GetPaletteEntries

// GDI32.dll
#include <windows.h>

DWORD GetPaletteEntries(
    HPALETTE hpal,
    DWORD iStart,
    DWORD cEntries,
    PALETTEENTRY* pPalEntries   // optional
);

<DllImport("GDI32.dll", ExactSpelling:=True)>
Public Shared Function GetPaletteEntries(
    hpal As IntPtr,   ' HPALETTE
    iStart As UInteger,   ' DWORD
    cEntries As UInteger,   ' DWORD
    pPalEntries As IntPtr   ' PALETTEENTRY* optional, out
) As UInteger
End Function

' hpal : HPALETTE
' iStart : DWORD
' cEntries : DWORD
' pPalEntries : PALETTEENTRY* optional, out
Declare PtrSafe Function GetPaletteEntries Lib "gdi32" ( _
    ByVal hpal As LongPtr, _
    ByVal iStart As Long, _
    ByVal cEntries As Long, _
    ByVal pPalEntries 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

GetPaletteEntries = ctypes.windll.gdi32.GetPaletteEntries
GetPaletteEntries.restype = wintypes.DWORD
GetPaletteEntries.argtypes = [
    wintypes.HANDLE,  # hpal : HPALETTE
    wintypes.DWORD,  # iStart : DWORD
    wintypes.DWORD,  # cEntries : DWORD
    ctypes.c_void_p,  # pPalEntries : PALETTEENTRY* optional, out
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('GDI32.dll')
GetPaletteEntries = Fiddle::Function.new(
  lib['GetPaletteEntries'],
  [
    Fiddle::TYPE_VOIDP,  # hpal : HPALETTE
    -Fiddle::TYPE_INT,  # iStart : DWORD
    -Fiddle::TYPE_INT,  # cEntries : DWORD
    Fiddle::TYPE_VOIDP,  # pPalEntries : PALETTEENTRY* optional, out
  ],
  -Fiddle::TYPE_INT)

#[link(name = "gdi32")]
extern "system" {
    fn GetPaletteEntries(
        hpal: *mut core::ffi::c_void,  // HPALETTE
        iStart: u32,  // DWORD
        cEntries: u32,  // DWORD
        pPalEntries: *mut PALETTEENTRY  // PALETTEENTRY* optional, out
    ) -> u32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("GDI32.dll")]
public static extern uint GetPaletteEntries(IntPtr hpal, uint iStart, uint cEntries, IntPtr pPalEntries);
"@
$api = Add-Type -MemberDefinition $sig -Name 'GDI32_GetPaletteEntries' -Namespace Win32 -PassThru
# $api::GetPaletteEntries(hpal, iStart, cEntries, pPalEntries)

#uselib "GDI32.dll"
#func global GetPaletteEntries "GetPaletteEntries" sptr, sptr, sptr, sptr
; GetPaletteEntries hpal, iStart, cEntries, varptr(pPalEntries)   ; 戻り値は stat
; hpal : HPALETTE -> "sptr"
; iStart : DWORD -> "sptr"
; cEntries : DWORD -> "sptr"
; pPalEntries : PALETTEENTRY* 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 "GDI32.dll"
#cfunc global GetPaletteEntries "GetPaletteEntries" sptr, int, int, var
; res = GetPaletteEntries(hpal, iStart, cEntries, pPalEntries)
; hpal : HPALETTE -> "sptr"
; iStart : DWORD -> "int"
; cEntries : DWORD -> "int"
; pPalEntries : PALETTEENTRY* 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。

; DWORD GetPaletteEntries(HPALETTE hpal, DWORD iStart, DWORD cEntries, PALETTEENTRY* pPalEntries)
#uselib "GDI32.dll"
#cfunc global GetPaletteEntries "GetPaletteEntries" intptr, int, int, var
; res = GetPaletteEntries(hpal, iStart, cEntries, pPalEntries)
; hpal : HPALETTE -> "intptr"
; iStart : DWORD -> "int"
; cEntries : DWORD -> "int"
; pPalEntries : PALETTEENTRY* 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 (
	gdi32 = windows.NewLazySystemDLL("GDI32.dll")
	procGetPaletteEntries = gdi32.NewProc("GetPaletteEntries")
)

// hpal (HPALETTE), iStart (DWORD), cEntries (DWORD), pPalEntries (PALETTEENTRY* optional, out)
r1, _, err := procGetPaletteEntries.Call(
	uintptr(hpal),
	uintptr(iStart),
	uintptr(cEntries),
	uintptr(pPalEntries),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // DWORD

function GetPaletteEntries(
  hpal: THandle;   // HPALETTE
  iStart: DWORD;   // DWORD
  cEntries: DWORD;   // DWORD
  pPalEntries: Pointer   // PALETTEENTRY* optional, out
): DWORD; stdcall;
  external 'GDI32.dll' name 'GetPaletteEntries';

result := DllCall("GDI32\GetPaletteEntries"
    , "Ptr", hpal   ; HPALETTE
    , "UInt", iStart   ; DWORD
    , "UInt", cEntries   ; DWORD
    , "Ptr", pPalEntries   ; PALETTEENTRY* optional, out
    , "UInt")   ; return: DWORD

●GetPaletteEntries(hpal, iStart, cEntries, pPalEntries) = DLL("GDI32.dll", "dword GetPaletteEntries(void*, dword, dword, void*)")
# 呼び出し: GetPaletteEntries(hpal, iStart, cEntries, pPalEntries)
# hpal : HPALETTE -> "void*"
# iStart : DWORD -> "dword"
# cEntries : DWORD -> "dword"
# pPalEntries : PALETTEENTRY* 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)。