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/*
extern EFI_BOOT_SERVICES *gBS;
EFI_EXIT_BOOT_SERVICES gOrigExitBootServices;
EFI_STATUS
EFIAPI
ExitBootServicesHook(IN EFI_HANDLE ImageHandle, IN UINTN MapKey){
// <hook related fun>
// Do fun hook-related stuff here
// </hook-related fun>
// Fix the pointer in the boot services table
// If you don't do this, sometimes your hook method will be called repeatedly, which you don't want
gBS->ExitBootServices = gOrigExitBootServices;
// Get the memory map
UINTN MemoryMapSize;
EFI_MEMORY_DESCRIPTOR *MemoryMap;
UINTN LocalMapKey;
UINTN DescriptorSize;
UINT32 DescriptorVersion;
MemoryMap = NULL;
MemoryMapSize = 0;
do {
Status = gBS->GetMemoryMap(&MemoryMapSize, MemoryMap, &LocalMapKey, &DescriptorSize,&DescriptorVersion);
if (Status == EFI_BUFFER_TOO_SMALL){
MemoryMap = AllocatePool(MemoryMapSize + 1);
Status = gBS->GetMemoryMap(&MemoryMapSize, MemoryMap, &LocalMapKey, &DescriptorSize,&DescriptorVersion);
} else {
// Status is likely success - let the while() statement check success
}
DbgPrint(L"This time through the memory map loop, status = %r\n",Status);
} while (Status != EFI_SUCCESS);
return gOrigExitBootServices(ImageHandle,LocalMapKey);
}
EFI_STATUS
EFIAPI
HookDriverMain(IN EFI_HANDLE ImageHandle, IN EFI_SYSTEM_TABLE *SystemTable){
// Store off the original pointer and replace it with your own
gOrigExitBootServices = gBS->ExitBootServices;
gBS->ExitBootServices = ExitBootServicesHook;
// It's hooked! Return EFI_SUCCESS so your driver stays in memory
return EFI_SUCCESS;
}
*/
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