Skip to content
  • Categories
  • Recent
  • Tags
  • Popular
  • Users
  • Groups
  • Search
  • Get Qt Extensions
  • Unsolved
Collapse
Brand Logo
  1. Home
  2. Special Interest Groups
  3. C++ Gurus
  4. Deallocate memory to singleton class which access database ?
Forum Updated to NodeBB v4.3 + New Features

Deallocate memory to singleton class which access database ?

Scheduled Pinned Locked Moved Solved C++ Gurus
35 Posts 5 Posters 7.0k Views
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • jsulmJ jsulm

    @Qt-embedded-developer said in Deallocate memory to singleton class which access database ?:

    I want to free the memory allocated by this class how to do it ?

    As usual with heap allocated memory using delete:

    delete iSqlInstanceDB;
    Q Offline
    Q Offline
    Qt embedded developer
    wrote on last edited by Qt embedded developer
    #3

    @jsulm I want to know how to deallocate memory if my class implemented like below :

    /*
 * SqliteManagerBGSync.h
 *
 *  Created on: 16-Jul-2018
 *      Author: ankita.singh
 */

#ifndef TRANSIT_SRC_SQLITEMANAGERBGSYNC_H_
#define TRANSIT_SRC_SQLITEMANAGERBGSYNC_H_

#include <boomer.h>
#include <sqlite/sqlite3.h>
#include <vector>
#include <string>
#include <pthread.h>
#include "Header/AFCSTicket.h"

namespace app {
namespace dbmanager {

class SqliteManagerBGSync {
public:

public :
	static std::map<int,SqliteManagerBGSync *> sqliteManagerMap;
	static	SqliteManagerBGSync* GetDBInstance();
	sqlite3* handle;
	sqlite3_stmt *statement;
	static sqlite3* getDataBaseHandle();

	static SqliteManagerBGSync* GetDBInstanceForBackSync();
	int prepareStatement(const char *query);
	int openDatabase();
	void closeDatabase();
	boomer::transaction::TransactionResult connectToDataBase(std::string fileName, sqlite3* &handle);
	boomer::transaction::TransactionResult disconnectDataBase(sqlite3* &handle);
	void closeDatabaseForDBBackup();

private:
	std::map<int,sqlite3 *> sqliteHandleMap;
	SqliteManagerBGSync();
	cleanup();

};

} /* namespace dbmanager */
} /* namespace app */

#endif /* TRANSIT_SRC_SQLITEMANAGERBGSYNC_H_ */


    #include "SqliteManagerBGSync.h"
#include <stdio.h>
#include <string>


using namespace std;

using namespace boomer::error;

const char* DB_PATH = "TICKET.DB";
pthread_mutex_t databaseLock;


namespace app
{
namespace dbmanager
{
std::map<int,SqliteManagerBGSync *> SqliteManagerBGSync::sqliteManagerMap;
SqliteManagerBGSync::SqliteManagerBGSync()
{
	DBGF_TRACE("AFCS:SqliteManagerBGSync::Constructor Called");
	handle = NULL;
}

SqliteManagerBGSync::cleanup()
{
for (const auto& kv : sqliteManagerMap) {
    delete kv.second;
}
sqliteManagerMap.clear();

}

SqliteManagerBGSync* SqliteManagerBGSync::GetDBInstance()
{
	std::map<int,SqliteManagerBGSync*>::iterator it;
	int threadId = pthread_self();
	DBGF_TRACE("AFCS:SqliteManagerBGSync::thread Id :%d",threadId);

	//sqliteManagerMap.empty() Return 0 If sqliteManagerMap is Not Empty
	//Return 1 If sqliteManagerMap is Empty
	DBGF_TRACE("AFCS:SqliteManagerBGSync::GetDBInstance()::sqliteManagerMap.empty()=%d",sqliteManagerMap.empty());

	if(sqliteManagerMap.empty())
	{
		DBGF_TRACE("AFCS:SqliteManagerBGSync::GetDBInstance()::sqliteManagerMap.empty() IF");
		if(pthread_mutex_init(&databaseLock, NULL) != 0)
		{
			DBGF_TRACE("databaseLock mutex init failed");

		}
		else
		{
			DBGF_TRACE("databaseLock mutex init Success");

		}
	}
//	else
//	{
//		DBGF_TRACE("AFCS:SqliteManagerBGSync::GetDBInstance()::sqliteManagerMap.empty() Else");
//		sqliteManagerMap.insert(std::pair<int,SqliteManagerBGSync*>(threadId,new SqliteManagerBGSync()));
//		it = sqliteManagerMap.find(threadId);
//		DBGF_TRACE("AFCS:SqliteManagerBGSync::sqliteManagerMap success return 1");
//		return it->second;
//	}

	it = sqliteManagerMap.find(threadId);
	if(it == sqliteManagerMap.end())
	{
		DBGF_TRACE("AFCS:SqliteManagerBGSync::GetDBInstance()::threadId Find Success");

		sqliteManagerMap.insert(std::pair<int,SqliteManagerBGSync*>(threadId,new SqliteManagerBGSync()));
		DBGF_TRACE("AFCS:sqliteManagerMap insert called");

		it = sqliteManagerMap.find(threadId);
	}
	DBGF_TRACE("AFCS:SqliteManagerBGSync::sqliteManagerMap success return 2");

	DBGF_TRACE("SqliteManagerBGSync::GetDBInstance _heap_max() = %d",_heap_max());
	DBGF_TRACE("SqliteManagerBGSync::GetDBInstance _heap_current() = %d",_heap_current());

	return it->second;
}

int SqliteManagerBGSync::openDatabase()
{
	DBGF_TRACE("SqliteManagerBGSync::openDatabase::Mutex locking");

	if(app::Header::AFCSTicket::GetAFCSTicketInstance()->getDBClosed()!=0)
	{
		DBGF_TRACE("SqliteManagerBGSync::openDatabase():: If 1");

		pthread_mutex_lock(&databaseLock);
	}
	DBGF_TRACE("SqliteManagerBGSync::openDatabase::Mutex Locked");
	int memused = sqlite3_memory_used();
	DBGF_TRACE("AFCS:SqliteManager::closeDatabase()::memused=%d",memused);

	if(handle != NULL){

		DBGF_TRACE("before SqliteManagerBGSync::openDatabase _heap_max() = %d",_heap_max());
		DBGF_TRACE("before SqliteManagerBGSync::openDatabase _heap_current() = %d",_heap_current());

		int val = sqlite3_db_release_memory(handle);

		memused = sqlite3_memory_used();
		DBGF_TRACE("AFCS:SqliteManagerBGSync::closeDatabase()::memused=%d",memused);

		DBGF_TRACE("SqliteManagerBGSync::openDatabase sqlite3_db_cacheflush val = %d",val);

