xref: /freebsd/contrib/ntp/sntp/libevent/event_iocp.c (revision 0b57cec536236d46e3dba9bd041533462f33dbb7)
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 #include "evconfig-private.h"
27 
28 #ifndef _WIN32_WINNT
29 /* Minimum required for InitializeCriticalSectionAndSpinCount */
30 #define _WIN32_WINNT 0x0403
31 #endif
32 #include <winsock2.h>
33 #include <windows.h>
34 #include <process.h>
35 #include <stdio.h>
36 #include <mswsock.h>
37 
38 #include "event2/util.h"
39 #include "util-internal.h"
40 #include "iocp-internal.h"
41 #include "log-internal.h"
42 #include "mm-internal.h"
43 #include "event-internal.h"
44 #include "evthread-internal.h"
45 
46 #define NOTIFICATION_KEY ((ULONG_PTR)-1)
47 
48 void
49 event_overlapped_init_(struct event_overlapped *o, iocp_callback cb)
50 {
51 	memset(o, 0, sizeof(struct event_overlapped));
52 	o->cb = cb;
53 }
54 
55 static void
56 handle_entry(OVERLAPPED *o, ULONG_PTR completion_key, DWORD nBytes, int ok)
57 {
58 	struct event_overlapped *eo =
59 	    EVUTIL_UPCAST(o, struct event_overlapped, overlapped);
60 	eo->cb(eo, completion_key, nBytes, ok);
61 }
62 
63 static void
64 loop(void *port_)
65 {
66 	struct event_iocp_port *port = port_;
67 	long ms = port->ms;
68 	HANDLE p = port->port;
69 
70 	if (ms <= 0)
71 		ms = INFINITE;
72 
73 	while (1) {
74 		OVERLAPPED *overlapped=NULL;
75 		ULONG_PTR key=0;
76 		DWORD bytes=0;
77 		int ok = GetQueuedCompletionStatus(p, &bytes, &key,
78 			&overlapped, ms);
79 		EnterCriticalSection(&port->lock);
80 		if (port->shutdown) {
81 			if (--port->n_live_threads == 0)
82 				ReleaseSemaphore(port->shutdownSemaphore, 1,
83 						NULL);
84 			LeaveCriticalSection(&port->lock);
85 			return;
86 		}
87 		LeaveCriticalSection(&port->lock);
88 
89 		if (key != NOTIFICATION_KEY && overlapped)
90 			handle_entry(overlapped, key, bytes, ok);
91 		else if (!overlapped)
92 			break;
93 	}
94 	event_warnx("GetQueuedCompletionStatus exited with no event.");
95 	EnterCriticalSection(&port->lock);
96 	if (--port->n_live_threads == 0)
97 		ReleaseSemaphore(port->shutdownSemaphore, 1, NULL);
98 	LeaveCriticalSection(&port->lock);
99 }
100 
101 int
102 event_iocp_port_associate_(struct event_iocp_port *port, evutil_socket_t fd,
103     ev_uintptr_t key)
104 {
105 	HANDLE h;
106 	h = CreateIoCompletionPort((HANDLE)fd, port->port, key, port->n_threads);
107 	if (!h)
108 		return -1;
109 	return 0;
110 }
111 
112 static void *
113 get_extension_function(SOCKET s, const GUID *which_fn)
114 {
115 	void *ptr = NULL;
116 	DWORD bytes=0;
117 	WSAIoctl(s, SIO_GET_EXTENSION_FUNCTION_POINTER,
118 	    (GUID*)which_fn, sizeof(*which_fn),
119 	    &ptr, sizeof(ptr),
120 	    &bytes, NULL, NULL);
121 
122 	/* No need to detect errors here: if ptr is set, then we have a good
123 	   function pointer.  Otherwise, we should behave as if we had no
124 	   function pointer.
125 	*/
126 	return ptr;
127 }
128 
129 /* Mingw doesn't have these in its mswsock.h.  The values are copied from
130    wine.h.   Perhaps if we copy them exactly, the cargo will come again.
