use Loadlibrary/GetProcAddress for XInput, rather than /DELAYLOAD

content/browser/gamepad/platform_data_fetcher_win.cc

Index: content/browser/gamepad/platform_data_fetcher_win.cc
diff --git a/content/browser/gamepad/platform_data_fetcher_win.cc b/content/browser/gamepad/platform_data_fetcher_win.cc
index 752328ae3e8d8141fcd1a349de1f1782a670f02f..e0d1fa52070187a1239ff202caf88f044c154763 100644
--- a/content/browser/gamepad/platform_data_fetcher_win.cc
+++ b/content/browser/gamepad/platform_data_fetcher_win.cc
@@ -8,15 +8,6 @@
 #include "content/common/gamepad_messages.h"
 #include "content/common/gamepad_hardware_buffer.h"
 
-#if defined(_WIN32_WINNT_WIN8)
-// The Windows 8 SDK defines FACILITY_VISUALCPP in winerror.h.
-#undef FACILITY_VISUALCPP
-#endif
-#include <delayimp.h>
-
-#pragma comment(lib, "delayimp.lib")
-#pragma comment(lib, "xinput.lib")
-
 namespace content {
 
 using namespace WebKit;
@@ -57,37 +48,11 @@ const WebUChar* const GamepadSubTypeName(BYTE sub_type) {
   }
 }
 
-// Trap only the exceptions that DELAYLOAD can throw, otherwise rethrow.
-// See http://msdn.microsoft.com/en-us/library/1c9e046h(v=VS.90).aspx.
-LONG WINAPI DelayLoadDllExceptionFilter(PEXCEPTION_POINTERS pExcPointers) {
-  LONG disposition = EXCEPTION_EXECUTE_HANDLER;
-  switch (pExcPointers->ExceptionRecord->ExceptionCode) {
-    case VcppException(ERROR_SEVERITY_ERROR, ERROR_MOD_NOT_FOUND):
-    case VcppException(ERROR_SEVERITY_ERROR, ERROR_PROC_NOT_FOUND):
-      break;
-    default:
-      // Exception is not related to delay loading.
-      disposition = EXCEPTION_CONTINUE_SEARCH;
-      break;
-  }
-  return disposition;
-}
-
-bool EnableXInput() {
-  // We have specified DELAYLOAD for xinput1_3.dll. If the DLL is not
-  // installed (XP w/o DirectX redist installed), we disable functionality.
-  __try {
-    XInputEnable(true);
-  } __except(DelayLoadDllExceptionFilter(GetExceptionInformation())) {
-    return false;
-  }
-  return true;
-}
-
 }  // namespace
 
-GamepadPlatformDataFetcherWin::GamepadPlatformDataFetcherWin()
-    : xinput_available_(EnableXInput()) {
+GamepadPlatformDataFetcherWin::GamepadPlatformDataFetcherWin() :
+    xinput_dll_(FilePath(L"xinput1_3.dll")),

[cpu_(ooo_6.6-7.5), 2012/07/17 19:30:46]

FILE_PATH_LITERAL("...")

+    xinput_available_(GetXinputDllFunctions()) {
 }
 
 void GamepadPlatformDataFetcherWin::GetGamepadData(WebGamepads* pads,
@@ -114,7 +79,7 @@ void GamepadPlatformDataFetcherWin::GetGamepadData(WebGamepads* pads,
       WebGamepad& pad = pads->items[i];
       TRACE_EVENT1("GAMEPAD", "GetCapabilities", "id", i);
       XINPUT_CAPABILITIES caps;
-      DWORD res = XInputGetCapabilities(i, XINPUT_FLAG_GAMEPAD, &caps);
+      DWORD res = xinput_get_capabilities_(i, XINPUT_FLAG_GAMEPAD, &caps);
       if (res == ERROR_DEVICE_NOT_CONNECTED) {
         pad.connected = false;
       } else {
@@ -141,7 +106,7 @@ void GamepadPlatformDataFetcherWin::GetGamepadData(WebGamepads* pads,
     XINPUT_STATE state;
     memset(&state, 0, sizeof(XINPUT_STATE));
     TRACE_EVENT_BEGIN1("GAMEPAD", "XInputGetState", "id", i);
-    DWORD dwResult = XInputGetState(i, &state);
+    DWORD dwResult = xinput_get_state_(i, &state);
     TRACE_EVENT_END1("GAMEPAD", "XInputGetState", "id", i);
 
     if (dwResult == ERROR_SUCCESS) {
@@ -178,4 +143,21 @@ void GamepadPlatformDataFetcherWin::GetGamepadData(WebGamepads* pads,
   }
 }
 
+bool GamepadPlatformDataFetcherWin::GetXinputDllFunctions() {
+  xinput_enable_ = static_cast<XInputEnableFunc>(
+      xinput_dll_.GetFunctionPointer("XInputEnable"));
+  if (!xinput_enable_)
+    return false;
+  xinput_get_capabilities_ = static_cast<XInputGetCapabilitiesFunc>(
+      xinput_dll_.GetFunctionPointer("XInputGetCapabilities"));
+  if (!xinput_get_capabilities_)
+    return false;
+  xinput_get_state_ = static_cast<XInputGetStateFunc>(
+      xinput_dll_.GetFunctionPointer("XInputGetState"));
+  if (!xinput_get_state_)
+    return false;
+  xinput_enable_(true);
+  return true;
+}
+
 }  // namespace content