1 /*	$NetBSD: iocp-internal.h,v 1.1.1.1 2013/04/11 16:43:29 christos Exp $	*/
2 /*
3  * Copyright (c) 2009-2012 Niels Provos and Nick Mathewson
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. The name of the author may not be used to endorse or promote products
14  *    derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #ifndef _EVENT_IOCP_INTERNAL_H
29 #define _EVENT_IOCP_INTERNAL_H
30 
31 #ifdef __cplusplus
32 extern "C" {
33 #endif
34 
35 struct event_overlapped;
36 struct event_iocp_port;
37 struct evbuffer;
38 typedef void (*iocp_callback)(struct event_overlapped *, ev_uintptr_t, ev_ssize_t, int success);
39 
40 /* This whole file is actually win32 only. We wrap the structures in a win32
41  * ifdef so that we can test-compile code that uses these interfaces on
42  * non-win32 platforms. */
43 #ifdef WIN32
44 
45 /**
46    Internal use only.  Wraps an OVERLAPPED that we're using for libevent
47    functionality.  Whenever an event_iocp_port gets an event for a given
48    OVERLAPPED*, it upcasts the pointer to an event_overlapped, and calls the
49    iocp_callback function with the event_overlapped, the iocp key, and the
50    number of bytes transferred as arguments.
51  */
52 struct event_overlapped {
53 	OVERLAPPED overlapped;
54 	iocp_callback cb;
55 };
56 
57 /* Mingw's headers don't define LPFN_ACCEPTEX. */
58 
59 typedef BOOL (WINAPI *AcceptExPtr)(SOCKET, SOCKET, PVOID, DWORD, DWORD, DWORD, LPDWORD, LPOVERLAPPED);
60 typedef BOOL (WINAPI *ConnectExPtr)(SOCKET, const struct sockaddr *, int, PVOID, DWORD, LPDWORD, LPOVERLAPPED);
61 typedef void (WINAPI *GetAcceptExSockaddrsPtr)(PVOID, DWORD, DWORD, DWORD, LPSOCKADDR *, LPINT, LPSOCKADDR *, LPINT);
62 
63 /** Internal use only. Holds pointers to functions that only some versions of
64     Windows provide.
65  */
66 struct win32_extension_fns {
67 	AcceptExPtr AcceptEx;
68 	ConnectExPtr ConnectEx;
69 	GetAcceptExSockaddrsPtr GetAcceptExSockaddrs;
70 };
71 
72 /**
73     Internal use only. Stores a Windows IO Completion port, along with
74     related data.
75  */
76 struct event_iocp_port {
77 	/** The port itself */
78 	HANDLE port;
79 	/* A lock to cover internal structures. */
80 	CRITICAL_SECTION lock;
81 	/** Number of threads ever open on the port. */
82 	short n_threads;
83 	/** True iff we're shutting down all the threads on this port */
84 	short shutdown;
85 	/** How often the threads on this port check for shutdown and other
86 	 * conditions */
87 	long ms;
88 	/* The threads that are waiting for events. */
89 	HANDLE *threads;
90 	/** Number of threads currently open on this port. */
91 	short n_live_threads;
92 	/** A semaphore to signal when we are done shutting down. */
93 	HANDLE *shutdownSemaphore;
94 };
95 
96 const struct win32_extension_fns *event_get_win32_extension_fns(void);
97 #else
98 /* Dummy definition so we can test-compile more things on unix. */
99 struct event_overlapped {
100 	iocp_callback cb;
101 };
102 #endif
103 
104 /** Initialize the fields in an event_overlapped.
105 
106     @param overlapped The struct event_overlapped to initialize
107     @param cb The callback that should be invoked once the IO operation has
108 	finished.
109  */
110 void event_overlapped_init(struct event_overlapped *, iocp_callback cb);
111 
112 /** Allocate and return a new evbuffer that supports overlapped IO on a given
113     socket.  The socket must be associated with an IO completion port using
114     event_iocp_port_associate.
