut, cchDestOut)
; source : LPCWSTR -> "wstr"
; cchSource : DWORD -> "int"
; destOut : LPWSTR* out -> "var"
; cchDestOut : DWORD* optional, out -> "var"
; ※出力/バッファ引数は var 方式(変数を直接渡す)。varptr 方式にも切替可。

; HRESULT WSDUriDecode(LPCWSTR source, DWORD cchSource, LPWSTR* destOut, DWORD* cchDestOut)
#uselib "wsdapi.dll"
#cfunc global WSDUriDecode "WSDUriDecode" wstr, int, var, var
; res = WSDUriDecode(source, cchSource, destOut, cchDestOut)
; source : LPCWSTR -> "wstr"
; cchSource : DWORD -> "int"
; destOut : LPWSTR* out -> "var"
; cchDestOut : DWORD* optional, out -> "var"
; ※出力/バッファ引数は var 方式(変数を直接渡す)。varptr 方式にも切替可。

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

var (
	wsdapi = windows.NewLazySystemDLL("wsdapi.dll")
	procWSDUriDecode = wsdapi.NewProc("WSDUriDecode")
)

// source (LPCWSTR), cchSource (DWORD), destOut (LPWSTR* out), cchDestOut (DWORD* optional, out)
r1, _, err := procWSDUriDecode.Call(
	uintptr(unsafe.Pointer(windows.StringToUTF16Ptr(source))),
	uintptr(cchSource),
	uintptr(destOut),
	uintptr(cchDestOut),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // HRESULT

function WSDUriDecode(
  source: PWideChar;   // LPCWSTR
  cchSource: DWORD;   // DWORD
  destOut: PPWideChar;   // LPWSTR* out
  cchDestOut: Pointer   // DWORD* optional, out
): Integer; stdcall;
  external 'wsdapi.dll' name 'WSDUriDecode';

result := DllCall("wsdapi\WSDUriDecode"
    , "WStr", source   ; LPCWSTR
    , "UInt", cchSource   ; DWORD
    , "Ptr", destOut   ; LPWSTR* out
    , "Ptr", cchDestOut   ; DWORD* optional, out
    , "Int")   ; return: HRESULT

●WSDUriDecode(source, cchSource, destOut, cchDestOut) = DLL("wsdapi.dll", "int WSDUriDecode(char*, dword, void*, void*)")
# 呼び出し: WSDUriDecode(source, cchSource, destOut, cchDestOut)
# source : LPCWSTR -> "char*"
# cchSource : DWORD -> "dword"
# destOut : LPWSTR* out -> "void*"
# cchDestOut : DWORD* optional, 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)。