Merge pull request #8850 from z2oh/cherrypick-windows-status-pending-delete

[🍒 stable/20230725] [Support] Handle delete_pending case for Windows fs::status (llvm#90655)

Author: compnerd

llvm/include/llvm/Support/Errc.h

@@ -38,6 +38,10 @@ enum class errc {
   bad_address = int(std::errc::bad_address),
   bad_file_descriptor = int(std::errc::bad_file_descriptor),
   broken_pipe = int(std::errc::broken_pipe),
+  // There is no delete_pending in std::errc; this error code is negative to
+  // avoid conflicts. This error roughly corresponds with Windows'
+  // STATUS_DELETE_PENDING 0xC0000056.
+  delete_pending = -56,
   device_or_resource_busy = int(std::errc::device_or_resource_busy),
   directory_not_empty = int(std::errc::directory_not_empty),
   executable_format_error = int(std::errc::executable_format_error),

llvm/include/llvm/Support/WindowsError.h

@@ -12,6 +12,7 @@
 #include <system_error>
 
 namespace llvm {
+std::error_code mapLastWindowsError();
 std::error_code mapWindowsError(unsigned EV);
 }
 

llvm/lib/Support/CMakeLists.txt

@@ -40,7 +40,8 @@ endif()
 if( MSVC OR MINGW )
   # libuuid required for FOLDERID_Profile usage in lib/Support/Windows/Path.inc.
   # advapi32 required for CryptAcquireContextW in lib/Support/Windows/Path.inc.
-  set(system_libs ${system_libs} psapi shell32 ole32 uuid advapi32)
+  # ntdll required for RtlGetLastNtStatus in lib/Support/ErrorHandling.cpp.
+  set(system_libs ${system_libs} psapi shell32 ole32 uuid advapi32 ws2_32 ntdll)
 elseif( CMAKE_HOST_UNIX )
   if( HAVE_LIBRT )
     set(system_libs ${system_libs} rt)

llvm/lib/Support/ErrorHandling.cpp

@@ -235,8 +235,43 @@ void LLVMResetFatalErrorHandler() {
 
 #ifdef _WIN32
 
+#define WIN32_NO_STATUS
+#include "llvm/Support/Windows/WindowsSupport.h"
+#undef WIN32_NO_STATUS
+#include <ntstatus.h>
 #include <winerror.h>
 
+// This is equivalent to NtCurrentTeb()->LastStatusValue, but the public
+// _TEB definition does not expose the LastStatusValue field directly.
+// Avoid offsetting into this structure by calling RtlGetLastNtStatus
+// from ntdll.dll.
+//
+// The return of this function will roughly match that of
+// GetLastError, but this lower level API disambiguates some cases
+// that GetLastError does not.
+//
+// For more information, see:
+// https://www.geoffchappell.com/studies/windows/km/ntoskrnl/inc/api/pebteb/teb/index.htm
+// https://github.com/llvm/llvm-project/issues/89137
+extern "C" NTSYSAPI NTSTATUS NTAPI RtlGetLastNtStatus();
+
+// This function obtains the last error code and maps it. It may call
+// RtlGetLastNtStatus, which is a lower level API that can return a
+// more specific error code than GetLastError.
+std::error_code llvm::mapLastWindowsError() {
+  unsigned EV = ::GetLastError();
+  // The mapping of NTSTATUS to Win32 error loses some information; special
+  // case the generic ERROR_ACCESS_DENIED code to check the underlying
+  // NTSTATUS and potentially return a more accurate error code.
+  if (EV == ERROR_ACCESS_DENIED) {
+    llvm::errc code = RtlGetLastNtStatus() == STATUS_DELETE_PENDING
+                          ? errc::delete_pending
+                          : errc::permission_denied;
+    return make_error_code(code);
+  }
+  return mapWindowsError(EV);
+}
+
 // I'd rather not double the line count of the following.
 #define MAP_ERR_TO_COND(x, y)                                                  \
   case x:                                                                      \

llvm/lib/Support/Windows/Path.inc

@@ -745,14 +745,14 @@ static std::error_code getStatus(HANDLE FileHandle, file_status &Result) {
   return std::error_code();
 
 handle_status_error:
-  DWORD LastError = ::GetLastError();
-  if (LastError == ERROR_FILE_NOT_FOUND || LastError == ERROR_PATH_NOT_FOUND)
+  std::error_code Err = mapLastWindowsError();
+  if (Err == std::errc::no_such_file_or_directory)
     Result = file_status(file_type::file_not_found);
-  else if (LastError == ERROR_SHARING_VIOLATION)
+  else if (Err == std::errc::permission_denied)
     Result = file_status(file_type::type_unknown);
   else
     Result = file_status(file_type::status_error);
-  return mapWindowsError(LastError);
+  return Err;
 }
 
 std::error_code status(const Twine &path, file_status &result, bool Follow) {