7030249: Eliminate use of LoadLibrary and other clean-ups

[Dmytro Sheyko]

Maybe we should follow this approach (i.e. prefer GetModuleHandleEx to GetModuleHandle) in other places as well.

I found there suspect cases:

./jdk/src/windows/native/java/lang/java_props_md.c:                GetModuleHandle(TEXT("kernel32.dll")),

./jdk/test/java/util/Locale/data/deflocale.c:        HMODULE hmod = GetModuleHandle(L"kernel32");


./hotspot/src/os/windows/vm/perfMemory_windows.cpp:       GetProcAddress(GetModuleHandle(TEXT("advapi32.dll")),

./hotspot/src/os/windows/vm/os_windows.cpp:  hmod = GetModuleHandle("NTDLL.DLL");
./hotspot/src/os/windows/vm/os_windows.cpp:        HMODULE hKernel32 = GetModuleHandle(TEXT("kernel32.dll"));

./hotspot/src/os/windows/vm/os_windows.cpp:  HINSTANCE kernel32 = LoadLibrary("Kernel32.DLL") ;
./hotspot/src/os/windows/vm/os_windows.cpp:  HINSTANCE psapi = LoadLibrary( "PSAPI.DLL" ) ;

Regards,
Dmytro
Date: Tue, 29 Mar 2011 16:49:50 +0100
From: Alan.Bateman at oracle.com
To: dmytro_sheyko at hotmail.com
CC: core-libs-dev at openjdk.java.net
Subject: Re: 7030249: Eliminate use of LoadLibrary and other clean-ups






  
  Message body


Dmytro Sheyko wrote:

  
  :

  

Why we obtain HMODULE for kernel32 this way:

  

     // get handle to kernel32

     if (GetModuleHandleExW((GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS |

                            
GET_MODULE_HANDLE_EX_FLAG_UNCHANGED_REFCOUNT),

                            (LPCWSTR)&CreateFileW, &h) != 0)

     {

         ...

  

  

instead of

  

     handle = GetModuleHandle("kernel32");


GetModuleHandleExW allows you to provide the address of a function in
the library that you need the handle for and so you avoid issues when
multiple libraries with the same name are loaded.



:

  

Also according to MSDN GetModuleHandleEx requires at minimum "Windows
XP" or "Windows Server 2003". It means that we do not support "Windows
2000", right?


I don't think it's been possible to install or run jdk7 on Windows 2000
for some time.



-Alan