		DBGF_TRACE("AFCS:SqliteManagerBGSync::Handle success");
		DBGF_TRACE("SqliteManagerBGSync::openDatabase() _heap_max() = %d",_heap_max());
		DBGF_TRACE("SqliteManagerBGSync::openDatabase() _heap_current() = %d",_heap_current());
		return SUCCESS;
	}

	int res = sqlite3_open(DB_PATH, &handle);
	DBGF_TRACE("AFCS:SqliteManagerBGSync::sqlite3 open = %d",res);


	DBGF_TRACE("AFCS:SqliteManagerBGSync::openDatabase::mutex lock called");
	if(res != SQLITE_OK)
	{
		DBGF_TRACE("SqliteManagerBGSync::openDatabase::Mutex Unlocking");
		if(app::Header::AFCSTicket::GetAFCSTicketInstance()->getDBClosed()!=0)
		{
			DBGF_TRACE("SqliteManagerBGSync::openDatabase():: If 2");
			pthread_mutex_unlock(&databaseLock);
		}
		DBGF_TRACE("SqliteManagerBGSync::openDatabase::Mutex Unlocked");
		DBGF_TRACE("SqliteManagerBGSync::openDatabase() _heap_max() = %d",_heap_max());
	    DBGF_TRACE("SqliteManagerBGSync::openDatabase() _heap_current() = %d",_heap_current());
		ERROR_RETURN(-1);
	}else{
		DBGF_TRACE("AFCS:SqliteManagerBGSync::openDatabase::Sqlite ok");

		if(sqlite3_exec(handle, "PRAGMA journal_mode = WAL;PRAGMA  cache_size = 100000;", NULL, 0, NULL) == SQLITE_OK)
		{
			DBGF_TRACE(" SQLITE QUERY SUCCESS: PRAGMA journal_mode = WAL;PRAGMA  cache_size = 100000;");
			DBGF_TRACE("SqliteManagerBGSync::openDatabase() _heap_max() = %d",_heap_max());
		    DBGF_TRACE("SqliteManagerBGSync::openDatabase() _heap_current() = %d",_heap_current());
			return SUCCESS;
		}
		else
		{
			DBGF_TRACE(" SQLITE QUERY FAIL : PRAGMA journal_mode = WAL;PRAGMA  cache_size = 100000;");
			DBGF_TRACE("SqliteManagerBGSync::openDatabase() _heap_max() = %d",_heap_max());
		    DBGF_TRACE("SqliteManagerBGSync::openDatabase() _heap_current() = %d",_heap_current());
			ERROR_RETURN(0);
		}
		DBGF_TRACE("SqliteManagerBGSync::openDatabase() _heap_max() = %d",_heap_max());
		DBGF_TRACE("SqliteManagerBGSync::openDatabase() _heap_current() = %d",_heap_current());
		return SUCCESS;
	}

}

int SqliteManagerBGSync::prepareStatement(const char *query)
{
	if(openDatabase() != SUCCESS)
	{
		ERROR_RETURN(-1);
	}

	statement = NULL;
	int res = sqlite3_prepare_v2(handle, query, -1, &statement, 0);

	if(res != SQLITE_OK)
	{
		sqlite3_finalize(statement);
		statement = NULL;
		DBGF_TRACE("Mutex Unlocking");
		pthread_mutex_unlock(&databaseLock);
		DBGF_TRACE("Mutex Unlocked");
		ERROR_RETURN(-1);

	}else{
		return SUCCESS;
	}
}


void SqliteManagerBGSync::closeDatabase()
{
	DBGF_TRACE("AFCS:close database called");
	//SVC_WAIT(1000);

	DBGF_TRACE("SqliteManagerBGSync::closeDatabase() _heap_max() = %d",_heap_max());
	DBGF_TRACE("SqliteManagerBGSync::closeDatabase() _heap_current() = %d",_heap_current());

	if (handle != NULL)
	{
		DBGF_TRACE("AFCS:SqliteManagerBGSync::closeDatabase():IF");
		int intReleaseMemoryInBG = 0,intBeforeReleaseInBG=0,intAfterReleaseInBG=0;

		intBeforeReleaseInBG = sqlite3_memory_used();
		intReleaseMemoryInBG = sqlite3_db_release_memory(handle);
		intAfterReleaseInBG = sqlite3_memory_used();

		DBGF_TRACE("AFCS:SqliteManagerBGSync::closeDatabase()::intReleaseMemoryInBG=%d",intReleaseMemoryInBG);
		DBGF_TRACE("AFCS:SqliteManagerBGSync::closeDatabase()::intBeforeReleaseInBG=%d",intBeforeReleaseInBG);
		DBGF_TRACE("AFCS:SqliteManagerBGSync::closeDatabase()::intAfterReleaseInBG=%d",intAfterReleaseInBG);

		int res = sqlite3_close(handle);
		DBGF_TRACE("AFCS:SqliteManagerBGSync::closeDatabase()::res=%d",res);
		if( res == SQLITE_OK)
		{
			DBGF_TRACE("AFCS:SqliteManagerBGSync::closeDatabase()::Close Database Success: %s", sqlite3_errmsg(handle));
			//SVC_WAIT(1000);
			DBGF_TRACE("SqliteManagerBGSync::closeDatabase()::Mutex Unlocking");
			if(app::Header::AFCSTicket::GetAFCSTicketInstance()->getDBClosed()!=0)
			{
				DBGF_TRACE("SqliteManagerBGSync::closeDatabase():: If 1");
				pthread_mutex_unlock(&databaseLock);
			}
			DBGF_TRACE("SqliteManagerBGSync::closeDatabase()::Mutex Unlocked");
			handle = NULL;
			DBGF_TRACE("SqliteManagerBGSync::closeDatabase():: Set handle To NULL");
			DBGF_TRACE("SqliteManagerBGSync::closeDatabase() _heap_max() = %d",_heap_max());
			DBGF_TRACE("SqliteManagerBGSync::closeDatabase() _heap_current() = %d",_heap_current());
		}
		else
		{
			DBGF_TRACE("AFCS:SqliteManagerBGSync::closeDatabase()::Close Database Fail: %s", sqlite3_errmsg(handle));
			//LOGF_ERROR("AFCS:Close Database Error: %s", sqlite3_errmsg(handle));
			//SVC_WAIT(1000);
			DBGF_TRACE("SqliteManagerBGSync::closeDatabase() _heap_max() = %d",_heap_max());
			DBGF_TRACE("SqliteManagerBGSync::closeDatabase() _heap_current() = %d",_heap_current());
		}
		DBGF_TRACE("AFCS:SqliteManagerBGSync::closeDatabase():Complete IF");
	}
	else
	{
		DBGF_TRACE("AFCS:SqliteManagerBGSync::closeDatabase():Else");
		DBGF_TRACE("SqliteManagerBGSync::closeDatabase() _heap_max() = %d",_heap_max());
		DBGF_TRACE("SqliteManagerBGSync::closeDatabase() _heap_current() = %d",_heap_current());
	}
	cleanup();
}

boomer::transaction::TransactionResult SqliteManagerBGSync::connectToDataBase(std::string dbFilename , sqlite3* &handle)
{
	int res = 0;
	res = sqlite3_open(dbFilename.c_str(), &handle);
	if( res != SQLITE_OK )
	{
		ERROR_RETURN(CONFIG_DB_CONNECT_FAILED);
	}

	return boomer::transaction::trOk;
}

boomer::transaction::TransactionResult SqliteManagerBGSync::disconnectDataBase(sqlite3* &handle)
{
	long errCode = 0;
	//Disconnect to DataBase
	int res = sqlite3_close(handle);
	if(res)
	{
		errCode = CONFIG_DB_DISCONNECT_FAILED;
		return res;
	}
	handle = NULL;
	return boomer::transaction::trOk;
}

