* Merged the tmpsql branch:

- Abstraction for the sql code (sql.c/h).
- New configure script and makefiles.
- Restored txt zeny logging code. (r10814)
- Rewrote mapserver's sql code - itemdb, mobdb, mapreg, logs. (r10814)
- Fixed a precedence issue (&& and ) in char_sql/char.c. (r10833)
- Improved db reading code a bit for consistency. (r11077)
- Added separate atcommand for mail deletion. (r11077)
- Corrected a few messages that said "new" instead of "unread". (r11077)
- Broadcast (*) messages now use "*" as the target's name (not ""). (r11077)
- Moved StringBuf code from utils.c/h to strlib.c/h. (r11084 r11117)
- Some misc login server cleanups (reformatting etc). (r11136)
- Corrected/modified some header entries. (r11141 r11147 11148)
- Adjusted VS project files. (r11147)
- Adjusted the way the sql charserver does item saving. (r11192)
- Corrected usage of reserved keyword 'friend' in mmo.h. (r11192)

git-svn-id: https://rathena.svn.sourceforge.net/svnroot/rathena/trunk@11245 54d463be-8e91-2dee-dedb-b68131a5f0ec

1 files changed, 851 insertions, 0 deletions

diff --git a/src/common/sql.c b/src/common/sql.c
new file mode 100644
index 000000000..cc6e81009
--- /dev/null
+++ b/src/common/sql.c
@@ -0,0 +1,851 @@
+// Copyright (c) Athena Dev Teams - Licensed under GNU GPL
+// For more information, see LICENCE in the main folder
+
+#include "../common/cbasetypes.h"
+#include "../common/malloc.h"
+#include "../common/showmsg.h"
+#include "../common/strlib.h"
+#include "sql.h"
+
+#ifdef WIN32
+#include <winsock2.h>
+#endif
+#include <mysql.h>
+#include <string.h>// strlen/strnlen/memcpy/memset
+#include <stdlib.h>// strtoul
+
+
+
+/// Sql handle
+struct Sql
+{
+	StringBuf buf;
+	MYSQL handle;
+	MYSQL_RES* result;
+	MYSQL_ROW row;
+	unsigned long* lengths;
+};
+
+
+
+// Column length receiver.
+// Takes care of the possible size missmatch between uint32 and unsigned long.
+struct s_column_length
+{
+	uint32* out_length;
+	unsigned long length;
+};
+typedef struct s_column_length s_column_length;
+
+
+
+/// Sql statement
+struct SqlStmt
+{
+	StringBuf buf;
+	MYSQL_STMT* stmt;
+	MYSQL_BIND* params;
+	MYSQL_BIND* columns;
+	s_column_length* column_lengths;
+	size_t max_params;
+	size_t max_columns;
+	bool bind_params;
+	bool bind_columns;
+};
+
+
+
+///////////////////////////////////////////////////////////////////////////////
+// Sql Handle
+///////////////////////////////////////////////////////////////////////////////
+
+
+
+/// Allocates and initializes a new Sql handle.
+Sql* Sql_Malloc(void)
+{
+	Sql* self;
+	CREATE(self, Sql, 1);
+	mysql_init(&self->handle);
+	StringBuf_Init(&self->buf);
+	return self;
+}
+
+
+
+/// Establishes a connection.
+int Sql_Connect(Sql* self, const char* user, const char* passwd, const char* host, uint16 port, const char* db)
+{
+	if( self == NULL )
+		return SQL_ERROR;
+
+	StringBuf_Clear(&self->buf);
+	if( !mysql_real_connect(&self->handle, host, user, passwd, db, (unsigned int)port, NULL/*unix_socket*/, 0/*clientflag*/) )
+	{
+		ShowSQL("%s\n", mysql_error(&self->handle));
+		return SQL_ERROR;
+	}
+	return SQL_SUCCESS;
+}
+
+
+
+/// Retrieves the timeout of the connection.
+int Sql_GetTimeout(Sql* self, uint32* out_timeout)
+{
+	if( self && out_timeout && SQL_SUCCESS == Sql_Query(self, "SHOW VARIABLES LIKE 'wait_timeout'") )
+	{
+		char* data;
+		size_t len;
+		if( SQL_SUCCESS == Sql_NextRow(self) &&
+			SQL_SUCCESS == Sql_GetData(self, 1, &data, &len) )
+		{
+			*out_timeout = (uint32)strtoul(data, NULL, 10);
+			Sql_FreeResult(self);
+			return SQL_SUCCESS;
+		}
+		Sql_FreeResult(self);
+	}
+	return SQL_ERROR;
+}
+
+
+
+/// Retrieves the name of the columns of a table into out_buf, with the separator after each name.
