monero/external/unbound/util/locks.h
Erik de Castro Lopo a85b5759f3 Upgrade unbound library
These files were pulled from the 1.6.3 release tarball.

This new version builds against OpenSSL version 1.1 which will be
the default in the new Debian Stable which is due to be released
RealSoonNow (tm).
2017-06-17 23:04:00 +10:00

313 lines
12 KiB
C

/**
* util/locks.h - unbound locking primitives
*
* Copyright (c) 2007, NLnet Labs. All rights reserved.
*
* This software is open source.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 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.
*
* Neither the name of the NLNET LABS nor the names of its contributors may
* be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "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 COPYRIGHT
* HOLDER OR CONTRIBUTORS 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 UTIL_LOCKS_H
#define UTIL_LOCKS_H
/**
* \file
* Locking primitives.
* If pthreads is available, these are used.
* If no locking exists, they do nothing.
*
* The idea is to have different sorts of locks for different tasks.
* This allows the locking code to be ported more easily.
*
* Types of locks that are supported.
* o lock_rw: lock that has many readers and one writer (to a data entry).
* o lock_basic: simple mutex. Blocking, one person has access only.
* This lock is meant for non performance sensitive uses.
* o lock_quick: speed lock. For performance sensitive locking of critical
* sections. Could be implemented by a mutex or a spinlock.
*
* Also thread creation and deletion functions are defined here.
*/
/* if you define your own LOCKRET before including locks.h, you can get most
* locking functions without the dependency on log_err. */
#ifndef LOCKRET
#include "util/log.h"
/**
* The following macro is used to check the return value of the
* pthread calls. They return 0 on success and an errno on error.
* The errno is logged to the logfile with a descriptive comment.
*/
#define LOCKRET(func) do {\
int lockret_err; \
if( (lockret_err=(func)) != 0) \
log_err("%s at %d could not " #func ": %s", \
__FILE__, __LINE__, strerror(lockret_err)); \
} while(0)
#endif
/** DEBUG: use thread debug whenever possible */
#if defined(HAVE_PTHREAD) && defined(HAVE_PTHREAD_SPINLOCK_T) && defined(ENABLE_LOCK_CHECKS)
# define USE_THREAD_DEBUG
#endif
#ifdef USE_THREAD_DEBUG
/******************* THREAD DEBUG ************************/
/* (some) checking; to detect races and deadlocks. */
#include "testcode/checklocks.h"
#else /* USE_THREAD_DEBUG */
#define lock_protect(lock, area, size) /* nop */
#define lock_unprotect(lock, area) /* nop */
#define lock_get_mem(lock) (0) /* nothing */
#define checklock_start() /* nop */
#define checklock_stop() /* nop */
#ifdef HAVE_PTHREAD
#include <pthread.h>
/******************* PTHREAD ************************/
/** use pthread mutex for basic lock */
typedef pthread_mutex_t lock_basic_type;
/** small front for pthread init func, NULL is default attrs. */
#define lock_basic_init(lock) LOCKRET(pthread_mutex_init(lock, NULL))
#define lock_basic_destroy(lock) LOCKRET(pthread_mutex_destroy(lock))
#define lock_basic_lock(lock) LOCKRET(pthread_mutex_lock(lock))
#define lock_basic_unlock(lock) LOCKRET(pthread_mutex_unlock(lock))
#ifndef HAVE_PTHREAD_RWLOCK_T
/** in case rwlocks are not supported, use a mutex. */
typedef pthread_mutex_t lock_rw_type;
#define lock_rw_init(lock) LOCKRET(pthread_mutex_init(lock, NULL))
#define lock_rw_destroy(lock) LOCKRET(pthread_mutex_destroy(lock))
#define lock_rw_rdlock(lock) LOCKRET(pthread_mutex_lock(lock))
#define lock_rw_wrlock(lock) LOCKRET(pthread_mutex_lock(lock))
#define lock_rw_unlock(lock) LOCKRET(pthread_mutex_unlock(lock))
#else /* HAVE_PTHREAD_RWLOCK_T */
/** we use the pthread rwlock */
typedef pthread_rwlock_t lock_rw_type;
/** small front for pthread init func, NULL is default attrs. */
#define lock_rw_init(lock) LOCKRET(pthread_rwlock_init(lock, NULL))
#define lock_rw_destroy(lock) LOCKRET(pthread_rwlock_destroy(lock))
#define lock_rw_rdlock(lock) LOCKRET(pthread_rwlock_rdlock(lock))
#define lock_rw_wrlock(lock) LOCKRET(pthread_rwlock_wrlock(lock))
#define lock_rw_unlock(lock) LOCKRET(pthread_rwlock_unlock(lock))
#endif /* HAVE_PTHREAD_RWLOCK_T */
#ifndef HAVE_PTHREAD_SPINLOCK_T
/** in case spinlocks are not supported, use a mutex. */
typedef pthread_mutex_t lock_quick_type;
/** small front for pthread init func, NULL is default attrs. */
#define lock_quick_init(lock) LOCKRET(pthread_mutex_init(lock, NULL))
#define lock_quick_destroy(lock) LOCKRET(pthread_mutex_destroy(lock))
#define lock_quick_lock(lock) LOCKRET(pthread_mutex_lock(lock))
#define lock_quick_unlock(lock) LOCKRET(pthread_mutex_unlock(lock))
#else /* HAVE_PTHREAD_SPINLOCK_T */
/** use pthread spinlock for the quick lock */
typedef pthread_spinlock_t lock_quick_type;
/**
* allocate process private since this is available whether
* Thread Process-Shared Synchronization is supported or not.
