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kc3-lang/libevent/event_iocp.c

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  • Author : Nick Mathewson
    Date : 2013-11-01 14:21:54
    Hash : a60632a1
    Message : Merge remote-tracking branch 'origin/patches-2.0'

  • event_iocp.c
  • /*
     * Copyright (c) 2009-2012 Niels Provos, 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.
     */
    #include "evconfig-private.h"
    
    #ifndef _WIN32_WINNT
    /* Minimum required for InitializeCriticalSectionAndSpinCount */
    #define _WIN32_WINNT 0x0403
    #endif
    #include <winsock2.h>
    #include <windows.h>
    #include <process.h>
    #include <stdio.h>
    #include <mswsock.h>
    
    #include "event2/util.h"
    #include "util-internal.h"
    #include "iocp-internal.h"
    #include "log-internal.h"
    #include "mm-internal.h"
    #include "event-internal.h"
    #include "evthread-internal.h"
    
    #define NOTIFICATION_KEY ((ULONG_PTR)-1)
    
    void
    event_overlapped_init_(struct event_overlapped *o, iocp_callback cb)
    {
    	memset(o, 0, sizeof(struct event_overlapped));
    	o->cb = cb;
    }
    
    static void
    handle_entry(OVERLAPPED *o, ULONG_PTR completion_key, DWORD nBytes, int ok)
    {
    	struct event_overlapped *eo =
    	    EVUTIL_UPCAST(o, struct event_overlapped, overlapped);
    	eo->cb(eo, completion_key, nBytes, ok);
    }
    
    static void
    loop(void *port_)
    {
    	struct event_iocp_port *port = port_;
    	long ms = port->ms;
    	HANDLE p = port->port;
    
    	if (ms <= 0)
    		ms = INFINITE;
    
    	while (1) {
    		OVERLAPPED *overlapped=NULL;
    		ULONG_PTR key=0;
    		DWORD bytes=0;
    		int ok = GetQueuedCompletionStatus(p, &bytes, &key,
    			&overlapped, ms);
    		EnterCriticalSection(&port->lock);
    		if (port->shutdown) {
    			if (--port->n_live_threads == 0)
    				ReleaseSemaphore(port->shutdownSemaphore, 1,
    						NULL);
    			LeaveCriticalSection(&port->lock);
    			return;
    		}
    		LeaveCriticalSection(&port->lock);
    
    		if (key != NOTIFICATION_KEY && overlapped)
    			handle_entry(overlapped, key, bytes, ok);
    		else if (!overlapped)
    			break;
    	}
    	event_warnx("GetQueuedCompletionStatus exited with no event.");
    	EnterCriticalSection(&port->lock);
    	if (--port->n_live_threads == 0)
    		ReleaseSemaphore(port->shutdownSemaphore, 1, NULL);
    	LeaveCriticalSection(&port->lock);
    }
    
    int
    event_iocp_port_associate_(struct event_iocp_port *port, evutil_socket_t fd,
        ev_uintptr_t key)
    {
    	HANDLE h;
    	h = CreateIoCompletionPort((HANDLE)fd, port->port, key, port->n_threads);
    	if (!h)
    		return -1;
    	return 0;
    }
    
    static void *
    get_extension_function(SOCKET s, const GUID *which_fn)
    {
    	void *ptr = NULL;
    	DWORD bytes=0;
    	WSAIoctl(s, SIO_GET_EXTENSION_FUNCTION_POINTER,
    	    (GUID*)which_fn, sizeof(*which_fn),
    	    &ptr, sizeof(ptr),
    	    &bytes, NULL, NULL);
    
    	/* No need to detect errors here: if ptr is set, then we have a good
    	   function pointer.  Otherwise, we should behave as if we had no
    	   function pointer.
    	*/
    	return ptr;
    }
    
    /* Mingw doesn't have these in its mswsock.h.  The values are copied from
       wine.h.   Perhaps if we copy them exactly, the cargo will come again.
    */
    #ifndef WSAID_ACCEPTEX
    #define WSAID_ACCEPTEX \
    	{0xb5367df1,0xcbac,0x11cf,{0x95,0xca,0x00,0x80,0x5f,0x48,0xa1,0x92}}
    #endif
    #ifndef WSAID_CONNECTEX
    #define WSAID_CONNECTEX \
    	{0x25a207b9,0xddf3,0x4660,{0x8e,0xe9,0x76,0xe5,0x8c,0x74,0x06,0x3e}}
    #endif
    #ifndef WSAID_GETACCEPTEXSOCKADDRS
    #define WSAID_GETACCEPTEXSOCKADDRS \
    	{0xb5367df2,0xcbac,0x11cf,{0x95,0xca,0x00,0x80,0x5f,0x48,0xa1,0x92}}
    #endif
    
