Still use HackDispatcher when using the old runtime since it doesn't …

…have any problems there

This is because we need to access the handles which wasn't exported til recently so 1.2.12 needs the hack. But if you are using the new runtime then you are likely using a newer version of Nim

asynctools/asyncipc.nim

@@ -130,6 +130,7 @@ elif defined(windows):
  ioPort: Handle
  handles: HashSet[AsyncFD]
  HackDispatcher = ptr HackDispatcherImpl
+ Dispatcher = HackDispatcher | PDispatcher
 
  proc openEvent(dwDesiredAccess: Dword, bInheritHandle: WINBOOL,
  lpName: WideCString): Handle
@@ -142,8 +143,22 @@ elif defined(windows):
  proc interlockedAnd(a: ptr int32, b: int32)
  {.importc: "_InterlockedAnd", header: "intrin.h".}
 
- proc getCurrentDispatcher(): HackDispatcher =
- result = cast[HackDispatcher](getGlobalDispatcher())
+ proc getCurrentDispatcher(): Dispatcher =
+ when defined(nimv2):
+ # New runtime will run into segfault if using HackDispatcher, but old versions of Nim require
+ # HackDispatcher so we can access some internal fields.
+ # If using the new runtime then likely using a new enough Nim version that the needed fields
+ # are exported
+ getGlobalDispatcher()
+ else:
+ cast[HackDispatcher](getGlobalDispatcher())
+
+ template getIoHandler(p: Dispatcher): Handle =
+ ## Returns the IO handle for a dispatcher.
+ when p is PDispatcher:
+ p.getIoHandler()
+ else:
+ p.ioPort
 
  proc `$`*(ipc: AsyncIpc): string =
  if ipc.handleMap == Handle(0):
@@ -266,7 +281,7 @@ elif defined(windows):
  interlockedOr(cast[ptr int32](data), 1)
 
  if register:
- let p = getGlobalDispatcher()
+ let p = getCurrentDispatcher()
  p.handles.incl(AsyncFD(eventChange))
 
  result = AsyncIpcHandle(
@@ -284,7 +299,7 @@ elif defined(windows):
  interlockedAnd(cast[ptr int32](ipch.data), not(1))
 
  if unregister:
- let p = getGlobalDispatcher()
+ let p = getCurrentDispatcher()
  p.handles.excl(AsyncFD(ipch.eventChange))
 
  if unmapViewOfFile(ipch.data) == 0:
@@ -321,7 +336,7 @@ elif defined(windows):
  template registerWaitableChange(ipc: AsyncIpcHandle, pcd, handleCallback) =
  let p = getCurrentDispatcher()
  var flags = (WT_EXECUTEINWAITTHREAD or WT_EXECUTEONLYONCE).Dword
- pcd.ioPort = cast[Handle](p.ioPort)
+ pcd.ioPort = p.getIoHandler()
  pcd.handleFd = AsyncFD(ipc.eventChange)
  var ol = PCustomOverlapped()
  GC_ref(ol)