libevent: event2/thread.h Source File

libevent 2.1.12 Event notification library

thread.h
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1/*
2 * Copyright (c) 2008-2012 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#ifndef EVENT2_THREAD_H_INCLUDED_
27#define EVENT2_THREAD_H_INCLUDED_
28
49#include <event2/visibility.h>
50
51#ifdef __cplusplus
52extern "C" {
53#endif
54
55#include <event2/event-config.h>
56
64#define EVTHREAD_WRITE 0x04
67#define EVTHREAD_READ 0x08
71#define EVTHREAD_TRY 0x10
74#if !defined(EVENT__DISABLE_THREAD_SUPPORT) || defined(EVENT_IN_DOXYGEN_)
75
76#define EVTHREAD_LOCK_API_VERSION 1
77
85#define EVTHREAD_LOCKTYPE_RECURSIVE 1
86/* A read-write lock is one that allows multiple simultaneous readers, but
87 * where any one writer excludes all other writers and readers. */
88#define EVTHREAD_LOCKTYPE_READWRITE 2
95 struct evthread_lock_callbacks {
98 int lock_api_version;
106 unsigned supported_locktypes;
109 void *(*alloc)(unsigned locktype);
112 void (*free)(void *lock, unsigned locktype);
115 int (*lock)(unsigned mode, void *lock);
118 int (*unlock)(unsigned mode, void *lock);
119};
120
129EVENT2_EXPORT_SYMBOL
130 int evthread_set_lock_callbacks(const struct evthread_lock_callbacks *);
131
132#define EVTHREAD_CONDITION_API_VERSION 1
133
134struct timeval;
135
140 struct evthread_condition_callbacks {
143 int condition_api_version;
148 void *(*alloc_condition)(unsigned condtype);
150 void (*free_condition)(void *cond);
157 int (*signal_condition)(void *cond, int broadcast);
168 int (*wait_condition)(void *cond, void *lock,
169 const struct timeval *timeout);
170};
171
180EVENT2_EXPORT_SYMBOL
181 int evthread_set_condition_callbacks(
182 const struct evthread_condition_callbacks *);
183
191EVENT2_EXPORT_SYMBOL
192 void evthread_set_id_callback(
193 unsigned long (*id_fn)(void));
194
195#if (defined(_WIN32) && !defined(EVENT__DISABLE_THREAD_SUPPORT)) || defined(EVENT_IN_DOXYGEN_)
200EVENT2_EXPORT_SYMBOL
201 int evthread_use_windows_threads(void);
205#define EVTHREAD_USE_WINDOWS_THREADS_IMPLEMENTED 1
206#endif
207
208#if defined(EVENT__HAVE_PTHREADS) || defined(EVENT_IN_DOXYGEN_)
214EVENT2_EXPORT_SYMBOL
215 int evthread_use_pthreads(void);
217#define EVTHREAD_USE_PTHREADS_IMPLEMENTED 1
218
219#endif
220
227EVENT2_EXPORT_SYMBOL
228 void evthread_enable_lock_debugging(void);
229
230/* Old (misspelled) version: This is deprecated; use
231 * evthread_enable_log_debugging instead. */
232EVENT2_EXPORT_SYMBOL
233void evthread_enable_lock_debuging(void);
234
235#endif /* EVENT__DISABLE_THREAD_SUPPORT */
236
237struct event_base;
246EVENT2_EXPORT_SYMBOL
247 int evthread_make_base_notifiable(struct event_base *base);
248
249#ifdef __cplusplus
250}
251#endif
252
253#endif /* EVENT2_THREAD_H_INCLUDED_ */
event_base
Structure to hold information and state for a Libevent dispatch loop.
Definition: event.h:219
evthread_condition_callbacks
This structure describes the interface a threading library uses for condition variables.
Definition: thread.h:140
evthread_condition_callbacks::signal_condition
int(* signal_condition)(void *cond, int broadcast)
Function to signal a condition variable.
Definition: thread.h:157
evthread_condition_callbacks::condition_api_version
int condition_api_version
The current version of the conditions API.
Definition: thread.h:143
evthread_condition_callbacks::wait_condition
int(* wait_condition)(void *cond, void *lock, const struct timeval *timeout)
Function to wait for a condition variable.
Definition: thread.h:168
evthread_condition_callbacks::free_condition
void(* free_condition)(void *cond)
Function to free a condition variable.
Definition: thread.h:150
evthread_lock_callbacks
This structure describes the interface a threading library uses for locking.
Definition: thread.h:95
evthread_lock_callbacks::lock
int(* lock)(unsigned mode, void *lock)
Acquire an already-allocated lock at 'lock' with mode 'mode'.
Definition: thread.h:115
evthread_lock_callbacks::unlock
int(* unlock)(unsigned mode, void *lock)
Release a lock at 'lock' using mode 'mode'.
Definition: thread.h:118
evthread_lock_callbacks::free
void(* free)(void *lock, unsigned locktype)
Funtion to release all storage held in 'lock', which was created with type 'locktype'.
Definition: thread.h:112
evthread_lock_callbacks::lock_api_version
int lock_api_version
The current version of the locking API.
Definition: thread.h:98
evthread_lock_callbacks::supported_locktypes
unsigned supported_locktypes
Which kinds of locks does this version of the locking API support? A bitfield of EVTHREAD_LOCKTYPE_RE...
Definition: thread.h:106
evthread_set_condition_callbacks
EVENT2_EXPORT_SYMBOL int evthread_set_condition_callbacks(const struct evthread_condition_callbacks *)
Sets a group of functions that Libevent should use for condition variables.
evthread_use_windows_threads
EVENT2_EXPORT_SYMBOL int evthread_use_windows_threads(void)
Sets up Libevent for use with Windows builtin locking and thread ID functions.
evthread_enable_lock_debugging
EVENT2_EXPORT_SYMBOL void evthread_enable_lock_debugging(void)
Enable debugging wrappers around the current lock callbacks.
evthread_set_id_callback
EVENT2_EXPORT_SYMBOL void evthread_set_id_callback(unsigned long(*id_fn)(void))
Sets the function for determining the thread id.
evthread_make_base_notifiable
EVENT2_EXPORT_SYMBOL int evthread_make_base_notifiable(struct event_base *base)
Make sure it's safe to tell an event base to wake up from another thread or a signal handler.
evthread_use_pthreads
EVENT2_EXPORT_SYMBOL int evthread_use_pthreads(void)
Sets up Libevent for use with Pthreads locking and thread ID functions.
evthread_set_lock_callbacks
EVENT2_EXPORT_SYMBOL int evthread_set_lock_callbacks(const struct evthread_lock_callbacks *)
Sets a group of functions that Libevent should use for locking.