}

}
    JonBJ 1 Reply Last reply
    0
    • Q Qt embedded developer

      @jsulm I want to know how to deallocate memory if my class implemented like below :

      /*
 * SqliteManagerBGSync.h
 *
 *  Created on: 16-Jul-2018
 *      Author: ankita.singh
 */

#ifndef TRANSIT_SRC_SQLITEMANAGERBGSYNC_H_
#define TRANSIT_SRC_SQLITEMANAGERBGSYNC_H_

#include <boomer.h>
#include <sqlite/sqlite3.h>
#include <vector>
#include <string>
#include <pthread.h>
#include "Header/AFCSTicket.h"

namespace app {
namespace dbmanager {

class SqliteManagerBGSync {
public:

public :
	static std::map<int,SqliteManagerBGSync *> sqliteManagerMap;
	static	SqliteManagerBGSync* GetDBInstance();
	sqlite3* handle;
	sqlite3_stmt *statement;
	static sqlite3* getDataBaseHandle();

	static SqliteManagerBGSync* GetDBInstanceForBackSync();
	int prepareStatement(const char *query);
	int openDatabase();
	void closeDatabase();
	boomer::transaction::TransactionResult connectToDataBase(std::string fileName, sqlite3* &handle);
	boomer::transaction::TransactionResult disconnectDataBase(sqlite3* &handle);
	void closeDatabaseForDBBackup();

private:
	std::map<int,sqlite3 *> sqliteHandleMap;
	SqliteManagerBGSync();
	cleanup();

};

} /* namespace dbmanager */
} /* namespace app */

#endif /* TRANSIT_SRC_SQLITEMANAGERBGSYNC_H_ */


      #include "SqliteManagerBGSync.h"
#include <stdio.h>
#include <string>


using namespace std;

using namespace boomer::error;

const char* DB_PATH = "TICKET.DB";
pthread_mutex_t databaseLock;


namespace app
{
namespace dbmanager
{
std::map<int,SqliteManagerBGSync *> SqliteManagerBGSync::sqliteManagerMap;
SqliteManagerBGSync::SqliteManagerBGSync()
{
	DBGF_TRACE("AFCS:SqliteManagerBGSync::Constructor Called");
	handle = NULL;
}

SqliteManagerBGSync::cleanup()
{
for (const auto& kv : sqliteManagerMap) {
    delete kv.second;
}
sqliteManagerMap.clear();

}

SqliteManagerBGSync* SqliteManagerBGSync::GetDBInstance()
{
	std::map<int,SqliteManagerBGSync*>::iterator it;
	int threadId = pthread_self();
	DBGF_TRACE("AFCS:SqliteManagerBGSync::thread Id :%d",threadId);

	//sqliteManagerMap.empty() Return 0 If sqliteManagerMap is Not Empty
	//Return 1 If sqliteManagerMap is Empty
	DBGF_TRACE("AFCS:SqliteManagerBGSync::GetDBInstance()::sqliteManagerMap.empty()=%d",sqliteManagerMap.empty());

	if(sqliteManagerMap.empty())
	{
		DBGF_TRACE("AFCS:SqliteManagerBGSync::GetDBInstance()::sqliteManagerMap.empty() IF");
		if(pthread_mutex_init(&databaseLock, NULL) != 0)
		{
			DBGF_TRACE("databaseLock mutex init failed");

		}
		else
		{
			DBGF_TRACE("databaseLock mutex init Success");

		}
	}
//	else
//	{
//		DBGF_TRACE("AFCS:SqliteManagerBGSync::GetDBInstance()::sqliteManagerMap.empty() Else");
//		sqliteManagerMap.insert(std::pair<int,SqliteManagerBGSync*>(threadId,new SqliteManagerBGSync()));
//		it = sqliteManagerMap.find(threadId);
//		DBGF_TRACE("AFCS:SqliteManagerBGSync::sqliteManagerMap success return 1");
//		return it->second;
//	}

	it = sqliteManagerMap.find(threadId);
	if(it == sqliteManagerMap.end())
	{
		DBGF_TRACE("AFCS:SqliteManagerBGSync::GetDBInstance()::threadId Find Success");

		sqliteManagerMap.insert(std::pair<int,SqliteManagerBGSync*>(threadId,new SqliteManagerBGSync()));
		DBGF_TRACE("AFCS:sqliteManagerMap insert called");

		it = sqliteManagerMap.find(threadId);
	}
	DBGF_TRACE("AFCS:SqliteManagerBGSync::sqliteManagerMap success return 2");

	DBGF_TRACE("SqliteManagerBGSync::GetDBInstance _heap_max() = %d",_heap_max());
	DBGF_TRACE("SqliteManagerBGSync::GetDBInstance _heap_current() = %d",_heap_current());

	return it->second;
}

int SqliteManagerBGSync::openDatabase()
{
	DBGF_TRACE("SqliteManagerBGSync::openDatabase::Mutex locking");

	if(app::Header::AFCSTicket::GetAFCSTicketInstance()->getDBClosed()!=0)
	{
		DBGF_TRACE("SqliteManagerBGSync::openDatabase():: If 1");

		pthread_mutex_lock(&databaseLock);
	}
	DBGF_TRACE("SqliteManagerBGSync::openDatabase::Mutex Locked");
	int memused = sqlite3_memory_used();
	DBGF_TRACE("AFCS:SqliteManager::closeDatabase()::memused=%d",memused);

	if(handle != NULL){

		DBGF_TRACE("before SqliteManagerBGSync::openDatabase _heap_max() = %d",_heap_max());
		DBGF_TRACE("before SqliteManagerBGSync::openDatabase _heap_current() = %d",_heap_current());

		int val = sqlite3_db_release_memory(handle);

		memused = sqlite3_memory_used();
		DBGF_TRACE("AFCS:SqliteManagerBGSync::closeDatabase()::memused=%d",memused);

		DBGF_TRACE("SqliteManagerBGSync::openDatabase sqlite3_db_cacheflush val = %d",val);

