/*
* Copyright (c) 2009-2012 Niels Provos and Nick Mathewson
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/* This whole file is actually win32 only. We wrap the structures in a win32
* ifdef so that we can test-compile code that uses these interfaces on
* non-win32 platforms. */
#ifdef _WIN32
/**
Internal use only. Wraps an OVERLAPPED that we're using for libevent
functionality. Whenever an event_iocp_port gets an event for a given
OVERLAPPED*, it upcasts the pointer to an event_overlapped, and calls the
iocp_callback function with the event_overlapped, the iocp key, and the
number of bytes transferred as arguments.
*/
struct event_overlapped {
OVERLAPPED overlapped;
iocp_callback cb;
};
/** Internal use only. Holds pointers to functions that only some versions of
Windows provide.
*/
struct win32_extension_fns {
AcceptExPtr AcceptEx;
ConnectExPtr ConnectEx;
GetAcceptExSockaddrsPtr GetAcceptExSockaddrs;
};
/**
Internal use only. Stores a Windows IO Completion port, along with
related data.
*/
struct event_iocp_port {
/** The port itself */
HANDLE port;
/* A lock to cover internal structures. */
CRITICAL_SECTION lock;
/** Number of threads ever open on the port. */
short n_threads;
/** True iff we're shutting down all the threads on this port */
short shutdown;
/** How often the threads on this port check for shutdown and other
* conditions */
long ms;
/* The threads that are waiting for events. */
HANDLE *threads;
/** Number of threads currently open on this port. */
short n_live_threads;
/** A semaphore to signal when we are done shutting down. */
HANDLE *shutdownSemaphore;
};
EVENT2_EXPORT_SYMBOL
const struct win32_extension_fns *event_get_win32_extension_fns_(void);
#else
/* Dummy definition so we can test-compile more things on unix. */
struct event_overlapped {
iocp_callback cb;
};
#endif
/** Initialize the fields in an event_overlapped.
@param overlapped The struct event_overlapped to initialize
@param cb The callback that should be invoked once the IO operation has
finished.
*/
EVENT2_EXPORT_SYMBOL
void event_overlapped_init_(struct event_overlapped *, iocp_callback cb);
/** Allocate and return a new evbuffer that supports overlapped IO on a given
socket. The socket must be associated with an IO completion port using
event_iocp_port_associate_.
*/
EVENT2_EXPORT_SYMBOL
struct evbuffer *evbuffer_overlapped_new_(evutil_socket_t fd);
/** Start reading data onto the end of an overlapped evbuffer.
An evbuffer can only have one read pending at a time. While the read
is in progress, no other data may be added to the end of the buffer.
The buffer must be created with event_overlapped_init_().
evbuffer_commit_read_() must be called in the completion callback.
@param buf The buffer to read onto
@param n The number of bytes to try to read.
@param ol Overlapped object with associated completion callback.
@return 0 on success, -1 on error.
*/
EVENT2_EXPORT_SYMBOL
int evbuffer_launch_read_(struct evbuffer *buf, size_t n, struct event_overlapped *ol);
/** Start writing data from the start of an evbuffer.
An evbuffer can only have one write pending at a time. While the write is
in progress, no other data may be removed from the front of the buffer.
The buffer must be created with event_overlapped_init_().
evbuffer_commit_write_() must be called in the completion callback.
@param buf The buffer to read onto
@param n The number of bytes to try to read.
@param ol Overlapped object with associated completion callback.
@return 0 on success, -1 on error.
*/
EVENT2_EXPORT_SYMBOL
int evbuffer_launch_write_(struct evbuffer *buf, ev_ssize_t n, struct event_overlapped *ol);
/** Create an IOCP, and launch its worker threads. Internal use only.
This interface is unstable, and will change.
*/
EVENT2_EXPORT_SYMBOL
struct event_iocp_port *event_iocp_port_launch_(int n_cpus);
/** Associate a file descriptor with an iocp, such that overlapped IO on the
fd will happen on one of the iocp's worker threads.
*/
EVENT2_EXPORT_SYMBOL
int event_iocp_port_associate_(struct event_iocp_port *port, evutil_socket_t fd,
ev_uintptr_t key);
/** Tell all threads serving an iocp to stop. Wait for up to waitMsec for all
the threads to finish whatever they're doing. If waitMsec is -1, wait
as long as required. If all the threads are done, free the port and return
0. Otherwise, return -1. If you get a -1 return value, it is safe to call
this function again.
*/
EVENT2_EXPORT_SYMBOL
int event_iocp_shutdown_(struct event_iocp_port *port, long waitMsec);
