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+// Copyright (c) 2009-2010 Satoshi Nakamoto
+// Copyright (c) 2009-2012 The Bitcoin developers
+// Distributed under the MIT/X11 software license, see the accompanying
+// file license.txt or http://www.opensource.org/licenses/mit-license.php.
+#ifndef BITCOIN_SYNC_H
+#define BITCOIN_SYNC_H
+
+#include <boost/interprocess/sync/interprocess_recursive_mutex.hpp>
+#include <boost/interprocess/sync/scoped_lock.hpp>
+#include <boost/interprocess/sync/interprocess_semaphore.hpp>
+#include <boost/interprocess/sync/lock_options.hpp>
+
+
+
+
+/** Wrapped boost mutex: supports recursive locking, but no waiting */
+typedef boost::interprocess::interprocess_recursive_mutex CCriticalSection;
+
+/** Wrapped boost mutex: supports waiting but not recursive locking */
+typedef boost::interprocess::interprocess_mutex CWaitableCriticalSection;
+
+#ifdef DEBUG_LOCKORDER
+void EnterCritical(const char* pszName, const char* pszFile, int nLine, void* cs, bool fTry = false);
+void LeaveCritical();
+#else
+void static inline EnterCritical(const char* pszName, const char* pszFile, int nLine, void* cs, bool fTry = false) {}
+void static inline LeaveCritical() {}
+#endif
+
+/** Wrapper around boost::interprocess::scoped_lock */
+template<typename Mutex>
+class CMutexLock
+{
+private:
+ boost::interprocess::scoped_lock<Mutex> lock;
+public:
+
+ void Enter(const char* pszName, const char* pszFile, int nLine)
+ {
+ if (!lock.owns())
+ {
+ EnterCritical(pszName, pszFile, nLine, (void*)(lock.mutex()));
+#ifdef DEBUG_LOCKCONTENTION
+ if (!lock.try_lock())
+ {
+ printf("LOCKCONTENTION: %s\n", pszName);
+ printf("Locker: %s:%d\n", pszFile, nLine);
+#endif
+ lock.lock();
+#ifdef DEBUG_LOCKCONTENTION
+ }
+#endif
+ }
+ }
+
+ void Leave()
+ {
+ if (lock.owns())
+ {
+ lock.unlock();
+ LeaveCritical();
+ }
+ }
+
+ bool TryEnter(const char* pszName, const char* pszFile, int nLine)
+ {
+ if (!lock.owns())
+ {
+ EnterCritical(pszName, pszFile, nLine, (void*)(lock.mutex()), true);
+ lock.try_lock();
+ if (!lock.owns())
+ LeaveCritical();
+ }
+ return lock.owns();
+ }
+
+ CMutexLock(Mutex& mutexIn, const char* pszName, const char* pszFile, int nLine, bool fTry = false) : lock(mutexIn, boost::interprocess::defer_lock)
+ {
+ if (fTry)
+ TryEnter(pszName, pszFile, nLine);
+ else
+ Enter(pszName, pszFile, nLine);
+ }
+
+ ~CMutexLock()
+ {
+ if (lock.owns())
+ LeaveCritical();
+ }
+
+ operator bool()
+ {
+ return lock.owns();
+ }
+
+ boost::interprocess::scoped_lock<Mutex> &GetLock()
+ {
+ return lock;
+ }
+};
+
+typedef CMutexLock<CCriticalSection> CCriticalBlock;
+
+#define LOCK(cs) CCriticalBlock criticalblock(cs, #cs, __FILE__, __LINE__)
+#define LOCK2(cs1,cs2) CCriticalBlock criticalblock1(cs1, #cs1, __FILE__, __LINE__),criticalblock2(cs2, #cs2, __FILE__, __LINE__)
+#define TRY_LOCK(cs,name) CCriticalBlock name(cs, #cs, __FILE__, __LINE__, true)
+
+#define ENTER_CRITICAL_SECTION(cs) \
+ { \
+ EnterCritical(#cs, __FILE__, __LINE__, (void*)(&cs)); \
+ (cs).lock(); \
+ }
+
+#define LEAVE_CRITICAL_SECTION(cs) \
+ { \
+ (cs).unlock(); \
+ LeaveCritical(); \
+ }
+
+#ifdef MAC_OSX
+// boost::interprocess::interprocess_semaphore seems to spinlock on OSX; prefer polling instead
+class CSemaphore
+{
+private:
+ CCriticalSection cs;
+ int val;
+
+public:
+ CSemaphore(int init) : val(init) {}
+
+ void wait() {
+ do {
+ {
+ LOCK(cs);
+ if (val>0) {
+ val--;
+ return;
+ }
+ }
+ Sleep(100);
+ } while(1);
+ }
+
+ bool try_wait() {
+ LOCK(cs);
+ if (val>0) {
+ val--;
+ return true;
+ }
+ return false;
+ }
+
+ void post() {
+ LOCK(cs);
+ val++;
+ }
+};
+#else
+typedef boost::interprocess::interprocess_semaphore CSemaphore;
+#endif
+
+/** RAII-style semaphore lock */
+class CSemaphoreGrant
+{
+private:
+ CSemaphore *sem;
+ bool fHaveGrant;
+
+public:
+ void Acquire() {
+ if (fHaveGrant)
+ return;
+ sem->wait();
+ fHaveGrant = true;
+ }
+
+ void Release() {
+ if (!fHaveGrant)
+ return;
+ sem->post();
+ fHaveGrant = false;
+ }
+
+ bool TryAcquire() {
+ if (!fHaveGrant && sem->try_wait())
+ fHaveGrant = true;
+ return fHaveGrant;
+ }
+
+ void MoveTo(CSemaphoreGrant &grant) {
+ grant.Release();
+ grant.sem = sem;
+ grant.fHaveGrant = fHaveGrant;
+ sem = NULL;
+ fHaveGrant = false;
+ }
+
+ CSemaphoreGrant() : sem(NULL), fHaveGrant(false) {}
+
+ CSemaphoreGrant(CSemaphore &sema, bool fTry = false) : sem(&sema), fHaveGrant(false) {
+ if (fTry)
+ TryAcquire();
+ else
+ Acquire();
+ }
+
+ ~CSemaphoreGrant() {
+ Release();
+ }
+
+ operator bool() {
+ return fHaveGrant;
+ }
+};
+#endif
+