Database interface improvement with stl style iterators

common/CMakeLists.txt

@@ -39,6 +39,8 @@ SET(common_sources
 	MiscFunctions.cpp
 	moremath.cpp
 	Mutex.cpp
+	MySQLRequestResult.cpp
+	MySQLRequestRow.cpp
 	opcode_map.cpp
 	opcodemgr.cpp
 	packet_dump.cpp
@@ -149,6 +151,8 @@ SET(common_headers
 	MiscFunctions.h
 	moremath.h
 	Mutex.h
+	MySQLRequestResult.h
+	MySQLRequestRow.h
 	op_codes.h
 	opcode_dispatch.h
 	opcodemgr.h

common/MySQLRequestResult.cpp

@@ -0,0 +1,103 @@
+#include "MySQLRequestResult.h"
+
+
+MySQLRequestResult::MySQLRequestResult()
+	: m_CurrentRow(), m_OneBeyondRow()
+{
+	ZeroOut();
+}
+
+MySQLRequestResult::MySQLRequestResult(MYSQL_RES* result, uint32 rowsAffected, uint32 rowCount, uint32 columnCount, uint32 lastInsertedID, uint32 errorNumber, char *errorBuffer)
+	: m_CurrentRow(result), m_OneBeyondRow()
+{
+	if (errorBuffer != nullptr)
+		m_Success = false;
+	else if (errorBuffer == nullptr && result == nullptr)
+	{
+		m_Success = false;
+		
+#ifdef _EQDEBUG
+		std::cout << "DB Query Error: No Result" << std::endl;
+#endif
+		m_ErrorNumber = UINT_MAX;
+		m_ErrorBuffer = new char[MYSQL_ERRMSG_SIZE];
+
+		strcpy(m_ErrorBuffer, "DBcore::RunQuery: No Result");
+	} 
+	else
+		m_Success = true;
+
+	m_Result = result;
+	m_ErrorBuffer = errorBuffer;
+	m_RowsAffected = rowsAffected;
+	m_RowCount = rowCount;
+	m_ColumnCount = columnCount;
+	m_LastInsertedID = lastInsertedID;
+	m_ErrorNumber = errorNumber;
+}
+
+void MySQLRequestResult::FreeInternals()
+{
+	safe_delete_array(m_ErrorBuffer);
+
+	if (m_Result != nullptr)
+		mysql_free_result(m_Result);
+
+	ZeroOut();
+}
+
+void MySQLRequestResult::ZeroOut()
+{
+	m_Success = false;
+	m_Result = nullptr;
+	m_ErrorBuffer = nullptr;
+	m_RowCount = 0;
+	m_RowsAffected = 0;
+	m_LastInsertedID = 0;
+}
+
+MySQLRequestResult::~MySQLRequestResult()
+{
+	FreeInternals();
+}
+
+MySQLRequestResult::MySQLRequestResult(MySQLRequestResult&& moveItem)
+	: m_CurrentRow(moveItem.m_CurrentRow), m_OneBeyondRow()
+{
+	m_Result = moveItem.m_Result;
+	m_ErrorBuffer = moveItem.m_ErrorBuffer;
+	m_Success = moveItem.m_Success;
+	m_RowCount = moveItem.m_RowCount;
+	m_RowsAffected = moveItem.m_RowsAffected;
+	m_LastInsertedID = moveItem.m_LastInsertedID;
+
+	// Keeps deconstructor from double freeing 
+	// pre move instance.
+	moveItem.ZeroOut();
+}
+
+MySQLRequestResult& MySQLRequestResult::operator=(MySQLRequestResult&& other)
+{
+	// Assigning something to itself?
+	// Silly! (but happens)
+	if (this == &other)
+		return *this;
+
+	FreeInternals();
+
+	m_Success = other.m_Success;
+
+	m_Result = other.m_Result;
+	m_ErrorBuffer = other.m_ErrorBuffer;
+
+	m_RowCount = other.m_RowCount;
+	m_RowsAffected = other.m_RowsAffected;
+	m_LastInsertedID = other.m_LastInsertedID;
+	m_CurrentRow = other.m_CurrentRow;
+	m_OneBeyondRow = other.m_OneBeyondRow;
+	
+	// Keeps deconstructor from double freeing 
+	// pre move instance.
+	other.ZeroOut();
+	return *this;
+}