* This means only threads inside this process may access the lock.
* (not threads from another process that shares memory).
* spinlocks are not supported on all pthread platforms.
*/
#define lock_quick_init(lock) LOCKRET(pthread_spin_init(lock, PTHREAD_PROCESS_PRIVATE))
#define lock_quick_destroy(lock) LOCKRET(pthread_spin_destroy(lock))
#define lock_quick_lock(lock) LOCKRET(pthread_spin_lock(lock))
#define lock_quick_unlock(lock) LOCKRET(pthread_spin_unlock(lock))
#endif /* HAVE SPINLOCK */
/** Thread creation */
typedef pthread_t ub_thread_type;
/** On alpine linux default thread stack size is 80 Kb. See
http://wiki.musl-libc.org/wiki/Functional_differences_from_glibc#Thread_stack_size
This is not enough and cause segfault. Other linux distros have 2 Mb at least.
Wrapper for set up thread stack size */
#define PTHREADSTACKSIZE 2*1024*1024
#define PTHREADCREATE(thr, stackrequired, func, arg) do {\
pthread_attr_t attr; \
size_t stacksize; \
LOCKRET(pthread_attr_init(&attr)); \
LOCKRET(pthread_attr_getstacksize(&attr, &stacksize)); \
if (stacksize < stackrequired) { \
LOCKRET(pthread_attr_setstacksize(&attr, stackrequired)); \
LOCKRET(pthread_create(thr, &attr, func, arg)); \
LOCKRET(pthread_attr_getstacksize(&attr, &stacksize)); \
verbose(VERB_ALGO, "Thread stack size set to %u", (unsigned)stacksize); \
} else {LOCKRET(pthread_create(thr, NULL, func, arg));} \
} while(0)
/** Use wrapper for set thread stack size on attributes. */
#define ub_thread_create(thr, func, arg) PTHREADCREATE(thr, PTHREADSTACKSIZE, func, arg)
/** get self id. */
#define ub_thread_self() pthread_self()
/** wait for another thread to terminate */
#define ub_thread_join(thread) LOCKRET(pthread_join(thread, NULL))
typedef pthread_key_t ub_thread_key_type;
#define ub_thread_key_create(key, f) LOCKRET(pthread_key_create(key, f))
#define ub_thread_key_set(key, v) LOCKRET(pthread_setspecific(key, v))
#define ub_thread_key_get(key) pthread_getspecific(key)
#else /* we do not HAVE_PTHREAD */
#ifdef HAVE_SOLARIS_THREADS
/******************* SOLARIS THREADS ************************/
#include <synch.h>
#include <thread.h>
typedef rwlock_t lock_rw_type;
#define lock_rw_init(lock) LOCKRET(rwlock_init(lock, USYNC_THREAD, NULL))
#define lock_rw_destroy(lock) LOCKRET(rwlock_destroy(lock))
#define lock_rw_rdlock(lock) LOCKRET(rw_rdlock(lock))
#define lock_rw_wrlock(lock) LOCKRET(rw_wrlock(lock))
#define lock_rw_unlock(lock) LOCKRET(rw_unlock(lock))
/** use basic mutex */
typedef mutex_t lock_basic_type;
#define lock_basic_init(lock) LOCKRET(mutex_init(lock, USYNC_THREAD, NULL))
#define lock_basic_destroy(lock) LOCKRET(mutex_destroy(lock))
#define lock_basic_lock(lock) LOCKRET(mutex_lock(lock))
#define lock_basic_unlock(lock) LOCKRET(mutex_unlock(lock))
/** No spinlocks in solaris threads API. Use a mutex. */
typedef mutex_t lock_quick_type;
#define lock_quick_init(lock) LOCKRET(mutex_init(lock, USYNC_THREAD, NULL))
#define lock_quick_destroy(lock) LOCKRET(mutex_destroy(lock))
#define lock_quick_lock(lock) LOCKRET(mutex_lock(lock))
#define lock_quick_unlock(lock) LOCKRET(mutex_unlock(lock))
/** Thread creation, create a default thread. */
typedef thread_t ub_thread_type;
#define ub_thread_create(thr, func, arg) LOCKRET(thr_create(NULL, NULL, func, arg, NULL, thr))
#define ub_thread_self() thr_self()
#define ub_thread_join(thread) LOCKRET(thr_join(thread, NULL, NULL))
typedef thread_key_t ub_thread_key_type;
#define ub_thread_key_create(key, f) LOCKRET(thr_keycreate(key, f))
