1/*	$NetBSD: iocp-internal.h,v 1.1.1.3 2021/04/07 02:43:12 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 IOCP_INTERNAL_H_INCLUDED_
29#define IOCP_INTERNAL_H_INCLUDED_
30
31#ifdef __cplusplus
32extern "C" {
33#endif
34
35struct event_overlapped;
36struct event_iocp_port;
37struct evbuffer;
38typedef 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 */
52struct event_overlapped {
53	OVERLAPPED overlapped;
54	iocp_callback cb;
55};
56
57/* Mingw's headers don't define LPFN_ACCEPTEX. */
58
59typedef BOOL (WINAPI *AcceptExPtr)(SOCKET, SOCKET, PVOID, DWORD, DWORD, DWORD, LPDWORD, LPOVERLAPPED);
60typedef BOOL (WINAPI *ConnectExPtr)(SOCKET, const struct sockaddr *, int, PVOID, DWORD, LPDWORD, LPOVERLAPPED);
61typedef 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 */
66struct 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 */
76struct 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
96EVENT2_EXPORT_SYMBOL
97const struct win32_extension_fns *event_get_win32_extension_fns_(void);
98#else
99/* Dummy definition so we can test-compile more things on unix. */
100struct event_overlapped {
101	iocp_callback cb;
102};
103#endif
104
105/** Initialize the fields in an event_overlapped.
106
107    @param overlapped The struct event_overlapped to initialize
108    @param cb The callback that should be invoked once the IO operation has
109	finished.
110 */
111EVENT2_EXPORT_SYMBOL
112void event_overlapped_init_(struct event_overlapped *, iocp_callback cb);
113
114/** Allocate and return a new evbuffer that supports overlapped IO on a given
115    socket.  The socket must be associated with an IO completion port using
116    event_iocp_port_associate_.
117*/
118EVENT2_EXPORT_SYMBOL
119struct evbuffer *evbuffer_overlapped_new_(evutil_socket_t fd);
120
121/** XXXX Document (nickm) */
122evutil_socket_t evbuffer_overlapped_get_fd_(struct evbuffer *buf);
123
124void evbuffer_overlapped_set_fd_(struct evbuffer *buf, evutil_socket_t fd);
125
126/** Start reading data onto the end of an overlapped evbuffer.
127
128    An evbuffer can only have one read pending at a time.  While the read
129    is in progress, no other data may be added to the end of the buffer.
130    The buffer must be created with event_overlapped_init_().
131    evbuffer_commit_read_() must be called in the completion callback.
132
133    @param buf The buffer to read onto
134    @param n The number of bytes to try to read.
135    @param ol Overlapped object with associated completion callback.
136    @return 0 on success, -1 on error.
137 */
138EVENT2_EXPORT_SYMBOL
139int evbuffer_launch_read_(struct evbuffer *buf, size_t n, struct event_overlapped *ol);
140
141/** Start writing data from the start of an evbuffer.
142
143    An evbuffer can only have one write pending at a time.  While the write is
144    in progress, no other data may be removed from the front of the buffer.
145    The buffer must be created with event_overlapped_init_().
146    evbuffer_commit_write_() must be called in the completion callback.
147
148    @param buf The buffer to read onto
149    @param n The number of bytes to try to read.
150    @param ol Overlapped object with associated completion callback.
151    @return 0 on success, -1 on error.
152 */
153EVENT2_EXPORT_SYMBOL
154int evbuffer_launch_write_(struct evbuffer *buf, ev_ssize_t n, struct event_overlapped *ol);
155
156/** XXX document */
157EVENT2_EXPORT_SYMBOL
158void evbuffer_commit_read_(struct evbuffer *, ev_ssize_t);
159EVENT2_EXPORT_SYMBOL
160void evbuffer_commit_write_(struct evbuffer *, ev_ssize_t);
161
162/** Create an IOCP, and launch its worker threads.  Internal use only.
163
164    This interface is unstable, and will change.
165 */
166EVENT2_EXPORT_SYMBOL
167struct event_iocp_port *event_iocp_port_launch_(int n_cpus);
168
169/** Associate a file descriptor with an iocp, such that overlapped IO on the
170    fd will happen on one of the iocp's worker threads.
171*/
172EVENT2_EXPORT_SYMBOL
173int event_iocp_port_associate_(struct event_iocp_port *port, evutil_socket_t fd,
174    ev_uintptr_t key);
175
176/** Tell all threads serving an iocp to stop.  Wait for up to waitMsec for all
177    the threads to finish whatever they're doing.  If waitMsec is -1, wait
178    as long as required.  If all the threads are done, free the port and return
179    0. Otherwise, return -1.  If you get a -1 return value, it is safe to call
180    this function again.
181*/
182EVENT2_EXPORT_SYMBOL
183int event_iocp_shutdown_(struct event_iocp_port *port, long waitMsec);
184
185/* FIXME document. */
186EVENT2_EXPORT_SYMBOL
187int event_iocp_activate_overlapped_(struct event_iocp_port *port,
188    struct event_overlapped *o,
189    ev_uintptr_t key, ev_uint32_t n_bytes);
190
191struct event_base;
192/* FIXME document. */
193EVENT2_EXPORT_SYMBOL
194struct event_iocp_port *event_base_get_iocp_(struct event_base *base);
195
196/* FIXME document. */
197EVENT2_EXPORT_SYMBOL
198int event_base_start_iocp_(struct event_base *base, int n_cpus);
199void event_base_stop_iocp_(struct event_base *base);
200
201/* FIXME document. */
202EVENT2_EXPORT_SYMBOL
203struct bufferevent *bufferevent_async_new_(struct event_base *base,
204    evutil_socket_t fd, int options);
205
206/* FIXME document. */
207void bufferevent_async_set_connected_(struct bufferevent *bev);
208int bufferevent_async_can_connect_(struct bufferevent *bev);
209int bufferevent_async_connect_(struct bufferevent *bev, evutil_socket_t fd,
210	const struct sockaddr *sa, int socklen);
211
212#ifdef __cplusplus
213}
214#endif
215
216#endif
217