Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
Fetching contributors…

Cannot retrieve contributors at this time

385 lines (334 sloc) 13.916 kb
/*
* Copyright (c) 2008-2012 Niels Provos, Nick Mathewson
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef EVTHREAD_INTERNAL_H_INCLUDED_
#define EVTHREAD_INTERNAL_H_INCLUDED_
#ifdef __cplusplus
extern "C" {
#endif
#include "event2/event-config.h"
#include "evconfig-private.h"
#include "event2/thread.h"
#include "util-internal.h"
struct event_base;
#ifndef _WIN32
/* On Windows, the way we currently make DLLs, it's not allowed for us to
* have shared global structures. Thus, we only do the direct-call-to-function
* code path if we know that the local shared library system supports it.
*/
#define EVTHREAD_EXPOSE_STRUCTS
#endif
#if ! defined(EVENT__DISABLE_THREAD_SUPPORT) && defined(EVTHREAD_EXPOSE_STRUCTS)
/* Global function pointers to lock-related functions. NULL if locking isn't
enabled. */
extern struct evthread_lock_callbacks evthread_lock_fns_;
extern struct evthread_condition_callbacks evthread_cond_fns_;
extern unsigned long (*evthread_id_fn_)(void);
extern int evthread_lock_debugging_enabled_;
/** Return the ID of the current thread, or 1 if threading isn't enabled. */
#define EVTHREAD_GET_ID() \
(evthread_id_fn_ ? evthread_id_fn_() : 1)
/** Return true iff we're in the thread that is currently (or most recently)
* running a given event_base's loop. Requires lock. */
#define EVBASE_IN_THREAD(base) \
(evthread_id_fn_ == NULL || \
(base)->th_owner_id == evthread_id_fn_())
/** Return true iff we need to notify the base's main thread about changes to
* its state, because it's currently running the main loop in another
* thread. Requires lock. */
#define EVBASE_NEED_NOTIFY(base) \
(evthread_id_fn_ != NULL && \
(base)->running_loop && \
(base)->th_owner_id != evthread_id_fn_())
/** Allocate a new lock, and store it in lockvar, a void*. Sets lockvar to
NULL if locking is not enabled. */
#define EVTHREAD_ALLOC_LOCK(lockvar, locktype) \
((lockvar) = evthread_lock_fns_.alloc ? \
evthread_lock_fns_.alloc(locktype) : NULL)
/** Free a given lock, if it is present and locking is enabled. */
#define EVTHREAD_FREE_LOCK(lockvar, locktype) \
do { \
void *lock_tmp_ = (lockvar); \
if (lock_tmp_ && evthread_lock_fns_.free) \
evthread_lock_fns_.free(lock_tmp_, (locktype)); \
} while (0)
/** Acquire a lock. */
#define EVLOCK_LOCK(lockvar,mode) \
do { \
if (lockvar) \
evthread_lock_fns_.lock(mode, lockvar); \
} while (0)
/** Release a lock */
#define EVLOCK_UNLOCK(lockvar,mode) \
do { \
if (lockvar) \
evthread_lock_fns_.unlock(mode, lockvar); \
} while (0)
/** Helper: put lockvar1 and lockvar2 into pointerwise ascending order. */
#define EVLOCK_SORTLOCKS_(lockvar1, lockvar2) \
do { \
if (lockvar1 && lockvar2 && lockvar1 > lockvar2) { \
void *tmp = lockvar1; \
lockvar1 = lockvar2; \
lockvar2 = tmp; \
} \
} while (0)
/** Lock an event_base, if it is set up for locking. Acquires the lock
in the base structure whose field is named 'lockvar'. */
