Async upcoming (#6585)

* Merge upcoming async with current.
* Various improvements to selectors (mostly docs).

Two changes to highlight:

* Renamed ``setEvent`` to ``trigger``
* Reused setBlocking from nativesockets.
* Various changes/fixes to asyncdispatch after upcoming merge.
* Make some attempts to be compatible with older selectors.
* Reuse epoll module in ioselectors_epoll.

lib/posix/epoll.nim

@@ -35,18 +35,13 @@ const
   EPOLL_CTL_MOD* = 3          # Change file descriptor epoll_event structure.
 
 type
-  epoll_data* {.importc: "union epoll_data",
+  EpollData* {.importc: "union epoll_data",
       header: "<sys/epoll.h>", pure, final.} = object # TODO: This is actually a union.
-    #thePtr* {.importc: "ptr".}: pointer
+    u64* {.importc: "u64".}: uint64
-    fd* {.importc: "fd".}: cint
-    when defined(linux) and defined(amd64):
-      u32: uint32 # this field ensures that binary size is right - it cannot be
-                  # used because its offset is wrong
-    #u64*: uint64
 
-  epoll_event* {.importc: "struct epoll_event", header: "<sys/epoll.h>", pure, final.} = object
+  EpollEvent* {.importc: "struct epoll_event", header: "<sys/epoll.h>", pure, final.} = object
     events*: uint32 # Epoll events
-    data*: epoll_data # User data variable
+    data*: EpollData # User data variable
 
 proc epoll_create*(size: cint): cint {.importc: "epoll_create",
     header: "<sys/epoll.h>".}
@@ -60,7 +55,7 @@ proc epoll_create1*(flags: cint): cint {.importc: "epoll_create1",
   ## Same as epoll_create but with an FLAGS parameter.  The unused SIZE
   ##   parameter has been dropped.
 
-proc epoll_ctl*(epfd: cint; op: cint; fd: cint | SocketHandle; event: ptr epoll_event): cint {.
+proc epoll_ctl*(epfd: cint; op: cint; fd: cint | SocketHandle; event: ptr EpollEvent): cint {.
     importc: "epoll_ctl", header: "<sys/epoll.h>".}
   ## Manipulate an epoll instance "epfd". Returns 0 in case of success,
   ##   -1 in case of error ( the "errno" variable will contain the
@@ -69,7 +64,7 @@ proc epoll_ctl*(epfd: cint; op: cint; fd: cint | SocketHandle; event: ptr epoll_
   ##   operation. The "event" parameter describes which events the caller
   ##   is interested in and any associated user data.
 
-proc epoll_wait*(epfd: cint; events: ptr epoll_event; maxevents: cint;
+proc epoll_wait*(epfd: cint; events: ptr EpollEvent; maxevents: cint;
                  timeout: cint): cint {.importc: "epoll_wait",
     header: "<sys/epoll.h>".}
   ## Wait for events on an epoll instance "epfd". Returns the number of
@@ -84,7 +79,7 @@ proc epoll_wait*(epfd: cint; events: ptr epoll_event; maxevents: cint;
   ##   __THROW.
 
 
-#proc epoll_pwait*(epfd: cint; events: ptr epoll_event; maxevents: cint;
+#proc epoll_pwait*(epfd: cint; events: ptr EpollEvent; maxevents: cint;
 #                  timeout: cint; ss: ptr sigset_t): cint {.
 #    importc: "epoll_pwait", header: "<sys/epoll.h>".}
 # Same as epoll_wait, but the thread's signal mask is temporarily

lib/pure/asyncdispatch.nim

@@ -9,8 +9,9 @@
 
 include "system/inclrtl"
 
-import os, tables, strutils, times, heapqueue, options, asyncstreams
+import os, tables, strutils, times, heapqueue, lists, options, asyncstreams
 import asyncfutures except callSoon
+
 import nativesockets, net, deques
 
 export Port, SocketFlag
@@ -136,6 +137,7 @@ export asyncfutures, asyncstreams
 ## and occasionally the compilation may fail altogether.
 ## As such it is better to use the former style when possible.
 ##
+##
 ## Discarding futures
 ## ------------------
 ##
@@ -226,6 +228,12 @@ when defined(windows) or defined(nimdoc):
       ovl: PCustomOverlapped
     PostCallbackDataPtr = ptr PostCallbackData
 
+    AsyncEventImpl = object
+      hEvent: Handle
+      hWaiter: Handle
+      pcd: PostCallbackDataPtr
+    AsyncEvent* = ptr AsyncEventImpl
+
     Callback = proc (fd: AsyncFD): bool {.closure,gcsafe.}
   {.deprecated: [TCompletionKey: CompletionKey, TAsyncFD: AsyncFD,
                 TCustomOverlapped: CustomOverlapped, TCompletionData: CompletionData].}
@@ -332,9 +340,9 @@ when defined(windows) or defined(nimdoc):
     # Callback queue processing
     processPendingCallbacks(p)
 
-  var connectExPtr: pointer = nil
+  var acceptEx: WSAPROC_ACCEPTEX
-  var acceptExPtr: pointer = nil
+  var connectEx: WSAPROC_CONNECTEX
-  var getAcceptExSockAddrsPtr: pointer = nil
+  var getAcceptExSockAddrs: WSAPROC_GETACCEPTEXSOCKADDRS
 
   proc initPointer(s: SocketHandle, fun: var pointer, guid: var GUID): bool =
     # Ref: https://github.com/powdahound/twisted/blob/master/twisted/internet/iocpreactor/iocpsupport/winsock_pointers.c
@@ -346,56 +354,19 @@ when defined(windows) or defined(nimdoc):
 
   proc initAll() =
     let dummySock = newNativeSocket()
-    if not initPointer(dummySock, connectExPtr, WSAID_CONNECTEX):
+    if dummySock == INVALID_SOCKET:
       raiseOSError(osLastError())
-    if not initPointer(dummySock, acceptExPtr, WSAID_ACCEPTEX):
+    var fun: pointer = nil
+    if not initPointer(dummySock, fun, WSAID_CONNECTEX):
       raiseOSError(osLastError())
-    if not initPointer(dummySock, getAcceptExSockAddrsPtr, WSAID_GETACCEPTEXSOCKADDRS):
+    connectEx = cast[WSAPROC_CONNECTEX](fun)
+    if not initPointer(dummySock, fun, WSAID_ACCEPTEX):
       raiseOSError(osLastError())
-
+    acceptEx = cast[WSAPROC_ACCEPTEX](fun)
-  proc connectEx(s: SocketHandle, name: ptr SockAddr, namelen: cint,
+    if not initPointer(dummySock, fun, WSAID_GETACCEPTEXSOCKADDRS):
-                  lpSendBuffer: pointer, dwSendDataLength: Dword,
+      raiseOSError(osLastError())
-                  lpdwBytesSent: PDword, lpOverlapped: POVERLAPPED): bool =
+    getAcceptExSockAddrs = cast[WSAPROC_GETACCEPTEXSOCKADDRS](fun)
-    if connectExPtr.isNil: raise newException(ValueError, "Need to initialise ConnectEx().")
+    close(dummySock)
-    let fun =
-      cast[proc (s: SocketHandle, name: ptr SockAddr, namelen: cint,
-         lpSendBuffer: pointer, dwSendDataLength: Dword,
-         lpdwBytesSent: PDword, lpOverlapped: POVERLAPPED): bool {.stdcall,gcsafe.}](connectExPtr)
-
-    result = fun(s, name, namelen, lpSendBuffer, dwSendDataLength, lpdwBytesSent,
-         lpOverlapped)
-
-  proc acceptEx(listenSock, acceptSock: SocketHandle, lpOutputBuffer: pointer,
-                 dwReceiveDataLength, dwLocalAddressLength,
-                 dwRemoteAddressLength: Dword, lpdwBytesReceived: PDword,
-                 lpOverlapped: POVERLAPPED): bool =
-    if acceptExPtr.isNil: raise newException(ValueError, "Need to initialise AcceptEx().")
-    let fun =
-      cast[proc (listenSock, acceptSock: SocketHandle, lpOutputBuffer: pointer,
-                 dwReceiveDataLength, dwLocalAddressLength,
-                 dwRemoteAddressLength: Dword, lpdwBytesReceived: PDword,
-                 lpOverlapped: POVERLAPPED): bool {.stdcall,gcsafe.}](acceptExPtr)
-    result = fun(listenSock, acceptSock, lpOutputBuffer, dwReceiveDataLength,
-        dwLocalAddressLength, dwRemoteAddressLength, lpdwBytesReceived,
-        lpOverlapped)
-
-  proc getAcceptExSockaddrs(lpOutputBuffer: pointer,
-      dwReceiveDataLength, dwLocalAddressLength, dwRemoteAddressLength: Dword,
-      LocalSockaddr: ptr ptr SockAddr, LocalSockaddrLength: LPInt,
-      RemoteSockaddr: ptr ptr SockAddr, RemoteSockaddrLength: LPInt) =
-    if getAcceptExSockAddrsPtr.isNil:
-      raise newException(ValueError, "Need to initialise getAcceptExSockAddrs().")
-
-    let fun =
-      cast[proc (lpOutputBuffer: pointer,
-                 dwReceiveDataLength, dwLocalAddressLength,
-                 dwRemoteAddressLength: Dword, LocalSockaddr: ptr ptr SockAddr,
-                 LocalSockaddrLength: LPInt, RemoteSockaddr: ptr ptr SockAddr,
-                RemoteSockaddrLength: LPInt) {.stdcall,gcsafe.}](getAcceptExSockAddrsPtr)
-
-    fun(lpOutputBuffer, dwReceiveDataLength, dwLocalAddressLength,
-                  dwRemoteAddressLength, LocalSockaddr, LocalSockaddrLength,
-                  RemoteSockaddr, RemoteSockaddrLength)
 
   proc recv*(socket: AsyncFD, size: int,
              flags = {SocketFlag.SafeDisconn}): Future[string] =
@@ -506,10 +477,7 @@ when defined(windows) or defined(nimdoc):
       proc (fd: AsyncFD, bytesCount: Dword, errcode: OSErrorCode) =
         if not retFuture.finished:
           if errcode == OSErrorCode(-1):
-            if bytesCount == 0 and dataBuf.buf[0] == '\0':
+            retFuture.complete(bytesCount)
-              retFuture.complete(0)
-            else:
-              retFuture.complete(bytesCount)
           else:
             if flags.isDisconnectionError(errcode):
               retFuture.complete(0)
@@ -543,10 +511,11 @@ when defined(windows) or defined(nimdoc):
 
   proc send*(socket: AsyncFD, buf: pointer, size: int,
              flags = {SocketFlag.SafeDisconn}): Future[void] =
-    ## Sends ``size`` bytes from ``buf`` to ``socket``. The returned future will complete once all
+    ## Sends ``size`` bytes from ``buf`` to ``socket``. The returned future
-    ## data has been sent.
+    ## will complete once all data has been sent.
-    ## **WARNING**: Use it with caution. If ``buf`` refers to GC'ed object, you must use GC_ref/GC_unref calls
+    ##
-    ## to avoid early freeing of the buffer
+    ## **WARNING**: Use it with caution. If ``buf`` refers to GC'ed object,
+    ## you must use GC_ref/GC_unref calls to avoid early freeing of the buffer.
     verifyPresence(socket)
     var retFuture = newFuture[void]("send")
 
@@ -793,7 +762,7 @@ when defined(windows) or defined(nimdoc):
                                        cast[pointer](p.ovl))
   {.pop.}
 
-  template registerWaitableEvent(mask) =
+  proc registerWaitableEvent(fd: AsyncFD, cb: Callback; mask: Dword) =
     let p = getGlobalDispatcher()
     var flags = (WT_EXECUTEINWAITTHREAD or WT_EXECUTEONLYONCE).Dword
     var hEvent = wsaCreateEvent()
@@ -843,8 +812,8 @@ when defined(windows) or defined(nimdoc):
                                        cast[pointer](pcd), INFINITE, flags):
               # pcd.ovl will be unrefed in poll()
               let err = osLastError()
-              discard wsaCloseEvent(hEvent)
               deallocShared(cast[pointer](pcd))
+              discard wsaCloseEvent(hEvent)
               raiseOSError(err)
             else:
               # we incref `pcd.ovl` and `protect` callback one more time,
@@ -883,16 +852,17 @@ when defined(windows) or defined(nimdoc):
     ##
     ## This is not ``pure`` mechanism for Windows Completion Ports (IOCP),
     ## so if you can avoid it, please do it. Use `addRead` only if really
-    ## need it (main usecase is adaptation of `unix like` libraries to be
+    ## need it (main usecase is adaptation of unix-like libraries to be
     ## asynchronous on Windows).
-    ## If you use this function, you dont need to use asyncdispatch.recv()
+    ##
+    ## If you use this function, you don't need to use asyncdispatch.recv()
     ## or asyncdispatch.accept(), because they are using IOCP, please use
     ## nativesockets.recv() and nativesockets.accept() instead.
     ##
     ## Be sure your callback ``cb`` returns ``true``, if you want to remove
     ## watch of `read` notifications, and ``false``, if you want to continue
-    ## receiving notifies.
+    ## receiving notifications.
-    registerWaitableEvent(FD_READ or FD_ACCEPT or FD_OOB or FD_CLOSE)
+    registerWaitableEvent(fd, cb, FD_READ or FD_ACCEPT or FD_OOB or FD_CLOSE)
 
   proc addWrite*(fd: AsyncFD, cb: Callback) =
     ## Start watching the file descriptor for write availability and then call
@@ -900,43 +870,213 @@ when defined(windows) or defined(nimdoc):
     ##
     ## This is not ``pure`` mechanism for Windows Completion Ports (IOCP),
     ## so if you can avoid it, please do it. Use `addWrite` only if really
-    ## need it (main usecase is adaptation of `unix like` libraries to be
+    ## need it (main usecase is adaptation of unix-like libraries to be
     ## asynchronous on Windows).
-    ## If you use this function, you dont need to use asyncdispatch.send()
+    ##
+    ## If you use this function, you don't need to use asyncdispatch.send()
     ## or asyncdispatch.connect(), because they are using IOCP, please use
     ## nativesockets.send() and nativesockets.connect() instead.
     ##
     ## Be sure your callback ``cb`` returns ``true``, if you want to remove
     ## watch of `write` notifications, and ``false``, if you want to continue
-    ## receiving notifies.
+    ## receiving notifications.
-    registerWaitableEvent(FD_WRITE or FD_CONNECT or FD_CLOSE)
+    registerWaitableEvent(fd, cb, FD_WRITE or FD_CONNECT or FD_CLOSE)
+
+  template registerWaitableHandle(p, hEvent, flags, pcd, timeout,
+                                  handleCallback) =
+    let handleFD = AsyncFD(hEvent)
+    pcd.ioPort = p.ioPort
+    pcd.handleFd = handleFD
+    var ol = PCustomOverlapped()
+    GC_ref(ol)
+    ol.data.fd = handleFD
+    ol.data.cb = handleCallback
+    # We need to protect our callback environment value, so GC will not free it
+    # accidentally.
+    ol.data.cell = system.protect(rawEnv(ol.data.cb))
+
+    pcd.ovl = ol
+    if not registerWaitForSingleObject(addr(pcd.waitFd), hEvent,
+                                    cast[WAITORTIMERCALLBACK](waitableCallback),
+                                    cast[pointer](pcd), timeout.Dword, flags):
+      let err = osLastError()
+      GC_unref(ol)
+      deallocShared(cast[pointer](pcd))
+      discard closeHandle(hEvent)
+      raiseOSError(err)
+    p.handles.incl(handleFD)
+
+  template closeWaitable(handle: untyped) =
+    let waitFd = pcd.waitFd
+    deallocShared(cast[pointer](pcd))
+    p.handles.excl(fd)
+    if unregisterWait(waitFd) == 0:
+        let err = osLastError()
+        if err.int32 != ERROR_IO_PENDING:
+          discard closeHandle(handle)
+          raiseOSError(err)
+    if closeHandle(handle) == 0:
+      raiseOSError(osLastError())
+
+  proc addTimer*(timeout: int, oneshot: bool, cb: Callback) =
+    ## Registers callback ``cb`` to be called when timer expired.
+    ##
+    ## Parameters:
+    ##
+    ## * ``timeout`` - timeout value in milliseconds.
+    ## * ``oneshot``
+    ##   * `true` - generate only one timeout event
+    ##   * `false` - generate timeout events periodically
+
+    doAssert(timeout > 0)
+    let p = getGlobalDispatcher()
+
+    var hEvent = createEvent(nil, 1, 0, nil)
+    if hEvent == INVALID_HANDLE_VALUE:
+      raiseOSError(osLastError())
+
+    var pcd = cast[PostCallbackDataPtr](allocShared0(sizeof(PostCallbackData)))
+    var flags = WT_EXECUTEINWAITTHREAD.Dword
+    if oneshot: flags = flags or WT_EXECUTEONLYONCE
+
+    proc timercb(fd: AsyncFD, bytesCount: Dword, errcode: OSErrorCode) =
+      let res = cb(fd)
+      if res or oneshot:
+        closeWaitable(hEvent)
+      else:
+        # if callback returned `false`, then it wants to be called again, so
+        # we need to ref and protect `pcd.ovl` again, because it will be
+        # unrefed and disposed in `poll()`.
+        GC_ref(pcd.ovl)
+        pcd.ovl.data.cell = system.protect(rawEnv(pcd.ovl.data.cb))
+
+    registerWaitableHandle(p, hEvent, flags, pcd, timeout, timercb)
+
+  proc addProcess*(pid: int, cb: Callback) =
+    ## Registers callback ``cb`` to be called when process with process ID
+    ## ``pid`` exited.
+    let p = getGlobalDispatcher()
+    let procFlags = SYNCHRONIZE
+    var hProcess = openProcess(procFlags, 0, pid.Dword)
+    if hProcess == INVALID_HANDLE_VALUE:
+      raiseOSError(osLastError())
+
+    var pcd = cast[PostCallbackDataPtr](allocShared0(sizeof(PostCallbackData)))
+    var flags = WT_EXECUTEINWAITTHREAD.Dword
+
+    proc proccb(fd: AsyncFD, bytesCount: Dword, errcode: OSErrorCode) =
+      closeWaitable(hProcess)
+      discard cb(fd)
+
+    registerWaitableHandle(p, hProcess, flags, pcd, INFINITE, proccb)
+
+  proc newAsyncEvent*(): AsyncEvent =
+    ## Creates a new thread-safe ``AsyncEvent`` object.
+    ##
+    ## New ``AsyncEvent`` object is not automatically registered with             # TODO: Why? -- DP
+    ## dispatcher like ``AsyncSocket``.
+    var sa = SECURITY_ATTRIBUTES(
+      nLength: sizeof(SECURITY_ATTRIBUTES).cint,
+      bInheritHandle: 1
+    )
+    var event = createEvent(addr(sa), 0'i32, 0'i32, nil)
+    if event == INVALID_HANDLE_VALUE:
+      raiseOSError(osLastError())
+    result = cast[AsyncEvent](allocShared0(sizeof(AsyncEventImpl)))
+    result.hEvent = event
+
+  proc trigger*(ev: AsyncEvent) =
+    ## Set event ``ev`` to signaled state.
+    if setEvent(ev.hEvent) == 0:
+      raiseOSError(osLastError())
+
+  proc unregister*(ev: AsyncEvent) =
+    ## Unregisters event ``ev``.
+    doAssert(ev.hWaiter != 0, "Event is not registered in the queue!")
+    let p = getGlobalDispatcher()
+    p.handles.excl(AsyncFD(ev.hEvent))
+    if unregisterWait(ev.hWaiter) == 0:
+      let err = osLastError()
+      if err.int32 != ERROR_IO_PENDING:
+        raiseOSError(err)
+    ev.hWaiter = 0
+
+  proc close*(ev: AsyncEvent) =
+    ## Closes event ``ev``.
+    let res = closeHandle(ev.hEvent)
+    deallocShared(cast[pointer](ev))
+    if res == 0:
+      raiseOSError(osLastError())
+
+  proc addEvent*(ev: AsyncEvent, cb: Callback) =
+    ## Registers callback ``cb`` to be called when ``ev`` will be signaled
+    doAssert(ev.hWaiter == 0, "Event is already registered in the queue!")
+
+    let p = getGlobalDispatcher()
+    let hEvent = ev.hEvent
+
+    var pcd = cast[PostCallbackDataPtr](allocShared0(sizeof(PostCallbackData)))
+    var flags = WT_EXECUTEINWAITTHREAD.Dword
+
+    proc eventcb(fd: AsyncFD, bytesCount: Dword, errcode: OSErrorCode) =
+      if ev.hWaiter != 0:
+        if cb(fd):
+          # we need this check to avoid exception, if `unregister(event)` was
+          # called in callback.
+          deallocShared(cast[pointer](pcd))
+          if ev.hWaiter != 0:
+            unregister(ev)
+        else:
+          # if callback returned `false`, then it wants to be called again, so
+          # we need to ref and protect `pcd.ovl` again, because it will be
+          # unrefed and disposed in `poll()`.
+          GC_ref(pcd.ovl)
+          pcd.ovl.data.cell = system.protect(rawEnv(pcd.ovl.data.cb))
+      else:
+        # if ev.hWaiter == 0, then event was unregistered before `poll()` call.
+        deallocShared(cast[pointer](pcd))
+
+    registerWaitableHandle(p, hEvent, flags, pcd, INFINITE, eventcb)
+    ev.hWaiter = pcd.waitFd
 
   initAll()
 else:
   import selectors
   from posix import EINTR, EAGAIN, EINPROGRESS, EWOULDBLOCK, MSG_PEEK,
                     MSG_NOSIGNAL
-
+  const
+    InitCallbackListSize = 4         # initial size of callbacks sequence,
+                                     # associated with file/socket descriptor.
+    InitDelayedCallbackListSize = 64 # initial size of delayed callbacks
+                                     # queue.
   type
     AsyncFD* = distinct cint
     Callback = proc (fd: AsyncFD): bool {.closure,gcsafe.}
 
-    PData* = ref object of RootRef
+    AsyncData = object
-      fd: AsyncFD
+      readList: seq[Callback]
-      readCBs: seq[Callback]
+      writeList: seq[Callback]
-      writeCBs: seq[Callback]
+
+    AsyncEvent* = distinct SelectEvent
 
     PDispatcher* = ref object of PDispatcherBase
-      selector: Selector
+      selector: Selector[AsyncData]
   {.deprecated: [TAsyncFD: AsyncFD, TCallback: Callback].}
 
   proc `==`*(x, y: AsyncFD): bool {.borrow.}
+  proc `==`*(x, y: AsyncEvent): bool {.borrow.}
+
+  template newAsyncData(): AsyncData =
+    AsyncData(
+      readList: newSeqOfCap[Callback](InitCallbackListSize),
+      writeList: newSeqOfCap[Callback](InitCallbackListSize)
+    )
 
   proc newDispatcher*(): PDispatcher =
     new result
-    result.selector = newSelector()
+    result.selector = newSelector[AsyncData]()
     result.timers.newHeapQueue()
-    result.callbacks = initDeque[proc ()](64)
+    result.callbacks = initDeque[proc ()](InitDelayedCallbackListSize)
 
   var gDisp{.threadvar.}: PDispatcher ## Global dispatcher
 
@@ -951,15 +1091,10 @@ else:
       setGlobalDispatcher(newDispatcher())
     result = gDisp
 
-  proc update(fd: AsyncFD, events: set[Event]) =
-    let p = getGlobalDispatcher()
-    assert fd.SocketHandle in p.selector
-    p.selector.update(fd.SocketHandle, events)
-
   proc register*(fd: AsyncFD) =
     let p = getGlobalDispatcher()
-    var data = PData(fd: fd, readCBs: @[], writeCBs: @[])
+    var data = newAsyncData()
-    p.selector.register(fd.SocketHandle, {}, data.RootRef)
+    p.selector.registerHandle(fd.SocketHandle, {}, data)
 
   proc closeSocket*(sock: AsyncFD) =
     let disp = getGlobalDispatcher()
@@ -969,75 +1104,148 @@ else:
   proc unregister*(fd: AsyncFD) =
     getGlobalDispatcher().selector.unregister(fd.SocketHandle)
 
+  proc unregister*(ev: AsyncEvent) =
+    getGlobalDispatcher().selector.unregister(SelectEvent(ev))
+
   proc addRead*(fd: AsyncFD, cb: Callback) =
     let p = getGlobalDispatcher()
-    if fd.SocketHandle notin p.selector:
+    var newEvents = {Event.Read}
+    withData(p.selector, fd.SocketHandle, adata) do:
+      adata.readList.add(cb)
+      newEvents.incl(Event.Read)
+      if len(adata.writeList) != 0: newEvents.incl(Event.Write)
+    do:
       raise newException(ValueError, "File descriptor not registered.")
-    p.selector[fd.SocketHandle].data.PData.readCBs.add(cb)
+    p.selector.updateHandle(fd.SocketHandle, newEvents)
-    update(fd, p.selector[fd.SocketHandle].events + {EvRead})
 
   proc addWrite*(fd: AsyncFD, cb: Callback) =
     let p = getGlobalDispatcher()
-    if fd.SocketHandle notin p.selector:
+    var newEvents = {Event.Write}
+    withData(p.selector, fd.SocketHandle, adata) do:
+      adata.writeList.add(cb)
+      newEvents.incl(Event.Write)
+      if len(adata.readList) != 0: newEvents.incl(Event.Read)
+    do:
       raise newException(ValueError, "File descriptor not registered.")
-    p.selector[fd.SocketHandle].data.PData.writeCBs.add(cb)
+    p.selector.updateHandle(fd.SocketHandle, newEvents)
-    update(fd, p.selector[fd.SocketHandle].events + {EvWrite})
-
-  template processCallbacks(callbacks: untyped) =
-    # Callback may add items to ``callbacks`` which causes issues if
-    # we are iterating over it at the same time. We therefore
-    # make a copy to iterate over.
-    let currentCBs = callbacks
-    callbacks = @[]
-    # Using another sequence because callbacks themselves can add
-    # other callbacks.
-    var newCBs: seq[Callback] = @[]
-    for cb in currentCBs:
-      if newCBs.len > 0:
-        # A callback has already returned with EAGAIN, don't call any
-        # others until next `poll`.
-        newCBs.add(cb)
-      else:
-        if not cb(data.fd):
-          # Callback wants to be called again.
-          newCBs.add(cb)
-    callbacks = newCBs & callbacks
 
   proc hasPendingOperations*(): bool =
     let p = getGlobalDispatcher()
-    p.selector.len != 0 or p.timers.len != 0 or p.callbacks.len != 0
+    not p.selector.isEmpty() or p.timers.len != 0 or p.callbacks.len != 0
+
+  template processBasicCallbacks(ident, rwlist: untyped) =
+    # Process pending descriptor and AsyncEvent callbacks.
+    #
+    # Invoke every callback stored in `rwlist`, until one
+    # returns `false` (which means callback wants to stay
+    # alive). In such case all remaining callbacks will be added
+    # to `rwlist` again, in the order they have been inserted.
+    #
+    # `rwlist` associated with file descriptor MUST BE emptied before
+    # dispatching callback (See https://github.com/nim-lang/Nim/issues/5128),
+    # or it can be possible to fall into endless cycle.
+    var curList: seq[Callback]
+
+    withData(p.selector, ident, adata) do:
+      shallowCopy(curList, adata.rwlist)
+      adata.rwlist = newSeqOfCap[Callback](InitCallbackListSize)
+
+    let newLength = max(len(curList), InitCallbackListSize)
+    var newList = newSeqOfCap[Callback](newLength)
+
+    for cb in curList:
+      if len(newList) > 0:
+        # A callback has already returned with EAGAIN, don't call any others
+        # until next `poll`.
+        newList.add(cb)
+      else:
+        if not cb(fd.AsyncFD):
+          # Callback wants to be called again.
+          newList.add(cb)
+
+    withData(p.selector, ident, adata) do:
+      # descriptor still present in queue.
+      adata.rwlist = newList & adata.rwlist
+      rLength = len(adata.readList)
+      wLength = len(adata.writeList)
+    do:
+      # descriptor was unregistered in callback via `unregister()`.
+      rLength = -1
+      wLength = -1
+
+  template processCustomCallbacks(ident: untyped) =
+    # Process pending custom event callbacks. Custom events are
+    # {Event.Timer, Event.Signal, Event.Process, Event.Vnode}.
+    # There can be only one callback registered with one descriptor,
+    # so there is no need to iterate over list.
+    var curList: seq[Callback]
+
+    withData(p.selector, ident, adata) do:
+      shallowCopy(curList, adata.readList)
+      adata.readList = newSeqOfCap[Callback](InitCallbackListSize)
+
+    let newLength = len(curList)
+    var newList = newSeqOfCap[Callback](newLength)
+
+    var cb = curList[0]
+    if not cb(fd.AsyncFD):
+      newList.add(cb)
+
+    withData(p.selector, ident, adata) do:
+      # descriptor still present in queue.
+      adata.readList = newList & adata.readList
+      if len(adata.readList) == 0:
+        # if no callbacks registered with descriptor, unregister it.
+        p.selector.unregister(fd)
+    do:
+      # descriptor was unregistered in callback via `unregister()`.
+      discard
 
   proc poll*(timeout = 500) =
     let p = getGlobalDispatcher()
-    if p.selector.len == 0 and p.timers.len == 0 and p.callbacks.len == 0:
+    when ioselSupportedPlatform:
+      let customSet = {Event.Timer, Event.Signal, Event.Process,
+                       Event.Vnode}
+
+    if p.selector.isEmpty() and p.timers.len == 0 and p.callbacks.len == 0:
       raise newException(ValueError,
         "No handles or timers registered in dispatcher.")
 
-    if p.selector.len > 0:
+    if not p.selector.isEmpty():
-      for info in p.selector.select(p.adjustedTimeout(timeout)):
+      var keys: array[64, ReadyKey]
-        let data = PData(info.key.data)
+      var count = p.selector.selectInto(p.adjustedTimeout(timeout), keys)
-        assert data.fd == info.key.fd.AsyncFD
+      for i in 0..<count:
-        #echo("In poll ", data.fd.cint)
+        var custom = false
-        # There may be EvError here, but we handle them in callbacks,
+        let fd = keys[i].fd
-        # so that exceptions can be raised from `send(...)` and
+        let events = keys[i].events
-        # `recv(...)` routines.
+        var rLength = 0 # len(data.readList) after callback
+        var wLength = 0 # len(data.writeList) after callback
 
-        if EvRead in info.events or info.events == {EvError}:
+        if Event.Read in events or events == {Event.Error}:
-          processCallbacks(data.readCBs)
+          processBasicCallbacks(fd, readList)
 
-        if EvWrite in info.events or info.events == {EvError}:
+        if Event.Write in events or events == {Event.Error}:
-          processCallbacks(data.writeCBs)
+          processBasicCallbacks(fd, writeList)
 
-        if info.key in p.selector:
+        if Event.User in events or events == {Event.Error}:
-          var newEvents: set[Event]
+          processBasicCallbacks(fd, readList)
-          if data.readCBs.len != 0: newEvents = {EvRead}
+          custom = true
-          if data.writeCBs.len != 0: newEvents = newEvents + {EvWrite}
+          if rLength == 0:
-          if newEvents != info.key.events:
+            p.selector.unregister(fd)
-            update(data.fd, newEvents)
+
-        else:
+        when ioselSupportedPlatform:
-          # FD no longer a part of the selector. Likely been closed
+          if (customSet * events) != {}:
-          # (e.g. socket disconnected).
+            custom = true
-          discard
+            processCustomCallbacks(fd)
+
+        # because state `data` can be modified in callback we need to update
+        # descriptor events with currently registered callbacks.
+        if not custom:
+          var newEvents: set[Event] = {}
+          if rLength != -1 and wLength != -1:
+            if rLength > 0: incl(newEvents, Event.Read)
+            if wLength > 0: incl(newEvents, Event.Write)
+            p.selector.updateHandle(SocketHandle(fd), newEvents)
 
     # Timer processing.
     processTimers(p)
@@ -1075,7 +1283,7 @@ else:
     return retFuture
 
   proc recvInto*(socket: AsyncFD, buf: pointer, size: int,
-                  flags = {SocketFlag.SafeDisconn}): Future[int] =
+                 flags = {SocketFlag.SafeDisconn}): Future[int] =
     var retFuture = newFuture[int]("recvInto")
 
     proc cb(sock: AsyncFD): bool =
@@ -1216,6 +1424,55 @@ else:
     addRead(socket, cb)
     return retFuture
 
+  when ioselSupportedPlatform:
+
+    proc addTimer*(timeout: int, oneshot: bool, cb: Callback) =
+      ## Start watching for timeout expiration, and then call the
+      ## callback ``cb``.
+      ## ``timeout`` - time in milliseconds,
+      ## ``oneshot`` - if ``true`` only one event will be dispatched,
+      ## if ``false`` continuous events every ``timeout`` milliseconds.
+      let p = getGlobalDispatcher()
+      var data = newAsyncData()
+      data.readList.add(cb)
+      p.selector.registerTimer(timeout, oneshot, data)
+
+    proc addSignal*(signal: int, cb: Callback) =
+      ## Start watching signal ``signal``, and when signal appears, call the
+      ## callback ``cb``.
+      let p = getGlobalDispatcher()
+      var data = newAsyncData()
+      data.readList.add(cb)
+      p.selector.registerSignal(signal, data)
+
+    proc addProcess*(pid: int, cb: Callback) =
+      ## Start watching for process exit with pid ``pid``, and then call
+      ## the callback ``cb``.
+      let p = getGlobalDispatcher()
+      var data = newAsyncData()
+      data.readList.add(cb)
+      p.selector.registerProcess(pid, data)
+
+  proc newAsyncEvent*(): AsyncEvent =
+    ## Creates new ``AsyncEvent``.
+    result = AsyncEvent(newSelectEvent())
+
+  proc trigger*(ev: AsyncEvent) =
+    ## Sets new ``AsyncEvent`` to signaled state.
+    trigger(SelectEvent(ev))
+
+  proc close*(ev: AsyncEvent) =
+    ## Closes ``AsyncEvent``
+    close(SelectEvent(ev))
+
+  proc addEvent*(ev: AsyncEvent, cb: Callback) =
+    ## Start watching for event ``ev``, and call callback ``cb``, when
+    ## ev will be set to signaled state.
+    let p = getGlobalDispatcher()
+    var data = newAsyncData()
+    data.readList.add(cb)
+    p.selector.registerEvent(SelectEvent(ev), data)
+
 # Common procedures between current and upcoming asyncdispatch
 include includes.asynccommon
 
@@ -1269,7 +1526,7 @@ proc send*(socket: AsyncFD, data: string,
 
   var copiedData = data
   GC_ref(copiedData) # we need to protect data until send operation is completed
-               # or failed.
+                     # or failed.
 
   let sendFut = socket.send(addr copiedData[0], data.len, flags)
   sendFut.callback =
@@ -1317,7 +1574,7 @@ proc recvLine*(socket: AsyncFD): Future[string] {.async, deprecated.} =
   ##
   ## **Deprecated since version 0.15.0**: Use ``asyncnet.recvLine()`` instead.
 
-  template addNLIfEmpty(): untyped =
+  template addNLIfEmpty(): typed =
     if result.len == 0:
       result.add("\c\L")
 
@@ -1353,3 +1610,5 @@ proc waitFor*[T](fut: Future[T]): T =
     poll()
 
   fut.read
+
+{.deprecated: [setEvent: trigger].}

lib/pure/ioselectors.nim

@@ -1,294 +0,0 @@
-#
-#
-#            Nim's Runtime Library
-#        (c) Copyright 2016 Eugene Kabanov
-#
-#    See the file "copying.txt", included in this
-#    distribution, for details about the copyright.
-#
-
-## This module allows high-level and efficient I/O multiplexing.
-##
-## Supported OS primitives: ``epoll``, ``kqueue``, ``poll`` and
-## Windows ``select``.
-##
-## To use threadsafe version of this module, it needs to be compiled
-## with both ``-d:threadsafe`` and ``--threads:on`` options.
-##
-## Supported features: files, sockets, pipes, timers, processes, signals
-## and user events.
-##
-## Fully supported OS: MacOSX, FreeBSD, OpenBSD, NetBSD, Linux (except
-## for Android).
-##
-## Partially supported OS: Windows (only sockets and user events),
-## Solaris (files, sockets, handles and user events).
-## Android (files, sockets, handles and user events).
-##
-## TODO: ``/dev/poll``, ``event ports`` and filesystem events.
-
-import os
-
-const hasThreadSupport = compileOption("threads") and defined(threadsafe)
-
-const ioselSupportedPlatform* = defined(macosx) or defined(freebsd) or
-                                defined(netbsd) or defined(openbsd) or
-                                defined(dragonfly) or
-                                (defined(linux) and not defined(android))
-  ## This constant is used to determine whether the destination platform is
-  ## fully supported by ``ioselectors`` module.
-
-const bsdPlatform = defined(macosx) or defined(freebsd) or
-                    defined(netbsd) or defined(openbsd) or
-                    defined(dragonfly)
-
-when defined(nimdoc):
-  type SocketHandle = int
-  type
-    Selector*[T] = ref object
-      ## An object which holds descriptors to be checked for read/write status
-
-    Event* {.pure.} = enum
-      ## An enum which hold event types
-      Read,        ## Descriptor is available for read
-      Write,       ## Descriptor is available for write
-      Timer,       ## Timer descriptor is completed
-      Signal,      ## Signal is raised
-      Process,     ## Process is finished
-      Vnode,       ## BSD specific file change happens
-      User,        ## User event is raised
-      Error,       ## Error happens while waiting, for descriptor
-      VnodeWrite,  ## NOTE_WRITE (BSD specific, write to file occurred)
-      VnodeDelete, ## NOTE_DELETE (BSD specific, unlink of file occurred)
-      VnodeExtend, ## NOTE_EXTEND (BSD specific, file extended)
-      VnodeAttrib, ## NOTE_ATTRIB (BSD specific, file attributes changed)
-      VnodeLink,   ## NOTE_LINK (BSD specific, file link count changed)
-      VnodeRename, ## NOTE_RENAME (BSD specific, file renamed)
-      VnodeRevoke  ## NOTE_REVOKE (BSD specific, file revoke occurred)
-
-    ReadyKey* = object
-      ## An object which holds result for descriptor
-      fd* : int ## file/socket descriptor
-      events*: set[Event] ## set of events
-
-    SelectEvent* = object
-      ## An object which holds user defined event
-
-  proc newSelector*[T](): Selector[T] =
-    ## Creates a new selector
-
-  proc close*[T](s: Selector[T]) =
-    ## Closes selector
-
-  proc registerHandle*[T](s: Selector[T], fd: SocketHandle, events: set[Event],
-                          data: T) =
-    ## Registers file/socket descriptor ``fd`` to selector ``s``
-    ## with events set in ``events``. The ``data`` is application-defined
-    ## data, which to be passed when event happens.
-
-  proc updateHandle*[T](s: Selector[T], fd: SocketHandle, events: set[Event]) =
-    ## Update file/socket descriptor ``fd``, registered in selector
-    ## ``s`` with new events set ``event``.
-
-  proc registerTimer*[T](s: Selector[T], timeout: int, oneshot: bool,
-                         data: T): int {.discardable.} =
-    ## Registers timer notification with ``timeout`` in milliseconds
-    ## to selector ``s``.
-    ## If ``oneshot`` is ``true`` timer will be notified only once.
-    ## Set ``oneshot`` to ``false`` if your want periodic notifications.
-    ## The ``data`` is application-defined data, which to be passed, when
-    ## time limit expired.
-
-  proc registerSignal*[T](s: Selector[T], signal: int,
-                          data: T): int {.discardable.} =
-    ## Registers Unix signal notification with ``signal`` to selector
-    ## ``s``. The ``data`` is application-defined data, which to be
-    ## passed, when signal raises.
-    ##
-    ## This function is not supported for ``Windows``.
-
-  proc registerProcess*[T](s: Selector[T], pid: int,
-                           data: T): int {.discardable.} =
-    ## Registers process id (pid) notification when process has
-    ## exited to selector ``s``.
-    ## The ``data`` is application-defined data, which to be passed, when
-    ## process with ``pid`` has exited.
-
-  proc registerEvent*[T](s: Selector[T], ev: SelectEvent, data: T) =
-    ## Registers selector event ``ev`` to selector ``s``.
-    ## ``data`` application-defined data, which to be passed, when
-    ## ``ev`` happens.
-
-  proc registerVnode*[T](s: Selector[T], fd: cint, events: set[Event],
-                         data: T) =
-    ## Registers selector BSD/MacOSX specific vnode events for file
-    ## descriptor ``fd`` and events ``events``.
-    ## ``data`` application-defined data, which to be passed, when
-    ## vnode event happens.
-    ##
-    ## This function is supported only by BSD and MacOSX.
-
-  proc newSelectEvent*(): SelectEvent =
-    ## Creates new event ``SelectEvent``.
-
-  proc setEvent*(ev: SelectEvent) =
-    ## Trigger event ``ev``.
-
-  proc close*(ev: SelectEvent) =
-    ## Closes selector event ``ev``.
-
-  proc unregister*[T](s: Selector[T], ev: SelectEvent) =
-    ## Unregisters event ``ev`` from selector ``s``.
-
-  proc unregister*[T](s: Selector[T], fd: int|SocketHandle|cint) =
-    ## Unregisters file/socket descriptor ``fd`` from selector ``s``.
-
-  proc selectInto*[T](s: Selector[T], timeout: int,
-                      results: var openarray[ReadyKey]): int =
-    ## Process call waiting for events registered in selector ``s``.
-    ## The ``timeout`` argument specifies the minimum number of milliseconds
-    ## the function will be blocked, if no events are not ready. Specifying a
-    ## timeout of ``-1`` causes function to block indefinitely.
-    ## All available events will be stored in ``results`` array.
-    ##
-    ## Function returns number of triggered events.
-
-  proc select*[T](s: Selector[T], timeout: int): seq[ReadyKey] =
-    ## Process call waiting for events registered in selector ``s``.
-    ## The ``timeout`` argument specifies the minimum number of milliseconds
-    ## the function will be blocked, if no events are not ready. Specifying a
-    ## timeout of -1 causes function to block indefinitely.
-    ##
-    ## Function returns sequence of triggered events.
-
-  proc getData*[T](s: Selector[T], fd: SocketHandle|int): T =
-    ## Retrieves application-defined ``data`` associated with descriptor ``fd``.
-    ## If specified descriptor ``fd`` is not registered, empty/default value
-    ## will be returned.
-
-  proc setData*[T](s: Selector[T], fd: SocketHandle|int, data: var T): bool =
-    ## Associate application-defined ``data`` with descriptor ``fd``.
-    ##
-    ## Returns ``true``, if data was succesfully updated, ``false`` otherwise.
-
-  template isEmpty*[T](s: Selector[T]): bool =
-    ## Returns ``true``, if there no registered events or descriptors
-    ## in selector.
-
-  template withData*[T](s: Selector[T], fd: SocketHandle|int, value,
-                        body: untyped) =
-    ## Retrieves the application-data assigned with descriptor ``fd``
-    ## to ``value``. This ``value`` can be modified in the scope of
-    ## the ``withData`` call.
-    ##
-    ## .. code-block:: nim
-    ##
-    ##   s.withData(fd, value) do:
-    ##     # block is executed only if ``fd`` registered in selector ``s``
-    ##     value.uid = 1000
-    ##
-
-  template withData*[T](s: Selector[T], fd: SocketHandle|int, value,
-                        body1, body2: untyped) =
-    ## Retrieves the application-data assigned with descriptor ``fd``
-    ## to ``value``. This ``value`` can be modified in the scope of
-    ## the ``withData`` call.
-    ##
-    ## .. code-block:: nim
-    ##
-    ##   s.withData(fd, value) do:
-    ##     # block is executed only if ``fd`` registered in selector ``s``.
-    ##     value.uid = 1000
-    ##   do:
-    ##     # block is executed if ``fd`` not registered in selector ``s``.
-    ##     raise
-    ##
-
-else:
-  when hasThreadSupport:
-    import locks
-
-    type
-      SharedArray[T] = UncheckedArray[T]
-
-    proc allocSharedArray[T](nsize: int): ptr SharedArray[T] =
-      result = cast[ptr SharedArray[T]](allocShared0(sizeof(T) * nsize))
-
-    proc deallocSharedArray[T](sa: ptr SharedArray[T]) =
-      deallocShared(cast[pointer](sa))
-  type
-    Event* {.pure.} = enum
-      Read, Write, Timer, Signal, Process, Vnode, User, Error, Oneshot,
-      Finished, VnodeWrite, VnodeDelete, VnodeExtend, VnodeAttrib, VnodeLink,
-      VnodeRename, VnodeRevoke
-
-  type
-    IOSelectorsException* = object of Exception
-
-    ReadyKey* = object
-      fd* : int
-      events*: set[Event]
-
-    SelectorKey[T] = object
-      ident: int
-      events: set[Event]
-      param: int
-      data: T
-
-  proc raiseIOSelectorsError[T](message: T) =
-    var msg = ""
-    when T is string:
-      msg.add(message)
-    elif T is OSErrorCode:
-      msg.add(osErrorMsg(message) & " (code: " & $int(message) & ")")
-    else:
-      msg.add("Internal Error\n")
-    var err = newException(IOSelectorsException, msg)
-    raise err
-
-  when not defined(windows):
-    import posix
-
-    proc setNonBlocking(fd: cint) {.inline.} =
-      var x = fcntl(fd, F_GETFL, 0)
-      if x == -1:
-        raiseIOSelectorsError(osLastError())
-      else:
-        var mode = x or O_NONBLOCK
-        if fcntl(fd, F_SETFL, mode) == -1:
-          raiseIOSelectorsError(osLastError())
-
-    template setKey(s, pident, pevents, pparam, pdata: untyped) =
-      var skey = addr(s.fds[pident])
-      skey.ident = pident
-      skey.events = pevents
-      skey.param = pparam
-      skey.data = data
-
-  when ioselSupportedPlatform:
-    template blockSignals(newmask: var Sigset, oldmask: var Sigset) =
-      when hasThreadSupport:
-        if posix.pthread_sigmask(SIG_BLOCK, newmask, oldmask) == -1:
-          raiseIOSelectorsError(osLastError())
-      else:
-        if posix.sigprocmask(SIG_BLOCK, newmask, oldmask) == -1:
-          raiseIOSelectorsError(osLastError())
-
-    template unblockSignals(newmask: var Sigset, oldmask: var Sigset) =
-      when hasThreadSupport:
-        if posix.pthread_sigmask(SIG_UNBLOCK, newmask, oldmask) == -1:
-          raiseIOSelectorsError(osLastError())
-      else:
-        if posix.sigprocmask(SIG_UNBLOCK, newmask, oldmask) == -1:
-          raiseIOSelectorsError(osLastError())
-
-  when defined(linux):
-    include ioselects/ioselectors_epoll
-  elif bsdPlatform:
-    include ioselects/ioselectors_kqueue
-  elif defined(windows):
-    include ioselects/ioselectors_select
-  elif defined(solaris):
-    include ioselects/ioselectors_poll # need to replace it with event ports
-  else:
-    include ioselects/ioselectors_poll

lib/pure/ioselects/ioselectors_epoll.nim

@@ -9,7 +9,7 @@
 
 # This module implements Linux epoll().
 
-import posix, times
+import posix, times, epoll
 
 # Maximum number of events that can be returned
 const MAX_EPOLL_EVENTS = 64
@@ -36,35 +36,6 @@ when not defined(android):
       ssi_addr*: uint64
       pad* {.importc: "__pad".}: array[0..47, uint8]
 
-type
-  eventFdData {.importc: "eventfd_t",
-                header: "<sys/eventfd.h>", pure, final.} = uint64
-  epoll_data {.importc: "union epoll_data", header: "<sys/epoll.h>",
-               pure, final.} = object
-    u64 {.importc: "u64".}: uint64
-  epoll_event {.importc: "struct epoll_event",
-                header: "<sys/epoll.h>", pure, final.} = object
-    events: uint32 # Epoll events
-    data: epoll_data # User data variable
-
-const
-  EPOLL_CTL_ADD = 1          # Add a file descriptor to the interface.
-  EPOLL_CTL_DEL = 2          # Remove a file descriptor from the interface.
-  EPOLL_CTL_MOD = 3          # Change file descriptor epoll_event structure.
-  EPOLLIN = 0x00000001
-  EPOLLOUT = 0x00000004
-  EPOLLERR = 0x00000008
-  EPOLLHUP = 0x00000010
-  EPOLLRDHUP = 0x00002000
-  EPOLLONESHOT = 1 shl 30
-
-proc epoll_create(size: cint): cint
-     {.importc: "epoll_create", header: "<sys/epoll.h>".}
-proc epoll_ctl(epfd: cint; op: cint; fd: cint; event: ptr epoll_event): cint
-     {.importc: "epoll_ctl", header: "<sys/epoll.h>".}
-proc epoll_wait(epfd: cint; events: ptr epoll_event; maxevents: cint;
-                 timeout: cint): cint
-     {.importc: "epoll_wait", header: "<sys/epoll.h>".}
 proc timerfd_create(clock_id: ClockId, flags: cint): cint
      {.cdecl, importc: "timerfd_create", header: "<sys/timerfd.h>".}
 proc timerfd_settime(ufd: cint, flags: cint,
@@ -80,26 +51,26 @@ when not defined(android):
 var RLIMIT_NOFILE {.importc: "RLIMIT_NOFILE",
                     header: "<sys/resource.h>".}: cint
 type
-  rlimit {.importc: "struct rlimit",
+  RLimit {.importc: "struct rlimit",
            header: "<sys/resource.h>", pure, final.} = object
     rlim_cur: int
     rlim_max: int
-proc getrlimit(resource: cint, rlp: var rlimit): cint
+proc getrlimit(resource: cint, rlp: var RLimit): cint
      {.importc: "getrlimit",header: "<sys/resource.h>".}
 
 when hasThreadSupport:
   type
     SelectorImpl[T] = object
-      epollFD : cint
+      epollFD: cint
-      maxFD : int
+      maxFD: int
       fds: ptr SharedArray[SelectorKey[T]]
       count: int
     Selector*[T] = ptr SelectorImpl[T]
 else:
   type
     SelectorImpl[T] = object
-      epollFD : cint
+      epollFD: cint
-      maxFD : int
+      maxFD: int
       fds: seq[SelectorKey[T]]
       count: int
     Selector*[T] = ref SelectorImpl[T]
@@ -109,7 +80,8 @@ type
   SelectEvent* = ptr SelectEventImpl
 
 proc newSelector*[T](): Selector[T] =
-  var a = rlimit()
+  # Retrieve the maximum fd count (for current OS) via getrlimit()
+  var a = RLimit()
   if getrlimit(RLIMIT_NOFILE, a) != 0:
     raiseOsError(osLastError())
   var maxFD = int(a.rlim_max)
@@ -152,8 +124,8 @@ proc newSelectEvent*(): SelectEvent =
   result = cast[SelectEvent](allocShared0(sizeof(SelectEventImpl)))
   result.efd = fdci
 
-proc setEvent*(ev: SelectEvent) =
+proc trigger*(ev: SelectEvent) =
-  var data : uint64 = 1
+  var data: uint64 = 1
   if posix.write(ev.efd, addr data, sizeof(uint64)) == -1:
     raiseIOSelectorsError(osLastError())
 
@@ -164,6 +136,8 @@ proc close*(ev: SelectEvent) =
     raiseIOSelectorsError(osLastError())
 
 template checkFd(s, f) =
+  # TODO: I don't see how this can ever happen. You won't be able to create an
+  # FD if there is too many. -- DP
   if f >= s.maxFD:
     raiseIOSelectorsError("Maximum number of descriptors is exhausted!")
 
@@ -171,10 +145,10 @@ proc registerHandle*[T](s: Selector[T], fd: SocketHandle,
                         events: set[Event], data: T) =
   let fdi = int(fd)
   s.checkFd(fdi)
-  doAssert(s.fds[fdi].ident == 0)
+  doAssert(s.fds[fdi].ident == 0, "Descriptor $# already registered" % $fdi)
   s.setKey(fdi, events, 0, data)
   if events != {}:
-    var epv = epoll_event(events: EPOLLRDHUP)
+    var epv = EpollEvent(events: EPOLLRDHUP)
     epv.data.u64 = fdi.uint
     if Event.Read in events: epv.events = epv.events or EPOLLIN
     if Event.Write in events: epv.events = epv.events or EPOLLOUT
@@ -189,10 +163,10 @@ proc updateHandle*[T](s: Selector[T], fd: SocketHandle, events: set[Event]) =
   s.checkFd(fdi)
   var pkey = addr(s.fds[fdi])
   doAssert(pkey.ident != 0,
-           "Descriptor [" & $fdi & "] is not registered in the queue!")
+           "Descriptor $# is not registered in the selector!" % $fdi)
   doAssert(pkey.events * maskEvents == {})
   if pkey.events != events:
-    var epv = epoll_event(events: EPOLLRDHUP)
+    var epv = EpollEvent(events: EPOLLRDHUP)
     epv.data.u64 = fdi.uint
 
     if Event.Read in events: epv.events = epv.events or EPOLLIN
@@ -217,24 +191,25 @@ proc unregister*[T](s: Selector[T], fd: int|SocketHandle) =
   s.checkFd(fdi)
   var pkey = addr(s.fds[fdi])
   doAssert(pkey.ident != 0,
-           "Descriptor [" & $fdi & "] is not registered in the queue!")
+           "Descriptor $# is not registered in the selector!" % $fdi)
   if pkey.events != {}:
     when not defined(android):
       if pkey.events * {Event.Read, Event.Write} != {}:
-        var epv = epoll_event()
+        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:
           raiseIOSelectorsError(osLastError())
         dec(s.count)
       elif Event.Timer in pkey.events:
         if Event.Finished notin pkey.events:
-          var epv = epoll_event()
+          var epv = EpollEvent()
           if epoll_ctl(s.epollFD, EPOLL_CTL_DEL, fdi.cint, addr epv) != 0:
             raiseIOSelectorsError(osLastError())
           dec(s.count)
         if posix.close(cint(fdi)) != 0:
           raiseIOSelectorsError(osLastError())
       elif Event.Signal in pkey.events:
-        var epv = epoll_event()
+        var epv = EpollEvent()
         if epoll_ctl(s.epollFD, EPOLL_CTL_DEL, fdi.cint, addr epv) != 0:
           raiseIOSelectorsError(osLastError())
         var nmask, omask: Sigset
@@ -247,7 +222,7 @@ proc unregister*[T](s: Selector[T], fd: int|SocketHandle) =
           raiseIOSelectorsError(osLastError())
       elif Event.Process in pkey.events:
         if Event.Finished notin pkey.events:
-          var epv = epoll_event()
+          var epv = EpollEvent()
           if epoll_ctl(s.epollFD, EPOLL_CTL_DEL, fdi.cint, addr epv) != 0:
             raiseIOSelectorsError(osLastError())
           var nmask, omask: Sigset
@@ -260,13 +235,13 @@ proc unregister*[T](s: Selector[T], fd: int|SocketHandle) =
           raiseIOSelectorsError(osLastError())
     else:
       if pkey.events * {Event.Read, Event.Write} != {}:
-        var epv = epoll_event()
+        var epv = EpollEvent()
         if epoll_ctl(s.epollFD, EPOLL_CTL_DEL, fdi.cint, addr epv) != 0:
           raiseIOSelectorsError(osLastError())
         dec(s.count)
       elif Event.Timer in pkey.events:
         if Event.Finished notin pkey.events:
-          var epv = epoll_event()
+          var epv = EpollEvent()
           if epoll_ctl(s.epollFD, EPOLL_CTL_DEL, fdi.cint, addr epv) != 0:
             raiseIOSelectorsError(osLastError())
           dec(s.count)
@@ -280,7 +255,7 @@ proc unregister*[T](s: Selector[T], ev: SelectEvent) =
   var pkey = addr(s.fds[fdi])
   doAssert(pkey.ident != 0, "Event is not registered in the queue!")
   doAssert(Event.User in pkey.events)
-  var epv = epoll_event()
+  var epv = EpollEvent()
   if epoll_ctl(s.epollFD, EPOLL_CTL_DEL, fdi.cint, addr epv) != 0:
     raiseIOSelectorsError(osLastError())
   dec(s.count)
@@ -300,7 +275,7 @@ proc registerTimer*[T](s: Selector[T], timeout: int, oneshot: bool,
   doAssert(s.fds[fdi].ident == 0)
 
   var events = {Event.Timer}
-  var epv = epoll_event(events: EPOLLIN or EPOLLRDHUP)
+  var epv = EpollEvent(events: EPOLLIN or EPOLLRDHUP)
   epv.data.u64 = fdi.uint
   if oneshot:
     new_ts.it_interval.tv_sec = 0.Time
@@ -343,7 +318,7 @@ when not defined(android):
     s.checkFd(fdi)
     doAssert(s.fds[fdi].ident == 0)
 
-    var epv = epoll_event(events: EPOLLIN or EPOLLRDHUP)
+    var epv = EpollEvent(events: EPOLLIN or EPOLLRDHUP)
     epv.data.u64 = fdi.uint
     if epoll_ctl(s.epollFD, EPOLL_CTL_ADD, fdi.cint, addr epv) != 0:
       raiseIOSelectorsError(osLastError())
@@ -370,7 +345,7 @@ when not defined(android):
     s.checkFd(fdi)
     doAssert(s.fds[fdi].ident == 0)
 
-    var epv = epoll_event(events: EPOLLIN or EPOLLRDHUP)
+    var epv = EpollEvent(events: EPOLLIN or EPOLLRDHUP)
     epv.data.u64 = fdi.uint
     epv.events = EPOLLIN or EPOLLRDHUP
     if epoll_ctl(s.epollFD, EPOLL_CTL_ADD, fdi.cint, addr epv) != 0:
@@ -383,7 +358,7 @@ proc registerEvent*[T](s: Selector[T], ev: SelectEvent, data: T) =
   let fdi = int(ev.efd)
   doAssert(s.fds[fdi].ident == 0, "Event is already registered in the queue!")
   s.setKey(fdi, {Event.User}, 0, data)
-  var epv = epoll_event(events: EPOLLIN or EPOLLRDHUP)
+  var epv = EpollEvent(events: EPOLLIN or EPOLLRDHUP)
   epv.data.u64 = ev.efd.uint
   if epoll_ctl(s.epollFD, EPOLL_CTL_ADD, ev.efd, addr epv) != 0:
     raiseIOSelectorsError(osLastError())
@@ -392,7 +367,7 @@ proc registerEvent*[T](s: Selector[T], ev: SelectEvent, data: T) =
 proc selectInto*[T](s: Selector[T], timeout: int,
                     results: var openarray[ReadyKey]): int =
   var
-    resTable: array[MAX_EPOLL_EVENTS, epoll_event]
+    resTable: array[MAX_EPOLL_EVENTS, EpollEvent]
     maxres = MAX_EPOLL_EVENTS
     i, k: int
 
@@ -482,7 +457,7 @@ proc selectInto*[T](s: Selector[T], timeout: int,
             rkey.events.incl(Event.User)
 
       if Event.Oneshot in pkey.events:
-        var epv = epoll_event()
+        var epv = EpollEvent()
         if epoll_ctl(s.epollFD, EPOLL_CTL_DEL, cint(fdi), addr epv) != 0:
           raiseIOSelectorsError(osLastError())
         # we will not clear key until it will be unregistered, so
@@ -505,16 +480,19 @@ proc select*[T](s: Selector[T], timeout: int): seq[ReadyKey] =
 template isEmpty*[T](s: Selector[T]): bool =
   (s.count == 0)
 
-proc getData*[T](s: Selector[T], fd: SocketHandle|int): T =
+proc contains*[T](s: Selector[T], fd: SocketHandle|int): bool {.inline.} =
+  return s.fds[fd].ident != 0
+
+proc getData*[T](s: Selector[T], fd: SocketHandle|int): var T =
   let fdi = int(fd)
   s.checkFd(fdi)
-  if s.fds[fdi].ident != 0:
+  if fdi in s:
     result = s.fds[fdi].data
 
 proc setData*[T](s: Selector[T], fd: SocketHandle|int, data: T): bool =
   let fdi = int(fd)
   s.checkFd(fdi)
-  if s.fds[fdi].ident != 0:
+  if fdi in s:
     s.fds[fdi].data = data
     result = true
 
@@ -523,8 +501,8 @@ template withData*[T](s: Selector[T], fd: SocketHandle|int, value,
   mixin checkFd
   let fdi = int(fd)
   s.checkFd(fdi)
-  if s.fds[fdi].ident != 0:
+  if fdi in s:
-    var value = addr(s.fds[fdi].data)
+    var value = addr(s.getData(fdi))
     body
 
 template withData*[T](s: Selector[T], fd: SocketHandle|int, value, body1,
@@ -532,8 +510,8 @@ template withData*[T](s: Selector[T], fd: SocketHandle|int, value, body1,
   mixin checkFd
   let fdi = int(fd)
   s.checkFd(fdi)
-  if s.fds[fdi].ident != 0:
+  if fdi in s:
-    var value = addr(s.fds[fdi].data)
+    var value = addr(s.getData(fdi))
     body1
   else:
     body2

lib/pure/ioselects/ioselectors_kqueue.nim

@@ -144,7 +144,7 @@ proc newSelectEvent*(): SelectEvent =
   result.rfd = fds[0]
   result.wfd = fds[1]
 
-proc setEvent*(ev: SelectEvent) =
+proc trigger*(ev: SelectEvent) =
   var data: uint64 = 1
   if posix.write(ev.wfd, addr data, sizeof(uint64)) != sizeof(uint64):
     raiseIOSelectorsError(osLastError())
@@ -243,7 +243,7 @@ proc updateHandle*[T](s: Selector[T], fd: SocketHandle,
   s.checkFd(fdi)
   var pkey = addr(s.fds[fdi])
   doAssert(pkey.ident != 0,
-           "Descriptor [" & $fdi & "] is not registered in the queue!")
+           "Descriptor $# is not registered in the queue!" % $fdi)
   doAssert(pkey.events * maskEvents == {})
 
   if pkey.events != events:
@@ -584,16 +584,19 @@ proc select*[T](s: Selector[T], timeout: int): seq[ReadyKey] =
 template isEmpty*[T](s: Selector[T]): bool =
   (s.count == 0)
 
-proc getData*[T](s: Selector[T], fd: SocketHandle|int): T =
+proc contains*[T](s: Selector[T], fd: SocketHandle|int): bool {.inline.} =
+  return s.fds[fd].ident != 0
+
+proc getData*[T](s: Selector[T], fd: SocketHandle|int): var T =
   let fdi = int(fd)
   s.checkFd(fdi)
-  if s.fds[fdi].ident != 0:
+  if fdi in s:
     result = s.fds[fdi].data
 
 proc setData*[T](s: Selector[T], fd: SocketHandle|int, data: T): bool =
   let fdi = int(fd)
   s.checkFd(fdi)
-  if s.fds[fdi].ident != 0:
+  if fdi in s:
     s.fds[fdi].data = data
     result = true
 
@@ -602,8 +605,8 @@ template withData*[T](s: Selector[T], fd: SocketHandle|int, value,
   mixin checkFd
   let fdi = int(fd)
   s.checkFd(fdi)
-  if s.fds[fdi].ident != 0:
+  if fdi in s:
-    var value = addr(s.fds[fdi].data)
+    var value = addr(s.getData(fdi))
     body
 
 template withData*[T](s: Selector[T], fd: SocketHandle|int, value, body1,
@@ -611,8 +614,8 @@ template withData*[T](s: Selector[T], fd: SocketHandle|int, value, body1,
   mixin checkFd
   let fdi = int(fd)
   s.checkFd(fdi)
-  if s.fds[fdi].ident != 0:
+  if fdi in s:
-    var value = addr(s.fds[fdi].data)
+    var value = addr(s.getData(fdi))
     body1
   else:
     body2

lib/pure/ioselects/ioselectors_poll.nim

@@ -208,7 +208,7 @@ proc newSelectEvent*(): SelectEvent =
   result.rfd = fds[0]
   result.wfd = fds[1]
 
-proc setEvent*(ev: SelectEvent) =
+proc trigger*(ev: SelectEvent) =
   var data: uint64 = 1
   if posix.write(ev.wfd, addr data, sizeof(uint64)) != sizeof(uint64):
     raiseIOSelectorsError(osLastError())
@@ -279,16 +279,19 @@ proc select*[T](s: Selector[T], timeout: int): seq[ReadyKey] =
 template isEmpty*[T](s: Selector[T]): bool =
   (s.count == 0)
 
-proc getData*[T](s: Selector[T], fd: SocketHandle|int): T =
+proc contains*[T](s: Selector[T], fd: SocketHandle|int): bool {.inline.} =
+  return s.fds[fd].ident != 0
+
+proc getData*[T](s: Selector[T], fd: SocketHandle|int): var T =
   let fdi = int(fd)
   s.checkFd(fdi)
-  if s.fds[fdi].ident != 0:
+  if fdi in s:
     result = s.fds[fdi].data
 
 proc setData*[T](s: Selector[T], fd: SocketHandle|int, data: T): bool =
   let fdi = int(fd)
   s.checkFd(fdi)
-  if s.fds[fdi].ident != 0:
+  if fdi in s:
     s.fds[fdi].data = data
     result = true
 
@@ -297,8 +300,8 @@ template withData*[T](s: Selector[T], fd: SocketHandle|int, value,
   mixin checkFd
   let fdi = int(fd)
   s.checkFd(fdi)
-  if s.fds[fdi].ident != 0:
+  if fdi in s:
-    var value = addr(s.fds[fdi].data)
+    var value = addr(s.getData(fdi))
     body
 
 template withData*[T](s: Selector[T], fd: SocketHandle|int, value, body1,
@@ -306,8 +309,8 @@ template withData*[T](s: Selector[T], fd: SocketHandle|int, value, body1,
   mixin checkFd
   let fdi = int(fd)
   s.checkFd(fdi)
-  if s.fds[fdi].ident != 0:
+  if fdi in s:
-    var value = addr(s.fds[fdi].data)
+    var value = addr(s.getData(fdi))
     body1
   else:
     body2

lib/pure/ioselects/ioselectors_select.nim

@@ -154,7 +154,7 @@ when defined(windows):
     result.rsock = rsock
     result.wsock = wsock
 
-  proc setEvent*(ev: SelectEvent) =
+  proc trigger*(ev: SelectEvent) =
     var data: uint64 = 1
     if winlean.send(ev.wsock, cast[pointer](addr data),
                     cint(sizeof(uint64)), 0) != sizeof(uint64):
@@ -178,7 +178,7 @@ else:
     result.rsock = SocketHandle(fds[0])
     result.wsock = SocketHandle(fds[1])
 
-  proc setEvent*(ev: SelectEvent) =
+  proc trigger*(ev: SelectEvent) =
     var data: uint64 = 1
     if posix.write(cint(ev.wsock), addr data, sizeof(uint64)) != sizeof(uint64):
       raiseIOSelectorsError(osLastError())
@@ -379,6 +379,16 @@ proc flush*[T](s: Selector[T]) = discard
 template isEmpty*[T](s: Selector[T]): bool =
   (s.count == 0)
 
+proc contains*[T](s: Selector[T], fd: SocketHandle|int): bool {.inline.} =
+  s.withSelectLock():
+    result = false
+
+    let fdi = int(fd)
+    for i in 0..<FD_SETSIZE:
+      if s.fds[i].ident == fdi:
+        return true
+      inc(i)
+
 when hasThreadSupport:
   template withSelectLock[T](s: Selector[T], body: untyped) =
     acquire(s.lock)
@@ -391,15 +401,12 @@ else:
   template withSelectLock[T](s: Selector[T], body: untyped) =
     body
 
-proc getData*[T](s: Selector[T], fd: SocketHandle|int): T =
+proc getData*[T](s: Selector[T], fd: SocketHandle|int): var T =
   s.withSelectLock():
     let fdi = int(fd)
-    var i = 0
+    for i in 0..<FD_SETSIZE:
-    while i < FD_SETSIZE:
       if s.fds[i].ident == fdi:
-        result = s.fds[i].data
+        return s.fds[i].data
-        break
-      inc(i)
 
 proc setData*[T](s: Selector[T], fd: SocketHandle|int, data: T): bool =
   s.withSelectLock():

lib/pure/selectors.nim

@@ -1,420 +1,311 @@
 #
 #
 #            Nim's Runtime Library
-#        (c) Copyright 2015 Dominik Picheta
+#        (c) Copyright 2016 Eugene Kabanov
 #
 #    See the file "copying.txt", included in this
 #    distribution, for details about the copyright.
 #
 
-# TODO: Docs.
+## This module allows high-level and efficient I/O multiplexing.
+##
+## Supported OS primitives: ``epoll``, ``kqueue``, ``poll`` and
+## Windows ``select``.
+##
+## To use threadsafe version of this module, it needs to be compiled
+## with both ``-d:threadsafe`` and ``--threads:on`` options.
+##
+## Supported features: files, sockets, pipes, timers, processes, signals
+## and user events.
+##
+## Fully supported OS: MacOSX, FreeBSD, OpenBSD, NetBSD, Linux (except
+## for Android).
+##
+## Partially supported OS: Windows (only sockets and user events),
+## Solaris (files, sockets, handles and user events).
+## Android (files, sockets, handles and user events).
+##
+## TODO: ``/dev/poll``, ``event ports`` and filesystem events.
 
-import os, hashes
+import os, strutils, nativesockets
 
-when defined(linux):
+const hasThreadSupport = compileOption("threads") and defined(threadsafe)
-  import posix, epoll
-elif defined(macosx) or defined(freebsd) or defined(openbsd) or defined(netbsd):
-  import posix, kqueue, times
-elif defined(windows):
-  import winlean
-else:
-  import posix
 
-const MultiThreaded = defined(useStdlibThreading)
+const ioselSupportedPlatform* = defined(macosx) or defined(freebsd) or
+                                defined(netbsd) or defined(openbsd) or
+                                defined(dragonfly) or
+                                (defined(linux) and not defined(android))
+  ## This constant is used to determine whether the destination platform is
+  ## fully supported by ``ioselectors`` module.
 
-when MultiThreaded:
+const bsdPlatform = defined(macosx) or defined(freebsd) or
-  import sharedtables
+                    defined(netbsd) or defined(openbsd) or
-
+                    defined(dragonfly)
-  type SelectorData = pointer
-else:
-  import tables
-
-  type SelectorData = RootRef
-
-proc hash*(x: SocketHandle): Hash {.borrow.}
-proc `$`*(x: SocketHandle): string {.borrow.}
-
-type
-  Event* = enum
-    EvRead, EvWrite, EvError
-
-  SelectorKey* = object
-    fd*: SocketHandle
-    events*: set[Event] ## The events which ``fd`` listens for.
-    data*: SelectorData ## User object.
-
-  ReadyInfo* = tuple[key: SelectorKey, events: set[Event]]
 
 when defined(nimdoc):
   type
-    Selector* = ref object
+    Selector*[T] = ref object
-      ## An object which holds file descriptors to be checked for read/write
+      ## An object which holds descriptors to be checked for read/write status
-      ## status.
 