+int Sql_GetColumnNames(Sql* self, const char* table, char* out_buf, size_t buf_len, char sep)
+{
+	char* data;
+	size_t len;
+	size_t off = 0;
+
+	if( self == NULL || SQL_ERROR == Sql_Query(self, "EXPLAIN `%s`", table) )
+		return SQL_ERROR;
+
+	out_buf[off] = '\0';
+	while( SQL_SUCCESS == Sql_NextRow(self) && SQL_SUCCESS == Sql_GetData(self, 0, &data, &len) )
+	{
+		len = strnlen(data, len);
+		if( off + len + 2 > buf_len )
+		{
+			ShowDebug("Sql_GetColumns: output buffer is too small\n");
+			*out_buf = '\0';
+			return SQL_ERROR;
+		}
+		memcpy(out_buf+off, data, len);
+		off += len;
+		out_buf[off++] = sep;
+	}
+	out_buf[off] = '\0';
+	Sql_FreeResult(self);
+	return SQL_SUCCESS;
+}
+
+
+
+/// Changes the encoding of the connection.
+int Sql_SetEncoding(Sql* self, const char* encoding)
+{
+	return Sql_Query(self, "SET NAMES %s", encoding);
+}
+
+
+
+/// Pings the connection.
+int Sql_Ping(Sql* self)
+{
+	if( self && mysql_ping(&self->handle) == 0 )
+		return SQL_SUCCESS;
+	return  SQL_ERROR;
+}
+
+
+
+/// Escapes a string.
+size_t Sql_EscapeString(Sql* self, char *out_to, const char *from)
+{
+	if( self )
+		return (size_t)mysql_real_escape_string(&self->handle, out_to, from, (unsigned long)strlen(from));
+	else
+		return (size_t)mysql_escape_string(out_to, from, (unsigned long)strlen(from));
+}
+
+
+
+/// Escapes a string.
+size_t Sql_EscapeStringLen(Sql* self, char *out_to, const char *from, size_t from_len)
+{
+	if( self )
+		return (size_t)mysql_real_escape_string(&self->handle, out_to, from, (unsigned long)from_len);
+	else
+		return (size_t)mysql_escape_string(out_to, from, (unsigned long)from_len);
+}
+
+
+
+/// Executes a query.
+int Sql_Query(Sql* self, const char* query, ...)
+{
+	int res;
+	va_list args;
+
+	va_start(args, query);
+	res = Sql_QueryV(self, query, args);
+	va_end(args);
+
+	return res;
+}
+
+
+
+/// Executes a query.
+int Sql_QueryV(Sql* self, const char* query, va_list args)
+{
+	if( self == NULL )
+		return SQL_ERROR;
+
+	Sql_FreeResult(self);
+	StringBuf_Clear(&self->buf);
+	StringBuf_Vprintf(&self->buf, query, args);
+	if( mysql_real_query(&self->handle, StringBuf_Value(&self->buf), (unsigned long)StringBuf_Length(&self->buf)) )
+	{
+		ShowSQL("DB error - %s\n", mysql_error(&self->handle));
+		return SQL_ERROR;
+	}
+	self->result = mysql_store_result(&self->handle);
+	if( mysql_errno(&self->handle) != 0 )
+	{
+		ShowSQL("DB error - %s\n", mysql_error(&self->handle));
+		return SQL_ERROR;
+	}
+	return SQL_SUCCESS;
+}
+
+
+
+/// Executes a query.
+int Sql_QueryStr(Sql* self, const char* query)
+{
+	if( self == NULL )
+		return SQL_ERROR;
+
+	Sql_FreeResult(self);
+	StringBuf_Clear(&self->buf);
+	StringBuf_AppendStr(&self->buf, query);
+	if( mysql_real_query(&self->handle, StringBuf_Value(&self->buf), (unsigned long)StringBuf_Length(&self->buf)) )
+	{
+		ShowSQL("DB error - %s\n", mysql_error(&self->handle));
+		return SQL_ERROR;
+	}
+	self->result = mysql_store_result(&self->handle);
+	if( mysql_errno(&self->handle) != 0 )
+	{
+		ShowSQL("DB error - %s\n", mysql_error(&self->handle));
+		return SQL_ERROR;
+	}
+	return SQL_SUCCESS;
+}
+
+
+
+/// Returns the number of the AUTO_INCREMENT column of the last INSERT/UPDATE query.
