[libFuzzer] [Windows] Include windows.h and psapi.h with lowercase

[mstorsjo]

Summary

This fixes building on a case sensitive filesystem with mingw-w64 headers, where all headers are lowercase, and matches how these headers are included elsewhere in compiler-rt.

Also include these headers with angle brackets, as they are system headers.

[smeenai]

The existing capitalization (as in before your change) is the correct one for these headers in the Windows SDK, and it's also possible to cross-compile against the Windows SDK on a case-sensitive filesystem. However, doing that cross-compilation requires using a VFS overlay or case-correcting symlinks or ciopfs or whatever anyway, because the casing in the rest of the Windows SDK is hopelessly broken, so I'm okay with this change. I'll let @rnk confirm that it's okay to change the capitalization to the non-Windows SDK form though, and I'm also CCing @zturner since he also did cross-compilation work against the Windows SDK on Linux.

[mstorsjo]

In D51913#1230094, @smeenai wrote:

The existing capitalization (as in before your change) is the correct one for these headers in the Windows SDK,

FWIW, the second file is inconsistent in this regard as it includes windows.h but Psapi.h.

and it's also possible to cross-compile against the Windows SDK on a case-sensitive filesystem. However, doing that cross-compilation requires using a VFS overlay or case-correcting symlinks or ciopfs or whatever anyway, because the casing in the rest of the Windows SDK is hopelessly broken, so I'm okay with this change. I'll let @rnk confirm that it's okay to change the capitalization to the non-Windows SDK form though, and I'm also CCing @zturner since he also did cross-compilation work against the Windows SDK on Linux.

FWIW, I'm also occasionally doing cross-compilation with the Windows SDK (although mingw is what I'm spending most effort on), and my approach so far has been to run a script over the headers (and import libraries) to lowercase them, because they are, as you noted, hopelessly broken in their current form.

[mstorsjo]

In D51913#1230094, @smeenai wrote:

The existing capitalization (as in before your change) is the correct one for these headers in the Windows SDK, and it's also possible to cross-compile against the Windows SDK on a case-sensitive filesystem. However, doing that cross-compilation requires using a VFS overlay or case-correcting symlinks or ciopfs or whatever anyway, because the casing in the rest of the Windows SDK is hopelessly broken, so I'm okay with this change. I'll let @rnk confirm that it's okay to change the capitalization to the non-Windows SDK form though, and I'm also CCing @zturner since he also did cross-compilation work against the Windows SDK on Linux.

And fwiw about casing, within compiler-rt we already seem to have 63 occasions of lowercase windows.h and 1 occasion of lowercase psapi.h, so this change just brings these new cases in line with the existing status quo.

The day the windows sdk actually has self-consistent casing (and in case that casing isn't all lowercase), and people migrate code for cross-building towards using that spelling consistently, I guess mingw-w64 will have to start providing such casing as well in the form of symlinks.

[xbolva00]

lib/fuzzer/FuzzerExtFunctionsDlsymWin.cpp

16

<windows.h>

[mstorsjo]

Updated to use angle brackets for including system headers.

[smeenai]

All right, those are all fair arguments. LGTM.

lib/fuzzer/FuzzerExtFunctionsDlsymWin.cpp

 //===- FuzzerExtFunctionsDlsymWin.cpp - Interface to external functions ---===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 // Implementation using dynamic loading for Windows.
 //===----------------------------------------------------------------------===//
 #include "FuzzerDefs.h"
 #if LIBFUZZER_WINDOWS
 
 #include "FuzzerExtFunctions.h"
 #include "FuzzerIO.h"
-#include "Windows.h"
+#include <windows.h>
 
 // This must be included after Windows.h.
-#include "Psapi.h"
+#include <psapi.h>
 
 namespace fuzzer {
 
 ExternalFunctions::ExternalFunctions() {
   HMODULE Modules[1024];
   DWORD BytesNeeded;
   HANDLE CurrentProcess = GetCurrentProcess();
 

lib/fuzzer/FuzzerUtilWindows.cpp

 #include <errno.h>
 #include <iomanip>
 #include <signal.h>
 #include <stdio.h>
 #include <sys/types.h>
 #include <windows.h>
 
 // This must be included after windows.h.
-#include <Psapi.h>
+#include <psapi.h>
 
 namespace fuzzer {
 
 static const FuzzingOptions* HandlerOpt = nullptr;
 
 static LONG CALLBACK ExceptionHandler(PEXCEPTION_POINTERS ExceptionInfo) {
   switch (ExceptionInfo->ExceptionRecord->ExceptionCode) {
     case EXCEPTION_ACCESS_VIOLATION: