include/Database.h

   1 /***************************************************************************
   2  *   Copyright (C) 2007 by www.databasecache.com                           *
   3  *   Contact: praba_tuty@databasecache.com                                 *
   4  *                                                                         *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15   ***************************************************************************/
  16 #ifndef DATABASE_H
  17 #define DATABASE_H
  18 #include<os.h>
  19 #include<Allocator.h>
  20 #include<Debug.h>
  21 #include<Util.h>
  22 #include<Process.h>
  23
  24 class Bucket;
  25 class Transaction;
  26 class Database;
  27
  28 class DllExport DatabaseMetaData
  29 {
  30     public:
  31     int dbID_;
  32     char dbName_[IDENTIFIER_LENGTH];
  33
  34     //TODO:: move this from here to system database
  35     //as only sys db has the limit and user
  36     //database does not have any limit for chunks
  37     int noOfChunks_;
  38
  39     long maxSize_; //maximum size of database
  40     long curSize_; //current size of database
  41
  42     //current page, this is used by the allocator to get new free page
  43     Page *curPage_;
  44
  45     //first page, usually after this database meta data
  46     //getFreePage function uses this to get the free page in this database
  47     Page *firstPage_;
  48
  49
  50     //This mutex is taken if pageInfo is accessed or modified for
  51     //this database
  52     Mutex dbAllocMutex_;
  53
  54     Mutex ckptMutex_;
  55
  56     Mutex dbTransTableMutex_;
  57
  58     Mutex dbProcTableMutex_;
  59
  60     // This mutex is taken for prepare in SqlStatement
  61     Mutex dbPrepareStmtMutex_;
  62
  63     //To generate unique id
  64     UniqueID chunkUniqueID_;
  65
  66     //This is where all hash index nodes are stored for all the
  67     //indexes in this database
  68     Chunk *hashIndexChunk_;
  69
  70     bool canTakeCheckPoint_;
  71
  72     unsigned char reserved_[780];
  73 };
  74
  75
  76 class DatabaseManagerImpl;
  77 class Table;
  78 class ProcInfo;
  79 class ThreadInfo;
  80 class Transaction;
  81
  82 class DllExport Database
  83 {
  84     private:
  85     //Only DatabaseManager creates this object
  86     //initialization is done only in DatabaseManager during
  87     //create, delete, open, close database methods
  88     Database() { metaData_ = NULL; procSlot = -1; fdChkpt = (file_desc)-1; thrInfoOffset=0;}
  89     DatabaseMetaData *metaData_;
  90     file_desc fdChkpt;
  91     int thrInfoOffset;
  92
  93
  94     public:
  95
  96     DbRetVal createSystemDatabaseChunk(AllocType type = FixedSizeAllocator,
  97                                       size_t size = 0, int chunkID=-1);
  98     DbRetVal deleteSystemDatabaseChunk(int id);
  99
 100     inline Chunk*  getSystemDatabaseChunk(int id);
 101     Transaction* getSystemDatabaseTrans(int slot);
 102     inline void setThrInfoOffset() {
 103         thrInfoOffset = os::alignLong(sizeof (DatabaseMetaData)) +
 104                         os::alignLong( MAX_CHUNKS  * sizeof (Chunk)) +
 105                os::alignLong( Conf::config.getMaxProcs()*sizeof(Transaction));
 106     }
 107     inline ThreadInfo* getThreadInfo(int slot){
 108         if (!thrInfoOffset) setThrInfoOffset();
 109         size_t off = thrInfoOffset + slot * sizeof (ThreadInfo);
 110         return (ThreadInfo*)(((char*) metaData_) +  off);
 111     }
 112
 113     //ThreadInfo* getThreadInfo(int pidSlot, int thrSlot);
 114     bool isLastThread();
 115
 116     void createAllCatalogTables();
 117     void createSystemTables();
 118     void createMetaDataTables();
 119
 120     void* allocLockHashBuckets();
 121     Bucket* getLockHashBuckets();
 122
 123     void incrementChunk() { (metaData_->noOfChunks_)++;}
 124     void decrementChunk() { (metaData_->noOfChunks_)--;}
 125
 126     int getUniqueIDForChunk();
 127
 128     const char* getName();
 129     int getDatabaseID();
 130     long getMaxSize();
 131     long getCurrentSize();
 132     Page* getCurrentPage();
 133     int getNoOfChunks();
 134     DatabaseMetaData* getMetaDataPtr() { return metaData_; }
 135     Page* getFirstPage();
 136     Chunk* getHashIndexChunk();
 137     file_desc getChkptfd() { return fdChkpt; }
 138     bool getCanTakeCheckPoint() { return metaData_->canTakeCheckPoint_; }
 139
 140     void setDatabaseID(int id);
 141     void setName(const char *name);
 142     void setCurrentSize(long size);
 143     void setCurrentPage(Page *page);
 144     void setMaxSize(long size);
 145     void setNoOfChunks(int maxChunks);
 146     void setMetaDataPtr(DatabaseMetaData *ptr) {metaData_ = ptr; }
 147     void setFirstPage(Page *ptr);
 148     void setHashIndexChunk(Chunk* chunk);
 149     void setUniqueChunkID(int id);
 150     void setChkptfd(file_desc fd) { fdChkpt = fd; }
 151     void setCanTakeCheckPoint(bool ctcp)
 152     { metaData_->canTakeCheckPoint_ = ctcp; }
 153     // Gets the free page
 154     // Each page is segmented by PAGE_SIZE, so it checks the pageInfo
 155     // of each page to determine if the page is free
 156     Page* getFreePage();
 157     Page* getFreePage(size_t size);
 158
 159     void printStatistics();
 160
 161     int initAllocDatabaseMutex();
 162     DbRetVal getAllocDatabaseMutex(bool procAccount = true);
 163     DbRetVal releaseAllocDatabaseMutex(bool procAccount = true);
 164
 165     int initTransTableMutex();
 166     DbRetVal getTransTableMutex();
 167     DbRetVal releaseTransTableMutex();
 168
 169     int initCheckpointMutex();
 170     DbRetVal getSCheckpointMutex(bool procAccount = true);
 171     DbRetVal getXCheckpointMutex(bool procAccount = true);
 172     DbRetVal releaseCheckpointMutex(bool procAccount = true);
 173
 174     int initProcessTableMutex();
 175     DbRetVal getProcessTableMutex(bool procAccount = true);
 176     DbRetVal releaseProcessTableMutex(bool procAccount = true);
 177
 178     int initPrepareStmtMutex();
 179     DbRetVal getPrepareStmtMutex(bool procAccount = true);
 180     DbRetVal releasePrepareStmtMutex(bool procAccount = true);
 181
 182     DbRetVal recoverMutex(Mutex *mut);
 183
 184     int procSlot;
 185     void setProcSlot(int slot) { procSlot =slot;}
 186     //checks whether the ptr falls in the range of the database file size
 187     bool isValidAddress(void *ptr);
 188
 189     DbRetVal writeDirtyPages(char *chkptFile);
 190     DbRetVal checkPoint();
 191     DbRetVal filterAndRemoveStmtLogs();
 192     DbRetVal recoverUserDB();
 193     DbRetVal recoverSystemDB();
 194     static int getCheckpointID();
 195     static void setCheckpointID(int id);
 196
 197     friend class DatabaseManagerImpl;
 198     friend class Table;
 199     friend class TreeIndex;
 200     friend class HashIndex;
 201     friend class Transaction;
 202
 203 };
 204
 205 #endif