+uint64 Sql_LastInsertId(Sql* self)
+{
+	if( self )
+		return (uint64)mysql_insert_id(&self->handle);
+	else
+		return 0;
+}
+
+
+
+/// Returns the number of columns in each row of the result.
+uint32 Sql_NumColumns(Sql* self)
+{
+	if( self && self->result )
+		return (uint32)mysql_num_fields(self->result);
+	return 0;
+}
+
+
+
+/// Returns the number of rows in the result.
+uint64 Sql_NumRows(Sql* self)
+{
+	if( self && self->result )
+		return (uint64)mysql_num_rows(self->result);
+	return 0;
+}
+
+
+
+/// Fetches the next row.
+int Sql_NextRow(Sql* self)
+{
+	if( self && self->result )
+	{
+		self->row = mysql_fetch_row(self->result);
+		if( self->row )
+		{
+			self->lengths = mysql_fetch_lengths(self->result);
+			return SQL_SUCCESS;
+		}
+		self->lengths = NULL;
+		if( mysql_errno(&self->handle) == 0 )
+			return SQL_NO_DATA;
+	}
+	return SQL_ERROR;
+}
+
+
+
+/// Gets the data of a column.
+int Sql_GetData(Sql* self, size_t col, char** out_buf, size_t* out_len)
+{
+	if( self && self->row )
+	{
+		if( col < Sql_NumColumns(self) )
+		{
+			if( out_buf ) *out_buf = self->row[col];
+			if( out_len ) *out_len = (size_t)self->lengths[col];
+		}
+		else
+		{// out of range - ignore
+			if( out_buf ) *out_buf = NULL;
+			if( out_len ) *out_len = 0;
+		}
+		return SQL_SUCCESS;
+	}
+	return SQL_ERROR;
+}
+
+
+
+/// Frees the result of the query.
+void Sql_FreeResult(Sql* self)
+{
+	if( self && self->result )
+	{
+		mysql_free_result(self->result);
+		self->result = NULL;
+		self->row = NULL;
+		self->lengths = NULL;
+	}
+}
+
+
+
+/// Shows debug information (last query).
+void Sql_ShowDebug_(Sql* self, const char* debug_file, const unsigned long debug_line)
+{
+	if( self == NULL )
+		ShowDebug("at %s:%lu - self is NULL\n", debug_file, debug_line);
+	else if( StringBuf_Length(&self->buf) > 0 )
+		ShowDebug("at %s:%lu - %s\n", debug_file, debug_line, StringBuf_Value(&self->buf));
+	else
+		ShowDebug("at %s:%lu\n", debug_file, debug_line);
+}
+
+
+
+/// Frees a Sql handle returned by Sql_Malloc.
+void Sql_Free(Sql* self) 
+{
+	if( self )
+	{
+		Sql_FreeResult(self);
+		StringBuf_Destroy(&self->buf);
+		aFree(self);
+	}
+}
+
+
+
+///////////////////////////////////////////////////////////////////////////////
+// Prepared Statements
+///////////////////////////////////////////////////////////////////////////////
+
+
+
+/// Returns the mysql integer type for the target size.
+///
+/// @private
+static enum enum_field_types Sql_P_SizeToMysqlIntType(int sz)
+{
+	switch( sz )
+	{
+	case 1: return MYSQL_TYPE_TINY;
+	case 2: return MYSQL_TYPE_SHORT;
+	case 4: return MYSQL_TYPE_LONG;
+	case 8: return MYSQL_TYPE_LONGLONG;
+	default:
+		ShowDebug("SizeToMysqlIntType: unsupported size (%d)\n", sz);
+		return MYSQL_TYPE_NULL;
+	}
+}
+
+
+
+/// Binds a parameter/result.