#define EVBASE_ACQUIRE_LOCK(base, lockvar) do { \
EVLOCK_LOCK((base)->lockvar, 0); \
} while (0)
/** Unlock an event_base, if it is set up for locking. */
#define EVBASE_RELEASE_LOCK(base, lockvar) do { \
EVLOCK_UNLOCK((base)->lockvar, 0); \
} while (0)
/** If lock debugging is enabled, and lock is non-null, assert that 'lock' is
* locked and held by us. */
#define EVLOCK_ASSERT_LOCKED(lock) \
do { \
if ((lock) && evthread_lock_debugging_enabled_) { \
EVUTIL_ASSERT(evthread_is_debug_lock_held_(lock)); \
} \
} while (0)
/** Try to grab the lock for 'lockvar' without blocking, and return 1 if we
* manage to get it. */
static inline int EVLOCK_TRY_LOCK_(void *lock);
static inline int
EVLOCK_TRY_LOCK_(void *lock)
{
if (lock && evthread_lock_fns_.lock) {
int r = evthread_lock_fns_.lock(EVTHREAD_TRY, lock);
return !r;
} else {
/* Locking is disabled either globally or for this thing;
* of course we count as having the lock. */
return 1;
}
}
/** Allocate a new condition variable and store it in the void *, condvar */
#define EVTHREAD_ALLOC_COND(condvar) \
do { \
(condvar) = evthread_cond_fns_.alloc_condition ? \
evthread_cond_fns_.alloc_condition(0) : NULL; \
} while (0)
/** Deallocate and free a condition variable in condvar */
#define EVTHREAD_FREE_COND(cond) \
do { \
if (cond) \
evthread_cond_fns_.free_condition((cond)); \
} while (0)
/** Signal one thread waiting on cond */
#define EVTHREAD_COND_SIGNAL(cond) \
( (cond) ? evthread_cond_fns_.signal_condition((cond), 0) : 0 )
/** Signal all threads waiting on cond */
#define EVTHREAD_COND_BROADCAST(cond) \
( (cond) ? evthread_cond_fns_.signal_condition((cond), 1) : 0 )
/** Wait until the condition 'cond' is signalled. Must be called while
* holding 'lock'. The lock will be released until the condition is
* signalled, at which point it will be acquired again. Returns 0 for
* success, -1 for failure. */
#define EVTHREAD_COND_WAIT(cond, lock) \
( (cond) ? evthread_cond_fns_.wait_condition((cond), (lock), NULL) : 0 )
/** As EVTHREAD_COND_WAIT, but gives up after 'tv' has elapsed. Returns 1
* on timeout. */
#define EVTHREAD_COND_WAIT_TIMED(cond, lock, tv) \
( (cond) ? evthread_cond_fns_.wait_condition((cond), (lock), (tv)) : 0 )
/** True iff locking functions have been configured. */
#define EVTHREAD_LOCKING_ENABLED() \
(evthread_lock_fns_.lock != NULL)
#elif ! defined(EVENT__DISABLE_THREAD_SUPPORT)
unsigned long evthreadimpl_get_id_(void);
int evthreadimpl_is_lock_debugging_enabled_(void);
void *evthreadimpl_lock_alloc_(unsigned locktype);
void evthreadimpl_lock_free_(void *lock, unsigned locktype);
int evthreadimpl_lock_lock_(unsigned mode, void *lock);
int evthreadimpl_lock_unlock_(unsigned mode, void *lock);
void *evthreadimpl_cond_alloc_(unsigned condtype);
void evthreadimpl_cond_free_(void *cond);
int evthreadimpl_cond_signal_(void *cond, int broadcast);
int evthreadimpl_cond_wait_(void *cond, void *lock, const struct timeval *tv);
int evthreadimpl_locking_enabled_(void);