common/MySQLRequestResult.h

@@ -0,0 +1,54 @@
+#ifndef MYSQL_REQUEST_RESULT_H
+#define MYSQL_REQUEST_RESULT_H
+
+#ifdef _WINDOWS
+	#include <winsock.h>
+	#include <windows.h>
+#endif
+
+#include <mysql.h>
+#include <../common/types.h>
+#include <../common/MySQLRequestRow.h>
+#include <string>
+
+class MySQLRequestResult {
+private:
+	MYSQL_RES* m_Result;
+	char* m_ErrorBuffer;
+	MySQLRequestRow m_CurrentRow;
+	MySQLRequestRow m_OneBeyondRow;
+
+	bool m_Success;
+	uint32 m_RowsAffected;
+	uint32 m_RowCount;
+	uint32 m_ColumnCount;
+	uint32 m_LastInsertedID;
+	uint32 m_ErrorNumber;
+
+
+public:
+
+	MySQLRequestResult(MYSQL_RES* result, uint32 rowsAffected = 0, uint32 rowCount = 0, uint32 columnCount = 0, uint32 lastInsertedID = 0, uint32 errorNumber = 0, char *errorBuffer = nullptr);
+	MySQLRequestResult();	
+	MySQLRequestResult(MySQLRequestResult&& moveItem);
+	~MySQLRequestResult();
+
+	MySQLRequestResult& operator=(MySQLRequestResult&& other);
+
+	bool Success() const { return m_Success;}
+	std::string ErrorMessage() const {return std::string(m_ErrorBuffer);}
+	uint32 ErrorNumber() const {return m_ErrorNumber;}
+	uint32 RowsAffected() const {return m_RowsAffected;}
+	uint32 RowCount() const {return m_RowCount;}
+	uint32 ColumnCount() const {return m_ColumnCount;}
+
+	MySQLRequestRow& begin() { return m_CurrentRow; }
+	MySQLRequestRow& end() { return m_OneBeyondRow;}
+
+private:
+	void FreeInternals();
+	void ZeroOut();
+};
+
+
+#endif

common/MySQLRequestRow.cpp

@@ -0,0 +1,54 @@
+#include "MySQLRequestRow.h"
+
+MySQLRequestRow::MySQLRequestRow(const MySQLRequestRow& row) 
+	: m_Result(row.m_Result), m_MySQLRow(row.m_MySQLRow)
+{
+}
+
+MySQLRequestRow::MySQLRequestRow()
+	: m_Result(nullptr), m_MySQLRow(nullptr)
+{
+}
+
+MySQLRequestRow::MySQLRequestRow(MySQLRequestRow&& moveItem)
+{
+	m_Result = moveItem.m_Result;
+	m_MySQLRow = moveItem.m_MySQLRow;
+
+	moveItem.m_Result = nullptr;
+	moveItem.m_MySQLRow = nullptr;
+}
+
+MySQLRequestRow::MySQLRequestRow(MYSQL_RES *result)
+	: m_Result(result),  m_MySQLRow(mysql_fetch_row(m_Result))
+{
+}
+
+MySQLRequestRow& MySQLRequestRow::operator++()
+{
+	m_MySQLRow = mysql_fetch_row(m_Result);
+	return *this;
+}
+
+MySQLRequestRow MySQLRequestRow::operator++(int) 
+{
+	MySQLRequestRow tmp(*this); 
+	operator++(); 
+	return tmp;
+}
+
+bool MySQLRequestRow::operator==(const MySQLRequestRow& rhs) 
+{
+	return m_MySQLRow == rhs.m_MySQLRow;
+}
+
+bool MySQLRequestRow::operator!=(const MySQLRequestRow& rhs) 
+{
+	return m_MySQLRow != rhs.m_MySQLRow;
+}
+
+char* MySQLRequestRow::operator[](int index)
+{
+
+	return m_MySQLRow[index];
+}

common/MySQLRequestRow.h

@@ -0,0 +1,37 @@
+#ifndef MYSQL_REQUEST_ROW_H
+#define MYSQL_REQUEST_ROW_H
+
+#ifdef _WINDOWS
+	#include <winsock.h>
+	#include <windows.h>
+#endif
+
+#include <mysql.h>
+#include <iterator>
+#include <../common/types.h>
+
+class MySQLRequestRow : public std::iterator<std::input_iterator_tag, MYSQL_ROW>
+{
+
+private:
+	MYSQL_RES* m_Result;
+	MYSQL_ROW m_MySQLRow;
+
+public:
+
+	MySQLRequestRow();
+	MySQLRequestRow(MYSQL_RES *result);
+	MySQLRequestRow(const MySQLRequestRow& row);
+	MySQLRequestRow(MySQLRequestRow&& moveItem);
+	MySQLRequestRow& operator++();
+	MySQLRequestRow operator++(int);
+	bool operator==(const MySQLRequestRow& rhs);
+	bool operator!=(const MySQLRequestRow& rhs);
+
+	char* operator[](int index);
+
+};
+
+
+
+#endif

common/dbcore.cpp

@@ -58,6 +58,83 @@ void DBcore::ping() {
 	MDatabase.unlock();
 }
 
+MySQLRequestResult DBcore::QueryDatabase(const char* query, uint32 querylen, bool retryOnFailureOnce)
+{
+	LockMutex lock(&MDatabase);
+
+	// Reconnect if we are not connected before hand.
+	if (pStatus != Connected)
+		Open();
+
+	// request query. != 0 indicates some kind of error.
+	if (mysql_real_query(&mysql, query, querylen) != 0)
+	{
+		unsigned int errorNumber = mysql_errno(&mysql);
+
+		if (errorNumber == CR_SERVER_GONE_ERROR)
+			pStatus = Error;
+
+		// error appears to be a disconnect error, may need to try again.
+		if (errorNumber == CR_SERVER_LOST || errorNumber == CR_SERVER_GONE_ERROR) 
+		{
+
+			if (retryOnFailureOnce) 
+			{
+				std::cout << "Database Error: Lost connection, attempting to recover...." << std::endl;
+				MySQLRequestResult requestResult = QueryDatabase(query, querylen, false);
+
+				if (requestResult.Success())
+				{
+					std::cout << "Reconnection to database successful." << std::endl;
+					return requestResult;
+				}
+
+			}
+			
+			pStatus = Error;
+			
+			char *errorBuffer = new char[MYSQL_ERRMSG_SIZE];
+
+			snprintf(errorBuffer, MYSQL_ERRMSG_SIZE, "#%i: %s", mysql_errno(&mysql), mysql_error(&mysql));
+			
+			std::cout << "DB Query Error #" << mysql_errno(&mysql) << ": " << mysql_error(&mysql) << std::endl;
+
+			return MySQLRequestResult(nullptr, 0, 0, 0, 0, (uint32)mysql_errno(&mysql), errorBuffer);
+		} 
+		
+		char *errorBuffer = new char[MYSQL_ERRMSG_SIZE];
+		snprintf(errorBuffer, MYSQL_ERRMSG_SIZE, "#%i: %s", mysql_errno(&mysql), mysql_error(&mysql));
+
+#ifdef _EQDEBUG
+		std::cout << "DB Query Error #" << mysql_errno(&mysql) << ": " << mysql_error(&mysql) << std::endl;
+#endif
+		return MySQLRequestResult(nullptr, 0, 0, 0, 0, mysql_errno(&mysql),errorBuffer);
+		
+	}
+
+	// successful query. get results.
+	MYSQL_RES* res = mysql_store_result(&mysql);
+	MySQLRequestResult requestResult(res, (uint32)mysql_affected_rows(&mysql), (uint32)mysql_num_rows(res), (uint32)mysql_field_count(&mysql), (uint32)mysql_insert_id(&mysql));
+
+
+#if DEBUG_MYSQL_QUERIES >= 1
+	if (requestResult.Success()) 
+	{
+		std::cout << "query successful";
+		if (requestResult.Result())
+			std::cout << ", " << (int) mysql_num_rows(requestResult.Result()) << " rows returned";
+		
+		std::cout << ", " << requestResult.RowCount() << " rows affected";
+		std::cout<< std::endl;
+	}
+	else {
+		std::cout << "QUERY: query FAILED" << std::endl;
+	}
+#endif
+
+	return requestResult;
+}
+
 bool DBcore::RunQuery(const char* query, uint32 querylen, char* errbuf, MYSQL_RES** result, uint32* affected_rows, uint32* last_insert_id, uint32* errnum, bool retry) {
 	if (errnum)
 		*errnum = 0;
@@ -111,7 +188,7 @@ bool DBcore::RunQuery(const char* query, uint32 querylen, char* errbuf, MYSQL_RE
 		if (affected_rows)
 			*affected_rows = mysql_affected_rows(&mysql);
 		if (last_insert_id)
-			*last_insert_id = mysql_insert_id(&mysql);
+			*last_insert_id = (uint32)mysql_insert_id(&mysql);
 		if (result) {
 			if (*result) {
 				ret = true;

common/dbcore.h

@@ -4,8 +4,8 @@
 #ifdef _WINDOWS
 	#include <winsock.h>
 	#include <windows.h>
-	//#include <winsock.h>
 #endif
+
 #include <mysql.h>
 #include "../common/types.h"
 #include "../common/Mutex.h"
@@ -13,6 +13,7 @@
 #include "../common/queue.h"
 #include "../common/timer.h"
 #include "../common/Condition.h"
+#include "../common/MySQLRequestResult.h"
 
 class DBcore {
 public:
@@ -22,6 +23,7 @@ public:
 	~DBcore();
 	eStatus	GetStatus() { return pStatus; }
 	bool	RunQuery(const char* query, uint32 querylen, char* errbuf = 0, MYSQL_RES** result = 0, uint32* affected_rows = 0, uint32* last_insert_id = 0, uint32* errnum = 0, bool retry = true);
+	MySQLRequestResult	QueryDatabase(const char* query, uint32 querylen, bool retryOnFailureOnce = true);
 	uint32	DoEscapeString(char* tobuf, const char* frombuf, uint32 fromlen);
 	void	ping();
 	MYSQL*	getMySQL(){ return &mysql; }