-  proc register*(s: Selector, fd: SocketHandle, events: set[Event],
+    Event* {.pure.} = enum
-                 data: SelectorData): SelectorKey {.discardable.} =
+      ## An enum which hold event types
-    ## Registers file descriptor ``fd`` to selector ``s`` with a set of Event
+      Read,        ## Descriptor is available for read
-    ## ``events``.
+      Write,       ## Descriptor is available for write
+      Timer,       ## Timer descriptor is completed
+      Signal,      ## Signal is raised
+      Process,     ## Process is finished
+      Vnode,       ## BSD specific file change happens
+      User,        ## User event is raised
+      Error,       ## Error happens while waiting, for descriptor
+      VnodeWrite,  ## NOTE_WRITE (BSD specific, write to file occurred)
+      VnodeDelete, ## NOTE_DELETE (BSD specific, unlink of file occurred)
+      VnodeExtend, ## NOTE_EXTEND (BSD specific, file extended)
+      VnodeAttrib, ## NOTE_ATTRIB (BSD specific, file attributes changed)
+      VnodeLink,   ## NOTE_LINK (BSD specific, file link count changed)
+      VnodeRename, ## NOTE_RENAME (BSD specific, file renamed)
+      VnodeRevoke  ## NOTE_REVOKE (BSD specific, file revoke occurred)
 
-  proc update*(s: Selector, fd: SocketHandle,
+    ReadyKey* = object
-               events: set[Event]): SelectorKey {.discardable.} =
+      ## An object which holds result for descriptor
-    ## Updates the events which ``fd`` wants notifications for.
+      fd* : int ## file/socket descriptor
+      events*: set[Event] ## set of events
 
-  proc unregister*(s: Selector, fd: SocketHandle): SelectorKey {.discardable.} =
+    SelectEvent* = object
-    ## Unregisters file descriptor ``fd`` from selector ``s``.
+      ## An object which holds user defined event
 
-  proc close*(s: Selector) =
+  proc newSelector*[T](): Selector[T] =
-    ## Closes the selector
-
-  proc select*(s: Selector, timeout: int): seq[ReadyInfo] =
-    ## The ``events`` field of the returned ``key`` contains the original events
-    ## for which the ``fd`` was bound. This is contrary to the ``events`` field
-    ## of the ``ReadyInfo`` tuple which determines which events are ready
-    ## on the ``fd``.
-
-  proc newSelector*(): Selector =
     ## Creates a new selector
 
-  proc contains*(s: Selector, fd: SocketHandle): bool =
+  proc close*[T](s: Selector[T]) =
+    ## Closes the selector.
+
+  proc registerHandle*[T](s: Selector[T], fd: SocketHandle, events: set[Event],
+                          data: T) =
+    ## Registers file/socket descriptor ``fd`` to selector ``s``
+    ## with events set in ``events``. The ``data`` is application-defined
+    ## data, which will be passed when an event is triggered.
+
+  proc updateHandle*[T](s: Selector[T], fd: SocketHandle, events: set[Event]) =
+    ## Update file/socket descriptor ``fd``, registered in selector
+    ## ``s`` with new events set ``event``.
+
+  proc registerTimer*[T](s: Selector[T], timeout: int, oneshot: bool,
+                         data: T): int {.discardable.} =
+    ## Registers timer notification with ``timeout`` (in milliseconds)
+    ## to selector ``s``.
+    ##
+    ## If ``oneshot`` is ``true``, timer will be notified only once.
+    ##
+    ## Set ``oneshot`` to ``false`` if you want periodic notifications.
+    ##
+    ## The ``data`` is application-defined data, which will be passed, when
+    ## the timer is triggered.
+    ##
+    ## Returns the file descriptor for the registered timer.
+
+  proc registerSignal*[T](s: Selector[T], signal: int,
+                          data: T): int {.discardable.} =
+    ## Registers Unix signal notification with ``signal`` to selector
+    ## ``s``.
+    ##
+    ## The ``data`` is application-defined data, which will be
+    ## passed when signal raises.
+    ##
+    ## Returns the file descriptor for the registered signal.
+    ##
+    ## **Note:** This function is not supported on ``Windows``.
+
+  proc registerProcess*[T](s: Selector[T], pid: int,
+                           data: T): int {.discardable.} =
+    ## Registers a process id (pid) notification (when process has
+    ## exited) in selector ``s``.
+    ##
+    ## The ``data`` is application-defined data, which will be passed when
+    ## process with ``pid`` has exited.
+    ##
+    ## Returns the file descriptor for the registered signal.
+
+  proc registerEvent*[T](s: Selector[T], ev: SelectEvent, data: T) =
+    ## Registers selector event ``ev`` in selector ``s``.
+    ##
+    ## The ``data`` is application-defined data, which will be passed when
+    ## ``ev`` happens.
+
+  proc registerVnode*[T](s: Selector[T], fd: cint, events: set[Event],
+                         data: T) =
+    ## Registers selector BSD/MacOSX specific vnode events for file
+    ## descriptor ``fd`` and events ``events``.
+    ## ``data`` application-defined data, which to be passed, when
+    ## vnode event happens.
+    ##
+    ## **Note:** This function is supported only by BSD and MacOSX.
+
+  proc newSelectEvent*(): SelectEvent =
+    ## Creates a new user-defined event.
+
+  proc trigger*(ev: SelectEvent) =
+    ## Trigger event ``ev``.
+
+  proc close*(ev: SelectEvent) =
+    ## Closes user-defined event ``ev``.
+
+  proc unregister*[T](s: Selector[T], ev: SelectEvent) =
+    ## Unregisters user-defined event ``ev`` from selector ``s``.
+
+  proc unregister*[T](s: Selector[T], fd: int|SocketHandle|cint) =
+    ## Unregisters file/socket descriptor ``fd`` from selector ``s``.
+
+  proc selectInto*[T](s: Selector[T], timeout: int,
+                      results: var openarray[ReadyKey]): int =
+    ## Waits for events registered in selector ``s``.
+    ##
+    ## The ``timeout`` argument specifies the maximum number of milliseconds
+    ## the function will be blocked for if no events are ready. Specifying a
+    ## timeout of ``-1`` causes the function to block indefinitely.
+    ## All available events will be stored in ``results`` array.
+    ##
+    ## Returns number of triggered events.
+
+  proc select*[T](s: Selector[T], timeout: int): seq[ReadyKey] =
+    ## Waits for events registered in selector ``s``.
+    ##
+    ## The ``timeout`` argument specifies the maximum number of milliseconds
+    ## the function will be blocked for if no events are ready. Specifying a
+    ## timeout of ``-1`` causes the function to block indefinitely.
+    ##
+    ## Returns a list of triggered events.
+
+  proc getData*[T](s: Selector[T], fd: SocketHandle|int): var T =
+    ## Retrieves application-defined ``data`` associated with descriptor ``fd``.
+    ## If specified descriptor ``fd`` is not registered, empty/default value
+    ## will be returned.
+
+  proc setData*[T](s: Selector[T], fd: SocketHandle|int, data: var T): bool =
+    ## Associate application-defined ``data`` with descriptor ``fd``.
+    ##
+    ## Returns ``true``, if data was succesfully updated, ``false`` otherwise.
+
+  template isEmpty*[T](s: Selector[T]): bool = # TODO: Why is this a template?
+    ## Returns ``true``, if there are no registered events or descriptors
+    ## in selector.
+
+  template withData*[T](s: Selector[T], fd: SocketHandle|int, value,
+                        body: untyped) =
+    ## Retrieves the application-data assigned with descriptor ``fd``
+    ## to ``value``. This ``value`` can be modified in the scope of
+    ## the ``withData`` call.
+    ##
+    ## .. code-block:: nim
+    ##
+    ##   s.withData(fd, value) do:
+    ##     # block is executed only if ``fd`` registered in selector ``s``
+    ##     value.uid = 1000
+    ##
+
+  template withData*[T](s: Selector[T], fd: SocketHandle|int, value,
+                        body1, body2: untyped) =
+    ## Retrieves the application-data assigned with descriptor ``fd``
+    ## to ``value``. This ``value`` can be modified in the scope of
+    ## the ``withData`` call.
+    ##
+    ## .. code-block:: nim
+    ##
+    ##   s.withData(fd, value) do:
+    ##     # block is executed only if ``fd`` registered in selector ``s``.
+    ##     value.uid = 1000
+    ##   do:
+    ##     # block is executed if ``fd`` not registered in selector ``s``.
+    ##     raise
+    ##
+
+  proc contains*[T](s: Selector[T], fd: SocketHandle|int): bool {.inline.} =
     ## Determines whether selector contains a file descriptor.
 
