1/*
2 * Copyright (c) 2009-2012 Niels Provos, Nick Mathewson
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 * 3. The name of the author may not be used to endorse or promote products
13 *    derived from this software without specific prior written permission.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#ifndef _WIN32_WINNT
28/* Minimum required for InitializeCriticalSectionAndSpinCount */
29#define _WIN32_WINNT 0x0403
30#endif
31#include <winsock2.h>
32#include <windows.h>
33#include <process.h>
34#include <stdio.h>
35#include <mswsock.h>
36
37#include "event2/util.h"
38#include "util-internal.h"
39#include "iocp-internal.h"
40#include "log-internal.h"
41#include "mm-internal.h"
42#include "event-internal.h"
43#include "evthread-internal.h"
44
45#define NOTIFICATION_KEY ((ULONG_PTR)-1)
46
47void
48event_overlapped_init(struct event_overlapped *o, iocp_callback cb)
49{
50	memset(o, 0, sizeof(struct event_overlapped));
51	o->cb = cb;
52}
53
54static void
55handle_entry(OVERLAPPED *o, ULONG_PTR completion_key, DWORD nBytes, int ok)
56{
57	struct event_overlapped *eo =
58	    EVUTIL_UPCAST(o, struct event_overlapped, overlapped);
59	eo->cb(eo, completion_key, nBytes, ok);
60}
61
62static void
63loop(void *_port)
64{
65	struct event_iocp_port *port = _port;
66	long ms = port->ms;
67	HANDLE p = port->port;
68
69	if (ms <= 0)
70		ms = INFINITE;
71
72	while (1) {
73		OVERLAPPED *overlapped=NULL;
74		ULONG_PTR key=0;
75		DWORD bytes=0;
76		int ok = GetQueuedCompletionStatus(p, &bytes, &key,
77			&overlapped, ms);
78		EnterCriticalSection(&port->lock);
79		if (port->shutdown) {
80			if (--port->n_live_threads == 0)
81				ReleaseSemaphore(port->shutdownSemaphore, 1,
82						NULL);
83			LeaveCriticalSection(&port->lock);
84			return;
85		}
86		LeaveCriticalSection(&port->lock);
87
88		if (key != NOTIFICATION_KEY && overlapped)
89			handle_entry(overlapped, key, bytes, ok);
90		else if (!overlapped)
91			break;
92	}
93	event_warnx("GetQueuedCompletionStatus exited with no event.");
94	EnterCriticalSection(&port->lock);
95	if (--port->n_live_threads == 0)
96		ReleaseSemaphore(port->shutdownSemaphore, 1, NULL);
97	LeaveCriticalSection(&port->lock);
98}
99
100int
101event_iocp_port_associate(struct event_iocp_port *port, evutil_socket_t fd,
102    ev_uintptr_t key)
103{
104	HANDLE h;
105	h = CreateIoCompletionPort((HANDLE)fd, port->port, key, port->n_threads);
106	if (!h)
107		return -1;
108	return 0;
109}
110
111static void *
112get_extension_function(SOCKET s, const GUID *which_fn)
113{
114	void *ptr = NULL;
115	DWORD bytes=0;
116	WSAIoctl(s, SIO_GET_EXTENSION_FUNCTION_POINTER,
117	    (GUID*)which_fn, sizeof(*which_fn),
118	    &ptr, sizeof(ptr),
119	    &bytes, NULL, NULL);
120
121	/* No need to detect errors here: if ptr is set, then we have a good
122	   function pointer.  Otherwise, we should behave as if we had no
123	   function pointer.
124	*/
125	return ptr;
126}
127
128/* Mingw doesn't have these in its mswsock.h.  The values are copied from
129   wine.h.   Perhaps if we copy them exactly, the cargo will come again.
