the begginning

versioning/BRM/copylocks.h

@@ -0,0 +1,148 @@
+/* Copyright (C) 2014 InfiniDB, Inc.
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License
+   as published by the Free Software Foundation; version 2 of
+   the License.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+   MA 02110-1301, USA. */
+
+/******************************************************************************
+ * $Id: copylocks.h 1936 2013-07-09 22:10:29Z dhall $
+ *
+ *****************************************************************************/
+
+/** @file 
+ * class XXX interface
+ */
+ 
+#ifndef COPYLOCKS_H_
+#define COPYLOCKS_H_
+
+#include <set>
+#include <sys/types.h>
+//#define NDEBUG
+#include <cassert>
+
+#include <boost/thread.hpp>
+#include <boost/interprocess/shared_memory_object.hpp>
+#include <boost/interprocess/mapped_region.hpp>
+
+#include "brmtypes.h"
+#include "mastersegmenttable.h"
+
+#include "shmkeys.h"
+#include "undoable.h"
+
+#include "brmshmimpl.h"
+
+/* Should load these from a config file */
+#define CL_INITIAL_SIZE (50*sizeof(CopyLockEntry))
+#define CL_INCREMENT (50*sizeof(CopyLockEntry))
+
+#if defined(_MSC_VER) && defined(xxxCOPYLOCKS_DLLEXPORT)
+#define EXPORT __declspec(dllexport)
+#else
+#define EXPORT
+#endif
+
+
+namespace idbdatafile {
+class IDBDataFile;
+}
+
+namespace BRM {
+
+struct CopyLockEntry {
+	LBID_t start;
+	int size;
+	VER_t txnID;
+	EXPORT CopyLockEntry();
+};
+
+class CopyLocksImpl
+{
+public:
+	static CopyLocksImpl* makeCopyLocksImpl(unsigned key, off_t size, bool readOnly=false);
+
+	inline void grow(unsigned key, off_t size)
+#ifdef NDEBUG
+		{ fCopyLocks.grow(key, size); }
+#else
+		{ int rc=fCopyLocks.grow(key, size); idbassert(rc==0); }
+#endif
+	inline void makeReadOnly() { fCopyLocks.setReadOnly(); }
+	inline void clear(unsigned key, off_t size) { fCopyLocks.clear(key, size); }
+	inline void swapout(BRMShmImpl& rhs) { fCopyLocks.swap(rhs); rhs.destroy(); }
+	inline unsigned key() const { return fCopyLocks.key(); }
+
+	inline CopyLockEntry* get() const { return reinterpret_cast<CopyLockEntry*>(fCopyLocks.fMapreg.get_address()); }
+
+private:
+	CopyLocksImpl(unsigned key, off_t size, bool readOnly=false);
+	~CopyLocksImpl();
+	CopyLocksImpl(const CopyLocksImpl& rhs);
+	CopyLocksImpl& operator=(const CopyLocksImpl& rhs);
+
+	BRMShmImpl fCopyLocks;
+
+	static boost::mutex fInstanceMutex;
+	static CopyLocksImpl* fInstance;
+};
+
+class CopyLocks : public Undoable {
+	public:
+		
+		enum OPS {
+			NONE,
+			READ,
+			WRITE
+		};
+		
+		EXPORT CopyLocks();
+		EXPORT ~CopyLocks();
+		
+		EXPORT void lockRange(const LBIDRange& range, VER_t txnID);
+		EXPORT void releaseRange(const LBIDRange& range);
+		EXPORT bool isLocked(const LBIDRange& range) const;
+		EXPORT void rollback(VER_t txnID);
+		
+		EXPORT void lock(OPS op);
+		EXPORT void release(OPS op);
+		EXPORT void setReadOnly();
+		EXPORT void getCurrentTxnIDs(std::set<VER_t> &txnList) const;
+
+		EXPORT void forceRelease(const LBIDRange &range);
+
+	private:
+		CopyLocks(const CopyLocks &);
+		CopyLocks& operator=(const CopyLocks &);
+		
+		key_t chooseShmkey();
+		void growCL();
+		
+		CopyLockEntry* entries;
+		key_t currentShmkey;
+		int shmid;    //shmid's necessary?
+		MSTEntry* shminfo;
+		MasterSegmentTable mst;
+		bool r_only;
+		static boost::mutex mutex;
+		static const int MAX_IO_RETRIES=10;
+		ShmKeys fShmKeys;
+		CopyLocksImpl* fCopyLocksImpl;
+};
+
+} 
+
+#undef EXPORT
+
+#endif