+///
+/// @private
+static int Sql_P_BindSqlDataType(MYSQL_BIND* bind, enum SqlDataType buffer_type, void* buffer, size_t buffer_len, unsigned long* out_length, int8* out_is_null)
+{
+	memset(bind, 0, sizeof(MYSQL_BIND));
+	switch( buffer_type )
+	{
+	case SQLDT_NULL: bind->buffer_type = MYSQL_TYPE_NULL;
+		break;
+	// fixed size
+	case SQLDT_UINT8: bind->is_unsigned = 1;
+	case SQLDT_INT8: bind->buffer_type = MYSQL_TYPE_TINY;
+		break;
+	case SQLDT_UINT16: bind->is_unsigned = 1;
+	case SQLDT_INT16: bind->buffer_type = MYSQL_TYPE_SHORT;
+		break;
+	case SQLDT_UINT32: bind->is_unsigned = 1;
+	case SQLDT_INT32: bind->buffer_type = MYSQL_TYPE_LONG;
+		break;
+	case SQLDT_UINT64: bind->is_unsigned = 1;
+	case SQLDT_INT64: bind->buffer_type = MYSQL_TYPE_LONGLONG;
+		break;
+	// platform dependent size
+	case SQLDT_UCHAR: bind->is_unsigned = 1;
+	case SQLDT_CHAR: bind->buffer_type = Sql_P_SizeToMysqlIntType(sizeof(char));
+		break;
+	case SQLDT_USHORT: bind->is_unsigned = 1;
+	case SQLDT_SHORT: bind->buffer_type = Sql_P_SizeToMysqlIntType(sizeof(short));
+		break;
+	case SQLDT_UINT: bind->is_unsigned = 1;
+	case SQLDT_INT: bind->buffer_type = Sql_P_SizeToMysqlIntType(sizeof(int));
+		break;
+	case SQLDT_ULONG: bind->is_unsigned = 1;
+	case SQLDT_LONG: bind->buffer_type = Sql_P_SizeToMysqlIntType(sizeof(long));
+		break;
+	case SQLDT_ULONGLONG: bind->is_unsigned = 1;
+	case SQLDT_LONGLONG: bind->buffer_type = Sql_P_SizeToMysqlIntType(sizeof(long long));
+		break;
+	// floating point
+	case SQLDT_FLOAT: bind->buffer_type = MYSQL_TYPE_FLOAT;
+		break;
+	case SQLDT_DOUBLE: bind->buffer_type = MYSQL_TYPE_DOUBLE;
+		break;
+	// other
+	case SQLDT_STRING:
+	case SQLDT_ENUM: bind->buffer_type = MYSQL_TYPE_STRING;
+		break;
+	case SQLDT_BLOB: bind->buffer_type = MYSQL_TYPE_BLOB;
+		break;
+	default:
+		ShowDebug("Sql_P_BindSqlDataType: unsupported buffer type (%d)\n", buffer_type);
+		return SQL_ERROR;
+	}
+	bind->buffer = buffer;
+	bind->buffer_length = (unsigned long)buffer_len;
+	bind->length = out_length;
+	bind->is_null = (my_bool*)out_is_null;
+	return SQL_SUCCESS;
+}
+
+
+
+/// Prints debug information about a field (type and length).
+///
+/// @private
+static void Sql_P_ShowDebugMysqlFieldInfo(const char* prefix, enum enum_field_types type, int is_unsigned, unsigned long length, const char* length_postfix)
+{
+	const char* sign = (is_unsigned ? "UNSIGNED " : "");
+	const char* type_string;
+	switch( type )
+	{
+	default:
+		ShowDebug("%stype=%s%u, length=%d\n", prefix, sign, type, length);
+		return;
+#define SHOW_DEBUG_OF(x) case x: type_string = #x; break
+	SHOW_DEBUG_OF(MYSQL_TYPE_TINY);
+	SHOW_DEBUG_OF(MYSQL_TYPE_SHORT);
+	SHOW_DEBUG_OF(MYSQL_TYPE_LONG);
+	SHOW_DEBUG_OF(MYSQL_TYPE_INT24);
+	SHOW_DEBUG_OF(MYSQL_TYPE_LONGLONG);
+	SHOW_DEBUG_OF(MYSQL_TYPE_DECIMAL);
+	SHOW_DEBUG_OF(MYSQL_TYPE_FLOAT);
+	SHOW_DEBUG_OF(MYSQL_TYPE_DOUBLE);
+	SHOW_DEBUG_OF(MYSQL_TYPE_TIMESTAMP);
+	SHOW_DEBUG_OF(MYSQL_TYPE_DATE);
+	SHOW_DEBUG_OF(MYSQL_TYPE_TIME);
+	SHOW_DEBUG_OF(MYSQL_TYPE_DATETIME);
+	SHOW_DEBUG_OF(MYSQL_TYPE_YEAR);
+	SHOW_DEBUG_OF(MYSQL_TYPE_STRING);
+	SHOW_DEBUG_OF(MYSQL_TYPE_VAR_STRING);
+	SHOW_DEBUG_OF(MYSQL_TYPE_BLOB);
+	SHOW_DEBUG_OF(MYSQL_TYPE_SET);
+	SHOW_DEBUG_OF(MYSQL_TYPE_ENUM);
+	SHOW_DEBUG_OF(MYSQL_TYPE_NULL);
+#undef SHOW_DEBUG_TYPE_OF
+	}
+	ShowDebug("%stype=%s%s, length=%d%s\n", prefix, sign, type_string, length, length_postfix); 
+}
+
+
+
+/// Allocates and initializes a new SqlStmt handle.