130*/
131#ifndef WSAID_ACCEPTEX
132#define WSAID_ACCEPTEX \
133	{0xb5367df1,0xcbac,0x11cf,{0x95,0xca,0x00,0x80,0x5f,0x48,0xa1,0x92}}
134#endif
135#ifndef WSAID_CONNECTEX
136#define WSAID_CONNECTEX \
137	{0x25a207b9,0xddf3,0x4660,{0x8e,0xe9,0x76,0xe5,0x8c,0x74,0x06,0x3e}}
138#endif
139#ifndef WSAID_GETACCEPTEXSOCKADDRS
140#define WSAID_GETACCEPTEXSOCKADDRS \
141	{0xb5367df2,0xcbac,0x11cf,{0x95,0xca,0x00,0x80,0x5f,0x48,0xa1,0x92}}
142#endif
143
144static void
145init_extension_functions(struct win32_extension_fns *ext)
146{
147	const GUID acceptex = WSAID_ACCEPTEX;
148	const GUID connectex = WSAID_CONNECTEX;
149	const GUID getacceptexsockaddrs = WSAID_GETACCEPTEXSOCKADDRS;
150	SOCKET s = socket(AF_INET, SOCK_STREAM, 0);
151	if (s == INVALID_SOCKET)
152		return;
153	ext->AcceptEx = get_extension_function(s, &acceptex);
154	ext->ConnectEx = get_extension_function(s, &connectex);
155	ext->GetAcceptExSockaddrs = get_extension_function(s,
156	    &getacceptexsockaddrs);
157	closesocket(s);
158}
159
160static struct win32_extension_fns the_extension_fns;
161static int extension_fns_initialized = 0;
162
163const struct win32_extension_fns *
164event_get_win32_extension_fns(void)
165{
166	return &the_extension_fns;
167}
168
169#define N_CPUS_DEFAULT 2
170
171struct event_iocp_port *
172event_iocp_port_launch(int n_cpus)
173{
174	struct event_iocp_port *port;
175	int i;
176
177	if (!extension_fns_initialized)
178		init_extension_functions(&the_extension_fns);
179
180	if (!(port = mm_calloc(1, sizeof(struct event_iocp_port))))
181		return NULL;
182
183	if (n_cpus <= 0)
184		n_cpus = N_CPUS_DEFAULT;
185	port->n_threads = n_cpus * 2;
186	port->threads = mm_calloc(port->n_threads, sizeof(HANDLE));
187	if (!port->threads)
188		goto err;
189
190	port->port = CreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL, 0,
191			n_cpus);
192	port->ms = -1;
193	if (!port->port)
194		goto err;
195
196	port->shutdownSemaphore = CreateSemaphore(NULL, 0, 1, NULL);
197	if (!port->shutdownSemaphore)
198		goto err;
199
200	for (i=0; i<port->n_threads; ++i) {
201		ev_uintptr_t th = _beginthread(loop, 0, port);
202		if (th == (ev_uintptr_t)-1)
203			goto err;
204		port->threads[i] = (HANDLE)th;
205		++port->n_live_threads;
206	}
207
208	InitializeCriticalSectionAndSpinCount(&port->lock, 1000);
209
210	return port;
211err:
212	if (port->port)
213		CloseHandle(port->port);
214	if (port->threads)
215		mm_free(port->threads);
216	if (port->shutdownSemaphore)
217		CloseHandle(port->shutdownSemaphore);
218	mm_free(port);
219	return NULL;
220}
221
222static void
223_event_iocp_port_unlock_and_free(struct event_iocp_port *port)
224{
225	DeleteCriticalSection(&port->lock);
226	CloseHandle(port->port);
227	CloseHandle(port->shutdownSemaphore);
228	mm_free(port->threads);
229	mm_free(port);
230}
231
232static int
233event_iocp_notify_all(struct event_iocp_port *port)
234{
235	int i, r, ok=1;
236	for (i=0; i<port->n_threads; ++i) {
237		r = PostQueuedCompletionStatus(port->port, 0, NOTIFICATION_KEY,
238		    NULL);
239		if (!r)
240			ok = 0;
241	}
242	return ok ? 0 : -1;
243}
244
245int
246event_iocp_shutdown(struct event_iocp_port *port, long waitMsec)
247{
248	DWORD ms = INFINITE;
249	int n;
250
251	EnterCriticalSection(&port->lock);
252	port->shutdown = 1;
253	LeaveCriticalSection(&port->lock);
254	event_iocp_notify_all(port);
255
256	if (waitMsec >= 0)
257		ms = waitMsec;
258
259	WaitForSingleObject(port->shutdownSemaphore, ms);
260	EnterCriticalSection(&port->lock);
261	n = port->n_live_threads;
262	LeaveCriticalSection(&port->lock);
263	if (n == 0) {
264		_event_iocp_port_unlock_and_free(port);
265		return 0;
266	} else {
267		return -1;
268	}
269}
270
271int
272event_iocp_activate_overlapped(
273    struct event_iocp_port *port, struct event_overlapped *o,
274    ev_uintptr_t key, ev_uint32_t n)
275{
276	BOOL r;
277
278	r = PostQueuedCompletionStatus(port->port, n, key, &o->overlapped);
279	return (r==0) ? -1 : 0;
280}
281
282struct event_iocp_port *
283event_base_get_iocp(struct event_base *base)
284{
285#ifdef WIN32
286	return base->iocp;
287#else
288	return NULL;
289#endif
290}
291