131 */
132 #ifndef WSAID_ACCEPTEX
133 #define WSAID_ACCEPTEX \
134 	{0xb5367df1,0xcbac,0x11cf,{0x95,0xca,0x00,0x80,0x5f,0x48,0xa1,0x92}}
135 #endif
136 #ifndef WSAID_CONNECTEX
137 #define WSAID_CONNECTEX \
138 	{0x25a207b9,0xddf3,0x4660,{0x8e,0xe9,0x76,0xe5,0x8c,0x74,0x06,0x3e}}
139 #endif
140 #ifndef WSAID_GETACCEPTEXSOCKADDRS
141 #define WSAID_GETACCEPTEXSOCKADDRS \
142 	{0xb5367df2,0xcbac,0x11cf,{0x95,0xca,0x00,0x80,0x5f,0x48,0xa1,0x92}}
143 #endif
144 
145 static int extension_fns_initialized = 0;
146 
147 static void
148 init_extension_functions(struct win32_extension_fns *ext)
149 {
150 	const GUID acceptex = WSAID_ACCEPTEX;
151 	const GUID connectex = WSAID_CONNECTEX;
152 	const GUID getacceptexsockaddrs = WSAID_GETACCEPTEXSOCKADDRS;
153 	SOCKET s = socket(AF_INET, SOCK_STREAM, 0);
154 	if (s == INVALID_SOCKET)
155 		return;
156 	ext->AcceptEx = get_extension_function(s, &acceptex);
157 	ext->ConnectEx = get_extension_function(s, &connectex);
158 	ext->GetAcceptExSockaddrs = get_extension_function(s,
159 	    &getacceptexsockaddrs);
160 	closesocket(s);
161 
162 	extension_fns_initialized = 1;
163 }
164 
165 static struct win32_extension_fns the_extension_fns;
166 
167 const struct win32_extension_fns *
168 event_get_win32_extension_fns_(void)
169 {
170 	return &the_extension_fns;
171 }
172 
173 #define N_CPUS_DEFAULT 2
174 
175 struct event_iocp_port *
176 event_iocp_port_launch_(int n_cpus)
177 {
178 	struct event_iocp_port *port;
179 	int i;
180 
181 	if (!extension_fns_initialized)
182 		init_extension_functions(&the_extension_fns);
183 
184 	if (!(port = mm_calloc(1, sizeof(struct event_iocp_port))))
185 		return NULL;
186 
187 	if (n_cpus <= 0)
188 		n_cpus = N_CPUS_DEFAULT;
189 	port->n_threads = n_cpus * 2;
190 	port->threads = mm_calloc(port->n_threads, sizeof(HANDLE));
191 	if (!port->threads)
192 		goto err;
193 
194 	port->port = CreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL, 0,
195 			n_cpus);
196 	port->ms = -1;
197 	if (!port->port)
198 		goto err;
199 
200 	port->shutdownSemaphore = CreateSemaphore(NULL, 0, 1, NULL);
201 	if (!port->shutdownSemaphore)
202 		goto err;
203 
204 	for (i=0; i<port->n_threads; ++i) {
205 		ev_uintptr_t th = _beginthread(loop, 0, port);
206 		if (th == (ev_uintptr_t)-1)
207 			goto err;
208 		port->threads[i] = (HANDLE)th;
209 		++port->n_live_threads;
210 	}
211 
212 	InitializeCriticalSectionAndSpinCount(&port->lock, 1000);
213 
214 	return port;
215 err:
216 	if (port->port)
217 		CloseHandle(port->port);
218 	if (port->threads)
219 		mm_free(port->threads);
220 	if (port->shutdownSemaphore)
221 		CloseHandle(port->shutdownSemaphore);
222 	mm_free(port);
223 	return NULL;
224 }
225 
226 static void
227 event_iocp_port_unlock_and_free_(struct event_iocp_port *port)
228 {
229 	DeleteCriticalSection(&port->lock);
230 	CloseHandle(port->port);
231 	CloseHandle(port->shutdownSemaphore);
232 	mm_free(port->threads);
233 	mm_free(port);
234 }
235 
236 static int
237 event_iocp_notify_all(struct event_iocp_port *port)
238 {
239 	int i, r, ok=1;
240 	for (i=0; i<port->n_threads; ++i) {
241 		r = PostQueuedCompletionStatus(port->port, 0, NOTIFICATION_KEY,
242 		    NULL);
243 		if (!r)
244 			ok = 0;
245 	}
246 	return ok ? 0 : -1;
247 }
248 
249 int
250 event_iocp_shutdown_(struct event_iocp_port *port, long waitMsec)
251 {
252 	DWORD ms = INFINITE;
253 	int n;
254 
255 	EnterCriticalSection(&port->lock);
256 	port->shutdown = 1;
257 	LeaveCriticalSection(&port->lock);
258 	event_iocp_notify_all(port);
259 
260 	if (waitMsec >= 0)
261 		ms = waitMsec;
262 
263 	WaitForSingleObject(port->shutdownSemaphore, ms);
264 	EnterCriticalSection(&port->lock);
265 	n = port->n_live_threads;
266 	LeaveCriticalSection(&port->lock);
267 	if (n == 0) {
268 		event_iocp_port_unlock_and_free_(port);
269 		return 0;
270 	} else {
271 		return -1;
272 	}
273 }
274 
275 int
276 event_iocp_activate_overlapped_(
277     struct event_iocp_port *port, struct event_overlapped *o,
278     ev_uintptr_t key, ev_uint32_t n)
279 {
280 	BOOL r;
281 
282 	r = PostQueuedCompletionStatus(port->port, n, key, &o->overlapped);
283 	return (r==0) ? -1 : 0;
284 }
285 
286 struct event_iocp_port *
287 event_base_get_iocp_(struct event_base *base)
288 {
289 #ifdef _WIN32
290 	return base->iocp;
291 #else
292 	return NULL;
293 #endif
294 }
295