Merge pull request #12371 from rayman22201/IOSelector_unregister_fix

Test + fix for epoll and kqueue selector modules to properly unregister event handles that have the key type "User"

changelog.md

@@ -23,6 +23,8 @@
 
 ## Library changes
 
+- `asyncdispatch.drain` now properly takes into account `selector.hasPendingOperations` and only returns once all pending async operations are guaranteed to have completed.
+- `asyncdispatch.drain` now consistently uses the passed timeout value for all iterations of the event loop, and not just the first iteration. This is more consistent with the other asyncdispatch apis, and allows `asyncdispatch.drain` to be more efficient.
 - `base64.encode` and `base64.decode` was made faster by about 50%.
 - `htmlgen` adds [MathML](https://wikipedia.org/wiki/MathML) support (ISO 40314).
 
@@ -46,3 +48,4 @@
 
 ## Bugfixes
 
+- The `FD` variant of `selector.unregister` for `ioselector_epoll` and `ioselector_select` now properly handle the `Event.User` select event type.

lib/pure/asyncdispatch.nim

@@ -1559,8 +1559,8 @@ proc drain*(timeout = 500) =
   ## Waits for completion events and processes them. Raises ``ValueError``
   ## if there are no pending operations. In contrast to ``poll`` this
   ## processes as many events as are available.
-  if runOnce(timeout):
+  if runOnce(timeout) or hasPendingOperations():
-    while hasPendingOperations() and runOnce(0): discard
+    while hasPendingOperations() and runOnce(timeout): discard
 
 proc poll*(timeout = 500) =
   ## Waits for completion events and processes them. Raises ``ValueError``

lib/pure/ioselects/ioselectors_epoll.nim

@@ -197,7 +197,7 @@ proc unregister*[T](s: Selector[T], fd: int|SocketHandle) =
            "Descriptor $# is not registered in the selector!" % $fdi)
   if pkey.events != {}:
     when not defined(android):
-      if pkey.events * {Event.Read, Event.Write} != {}:
+      if Event.Read in pkey.events or Event.Write in pkey.events or Event.User in pkey.events:
         var epv = EpollEvent()
         # TODO: Refactor all these EPOLL_CTL_DEL + dec(s.count) into a proc.
         if epoll_ctl(s.epollFD, EPOLL_CTL_DEL, fdi.cint, addr epv) != 0:
@@ -237,7 +237,7 @@ proc unregister*[T](s: Selector[T], fd: int|SocketHandle) =
         if posix.close(cint(fdi)) != 0:
           raiseIOSelectorsError(osLastError())
     else:
-      if pkey.events * {Event.Read, Event.Write} != {}:
+      if Event.Read in pkey.events or Event.Write in pkey.events or Event.User in pkey.events:
         var epv = EpollEvent()
         if epoll_ctl(s.epollFD, EPOLL_CTL_DEL, fdi.cint, addr epv) != 0:
           raiseIOSelectorsError(osLastError())

lib/pure/ioselects/ioselectors_kqueue.nim

@@ -632,4 +632,4 @@ template withData*[T](s: Selector[T], fd: SocketHandle|int, value, body1,
 
 
 proc getFd*[T](s: Selector[T]): int =
-  return s.kqFD.int
+  return s.kqFD.int

lib/pure/ioselects/ioselectors_select.nim

@@ -286,7 +286,7 @@ proc unregister*[T](s: Selector[T], fd: SocketHandle|int) =
   s.withSelectLock():
     let fd = fd.SocketHandle
     var pkey = s.getKey(fd)
-    if Event.Read in pkey.events:
+    if Event.Read in pkey.events or Event.User in pkey.events:
       IOFD_CLR(fd, addr s.rSet)
       dec(s.count)
     if Event.Write in pkey.events:
@@ -462,4 +462,4 @@ template withData*[T](s: Selector[T], fd: SocketHandle|int, value,
 
 
 proc getFd*[T](s: Selector[T]): int =
-  return -1
+  return -1

tests/async/testmanyasyncevents.nim

@@ -0,0 +1,23 @@
+discard """
+output: '''
+hasPendingOperations: false
+triggerCount: 100 
+'''
+"""
+
+import asyncDispatch
+
+var triggerCount = 0
+var evs = newSeq[AsyncEvent]()
+
+for i in 0 ..< 100: # has to be lower than the typical physical fd limit
+  var ev = newAsyncEvent()
+  evs.add(ev)
+  addEvent(ev, proc(fd: AsyncFD): bool {.gcsafe,closure.} = triggerCount += 1; true)
+
+for ev in evs:
+  ev.trigger()
+
+drain()
+echo "hasPendingOperations: ", hasPendingOperations()
+echo "triggerCount: ", triggerCount