#define EVTHREAD_GET_ID() evthreadimpl_get_id_()
#define EVBASE_IN_THREAD(base) \
((base)->th_owner_id == evthreadimpl_get_id_())
#define EVBASE_NEED_NOTIFY(base) \
((base)->running_loop && \
((base)->th_owner_id != evthreadimpl_get_id_()))
#define EVTHREAD_ALLOC_LOCK(lockvar, locktype) \
((lockvar) = evthreadimpl_lock_alloc_(locktype))
#define EVTHREAD_FREE_LOCK(lockvar, locktype) \
do { \
void *lock_tmp_ = (lockvar); \
if (lock_tmp_) \
evthreadimpl_lock_free_(lock_tmp_, (locktype)); \
} while (0)
/** Acquire a lock. */
#define EVLOCK_LOCK(lockvar,mode) \
do { \
if (lockvar) \
evthreadimpl_lock_lock_(mode, lockvar); \
} while (0)
/** Release a lock */
#define EVLOCK_UNLOCK(lockvar,mode) \
do { \
if (lockvar) \
evthreadimpl_lock_unlock_(mode, lockvar); \
} while (0)
/** Lock an event_base, if it is set up for locking. Acquires the lock
in the base structure whose field is named 'lockvar'. */
#define EVBASE_ACQUIRE_LOCK(base, lockvar) do { \
EVLOCK_LOCK((base)->lockvar, 0); \
} while (0)
/** Unlock an event_base, if it is set up for locking. */
#define EVBASE_RELEASE_LOCK(base, lockvar) do { \
EVLOCK_UNLOCK((base)->lockvar, 0); \
} while (0)
/** If lock debugging is enabled, and lock is non-null, assert that 'lock' is
* locked and held by us. */
#define EVLOCK_ASSERT_LOCKED(lock) \
do { \
if ((lock) && evthreadimpl_is_lock_debugging_enabled_()) { \
EVUTIL_ASSERT(evthread_is_debug_lock_held_(lock)); \
} \
} while (0)
/** Try to grab the lock for 'lockvar' without blocking, and return 1 if we
* manage to get it. */
static inline int EVLOCK_TRY_LOCK_(void *lock);
static inline int
EVLOCK_TRY_LOCK_(void *lock)
{
if (lock) {
int r = evthreadimpl_lock_lock_(EVTHREAD_TRY, lock);
return !r;
} else {
/* Locking is disabled either globally or for this thing;
* of course we count as having the lock. */
return 1;
}
}
/** Allocate a new condition variable and store it in the void *, condvar */
#define EVTHREAD_ALLOC_COND(condvar) \
do { \
(condvar) = evthreadimpl_cond_alloc_(0); \
} while (0)
/** Deallocate and free a condition variable in condvar */
#define EVTHREAD_FREE_COND(cond) \
do { \
if (cond) \
evthreadimpl_cond_free_((cond)); \
} while (0)
/** Signal one thread waiting on cond */
#define EVTHREAD_COND_SIGNAL(cond) \
( (cond) ? evthreadimpl_cond_signal_((cond), 0) : 0 )
/** Signal all threads waiting on cond */
#define EVTHREAD_COND_BROADCAST(cond) \
( (cond) ? evthreadimpl_cond_signal_((cond), 1) : 0 )
/** Wait until the condition 'cond' is signalled. Must be called while
* holding 'lock'. The lock will be released until the condition is
* signalled, at which point it will be acquired again. Returns 0 for
* success, -1 for failure. */
#define EVTHREAD_COND_WAIT(cond, lock) \
( (cond) ? evthreadimpl_cond_wait_((cond), (lock), NULL) : 0 )
/** As EVTHREAD_COND_WAIT, but gives up after 'tv' has elapsed. Returns 1
* on timeout. */
#define EVTHREAD_COND_WAIT_TIMED(cond, lock, tv) \
( (cond) ? evthreadimpl_cond_wait_((cond), (lock), (tv)) : 0 )
#define EVTHREAD_LOCKING_ENABLED() \
