1 /*
2 * Copyright (c) 2009-2012 Niels Provos and 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 _EVENT_IOCP_INTERNAL_H
28 #define _EVENT_IOCP_INTERNAL_H
29
30 #ifdef __cplusplus
31 extern "C" {
32 #endif
33
34 struct event_overlapped;
35 struct event_iocp_port;
36 struct evbuffer;
37 typedef void (*iocp_callback)(struct event_overlapped *, ev_uintptr_t, ev_ssize_t, int success);
38
39 /* This whole file is actually win32 only. We wrap the structures in a win32
40 * ifdef so that we can test-compile code that uses these interfaces on
41 * non-win32 platforms. */
42 #ifdef WIN32
43
44 /**
45 Internal use only. Wraps an OVERLAPPED that we're using for libevent
46 functionality. Whenever an event_iocp_port gets an event for a given
47 OVERLAPPED*, it upcasts the pointer to an event_overlapped, and calls the
48 iocp_callback function with the event_overlapped, the iocp key, and the
49 number of bytes transferred as arguments.
50 */
51 struct event_overlapped {
52 OVERLAPPED overlapped;
53 iocp_callback cb;
54 };
55
56 /* Mingw's headers don't define LPFN_ACCEPTEX. */
57
58 typedef BOOL (WINAPI *AcceptExPtr)(SOCKET, SOCKET, PVOID, DWORD, DWORD, DWORD, LPDWORD, LPOVERLAPPED);
59 typedef BOOL (WINAPI *ConnectExPtr)(SOCKET, const struct sockaddr *, int, PVOID, DWORD, LPDWORD, LPOVERLAPPED);
60 typedef void (WINAPI *GetAcceptExSockaddrsPtr)(PVOID, DWORD, DWORD, DWORD, LPSOCKADDR *, LPINT, LPSOCKADDR *, LPINT);
61
62 /** Internal use only. Holds pointers to functions that only some versions of
63 Windows provide.
64 */
65 struct win32_extension_fns {
66 AcceptExPtr AcceptEx;
67 ConnectExPtr ConnectEx;
68 GetAcceptExSockaddrsPtr GetAcceptExSockaddrs;
69 };
70
71 /**
72 Internal use only. Stores a Windows IO Completion port, along with
73 related data.
74 */
75 struct event_iocp_port {
76 /** The port itself */
77 HANDLE port;
78 /* A lock to cover internal structures. */
79 CRITICAL_SECTION lock;
80 /** Number of threads ever open on the port. */
81 short n_threads;
82 /** True iff we're shutting down all the threads on this port */
83 short shutdown;
84 /** How often the threads on this port check for shutdown and other
85 * conditions */
86 long ms;
87 /* The threads that are waiting for events. */
88 HANDLE *threads;
89 /** Number of threads currently open on this port. */
90 short n_live_threads;
91 /** A semaphore to signal when we are done shutting down. */
92 HANDLE *shutdownSemaphore;
93 };
94
95 const struct win32_extension_fns *event_get_win32_extension_fns(void);
96 #else
97 /* Dummy definition so we can test-compile more things on unix. */
98 struct event_overlapped {
99 iocp_callback cb;
100 };
101 #endif
102
103 /** Initialize the fields in an event_overlapped.
104
105 @param overlapped The struct event_overlapped to initialize
106 @param cb The callback that should be invoked once the IO operation has
107 finished.
108 */
109 void event_overlapped_init(struct event_overlapped *, iocp_callback cb);
110
111 /** Allocate and return a new evbuffer that supports overlapped IO on a given
112 socket. The socket must be associated with an IO completion port using
113 event_iocp_port_associate.
114 */
115 struct evbuffer *evbuffer_overlapped_new(evutil_socket_t fd);
116
117 /** XXXX Document (nickm) */
118 evutil_socket_t _evbuffer_overlapped_get_fd(struct evbuffer *buf);
119
120 void _evbuffer_overlapped_set_fd(struct evbuffer *buf, evutil_socket_t fd);
121
122 /** Start reading data onto the end of an overlapped evbuffer.
123
124 An evbuffer can only have one read pending at a time. While the read
125 is in progress, no other data may be added to the end of the buffer.
126 The buffer must be created with event_overlapped_init().
127 evbuffer_commit_read() must be called in the completion callback.
128
129 @param buf The buffer to read onto
130 @param n The number of bytes to try to read.
131 @param ol Overlapped object with associated completion callback.
132 @return 0 on success, -1 on error.
133 */
134 int evbuffer_launch_read(struct evbuffer *buf, size_t n, struct event_overlapped *ol);
135
136 /** Start writing data from the start of an evbuffer.
137
138 An evbuffer can only have one write pending at a time. While the write is
139 in progress, no other data may be removed from the front of the buffer.
140 The buffer must be created with event_overlapped_init().
141 evbuffer_commit_write() must be called in the completion callback.
142
143 @param buf The buffer to read onto
144 @param n The number of bytes to try to read.
145 @param ol Overlapped object with associated completion callback.
146 @return 0 on success, -1 on error.
147 */
148 int evbuffer_launch_write(struct evbuffer *buf, ev_ssize_t n, struct event_overlapped *ol);
149
150 /** XXX document */
151 void evbuffer_commit_read(struct evbuffer *, ev_ssize_t);
152 void evbuffer_commit_write(struct evbuffer *, ev_ssize_t);
153
154 /** Create an IOCP, and launch its worker threads. Internal use only.
155
156 This interface is unstable, and will change.
157 */
158 struct event_iocp_port *event_iocp_port_launch(int n_cpus);
159
160 /** Associate a file descriptor with an iocp, such that overlapped IO on the
161 fd will happen on one of the iocp's worker threads.
162 */
163 int event_iocp_port_associate(struct event_iocp_port *port, evutil_socket_t fd,
164 ev_uintptr_t key);
165
166 /** Tell all threads serving an iocp to stop. Wait for up to waitMsec for all
167 the threads to finish whatever they're doing. If waitMsec is -1, wait
168 as long as required. If all the threads are done, free the port and return
169 0. Otherwise, return -1. If you get a -1 return value, it is safe to call
170 this function again.
171 */
172 int event_iocp_shutdown(struct event_iocp_port *port, long waitMsec);
173
174 /* FIXME document. */
175 int event_iocp_activate_overlapped(struct event_iocp_port *port,
176 struct event_overlapped *o,
177 ev_uintptr_t key, ev_uint32_t n_bytes);
178
179 struct event_base;
180 /* FIXME document. */
181 struct event_iocp_port *event_base_get_iocp(struct event_base *base);
182
183 /* FIXME document. */
184 int event_base_start_iocp(struct event_base *base, int n_cpus);
185 void event_base_stop_iocp(struct event_base *base);
186
187 /* FIXME document. */
188 struct bufferevent *bufferevent_async_new(struct event_base *base,
189 evutil_socket_t fd, int options);
190
191 /* FIXME document. */
192 void bufferevent_async_set_connected(struct bufferevent *bev);
193 int bufferevent_async_can_connect(struct bufferevent *bev);
194 int bufferevent_async_connect(struct bufferevent *bev, evutil_socket_t fd,
195 const struct sockaddr *sa, int socklen);
196
197 #ifdef __cplusplus
198 }
199 #endif
200
201 #endif