    static int extension_fns_initialized = 0;
    
    static void
    init_extension_functions(struct win32_extension_fns *ext)
    {
    	const GUID acceptex = WSAID_ACCEPTEX;
    	const GUID connectex = WSAID_CONNECTEX;
    	const GUID getacceptexsockaddrs = WSAID_GETACCEPTEXSOCKADDRS;
    	SOCKET s = socket(AF_INET, SOCK_STREAM, 0);
    	if (s == INVALID_SOCKET)
    		return;
    	ext->AcceptEx = get_extension_function(s, &acceptex);
    	ext->ConnectEx = get_extension_function(s, &connectex);
    	ext->GetAcceptExSockaddrs = get_extension_function(s,
    	    &getacceptexsockaddrs);
    	closesocket(s);
    
    	extension_fns_initialized = 1;
    }
    
    static struct win32_extension_fns the_extension_fns;
    
    const struct win32_extension_fns *
    event_get_win32_extension_fns_(void)
    {
    	return &the_extension_fns;
    }
    
    #define N_CPUS_DEFAULT 2
    
    struct event_iocp_port *
    event_iocp_port_launch_(int n_cpus)
    {
    	struct event_iocp_port *port;
    	int i;
    
    	if (!extension_fns_initialized)
    		init_extension_functions(&the_extension_fns);
    
    	if (!(port = mm_calloc(1, sizeof(struct event_iocp_port))))
    		return NULL;
    
    	if (n_cpus <= 0)
    		n_cpus = N_CPUS_DEFAULT;
    	port->n_threads = n_cpus * 2;
    	port->threads = mm_calloc(port->n_threads, sizeof(HANDLE));
    	if (!port->threads)
    		goto err;
    
    	port->port = CreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL, 0,
    			n_cpus);
    	port->ms = -1;
    	if (!port->port)
    		goto err;
    
    	port->shutdownSemaphore = CreateSemaphore(NULL, 0, 1, NULL);
    	if (!port->shutdownSemaphore)
    		goto err;
    
    	for (i=0; i<port->n_threads; ++i) {
    		ev_uintptr_t th = _beginthread(loop, 0, port);
    		if (th == (ev_uintptr_t)-1)
    			goto err;
    		port->threads[i] = (HANDLE)th;
    		++port->n_live_threads;
    	}
    
    	InitializeCriticalSectionAndSpinCount(&port->lock, 1000);
    
    	return port;
    err:
    	if (port->port)
    		CloseHandle(port->port);
    	if (port->threads)
    		mm_free(port->threads);
    	if (port->shutdownSemaphore)
    		CloseHandle(port->shutdownSemaphore);
    	mm_free(port);
    	return NULL;
    }
    
    static void
    event_iocp_port_unlock_and_free_(struct event_iocp_port *port)
    {
    	DeleteCriticalSection(&port->lock);
    	CloseHandle(port->port);
    	CloseHandle(port->shutdownSemaphore);
    	mm_free(port->threads);
    	mm_free(port);
    }
    
    static int
    event_iocp_notify_all(struct event_iocp_port *port)
    {
    	int i, r, ok=1;
    	for (i=0; i<port->n_threads; ++i) {
    		r = PostQueuedCompletionStatus(port->port, 0, NOTIFICATION_KEY,
    		    NULL);
    		if (!r)
    			ok = 0;
    	}
    	return ok ? 0 : -1;
    }
    
    int
    event_iocp_shutdown_(struct event_iocp_port *port, long waitMsec)
    {
    	DWORD ms = INFINITE;
    	int n;
    
    	EnterCriticalSection(&port->lock);
    	port->shutdown = 1;
    	LeaveCriticalSection(&port->lock);
    	event_iocp_notify_all(port);
    
    	if (waitMsec >= 0)
    		ms = waitMsec;
    
    	WaitForSingleObject(port->shutdownSemaphore, ms);
    	EnterCriticalSection(&port->lock);
    	n = port->n_live_threads;
    	LeaveCriticalSection(&port->lock);
    	if (n == 0) {
    		event_iocp_port_unlock_and_free_(port);
    		return 0;
    	} else {
    		return -1;
    	}
    }
    
    int
    event_iocp_activate_overlapped_(
        struct event_iocp_port *port, struct event_overlapped *o,
        ev_uintptr_t key, ev_uint32_t n)
    {
    	BOOL r;
    
    	r = PostQueuedCompletionStatus(port->port, n, key, &o->overlapped);
    	return (r==0) ? -1 : 0;
    }
    
    struct event_iocp_port *
    event_base_get_iocp_(struct event_base *base)
    {
    #ifdef _WIN32
    	return base->iocp;
    #else
    	return NULL;
    #endif
    }