+SqlStmt* SqlStmt_Malloc(Sql* sql)
+{
+	SqlStmt* self;
+	MYSQL_STMT* stmt;
+
+	if( sql == NULL )
+		return NULL;
+
+	stmt = mysql_stmt_init(&sql->handle);
+	if( stmt == NULL )
+	{
+		ShowSQL("DB error - %s\n", mysql_error(&sql->handle));
+		return NULL;
+	}
+	CREATE(self, SqlStmt, 1);
+	StringBuf_Init(&self->buf);
+	self->stmt = stmt;
+	self->params = NULL;
+	self->columns = NULL;
+	self->column_lengths = NULL;
+	self->max_params = 0;
+	self->max_columns = 0;
+	self->bind_params = false;
+	self->bind_columns = false;
+
+	return self;
+}
+
+
+
+/// Prepares the statement.
+int SqlStmt_Prepare(SqlStmt* self, const char* query, ...)
+{
+	int res;
+	va_list args;
+
+	va_start(args, query);
+	res = SqlStmt_PrepareV(self, query, args);
+	va_end(args);
+
+	return res;
+}
+
+
+
+/// Prepares the statement.
+int SqlStmt_PrepareV(SqlStmt* self, const char* query, va_list args)
+{
+	if( self == NULL )
+		return SQL_ERROR;
+
+	SqlStmt_FreeResult(self);
+	StringBuf_Clear(&self->buf);
+	StringBuf_Vprintf(&self->buf, query, args);
+	if( mysql_stmt_prepare(self->stmt, StringBuf_Value(&self->buf), (unsigned long)StringBuf_Length(&self->buf)) )
+	{
+		ShowSQL("DB error - %s\n", mysql_stmt_error(self->stmt));
+		return SQL_ERROR;
+	}
+	self->bind_params = false;
+
+	return SQL_SUCCESS;
+}
+
+
+
+/// Prepares the statement.
+int SqlStmt_PrepareStr(SqlStmt* self, const char* query)
+{
+	if( self == NULL )
+		return SQL_ERROR;
+
+	SqlStmt_FreeResult(self);
+	StringBuf_Clear(&self->buf);
+	StringBuf_AppendStr(&self->buf, query);
+	if( mysql_stmt_prepare(self->stmt, StringBuf_Value(&self->buf), (unsigned long)StringBuf_Length(&self->buf)) )
+	{
+		ShowSQL("DB error - %s\n", mysql_stmt_error(self->stmt));
+		return SQL_ERROR;
+	}
+	self->bind_params = false;
+
+	return SQL_SUCCESS;
+}
+
+
+
+/// Returns the number of parameters in the prepared statement.
+size_t SqlStmt_NumParams(SqlStmt* self)
+{
+	if( self )
+		return (size_t)mysql_stmt_param_count(self->stmt);
+	else
+		return 0;
+}
+
+
+
+/// Binds a parameter to a buffer.
+int SqlStmt_BindParam(SqlStmt* self, size_t idx, enum SqlDataType buffer_type, void* buffer, size_t buffer_len)
+{
+	if( self == NULL )
+		return SQL_ERROR;
+
+	if( !self->bind_params )
+	{// initialize the bindings
+		size_t i;
+		size_t count;
+
+		count = SqlStmt_NumParams(self);
+		if( self->max_params < count )
+		{
+			self->max_params = count;
+			RECREATE(self->params, MYSQL_BIND, count);
+		}
+		memset(self->params, 0, count*sizeof(MYSQL_BIND));
+		for( i = 0; i < count; ++i )
+			self->params[i].buffer_type = MYSQL_TYPE_NULL;
+		self->bind_params = true;
+	}
+	if( idx < self->max_params )
+		return Sql_P_BindSqlDataType(self->params+idx, buffer_type, buffer, buffer_len, NULL, NULL);
+	else
+		return SQL_SUCCESS;// out of range - ignore
+}
+
+
+
+/// Executes the prepared statement.