#define ub_thread_key_set(key, v) LOCKRET(thr_setspecific(key, v))
void* ub_thread_key_get(ub_thread_key_type key);
#else /* we do not HAVE_SOLARIS_THREADS and no PTHREADS */
/******************* WINDOWS THREADS ************************/
#ifdef HAVE_WINDOWS_THREADS
#include <windows.h>
/* Use a mutex */
typedef LONG lock_rw_type;
#define lock_rw_init(lock) lock_basic_init(lock)
#define lock_rw_destroy(lock) lock_basic_destroy(lock)
#define lock_rw_rdlock(lock) lock_basic_lock(lock)
#define lock_rw_wrlock(lock) lock_basic_lock(lock)
#define lock_rw_unlock(lock) lock_basic_unlock(lock)
/** the basic lock is a mutex, implemented opaquely, for error handling. */
typedef LONG lock_basic_type;
void lock_basic_init(lock_basic_type* lock);
void lock_basic_destroy(lock_basic_type* lock);
void lock_basic_lock(lock_basic_type* lock);
void lock_basic_unlock(lock_basic_type* lock);
/** on windows no spinlock, use mutex too. */
typedef LONG lock_quick_type;
#define lock_quick_init(lock) lock_basic_init(lock)
#define lock_quick_destroy(lock) lock_basic_destroy(lock)
#define lock_quick_lock(lock) lock_basic_lock(lock)
#define lock_quick_unlock(lock) lock_basic_unlock(lock)
/** Thread creation, create a default thread. */
typedef HANDLE ub_thread_type;
void ub_thread_create(ub_thread_type* thr, void* (*func)(void*), void* arg);
ub_thread_type ub_thread_self(void);
void ub_thread_join(ub_thread_type thr);
typedef DWORD ub_thread_key_type;
void ub_thread_key_create(ub_thread_key_type* key, void* f);
void ub_thread_key_set(ub_thread_key_type key, void* v);
void* ub_thread_key_get(ub_thread_key_type key);
#else /* we do not HAVE_SOLARIS_THREADS, PTHREADS or WINDOWS_THREADS */
/******************* NO THREADS ************************/
#define THREADS_DISABLED 1
/** In case there is no thread support, define locks to do nothing */
typedef int lock_rw_type;
#define lock_rw_init(lock) /* nop */
#define lock_rw_destroy(lock) /* nop */
#define lock_rw_rdlock(lock) /* nop */
#define lock_rw_wrlock(lock) /* nop */
#define lock_rw_unlock(lock) /* nop */
/** define locks to do nothing */
typedef int lock_basic_type;
#define lock_basic_init(lock) /* nop */
#define lock_basic_destroy(lock) /* nop */
#define lock_basic_lock(lock) /* nop */
#define lock_basic_unlock(lock) /* nop */
/** define locks to do nothing */
typedef int lock_quick_type;
#define lock_quick_init(lock) /* nop */
#define lock_quick_destroy(lock) /* nop */
#define lock_quick_lock(lock) /* nop */
#define lock_quick_unlock(lock) /* nop */
/** Thread creation, threads do not exist */
typedef pid_t ub_thread_type;
/** ub_thread_create is simulated with fork (extremely heavy threads,
* with no shared memory). */
#define ub_thread_create(thr, func, arg) \
ub_thr_fork_create(thr, func, arg)
#define ub_thread_self() getpid()
#define ub_thread_join(thread) ub_thr_fork_wait(thread)
void ub_thr_fork_wait(ub_thread_type thread);
void ub_thr_fork_create(ub_thread_type* thr, void* (*func)(void*), void* arg);
typedef void* ub_thread_key_type;
#define ub_thread_key_create(key, f) (*(key)) = NULL
#define ub_thread_key_set(key, v) (key) = (v)
#define ub_thread_key_get(key) (key)
#endif /* HAVE_WINDOWS_THREADS */
#endif /* HAVE_SOLARIS_THREADS */
#endif /* HAVE_PTHREAD */
#endif /* USE_THREAD_DEBUG */
/**
* Block all signals for this thread.
* fatal exit on error.
*/
void ub_thread_blocksigs(void);
/**
* unblock one signal for this thread.
*/
void ub_thread_sig_unblock(int sig);
#endif /* UTIL_LOCKS_H */