diff options
Diffstat (limited to 'lib/pure/ioselectors.nim')
| -rw-r--r-- | lib/pure/ioselectors.nim | 255 |
1 files changed, 255 insertions, 0 deletions
diff --git a/lib/pure/ioselectors.nim b/lib/pure/ioselectors.nim new file mode 100644 index 000000000..a5d5d2c01 --- /dev/null +++ b/lib/pure/ioselectors.nim @@ -0,0 +1,255 @@ +# +# +# 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. +## +## Partially supported OS: Windows (only sockets and user events), +## Solaris (files, sockets, handles and user events). +## +## TODO: ``/dev/poll``, ``event ports`` and filesystem events. + +import os + +const hasThreadSupport = compileOption("threads") and defined(threadsafe) + +const supportedPlatform = defined(macosx) or defined(freebsd) or + defined(netbsd) or defined(openbsd) or + defined(linux) + +const bsdPlatform = defined(macosx) or defined(freebsd) or + defined(netbsd) or defined(openbsd) + + +when defined(nimdoc): + 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, ## Currently not supported + User, ## User event is raised + Error ## Error happens while waiting, for descriptor + + ReadyKey*[T] = object + ## An object which holds result for descriptor + fd* : int ## file/socket descriptor + events*: set[Event] ## set of events + data*: T ## application-defined data + + 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 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 flush*[T](s: Selector[T]) = + ## Flushes all changes was made to kernel pool/queue. + ## This function is usefull only for BSD and MacOS, because + ## kqueue supports bulk changes to be made. + ## On Linux/Windows and other Posix compatible operation systems, + ## ``flush`` is alias for `discard`. + + proc selectInto*[T](s: Selector[T], timeout: int, + results: var openarray[ReadyKey[T]]): 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[T]] = + ## 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. + + 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, 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, 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 {.unchecked.}[T] = array[0..100, 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 + + ReadyKey*[T] = object + fd* : int + events*: set[Event] + data*: T + + SelectorKey[T] = object + ident: int + events: set[Event] + param: int + key: ReadyKey[T] + + when not defined(windows): + import posix + proc setNonBlocking(fd: cint) {.inline.} = + var x = fcntl(fd, F_GETFL, 0) + if x == -1: + raiseOSError(osLastError()) + else: + var mode = x or O_NONBLOCK + if fcntl(fd, F_SETFL, mode) == -1: + raiseOSError(osLastError()) + + template setKey(s, pident, pkeyfd, pevents, pparam, pdata) = + var skey = addr(s.fds[pident]) + skey.ident = pident + skey.events = pevents + skey.param = pparam + skey.key.fd = pkeyfd + skey.key.data = pdata + + when supportedPlatform: + template blockSignals(newmask: var Sigset, oldmask: var Sigset) = + when hasThreadSupport: + if posix.pthread_sigmask(SIG_BLOCK, newmask, oldmask) == -1: + raiseOSError(osLastError()) + else: + if posix.sigprocmask(SIG_BLOCK, newmask, oldmask) == -1: + raiseOSError(osLastError()) + + template unblockSignals(newmask: var Sigset, oldmask: var Sigset) = + when hasThreadSupport: + if posix.pthread_sigmask(SIG_UNBLOCK, newmask, oldmask) == -1: + raiseOSError(osLastError()) + else: + if posix.sigprocmask(SIG_UNBLOCK, newmask, oldmask) == -1: + raiseOSError(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 |