require 'windows/api'
include Windows

module Windows
   module Memory
      API.auto_namespace = 'Windows::Memory'
      API.auto_constant  = true
      API.auto_method    = true
      API.auto_unicode   = false

      GHND          = 0x0042
      GMEM_FIXED    = 0x0000
      GMEM_MOVABLE  = 0002
      GMEM_ZEROINIT = 0x0040
      GPTR          = 0x0040

      HEAP_NO_SERIALIZE          = 0x00000001
      HEAP_GENERATE_EXCEPTIONS   = 0x00000004
      HEAP_ZERO_MEMORY           = 0x00000008
      HEAP_REALLOC_IN_PLACE_ONLY = 0x00000010
      HEAP_CREATE_ENABLE_EXECUTE = 0x00040000
      
      MEM_COMMIT      = 0x1000
      MEM_RESERVE     = 0x2000
      MEM_DECOMMIT    = 0x4000
      MEM_RELEASE     = 0x8000
      MEM_FREE        = 0x10000
      MEM_PRIVATE     = 0x20000
      MEM_MAPPED      = 0x40000      
      MEM_RESET       = 0x80000
      MEM_TOP_DOWN    = 0x100000
      MEM_WRITE_WATCH = 0x200000
      MEM_PHYSICAL    = 0x400000      
      MEM_LARGE_PAGES = 0x20000000
      MEM_4MB_PAGES   = 0x80000000200000
      
      PAGE_NOACCESS          = 0x01     
      PAGE_READONLY          = 0x02     
      PAGE_READWRITE         = 0x04     
      PAGE_WRITECOPY         = 0x08     
      PAGE_EXECUTE           = 0x10     
      PAGE_EXECUTE_READ      = 0x20     
      PAGE_EXECUTE_READWRITE = 0x40     
      PAGE_EXECUTE_WRITECOPY = 0x80     
      PAGE_GUARD             = 0x100     
      PAGE_NOCACHE           = 0x200     
      PAGE_WRITECOMBINE      = 0x400
      
      SEC_FILE     = 0x800000     
      SEC_IMAGE    = 0x1000000     
      SEC_VLM      = 0x2000000     
      SEC_RESERVE  = 0x4000000     
      SEC_COMMIT   = 0x8000000     
      SEC_NOCACHE  = 0x10000000            

      LMEM_FIXED          = 0x0000
      LMEM_MOVEABLE       = 0x0002
      LMEM_NOCOMPACT      = 0x0010
      LMEM_NODISCARD      = 0x0020
      LMEM_ZEROINIT       = 0x0040
      LMEM_MODIFY         = 0x0080
      LMEM_DISCARDABLE    = 0x0F00
      LMEM_VALID_FLAGS    = 0x0F72
      LMEM_INVALID_HANDLE = 0x8000
      LMEM_DISCARDED      = 0x4000
      LMEM_LOCKCOUNT      = 0x00FF

      API.new('GlobalAlloc', 'II', 'I')
      API.new('GlobalFlags', 'I', 'I')
      API.new('GlobalFree', 'I', 'I')
      API.new('GlobalHandle', 'P', 'I')
      API.new('GlobalLock', 'L', 'L')
      API.new('GlobalMemoryStatus', 'P', 'V')
      API.new('GlobalMemoryStatusEx', 'P', 'V')
      API.new('GlobalReAlloc', 'III', 'I')
      API.new('GlobalSize', 'I', 'I')
      API.new('GlobalUnlock', 'I', 'I')

      API.new('GetProcessHeap', 'V', 'L')
      API.new('GetProcessHeaps', 'LP', 'L')
      API.new('HeapAlloc', 'LLL', 'P')
      API.new('HeapCompact', 'LL', 'L')
      API.new('HeapCreate', 'LLL', 'L')
      API.new('HeapDestroy', 'L', 'B')
      API.new('HeapFree', 'LLL', 'B')
      API.new('HeapLock', 'L', 'B')
      API.new('HeapReAlloc', 'LLLL', 'L')
      API.new('HeapSize', 'LLL', 'L')
      API.new('HeapUnlock', 'L', 'B')
      API.new('HeapValidate', 'LLL', 'B')
      API.new('HeapWalk', 'LP', 'B')

      API.new('LocalAlloc', 'IL', 'L')
      API.new('LocalFlags', 'L', 'I')
      API.new('LocalFree', 'L', 'L')
      API.new('LocalHandle', 'L', 'L')
      API.new('LocalLock', 'L', 'L')
      API.new('LocalReAlloc', 'LLI', 'L')
      API.new('LocalSize', 'L', 'I')
      API.new('LocalUnlock', 'L', 'B')

      API.new('VirtualAlloc', 'LLLL', 'L')
      API.new('VirtualAllocEx', 'LLLLL', 'L')
      API.new('VirtualFree', 'LLL', 'B')
      API.new('VirtualFreeEx', 'LLLL', 'B')
      API.new('VirtualLock', 'LL', 'B')
      API.new('VirtualProtect', 'LLLP', 'B')
      API.new('VirtualProtectEx', 'LLLLP', 'B')
      API.new('VirtualQuery', 'LPL', 'L')
      API.new('VirtualQueryEx', 'LLPL', 'L')
      API.new('VirtualUnlock', 'LL', 'B')
      API.new('RtlZeroMemory', 'PL', 'L')

      # The LocalDiscard macro from winbase.h
      def LocalDiscard(mem_loc)
         LocalReAlloc(mem_loc, 0, LMEM_MOVEABLE)
      end

      # Windows XP or later
      begin
         API.new('HeapQueryInformation', 'LIPLL', 'B')
         API.new('HeapSetInformation', 'LIPL', 'B')
      rescue Exception
         # Do nothing - you must check for their existence
      end
   end
end