		DBGF_TRACE("AFCS:SqliteManagerBGSync::Handle success");
		DBGF_TRACE("SqliteManagerBGSync::openDatabase() _heap_max() = %d",_heap_max());
		DBGF_TRACE("SqliteManagerBGSync::openDatabase() _heap_current() = %d",_heap_current());
		return SUCCESS;
	}

	int res = sqlite3_open(DB_PATH, &handle);
	DBGF_TRACE("AFCS:SqliteManagerBGSync::sqlite3 open = %d",res);


	DBGF_TRACE("AFCS:SqliteManagerBGSync::openDatabase::mutex lock called");
	if(res != SQLITE_OK)
	{
		DBGF_TRACE("SqliteManagerBGSync::openDatabase::Mutex Unlocking");
		if(app::Header::AFCSTicket::GetAFCSTicketInstance()->getDBClosed()!=0)
		{
			DBGF_TRACE("SqliteManagerBGSync::openDatabase():: If 2");
			pthread_mutex_unlock(&databaseLock);
		}
		DBGF_TRACE("SqliteManagerBGSync::openDatabase::Mutex Unlocked");
		DBGF_TRACE("SqliteManagerBGSync::openDatabase() _heap_max() = %d",_heap_max());
	    DBGF_TRACE("SqliteManagerBGSync::openDatabase() _heap_current() = %d",_heap_current());
		ERROR_RETURN(-1);
	}else{
		DBGF_TRACE("AFCS:SqliteManagerBGSync::openDatabase::Sqlite ok");

		if(sqlite3_exec(handle, "PRAGMA journal_mode = WAL;PRAGMA  cache_size = 100000;", NULL, 0, NULL) == SQLITE_OK)
		{
			DBGF_TRACE(" SQLITE QUERY SUCCESS: PRAGMA journal_mode = WAL;PRAGMA  cache_size = 100000;");
			DBGF_TRACE("SqliteManagerBGSync::openDatabase() _heap_max() = %d",_heap_max());
		    DBGF_TRACE("SqliteManagerBGSync::openDatabase() _heap_current() = %d",_heap_current());
			return SUCCESS;
		}
		else
		{
			DBGF_TRACE(" SQLITE QUERY FAIL : PRAGMA journal_mode = WAL;PRAGMA  cache_size = 100000;");
			DBGF_TRACE("SqliteManagerBGSync::openDatabase() _heap_max() = %d",_heap_max());
		    DBGF_TRACE("SqliteManagerBGSync::openDatabase() _heap_current() = %d",_heap_current());
			ERROR_RETURN(0);
		}
		DBGF_TRACE("SqliteManagerBGSync::openDatabase() _heap_max() = %d",_heap_max());
		DBGF_TRACE("SqliteManagerBGSync::openDatabase() _heap_current() = %d",_heap_current());
		return SUCCESS;
	}

}

int SqliteManagerBGSync::prepareStatement(const char *query)
{
	if(openDatabase() != SUCCESS)
	{
		ERROR_RETURN(-1);
	}

	statement = NULL;
	int res = sqlite3_prepare_v2(handle, query, -1, &statement, 0);

	if(res != SQLITE_OK)
	{
		sqlite3_finalize(statement);
		statement = NULL;
		DBGF_TRACE("Mutex Unlocking");
		pthread_mutex_unlock(&databaseLock);
		DBGF_TRACE("Mutex Unlocked");
		ERROR_RETURN(-1);

	}else{
		return SUCCESS;
	}
}


void SqliteManagerBGSync::closeDatabase()
{
	DBGF_TRACE("AFCS:close database called");
	//SVC_WAIT(1000);

	DBGF_TRACE("SqliteManagerBGSync::closeDatabase() _heap_max() = %d",_heap_max());
	DBGF_TRACE("SqliteManagerBGSync::closeDatabase() _heap_current() = %d",_heap_current());

	if (handle != NULL)
	{
		DBGF_TRACE("AFCS:SqliteManagerBGSync::closeDatabase():IF");
		int intReleaseMemoryInBG = 0,intBeforeReleaseInBG=0,intAfterReleaseInBG=0;

		intBeforeReleaseInBG = sqlite3_memory_used();
		intReleaseMemoryInBG = sqlite3_db_release_memory(handle);
		intAfterReleaseInBG = sqlite3_memory_used();

		DBGF_TRACE("AFCS:SqliteManagerBGSync::closeDatabase()::intReleaseMemoryInBG=%d",intReleaseMemoryInBG);
		DBGF_TRACE("AFCS:SqliteManagerBGSync::closeDatabase()::intBeforeReleaseInBG=%d",intBeforeReleaseInBG);
		DBGF_TRACE("AFCS:SqliteManagerBGSync::closeDatabase()::intAfterReleaseInBG=%d",intAfterReleaseInBG);

		int res = sqlite3_close(handle);
		DBGF_TRACE("AFCS:SqliteManagerBGSync::closeDatabase()::res=%d",res);
		if( res == SQLITE_OK)
		{
			DBGF_TRACE("AFCS:SqliteManagerBGSync::closeDatabase()::Close Database Success: %s", sqlite3_errmsg(handle));
			//SVC_WAIT(1000);
			DBGF_TRACE("SqliteManagerBGSync::closeDatabase()::Mutex Unlocking");
			if(app::Header::AFCSTicket::GetAFCSTicketInstance()->getDBClosed()!=0)
			{
				DBGF_TRACE("SqliteManagerBGSync::closeDatabase():: If 1");
				pthread_mutex_unlock(&databaseLock);
			}
			DBGF_TRACE("SqliteManagerBGSync::closeDatabase()::Mutex Unlocked");
			handle = NULL;
			DBGF_TRACE("SqliteManagerBGSync::closeDatabase():: Set handle To NULL");
			DBGF_TRACE("SqliteManagerBGSync::closeDatabase() _heap_max() = %d",_heap_max());
			DBGF_TRACE("SqliteManagerBGSync::closeDatabase() _heap_current() = %d",_heap_current());
		}
		else
		{
			DBGF_TRACE("AFCS:SqliteManagerBGSync::closeDatabase()::Close Database Fail: %s", sqlite3_errmsg(handle));
			//LOGF_ERROR("AFCS:Close Database Error: %s", sqlite3_errmsg(handle));
			//SVC_WAIT(1000);
			DBGF_TRACE("SqliteManagerBGSync::closeDatabase() _heap_max() = %d",_heap_max());
			DBGF_TRACE("SqliteManagerBGSync::closeDatabase() _heap_current() = %d",_heap_current());
		}
		DBGF_TRACE("AFCS:SqliteManagerBGSync::closeDatabase():Complete IF");
	}
	else
	{
		DBGF_TRACE("AFCS:SqliteManagerBGSync::closeDatabase():Else");
		DBGF_TRACE("SqliteManagerBGSync::closeDatabase() _heap_max() = %d",_heap_max());
		DBGF_TRACE("SqliteManagerBGSync::closeDatabase() _heap_current() = %d",_heap_current());
	}
	cleanup();
}

boomer::transaction::TransactionResult SqliteManagerBGSync::connectToDataBase(std::string dbFilename , sqlite3* &handle)
{
	int res = 0;
	res = sqlite3_open(dbFilename.c_str(), &handle);
	if( res != SQLITE_OK )
	{
		ERROR_RETURN(CONFIG_DB_CONNECT_FAILED);
	}

	return boomer::transaction::trOk;
}

boomer::transaction::TransactionResult SqliteManagerBGSync::disconnectDataBase(sqlite3* &handle)
{
	long errCode = 0;
	//Disconnect to DataBase
	int res = sqlite3_close(handle);
	if(res)
	{
		errCode = CONFIG_DB_DISCONNECT_FAILED;
		return res;
	}
	handle = NULL;
	return boomer::transaction::trOk;
}

}

}
      JonBJ Offline
      JonBJ Offline
      JonB
      wrote on last edited by JonB
      #4

      @Qt-embedded-developer
      This is hundreds of lines of code. Nobody else wants to read through all your code, it's not reasonable to ask them to do so. Please produce a minimal example if you have a question.