115 */
116 struct evbuffer *evbuffer_overlapped_new(evutil_socket_t fd);
117 
118 /** XXXX Document (nickm) */
119 evutil_socket_t _evbuffer_overlapped_get_fd(struct evbuffer *buf);
120 
121 void _evbuffer_overlapped_set_fd(struct evbuffer *buf, evutil_socket_t fd);
122 
123 /** Start reading data onto the end of an overlapped evbuffer.
124 
125     An evbuffer can only have one read pending at a time.  While the read
126     is in progress, no other data may be added to the end of the buffer.
127     The buffer must be created with event_overlapped_init().
128     evbuffer_commit_read() must be called in the completion callback.
129 
130     @param buf The buffer to read onto
131     @param n The number of bytes to try to read.
132     @param ol Overlapped object with associated completion callback.
133     @return 0 on success, -1 on error.
134  */
135 int evbuffer_launch_read(struct evbuffer *buf, size_t n, struct event_overlapped *ol);
136 
137 /** Start writing data from the start of an evbuffer.
138 
139     An evbuffer can only have one write pending at a time.  While the write is
140     in progress, no other data may be removed from the front of the buffer.
141     The buffer must be created with event_overlapped_init().
142     evbuffer_commit_write() must be called in the completion callback.
143 
144     @param buf The buffer to read onto
145     @param n The number of bytes to try to read.
146     @param ol Overlapped object with associated completion callback.
147     @return 0 on success, -1 on error.
148  */
149 int evbuffer_launch_write(struct evbuffer *buf, ev_ssize_t n, struct event_overlapped *ol);
150 
151 /** XXX document */
152 void evbuffer_commit_read(struct evbuffer *, ev_ssize_t);
153 void evbuffer_commit_write(struct evbuffer *, ev_ssize_t);
154 
155 /** Create an IOCP, and launch its worker threads.  Internal use only.
156 
157     This interface is unstable, and will change.
158  */
159 struct event_iocp_port *event_iocp_port_launch(int n_cpus);
160 
161 /** Associate a file descriptor with an iocp, such that overlapped IO on the
162     fd will happen on one of the iocp's worker threads.
163 */
164 int event_iocp_port_associate(struct event_iocp_port *port, evutil_socket_t fd,
165     ev_uintptr_t key);
166 
167 /** Tell all threads serving an iocp to stop.  Wait for up to waitMsec for all
168     the threads to finish whatever they're doing.  If waitMsec is -1, wait
169     as long as required.  If all the threads are done, free the port and return
170     0. Otherwise, return -1.  If you get a -1 return value, it is safe to call
171     this function again.
172 */
173 int event_iocp_shutdown(struct event_iocp_port *port, long waitMsec);
174 
175 /* FIXME document. */
176 int event_iocp_activate_overlapped(struct event_iocp_port *port,
177     struct event_overlapped *o,
178     ev_uintptr_t key, ev_uint32_t n_bytes);
179 
180 struct event_base;
181 /* FIXME document. */
182 struct event_iocp_port *event_base_get_iocp(struct event_base *base);
183 
184 /* FIXME document. */
185 int event_base_start_iocp(struct event_base *base, int n_cpus);
186 void event_base_stop_iocp(struct event_base *base);
187 
188 /* FIXME document. */
189 struct bufferevent *bufferevent_async_new(struct event_base *base,
190     evutil_socket_t fd, int options);
191 
192 /* FIXME document. */
193 void bufferevent_async_set_connected(struct bufferevent *bev);
194 int bufferevent_async_can_connect(struct bufferevent *bev);
195 int bufferevent_async_connect(struct bufferevent *bev, evutil_socket_t fd,
196 	const struct sockaddr *sa, int socklen);
197 
198 #ifdef __cplusplus
199 }
200 #endif
201 
202 #endif
203