(evthreadimpl_locking_enabled_())
#else /* EVENT__DISABLE_THREAD_SUPPORT */
#define EVTHREAD_GET_ID() 1
#define EVTHREAD_ALLOC_LOCK(lockvar, locktype) EVUTIL_NIL_STMT_
#define EVTHREAD_FREE_LOCK(lockvar, locktype) EVUTIL_NIL_STMT_
#define EVLOCK_LOCK(lockvar, mode) EVUTIL_NIL_STMT_
#define EVLOCK_UNLOCK(lockvar, mode) EVUTIL_NIL_STMT_
#define EVLOCK_LOCK2(lock1,lock2,mode1,mode2) EVUTIL_NIL_STMT_
#define EVLOCK_UNLOCK2(lock1,lock2,mode1,mode2) EVUTIL_NIL_STMT_
#define EVBASE_IN_THREAD(base) 1
#define EVBASE_NEED_NOTIFY(base) 0
#define EVBASE_ACQUIRE_LOCK(base, lock) EVUTIL_NIL_STMT_
#define EVBASE_RELEASE_LOCK(base, lock) EVUTIL_NIL_STMT_
#define EVLOCK_ASSERT_LOCKED(lock) EVUTIL_NIL_STMT_
#define EVLOCK_TRY_LOCK_(lock) 1
#define EVTHREAD_ALLOC_COND(condvar) EVUTIL_NIL_STMT_
#define EVTHREAD_FREE_COND(cond) EVUTIL_NIL_STMT_
#define EVTHREAD_COND_SIGNAL(cond) EVUTIL_NIL_STMT_
#define EVTHREAD_COND_BROADCAST(cond) EVUTIL_NIL_STMT_
#define EVTHREAD_COND_WAIT(cond, lock) EVUTIL_NIL_STMT_
#define EVTHREAD_COND_WAIT_TIMED(cond, lock, howlong) EVUTIL_NIL_STMT_
#define EVTHREAD_LOCKING_ENABLED() 0
#endif
/* This code is shared between both lock impls */
#if ! defined(EVENT__DISABLE_THREAD_SUPPORT)
/** Helper: put lockvar1 and lockvar2 into pointerwise ascending order. */
#define EVLOCK_SORTLOCKS_(lockvar1, lockvar2) \
do { \
if (lockvar1 && lockvar2 && lockvar1 > lockvar2) { \
void *tmp = lockvar1; \
lockvar1 = lockvar2; \
lockvar2 = tmp; \
} \
} while (0)
/** Acquire both lock1 and lock2. Always allocates locks in the same order,
* so that two threads locking two locks with LOCK2 will not deadlock. */
#define EVLOCK_LOCK2(lock1,lock2,mode1,mode2) \
do { \
void *lock1_tmplock_ = (lock1); \
void *lock2_tmplock_ = (lock2); \
EVLOCK_SORTLOCKS_(lock1_tmplock_,lock2_tmplock_); \
EVLOCK_LOCK(lock1_tmplock_,mode1); \
if (lock2_tmplock_ != lock1_tmplock_) \
EVLOCK_LOCK(lock2_tmplock_,mode2); \
} while (0)
/** Release both lock1 and lock2. */
#define EVLOCK_UNLOCK2(lock1,lock2,mode1,mode2) \
do { \
void *lock1_tmplock_ = (lock1); \
void *lock2_tmplock_ = (lock2); \
EVLOCK_SORTLOCKS_(lock1_tmplock_,lock2_tmplock_); \
if (lock2_tmplock_ != lock1_tmplock_) \
EVLOCK_UNLOCK(lock2_tmplock_,mode2); \
EVLOCK_UNLOCK(lock1_tmplock_,mode1); \
} while (0)
int evthread_is_debug_lock_held_(void *lock);
void *evthread_debug_get_real_lock_(void *lock);
void *evthread_setup_global_lock_(void *lock_, unsigned locktype,
int enable_locks);
#define EVTHREAD_SETUP_GLOBAL_LOCK(lockvar, locktype) \
do { \
lockvar = evthread_setup_global_lock_(lockvar, \
(locktype), enable_locks); \
if (!lockvar) { \
event_warn("Couldn't allocate %s", #lockvar); \
return -1; \
} \
} while (0);
int event_global_setup_locks_(const int enable_locks);
int evsig_global_setup_locks_(const int enable_locks);
int evutil_secure_rng_global_setup_locks_(const int enable_locks);
#endif
#ifdef __cplusplus
}
#endif
#endif /* EVTHREAD_INTERNAL_H_INCLUDED_ */
Jump to Line
Something went wrong with that request. Please try again.