      Q 1 Reply Last reply
      1
      • JonBJ JonB

        @Qt-embedded-developer
        This is hundreds of lines of code. Nobody else wants to read through all your code, it's not reasonable to ask them to do so. Please produce a minimal example if you have a question.

        Q Offline
        Q Offline
        Qt embedded developer
        wrote on last edited by Qt embedded developer
        #5

        @JonB sorry for write whole code. but can you give example to how to deallocate memory for recent mentioned singleton class ?

        jsulmJ 1 Reply Last reply
        0
        • Q Qt embedded developer

          @JonB sorry for write whole code. but can you give example to how to deallocate memory for recent mentioned singleton class ?

          jsulmJ Offline
          jsulmJ Offline
          jsulm
          Lifetime Qt Champion
          wrote on last edited by
          #6

          @Qt-embedded-developer Can you please explain what the problem is?
          I already gave you an example how to deallocate memory...

          https://forum.qt.io/topic/113070/qt-code-of-conduct

          Q 1 Reply Last reply
          2
          • jsulmJ jsulm

            @Qt-embedded-developer Can you please explain what the problem is?
            I already gave you an example how to deallocate memory...

            Q Offline
            Q Offline
            Qt embedded developer
            wrote on last edited by
            #7

            @jsulm yes i understood that. but to deallocate memory for below 2 statement i need example.

            std::map<int,sqlite3 *> sqliteHandleMap;

            static std::map<int,SqliteManagerBGSync *> sqliteManagerMap;

            i have tried to implement deallocate memory for them like below function in that class like below :

            SqliteManagerBGSync::cleanup()
{
for (const auto& kv : sqliteManagerMap) {
    delete kv.second;
}
sqliteManagerMap.clear();

}

            but it gives me many errors like below:

                    ^

            "src\SqliteManagerBGSync.h", line 42: Error: #260-D: explicit type is missing ("int" assumed)
            cleanup();
            ^
            "src\SqliteManagerBGSync.cpp", line 25: Error: #260-D: explicit type is missing ("int" assumed)
            SqliteManagerBGSync::cleanup()
            ^
            "src\SqliteManagerBGSync.cpp", line 27: Error: #260-D: explicit type is missing ("int" assumed)
            for (const auto& kv : sqliteManagerMap) {
            ^
            "src\SqliteManagerBGSync.cpp", line 27: Error: #252: reference variable "kv" requires an initializer
            for (const auto& kv : sqliteManagerMap) {
            ^
            "src\SqliteManagerBGSync.cpp", line 27: Error: #65: expected a ";"
            for (const auto& kv : sqliteManagerMap) {
            ^
            "src\SqliteManagerBGSync.cpp", line 27: Error: #29: expected an expression
            for (const auto& kv : sqliteManagerMap) {
            ^
            "src\SqliteManagerBGSync.cpp", line 27: Error: #65: expected a ";"
            for (const auto& kv : sqliteManagerMap) {
            ^
            "src\SqliteManagerBGSync.cpp", line 28: Error: #153: expression must have class type
            delete kv.second;
            ^
            "src\SqliteManagerBGSync.cpp", line 32: Error: #940-D: missing return statement at end of non-void function "app::dbmanager::SqliteManagerBGSync::cleanup"
            }

            jsulmJ 1 Reply Last reply
            0
            • Q Qt embedded developer

              I have seen that my project code is use singleton class to access database.

              I want to free the memory allocated by this class how to do it ? can any body give example for that ?

              #ifndef SQLMANAGER_H_
#define SQLMANAGER_H_

#include <boomer.h>
#include <sqlite/sqlite3.h>
#include <vector>
#include <string>
#include "Header/AFCSTicket.h"
//#include "Error.h"

using namespace std;

namespace app
{
namespace dbmanager
{

class SqliteManager {

public :
	static	SqliteManager* GetDBInstance();
	sqlite3* handle;
	sqlite3_stmt *statement;
	static sqlite3* getDataBaseHandle();

	int prepareStatement(const char *query);
	int openDatabase();
	void closeDatabase();
	boomer::transaction::TransactionResult connectToDataBase(std::string fileName, sqlite3* &handle);
	boomer::transaction::TransactionResult disconnectDataBase(sqlite3* &handle);
	void closeDatabaseForDBBackup();
private:
	SqliteManager();
	static SqliteManager* iSqlInstanceDB;

};
}

}
#endif


              
#include "SqliteManager.h"
#include <stdio.h>
#include <string>


using namespace std;

using namespace boomer::error;

const char* DB_PATH_MAIN = "CONFIG.DB";

namespace app
{
namespace dbmanager
{
SqliteManager* SqliteManager::iSqlInstanceDB = NULL;
SqliteManager::SqliteManager()
{
	handle = NULL;
}

SqliteManager* SqliteManager::GetDBInstance()
{
	DBGF_TRACE("SqliteManager::GetDBInstance _heap_max() = %d",_heap_max());
	DBGF_TRACE("SqliteManager::GetDBInstance _heap_current() = %d",_heap_current());

	if ( iSqlInstanceDB == NULL ) {
		iSqlInstanceDB = new SqliteManager();
		DBGF_TRACE("SqliteManager::GetDBInstance _heap_max() = %d",_heap_max());
	  DBGF_TRACE("SqliteManager::GetDBInstance _heap_current() = %d",_heap_current());
	}
	else
	{
	DBGF_TRACE("SqliteManager::GetDBInstance _heap_max() = %d",_heap_max());
	DBGF_TRACE("SqliteManager::GetDBInstance _heap_current() = %d",_heap_current());
	}
	return iSqlInstanceDB;
}

int SqliteManager::openDatabase()
{
	int memused = sqlite3_memory_used();
    DBGF_TRACE("AFCS:SqliteManager::closeDatabase()::memused=%d",memused);

	if(handle != NULL)
	{
		DBGF_TRACE("before SqliteManager::openDatabase _heap_max() = %d",_heap_max());
		DBGF_TRACE("before SqliteManager::openDatabase _heap_current() = %d",_heap_current());


		int val = sqlite3_db_release_memory(handle);

	    memused = sqlite3_memory_used();
		DBGF_TRACE("AFCS:SqliteManager::closeDatabase()::memused=%d",memused);