-  proc `[]`*(s: Selector, fd: SocketHandle): SelectorKey =
+else:
-    ## Retrieves the selector key for ``fd``.
+  when hasThreadSupport:
-
+    import locks
-elif defined(linux):
-  type
-    Selector* = object
-      epollFD: cint
-      events: array[64, epoll_event]
-      when MultiThreaded:
-        fds: SharedTable[SocketHandle, SelectorKey]
-      else:
-        fds: Table[SocketHandle, SelectorKey]
-
-  proc createEventStruct(events: set[Event], fd: SocketHandle): epoll_event =
-    if EvRead in events:
-      result.events = EPOLLIN
-    if EvWrite in events:
-      result.events = result.events or EPOLLOUT
-    result.events = result.events or EPOLLRDHUP
-    result.data.fd = fd.cint
-
-  proc register*(s: var Selector, fd: SocketHandle, events: set[Event],
-                 data: SelectorData) =
-    var event = createEventStruct(events, fd)
-    if events != {}:
-      if epoll_ctl(s.epollFD, EPOLL_CTL_ADD, fd, addr(event)) != 0:
-        raiseOSError(osLastError())
-
-    s.fds[fd] = SelectorKey(fd: fd, events: events, data: data)
-
-  proc update*(s: var Selector, fd: SocketHandle, events: set[Event]) =
-    if s.fds[fd].events != events:
-      if events == {}:
-        # This fd is idle -- it should not be registered to epoll.
-        # But it should remain a part of this selector instance.
-        # This is to prevent epoll_wait from returning immediately
-        # because its got fds which are waiting for no events and
-        # are therefore constantly ready. (leading to 100% CPU usage).
-        if epoll_ctl(s.epollFD, EPOLL_CTL_DEL, fd, nil) != 0:
-          raiseOSError(osLastError())
-        s.fds[fd].events = events
-      else:
-        var event = createEventStruct(events, fd)
-        if s.fds[fd].events == {}:
-          # This fd is idle. It's not a member of this epoll instance and must
-          # be re-registered.
-          if epoll_ctl(s.epollFD, EPOLL_CTL_ADD, fd, addr(event)) != 0:
-            raiseOSError(osLastError())
-        else:
-          if epoll_ctl(s.epollFD, EPOLL_CTL_MOD, fd, addr(event)) != 0:
-            raiseOSError(osLastError())
-        s.fds[fd].events = events
-
-  proc unregister*(s: var Selector, fd: SocketHandle) =
-    if s.fds[fd].events != {}:
-      if epoll_ctl(s.epollFD, EPOLL_CTL_DEL, fd, nil) != 0:
-        let err = osLastError()
-        if err.cint notin {ENOENT, EBADF}:
-          # TODO: Why do we sometimes get an EBADF? Is this normal?
-          raiseOSError(err)
-    s.fds.del(fd)
-
-  proc close*(s: var Selector) =
-    when MultiThreaded: deinitSharedTable(s.fds)
-    if s.epollFD.close() != 0: raiseOSError(osLastError())
-
-  proc epollHasFd(s: Selector, fd: SocketHandle): bool =
-    result = true
-    var event = createEventStruct(s.fds[fd].events, fd)
-    if epoll_ctl(s.epollFD, EPOLL_CTL_MOD, fd, addr(event)) != 0:
-      let err = osLastError()
-      if err.cint in {ENOENT, EBADF}:
-        return false
-      raiseOSError(err)
-
-  proc select*(s: var Selector, timeout: int): seq[ReadyInfo] =
-    result = @[]
-    let evNum = epoll_wait(s.epollFD, addr s.events[0], 64.cint, timeout.cint)
-    if evNum < 0:
-      let err = osLastError()
-      if err.cint == EINTR:
-        return @[]
-      raiseOSError(err)
-    if evNum == 0: return @[]
-    for i in 0 ..< evNum:
-      let fd = s.events[i].data.fd.SocketHandle
-
-      var evSet: set[Event] = {}
-      if (s.events[i].events and EPOLLERR) != 0 or (s.events[i].events and EPOLLHUP) != 0: evSet = evSet + {EvError}
-      if (s.events[i].events and EPOLLIN) != 0: evSet = evSet + {EvRead}
-      if (s.events[i].events and EPOLLOUT) != 0: evSet = evSet + {EvWrite}
-      let selectorKey = s.fds[fd]
-      assert selectorKey.fd != 0.SocketHandle
-      result.add((selectorKey, evSet))
-
-      #echo("Epoll: ", result[i].key.fd, " ", result[i].events, " ", result[i].key.events)
-
-  proc newSelector*(): Selector =
-    result.epollFD = epoll_create(64)
-    if result.epollFD < 0:
-      raiseOSError(osLastError())
-    when MultiThreaded:
-      result.fds = initSharedTable[SocketHandle, SelectorKey]()
-    else:
-      result.fds = initTable[SocketHandle, SelectorKey]()
-
-  proc contains*(s: Selector, fd: SocketHandle): bool =
-    ## Determines whether selector contains a file descriptor.
-    if s.fds.hasKey(fd):
-      # Ensure the underlying epoll instance still contains this fd.
-      if s.fds[fd].events != {}:
-        result = epollHasFd(s, fd)
-      else:
-        result = true
-    else:
-      return false
-
-  proc `[]`*(s: Selector, fd: SocketHandle): SelectorKey =
-    ## Retrieves the selector key for ``fd``.
-    return s.fds[fd]
-
-elif defined(macosx) or defined(freebsd) or defined(openbsd) or defined(netbsd):
-  type
-    Selector* = object
-      kqFD: cint
-      events: array[64, KEvent]
-      when MultiThreaded:
-        fds: SharedTable[SocketHandle, SelectorKey]
-      else:
-        fds: Table[SocketHandle, SelectorKey]
-
-  template modifyKQueue(kqFD: cint, fd: SocketHandle, event: Event,
-                        op: cushort) =
-    var kev = KEvent(ident:  fd.cuint,
-                     filter: if event == EvRead: EVFILT_READ else: EVFILT_WRITE,
-                     flags:  op)
-    if kevent(kqFD, addr kev, 1, nil, 0, nil) == -1:
-      raiseOSError(osLastError())
-
-  proc register*(s: var Selector, fd: SocketHandle, events: set[Event],
-                 data: SelectorData) =
-    for event in events:
-      modifyKQueue(s.kqFD, fd, event, EV_ADD)
-    s.fds[fd] = SelectorKey(fd: fd, events: events, data: data)
-
-  proc update*(s: var Selector, fd: SocketHandle, events: set[Event]) =
-    let previousEvents = s.fds[fd].events
-    if previousEvents != events:
-      for event in events-previousEvents:
-        modifyKQueue(s.kqFD, fd, event, EV_ADD)
-      for event in previousEvents-events:
-        modifyKQueue(s.kqFD, fd, event, EV_DELETE)
-      s.fds[fd].events = events
-
-  proc unregister*(s: var Selector, fd: SocketHandle) =
-    for event in s.fds[fd].events:
-      modifyKQueue(s.kqFD, fd, event, EV_DELETE)
-    s.fds.del(fd)
-
-  proc close*(s: var Selector) =
-    when MultiThreaded: deinitSharedTable(s.fds)
-    if s.kqFD.close() != 0: raiseOSError(osLastError())
-
-  proc select*(s: var Selector, timeout: int): seq[ReadyInfo] =
-    result = @[]
-    var tv =
-      if timeout >= 1000: Timespec(tv_sec: (timeout div 1000).Time, tv_nsec: 0)
-      else: Timespec(tv_sec: 0.Time, tv_nsec: timeout * 1000000)
-    let evNum = kevent(s.kqFD, nil, 0, addr s.events[0], 64.cint, addr tv)
-    if evNum < 0:
-      let err = osLastError()
-      if err.cint == EINTR:
-        return @[]
-      raiseOSError(err)
-    if evNum == 0: return @[]
-    for i in 0 ..< evNum:
-      let fd = s.events[i].ident.SocketHandle
-
-      var evSet: set[Event] = {}
-      if  (s.events[i].flags and EV_EOF) != 0: evSet = evSet + {EvError}
-      if   s.events[i].filter == EVFILT_READ:  evSet = evSet + {EvRead}
-      elif s.events[i].filter == EVFILT_WRITE: evSet = evSet + {EvWrite}
-      let selectorKey = s.fds[fd]
-      assert selectorKey.fd != 0.SocketHandle
-      result.add((selectorKey, evSet))
-
-  proc newSelector*(): Selector =
-    result.kqFD = kqueue()
-    if result.kqFD < 0:
-      raiseOSError(osLastError())
-    when MultiThreaded:
-      result.fds = initSharedTable[SocketHandle, SelectorKey]()
-    else:
-      result.fds = initTable[SocketHandle, SelectorKey]()
-
-  proc contains*(s: Selector, fd: SocketHandle): bool =
-    ## Determines whether selector contains a file descriptor.
-    s.fds.hasKey(fd) # and s.fds[fd].events != {}
-
-  proc `[]`*(s: Selector, fd: SocketHandle): SelectorKey =
-    ## Retrieves the selector key for ``fd``.
-    return s.fds[fd]
-
-elif not defined(nimdoc):
-  # TODO: kqueue for bsd/mac os x.
-  type
-    Selector* = object
-      when MultiThreaded:
-        fds: SharedTable[SocketHandle, SelectorKey]
-      else:
-        fds: Table[SocketHandle, SelectorKey]
-
-  proc register*(s: var Selector, fd: SocketHandle, events: set[Event],
-                 data: SelectorData) =
-    let result = SelectorKey(fd: fd, events: events, data: data)
-    if s.fds.hasKeyOrPut(fd, result):
-      raise newException(ValueError, "File descriptor already exists.")
-
-  proc update*(s: var Selector, fd: SocketHandle, events: set[Event]) =
-    #if not s.fds.hasKey(fd):
-    #  raise newException(ValueError, "File descriptor not found.")
-    s.fds[fd].events = events
-
-  proc unregister*(s: var Selector, fd: SocketHandle) =
-    s.fds.del(fd)
-
-  proc close*(s: var Selector) =
-    when MultiThreaded: deinitSharedTable(s.fds)
-
-  proc timeValFromMilliseconds(timeout: int): TimeVal =
-    if timeout != -1:
-      var seconds = timeout div 1000
-      result.tv_sec = seconds.int32
-      result.tv_usec = ((timeout - seconds * 1000) * 1000).int32
-
-  proc createFdSet(rd, wr: var TFdSet, s: Selector, m: var int) =
-    FD_ZERO(rd); FD_ZERO(wr)
-    for k, v in pairs(s.fds):
-      if EvRead in v.events:
-        m = max(m, int(k))
-        FD_SET(k, rd)
-      if EvWrite in v.events:
-        m = max(m, int(k))
-        FD_SET(k, wr)
-
-  proc getReadyFDs(rd, wr: var TFdSet,
-                   s: var Selector): seq[ReadyInfo] =
-    result = @[]
-    for k, v in pairs(s.fds):
-      var events: set[Event] = {}
-      if FD_ISSET(k, rd) != 0'i32:
-        events = events + {EvRead}
-      if FD_ISSET(k, wr) != 0'i32:
-        events = events + {EvWrite}
-      result.add((v, events))
-
-  proc select*(s: var Selector, timeout: int): seq[ReadyInfo] =
-    var tv {.noInit.}: TimeVal = timeValFromMilliseconds(timeout)
-
-    var rd, wr: TFdSet
-    var m = 0
-    createFdSet(rd, wr, s, m)
-
-    var retCode = 0
-    if timeout != -1:
-      retCode = int(select(cint(m+1), addr(rd), addr(wr), nil, addr(tv)))
-    else:
-      retCode = int(select(cint(m+1), addr(rd), addr(wr), nil, nil))
-
-    if retCode < 0:
-      raiseOSError(osLastError())
-    elif retCode == 0:
-      return @[]
-    else:
-      return getReadyFDs(rd, wr, s)
-
-  proc newSelector*(): Selector =
-    when MultiThreaded:
-      result.fds = initSharedTable[SocketHandle, SelectorKey]()
-    else:
-      result.fds = initTable[SocketHandle, SelectorKey]()
-
-  proc contains*(s: Selector, fd: SocketHandle): bool =
-    return s.fds.hasKey(fd)
-
-  proc `[]`*(s: Selector, fd: SocketHandle): SelectorKey =
-    return s.fds[fd]
-
-proc contains*(s: Selector, key: SelectorKey): bool =
-  ## Determines whether selector contains this selector key. More accurate
-  ## than checking if the file descriptor is in the selector because it
-  ## ensures that the keys are equal. File descriptors may not always be
-  ## unique especially when an fd is closed and then a new one is opened,
-  ## the new one may have the same value.
-  when not defined(nimdoc):
-    return key.fd in s and s.fds[key.fd] == key
-
-proc len*(s: Selector): int =
-  ## Retrieves the number of registered file descriptors in this Selector.
-  when not defined(nimdoc):
-    return s.fds.len
-
-{.deprecated: [TEvent: Event, PSelectorKey: SelectorKey,
-   TReadyInfo: ReadyInfo, PSelector: Selector].}
 
 
-when not defined(testing) and isMainModule and not defined(nimdoc):
-  # Select()
-  import sockets
-
-  when MultiThreaded:
     type
-      SockWrapper = object
+      SharedArray[T] = UncheckedArray[T]
-        sock: Socket
-  else:
-    type
-      SockWrapper = ref object of RootObj
-        sock: Socket
 
-  var sock = socket()
+    proc allocSharedArray[T](nsize: int): ptr SharedArray[T] =
-  if sock == sockets.invalidSocket: raiseOSError(osLastError())
+      result = cast[ptr SharedArray[T]](allocShared0(sizeof(T) * nsize))
-  #sock.setBlocking(false)
-  sock.connect("irc.freenode.net", Port(6667))
 
-  var selector = newSelector()
+    proc deallocSharedArray[T](sa: ptr SharedArray[T]) =
-  var data = SockWrapper(sock: sock)
+      deallocShared(cast[pointer](sa))
-  when MultiThreaded:
+
-    selector.register(sock.getFD, {EvWrite}, addr data)
+  type
+    Event* {.pure.} = enum
+      Read, Write, Timer, Signal, Process, Vnode, User, Error, Oneshot,
+      Finished, VnodeWrite, VnodeDelete, VnodeExtend, VnodeAttrib, VnodeLink,
+      VnodeRename, VnodeRevoke
+
+  type
+    IOSelectorsException* = object of Exception
+
+    ReadyKey* = object
+      fd* : int
+      events*: set[Event]
+
+    SelectorKey[T] = object
+      ident: int
+      events: set[Event]
+      param: int
+      data: T
+
+  proc raiseIOSelectorsError[T](message: T) =
+    var msg = ""
+    when T is string:
+      msg.add(message)
+    elif T is OSErrorCode:
+      msg.add(osErrorMsg(message) & " (code: " & $int(message) & ")")
+    else:
+      msg.add("Internal Error\n")
+    var err = newException(IOSelectorsException, msg)
+    raise err
+
+  proc setNonBlocking(fd: cint) {.inline.} =
+    setBlocking(fd.SocketHandle, false)
+
+  when not defined(windows):
+    import posix
+
+    template setKey(s, pident, pevents, pparam, pdata: untyped) =
+      var skey = addr(s.fds[pident])
+      skey.ident = pident
+      skey.events = pevents
+      skey.param = pparam
+      skey.data = data
+
+  when ioselSupportedPlatform:
+    template blockSignals(newmask: var Sigset, oldmask: var Sigset) =
+      when hasThreadSupport:
+        if posix.pthread_sigmask(SIG_BLOCK, newmask, oldmask) == -1:
+          raiseIOSelectorsError(osLastError())
+      else:
+        if posix.sigprocmask(SIG_BLOCK, newmask, oldmask) == -1:
+          raiseIOSelectorsError(osLastError())
+
+    template unblockSignals(newmask: var Sigset, oldmask: var Sigset) =
+      when hasThreadSupport:
+        if posix.pthread_sigmask(SIG_UNBLOCK, newmask, oldmask) == -1:
+          raiseIOSelectorsError(osLastError())
+      else:
+        if posix.sigprocmask(SIG_UNBLOCK, newmask, oldmask) == -1:
+          raiseIOSelectorsError(osLastError())
+
+  when defined(linux):
+    include ioselects/ioselectors_epoll
+  elif bsdPlatform:
+    include ioselects/ioselectors_kqueue
+  elif defined(windows):
+    include ioselects/ioselectors_select
+  elif defined(solaris):
+    include ioselects/ioselectors_poll # need to replace it with event ports
   else:
-    selector.register(sock.getFD, {EvWrite}, data)
+    include ioselects/ioselectors_poll
-  var i = 0
+
-  while true:
+{.deprecated: [setEvent: trigger].}
-    let ready = selector.select(1000)
+{.deprecated: [register: registerHandle].}
-    echo ready.len
+{.deprecated: [update: updateHandle].}
-    if ready.len > 0: echo ready[0].events
-    i.inc
-    if i == 6:
-      selector.unregister(sock.getFD)
-      selector.close()
-      break

tests/async/tioselectors.nim

@@ -2,7 +2,7 @@ discard """
   file: "tioselectors.nim"
   output: "All tests passed!"
 """
-import ioselectors
+import selectors
 
 const hasThreadSupport = compileOption("threads")
 

tests/testament/categories.nim

@@ -205,7 +205,6 @@ proc ioTests(r: var TResults, cat: Category, options: string) =
 proc asyncTests(r: var TResults, cat: Category, options: string) =
   template test(filename: untyped) =
     testSpec r, makeTest(filename, options, cat)
-    testSpec r, makeTest(filename, options & " -d:upcoming", cat)
   for t in os.walkFiles("tests/async/t*.nim"):
     test(t)