		DBGF_TRACE("SqliteManager::openDatabase sqlite3_db_cacheflush val = %d",val);

		DBGF_TRACE("SqliteManager::openDatabase _heap_max() = %d",_heap_max());
		DBGF_TRACE("SqliteManager::openDatabase _heap_current() = %d",_heap_current());
		return SUCCESS;
	}

	int res = sqlite3_open(DB_PATH_MAIN, &handle);
	if(res != SQLITE_OK)
	{
  	DBGF_TRACE("SqliteManager::openDatabase _heap_max() = %d",_heap_max());
		DBGF_TRACE("SqliteManager::openDatabase _heap_current() = %d",_heap_current());
		ERROR_RETURN(0);
	}
	else
	{
		DBGF_TRACE("openDatabase _heap_max() = %d",_heap_max());
	  DBGF_TRACE("openDatabase _heap_current() = %d",_heap_current());

	    if(sqlite3_exec(handle, "PRAGMA journal_mode = WAL;PRAGMA  cache_size = 100000;", NULL, 0, NULL) == SQLITE_OK)
		{
	    DBGF_TRACE("SQLITE QUERY SUCCESS: PRAGMA journal_mode = WAL;PRAGMA  cache_size = 100000;");
			DBGF_TRACE("openDatabase _heap_max() = %d",_heap_max());
		  DBGF_TRACE("openDatabase _heap_current() = %d",_heap_current());
			return SUCCESS;
		}
		else
		{
			DBGF_TRACE("SQLITE QUERY FAIL: PRAGMA journal_mode = WAL;PRAGMA  cache_size = 100000;");
			DBGF_TRACE("openDatabase _heap_max() = %d",_heap_max());
			DBGF_TRACE("openDatabase _heap_current() = %d",_heap_current());

			ERROR_RETURN(0);
		}
		DBGF_TRACE("openDatabase _heap_max() = %d",_heap_max());
		DBGF_TRACE("openDatabase _heap_current() = %d",_heap_current());
		return SUCCESS;
	}

}

int SqliteManager::prepareStatement(const char *query)
{
	if(openDatabase() != SUCCESS)
	{
		ERROR_RETURN(0);
	}

	statement = NULL;
	int res = sqlite3_prepare_v2(handle, query, -1, &statement, 0);

	if(res != SQLITE_OK)
	{
		sqlite3_finalize(statement);
		statement = NULL;

		ERROR_RETURN(0);

	}else{
		return SUCCESS;
	}
}


void SqliteManager::closeDatabase()
{
	DBGF_TRACE("_heap_max() = %d",_heap_max());
    DBGF_TRACE("_heap_current() = %d",_heap_current());
	//	if (handle != NULL)
	//	{
	//		if(sqlite3_close(handle) == SQLITE_OK)
	//		{
	//			DBGF_TRACE("Close Database Success: %s", sqlite3_errmsg(handle));
	//			handle = NULL;
	//		}
	//		else
	//			LOGF_ERROR("Close Database Error: %s", sqlite3_errmsg(handle));
	//	}
}

boomer::transaction::TransactionResult SqliteManager::connectToDataBase(std::string dbFilename , sqlite3* &handle)
{
	int res = 0;
	res = sqlite3_open(dbFilename.c_str(), &handle);
	if( res != SQLITE_OK )
	{
		ERROR_RETURN(CONFIG_DB_CONNECT_FAILED);
	}

	return boomer::transaction::trOk;
}

boomer::transaction::TransactionResult SqliteManager::disconnectDataBase(sqlite3* &handle)
{
	long errCode = 0;
	//Disconnect to DataBase
	int res = sqlite3_close(handle);
	if(res)
	{
		errCode = CONFIG_DB_DISCONNECT_FAILED;
		return res;
	}
	handle = NULL;
	return boomer::transaction::trOk;
}
void SqliteManager::closeDatabaseForDBBackup()
{
	DBGF_TRACE("AFCS:SqliteManager::closeDatabaseForDBBackup()");
	if (handle != NULL)
	{
		if(sqlite3_close(handle) == SQLITE_OK)
		{
			DBGF_TRACE("closeDatabaseForDBBackup::Close Database Success: %s", sqlite3_errmsg(handle));
			handle = NULL;
		}
		else
		{
			//LOGF_ERROR("closeDatabaseForDBBackup::Close Database Error: %s", sqlite3_errmsg(handle));
		}
	}
}

}

}
              J.HilkJ Offline
              J.HilkJ Offline
              J.Hilk
              Moderators
              wrote on last edited by J.Hilk
              #8

              @Qt-embedded-developer deleting a singleton instance is not a trivial matter, you have to follow proper guidelines, or you program may explode.

              I would suggest reading and following
              https://www.interviewsansar.com/singleton-class-delete-design/

              Be aware of the Qt Code of Conduct, when posting : https://forum.qt.io/topic/113070/qt-code-of-conduct

              Q: What's that?
              A: It's blue light.
              Q: What does it do?
              A: It turns blue.

              1 Reply Last reply
              3
              • Q Qt embedded developer

                @jsulm yes i understood that. but to deallocate memory for below 2 statement i need example.

                std::map<int,sqlite3 *> sqliteHandleMap;

                static std::map<int,SqliteManagerBGSync *> sqliteManagerMap;

                i have tried to implement deallocate memory for them like below function in that class like below :

                SqliteManagerBGSync::cleanup()
{
for (const auto& kv : sqliteManagerMap) {
    delete kv.second;
}
sqliteManagerMap.clear();

}

                but it gives me many errors like below:

                        ^

                "src\SqliteManagerBGSync.h", line 42: Error: #260-D: explicit type is missing ("int" assumed)
                cleanup();
                ^
                "src\SqliteManagerBGSync.cpp", line 25: Error: #260-D: explicit type is missing ("int" assumed)
                SqliteManagerBGSync::cleanup()
                ^
                "src\SqliteManagerBGSync.cpp", line 27: Error: #260-D: explicit type is missing ("int" assumed)
                for (const auto& kv : sqliteManagerMap) {
                ^
                "src\SqliteManagerBGSync.cpp", line 27: Error: #252: reference variable "kv" requires an initializer
                for (const auto& kv : sqliteManagerMap) {
                ^
                "src\SqliteManagerBGSync.cpp", line 27: Error: #65: expected a ";"
                for (const auto& kv : sqliteManagerMap) {
                ^
                "src\SqliteManagerBGSync.cpp", line 27: Error: #29: expected an expression
                for (const auto& kv : sqliteManagerMap) {
                ^
                "src\SqliteManagerBGSync.cpp", line 27: Error: #65: expected a ";"
                for (const auto& kv : sqliteManagerMap) {
                ^
                "src\SqliteManagerBGSync.cpp", line 28: Error: #153: expression must have class type
                delete kv.second;
                ^
                "src\SqliteManagerBGSync.cpp", line 32: Error: #940-D: missing return statement at end of non-void function "app::dbmanager::SqliteManagerBGSync::cleanup"
                }

                jsulmJ Offline
                jsulmJ Offline
                jsulm
                Lifetime Qt Champion
                wrote on last edited by
                #9

                @Qt-embedded-developer said in Deallocate memory to singleton class which access database ?:

                SqliteManagerBGSync::cleanup()

                C++ basics: return type is missing...

                https://forum.qt.io/topic/113070/qt-code-of-conduct

                Q 1 Reply Last reply
                1
                • jsulmJ jsulm

                  @Qt-embedded-developer said in Deallocate memory to singleton class which access database ?:

                  SqliteManagerBGSync::cleanup()

                  C++ basics: return type is missing...

                  Q Offline
                  Q Offline
                  Qt embedded developer
                  wrote on last edited by
                  #10

                  @jsulm hi jsulm i am returning nothing. my return type is void.

                  jsulmJ 1 Reply Last reply
                  0
                  • Q Qt embedded developer

                    @jsulm hi jsulm i am returning nothing. my return type is void.

                    jsulmJ Offline
                    jsulmJ Offline
                    jsulm
                    Lifetime Qt Champion
                    wrote on last edited by
                    #11

                    @Qt-embedded-developer said in Deallocate memory to singleton class which access database ?:

                    my return type is void.

                    Then write void there. Come on this is really basic stuff...

                    https://forum.qt.io/topic/113070/qt-code-of-conduct

                    Q 1 Reply Last reply
                    1
                    • jsulmJ jsulm

                      @Qt-embedded-developer said in Deallocate memory to singleton class which access database ?:

                      my return type is void.

                      Then write void there. Come on this is really basic stuff...

                      Q Offline
                      Q Offline
                      Qt embedded developer
                      wrote on last edited by
                      #12

                      @jsulm Okay thanks. but still i am getting below errors:

                      "src\SqliteManagerBGSync.cpp", line 27: Error: #260-D: explicit type is missing ("int" assumed)
                      for (const auto& kv : sqliteManagerMap) {
                      ^
                      "src\SqliteManagerBGSync.cpp", line 27: Error: #252: reference variable "kv" requires an initializer
                      for (const auto& kv : sqliteManagerMap) {
                      ^
                      "src\SqliteManagerBGSync.cpp", line 27: Error: #65: expected a ";"
                      for (const auto& kv : sqliteManagerMap) {
                      ^
                      "src\SqliteManagerBGSync.cpp", line 27: Error: #29: expected an expression
                      for (const auto& kv : sqliteManagerMap) {
                      ^
                      "src\SqliteManagerBGSync.cpp", line 27: Error: #65: expected a ";"
                      for (const auto& kv : sqliteManagerMap) {
                      ^
                      "src\SqliteManagerBGSync.cpp", line 28: Error: #153: expression must have class type
                      delete kv.second;

                      KroMignonK J.HilkJ 2 Replies Last reply
                      0
                      • Q Qt embedded developer

                        @jsulm Okay thanks. but still i am getting below errors:

                        "src\SqliteManagerBGSync.cpp", line 27: Error: #260-D: explicit type is missing ("int" assumed)
                        for (const auto& kv : sqliteManagerMap) {
                        ^
                        "src\SqliteManagerBGSync.cpp", line 27: Error: #252: reference variable "kv" requires an initializer
                        for (const auto& kv : sqliteManagerMap) {
                        ^
                        "src\SqliteManagerBGSync.cpp", line 27: Error: #65: expected a ";"
                        for (const auto& kv : sqliteManagerMap) {
                        ^
                        "src\SqliteManagerBGSync.cpp", line 27: Error: #29: expected an expression
                        for (const auto& kv : sqliteManagerMap) {
                        ^
                        "src\SqliteManagerBGSync.cpp", line 27: Error: #65: expected a ";"
                        for (const auto& kv : sqliteManagerMap) {
                        ^
                        "src\SqliteManagerBGSync.cpp", line 28: Error: #153: expression must have class type
                        delete kv.second;

                        KroMignonK Offline
                        KroMignonK Offline
                        KroMignon
                        wrote on last edited by KroMignon
                        #13

                        @Qt-embedded-developer said in Deallocate memory to singleton class which access database ?:

                        Okay thanks. but still i am getting below errors:

                        Do your compiler support C++11 and did you enable C++11 support (eg. add CONFIG += c++11 in your PRO file)?

                        It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth. (Sherlock Holmes)

                        Q 1 Reply Last reply
                        2
                        • KroMignonK KroMignon

                          @Qt-embedded-developer said in Deallocate memory to singleton class which access database ?:

                          Okay thanks. but still i am getting below errors:

                          Do your compiler support C++11 and did you enable C++11 support (eg. add CONFIG += c++11 in your PRO file)?

                          Q Offline
                          Q Offline
                          Qt embedded developer
                          wrote on last edited by Qt embedded developer
                          #14

                          @KroMignon Hi i am not using qt . and sorry i can not enable C++ 11 because my compiler not support it. i can access map like std::map .

                          KroMignonK 1 Reply Last reply
                          0
                          • Q Qt embedded developer

                            @jsulm Okay thanks. but still i am getting below errors:

                            "src\SqliteManagerBGSync.cpp", line 27: Error: #260-D: explicit type is missing ("int" assumed)
                            for (const auto& kv : sqliteManagerMap) {
                            ^
                            "src\SqliteManagerBGSync.cpp", line 27: Error: #252: reference variable "kv" requires an initializer
                            for (const auto& kv : sqliteManagerMap) {
                            ^
                            "src\SqliteManagerBGSync.cpp", line 27: Error: #65: expected a ";"
                            for (const auto& kv : sqliteManagerMap) {
                            ^
                            "src\SqliteManagerBGSync.cpp", line 27: Error: #29: expected an expression
                            for (const auto& kv : sqliteManagerMap) {
                            ^
                            "src\SqliteManagerBGSync.cpp", line 27: Error: #65: expected a ";"
                            for (const auto& kv : sqliteManagerMap) {
                            ^
                            "src\SqliteManagerBGSync.cpp", line 28: Error: #153: expression must have class type
                            delete kv.second;

                            J.HilkJ Offline
                            J.HilkJ Offline
                            J.Hilk
                            Moderators
                            wrote on last edited by
                            #15

                            @Qt-embedded-developer

                            SqliteManagerBGSync();
cleanup();

                            both are missing the return type, and also make sure to fix them in the *.cpp file as well!

                            Be aware of the Qt Code of Conduct, when posting : https://forum.qt.io/topic/113070/qt-code-of-conduct

                            Q: What's that?
                            A: It's blue light.
                            Q: What does it do?
                            A: It turns blue.

                            Q 1 Reply Last reply
                            0
                            • J.HilkJ J.Hilk

                              @Qt-embedded-developer

                              SqliteManagerBGSync();
cleanup();

                              both are missing the return type, and also make sure to fix them in the *.cpp file as well!

                              Q Offline
                              Q Offline
                              Qt embedded developer
                              wrote on last edited by
                              #16

                              @J-Hilk i have changed it . i have used void, But still i am getting as below mentioned error:

                              "src\SqliteManagerBGSync.cpp", line 27: Error: #260-D: explicit type is missing ("int" assumed)
                              for (const auto& kv : sqliteManagerMap) {
                              ^
                              "src\SqliteManagerBGSync.cpp", line 27: Error: #252: reference variable "kv" requires an initializer
                              for (const auto& kv : sqliteManagerMap) {
                              ^
                              "src\SqliteManagerBGSync.cpp", line 27: Error: #65: expected a ";"
                              for (const auto& kv : sqliteManagerMap) {
                              ^
                              "src\SqliteManagerBGSync.cpp", line 27: Error: #29: expected an expression
                              for (const auto& kv : sqliteManagerMap) {
                              ^
                              "src\SqliteManagerBGSync.cpp", line 27: Error: #65: expected a ";"
                              for (const auto& kv : sqliteManagerMap) {
                              ^
                              "src\SqliteManagerBGSync.cpp", line 28: Error: #153: expression must have class type
                              delete kv.second;

                              jsulmJ 1 Reply Last reply
                              0
                              • Q Qt embedded developer

                                @J-Hilk i have changed it . i have used void, But still i am getting as below mentioned error:

                                "src\SqliteManagerBGSync.cpp", line 27: Error: #260-D: explicit type is missing ("int" assumed)
                                for (const auto& kv : sqliteManagerMap) {
                                ^
                                "src\SqliteManagerBGSync.cpp", line 27: Error: #252: reference variable "kv" requires an initializer
                                for (const auto& kv : sqliteManagerMap) {
                                ^
                                "src\SqliteManagerBGSync.cpp", line 27: Error: #65: expected a ";"
                                for (const auto& kv : sqliteManagerMap) {
                                ^
                                "src\SqliteManagerBGSync.cpp", line 27: Error: #29: expected an expression
                                for (const auto& kv : sqliteManagerMap) {
                                ^
                                "src\SqliteManagerBGSync.cpp", line 27: Error: #65: expected a ";"
                                for (const auto& kv : sqliteManagerMap) {
                                ^
                                "src\SqliteManagerBGSync.cpp", line 28: Error: #153: expression must have class type
                                delete kv.second;

                                jsulmJ Offline
                                jsulmJ Offline
                                jsulm
                                Lifetime Qt Champion
                                wrote on last edited by
                                #17

                                @Qt-embedded-developer As @KroMignon already asked you: do you have a C++11 capable compiler? And is C++11 activated?

                                https://forum.qt.io/topic/113070/qt-code-of-conduct

                                Q 1 Reply Last reply
                                1
                                • jsulmJ jsulm

                                  @Qt-embedded-developer As @KroMignon already asked you: do you have a C++11 capable compiler? And is C++11 activated?

                                  Q Offline
                                  Q Offline
                                  Qt embedded developer
                                  wrote on last edited by Qt embedded developer
                                  #18

                                  @jsulm no i have not. So what i have to change in below function:

                                  SqliteManagerBGSync::cleanup()
{
for (const auto& kv : sqliteManagerMap) {
    delete kv.second;
}
sqliteManagerMap.clear();

}
                                  jsulmJ 1 Reply Last reply
                                  0
                                  • Q Qt embedded developer

                                    @KroMignon Hi i am not using qt . and sorry i can not enable C++ 11 because my compiler not support it. i can access map like std::map .

                                    KroMignonK Offline
                                    KroMignonK Offline
                                    KroMignon
                                    wrote on last edited by KroMignon
                                    #19

                                    @Qt-embedded-developer said in Deallocate memory to singleton class which access database ?:

                                    Hi i am not using qt . and sorry i can not enable C++ 11. i can access map like std::map .

                                    The problem is not std::map<>() but the way you iterate through the map: for (const auto& kv : sqliteManagerMap) requires at least C++11 support enabled! (cf. https://en.cppreference.com/w/cpp/container/map)

                                    I don't know which kind of C++ compiler you are using, for GCC for example enabling C++11 is done with -std=c++11 or -std=gnu++11

                                    It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth. (Sherlock Holmes)

                                    Q 1 Reply Last reply
                                    3
                                    • Q Qt embedded developer

                                      @jsulm no i have not. So what i have to change in below function:

                                      SqliteManagerBGSync::cleanup()
{
for (const auto& kv : sqliteManagerMap) {
    delete kv.second;
}
sqliteManagerMap.clear();

}
                                      jsulmJ Offline
                                      jsulmJ Offline
                                      jsulm
                                      Lifetime Qt Champion
                                      wrote on last edited by
                                      #20

                                      @Qt-embedded-developer Then you can't use auto, write the type instead of auto

                                      https://forum.qt.io/topic/113070/qt-code-of-conduct

                                      1 Reply Last reply
                                      1
                                      • KroMignonK KroMignon

                                        @Qt-embedded-developer said in Deallocate memory to singleton class which access database ?:

                                        Hi i am not using qt . and sorry i can not enable C++ 11. i can access map like std::map .

                                        The problem is not std::map<>() but the way you iterate through the map: for (const auto& kv : sqliteManagerMap) requires at least C++11 support enabled! (cf. https://en.cppreference.com/w/cpp/container/map)

                                        I don't know which kind of C++ compiler you are using, for GCC for example enabling C++11 is done with -std=c++11 or -std=gnu++11

                                        Q Offline
                                        Q Offline
                                        Qt embedded developer
                                        wrote on last edited by
                                        #21

                                        @KroMignon i can not enable it like that because any change like that not allowed in my device.

                                        J.HilkJ KroMignonK 2 Replies Last reply
                                        0
                                        • Q Qt embedded developer

                                          @KroMignon i can not enable it like that because any change like that not allowed in my device.

                                          J.HilkJ Offline
                                          J.HilkJ Offline
                                          J.Hilk
                                          Moderators
                                          wrote on last edited by
                                          #22

                                          @Qt-embedded-developer than do a normal for(x; x<y; ++x) loop

                                          Be aware of the Qt Code of Conduct, when posting : https://forum.qt.io/topic/113070/qt-code-of-conduct

                                          Q: What's that?
                                          A: It's blue light.
                                          Q: What does it do?
                                          A: It turns blue.

                                          Q 1 Reply Last reply
                                          1

                                          • Login
                                          • Login or register to search.
                                          • First post
                                            Last post
                                          0
                                          • Categories
                                          • Recent
                                          • Tags
                                          • Popular
                                          • Users
                                          • Groups
                                          • Search
                                          • Get Qt Extensions
                                          • Unsolved