+int SqlStmt_Execute(SqlStmt* self)
+{
+	if( self == NULL )
+		return SQL_ERROR;
+
+	SqlStmt_FreeResult(self);
+	if( (self->bind_params && mysql_stmt_bind_param(self->stmt, self->params)) ||
+		mysql_stmt_execute(self->stmt) )
+	{
+		ShowSQL("DB error - %s\n", mysql_stmt_error(self->stmt));
+		return SQL_ERROR;
+	}
+	self->bind_columns = false;
+	if( mysql_stmt_store_result(self->stmt) )// store all the data
+	{
+		ShowSQL("DB error - %s\n", mysql_stmt_error(self->stmt));
+		return SQL_ERROR;
+	}
+
+	return SQL_SUCCESS;
+}
+
+
+
+/// Returns the number of the AUTO_INCREMENT column of the last INSERT/UPDATE statement.
+uint64 SqlStmt_LastInsertId(SqlStmt* self)
+{
+	if( self )
+		return (uint64)mysql_stmt_insert_id(self->stmt);
+	else
+		return 0;
+}
+
+
+
+/// Returns the number of columns in each row of the result.
+size_t SqlStmt_NumColumns(SqlStmt* self)
+{
+	if( self )
+		return (size_t)mysql_stmt_field_count(self->stmt);
+	else
+		return 0;
+}
+
+
+
+/// Binds the result of a column to a buffer.
+int SqlStmt_BindColumn(SqlStmt* self, size_t idx, enum SqlDataType buffer_type, void* buffer, size_t buffer_len, uint32* out_length, int8* out_is_null)
+{
+	if( self == NULL )
+		return SQL_ERROR;
+
+	if( buffer_type == SQLDT_STRING || buffer_type == SQLDT_ENUM )
+	{
+		if( buffer_len < 1 )
+		{
+			ShowDebug("SqlStmt_BindColumn: buffer_len(%d) is too small, no room for the nul-terminator\n", buffer_len);
+			return SQL_ERROR;
+		}
+		--buffer_len;// nul-terminator
+	}
+	if( !self->bind_columns )
+	{// initialize the bindings
+		size_t i;
+		size_t cols;
+
+		cols = SqlStmt_NumColumns(self);
+		if( self->max_columns < cols )
+		{
+			self->max_columns = cols;
+			RECREATE(self->columns, MYSQL_BIND, cols);
+			RECREATE(self->column_lengths, s_column_length, cols);
+		}
+		memset(self->columns, 0, cols*sizeof(MYSQL_BIND));
+		memset(self->column_lengths, 0, cols*sizeof(s_column_length));
+		for( i = 0; i < cols; ++i )
+			self->columns[i].buffer_type = MYSQL_TYPE_NULL;
+		self->bind_columns = true;
+	}
+	if( idx < self->max_columns )
+	{
+		self->column_lengths[idx].out_length = out_length;
+		return Sql_P_BindSqlDataType(self->columns+idx, buffer_type, buffer, buffer_len, &self->column_lengths[idx].length, out_is_null);
+	}
+	else
+	{
+		return SQL_SUCCESS;// out of range - ignore
+	}
+}
+
+
+
+/// Returns the number of rows in the result.
+uint64 SqlStmt_NumRows(SqlStmt* self)
+{
+	if( self )
+		return (uint64)mysql_stmt_num_rows(self->stmt);
+	else
+		return 0;
+}
+
+
+
+/// Fetches the next row.
+int SqlStmt_NextRow(SqlStmt* self)
+{
+	int err;
+	size_t i;
+	size_t cols;
+	MYSQL_BIND* column;
+	unsigned long length;
+
+	if( self == NULL )
+		return SQL_ERROR;
+
+	// bind columns
+	if( self->bind_columns && mysql_stmt_bind_result(self->stmt, self->columns) )
+		err = 1;// error binding columns
+	else
+		err = mysql_stmt_fetch(self->stmt);// fetch row
+
+	// check for errors
+	if( err == MYSQL_NO_DATA )
+		return SQL_NO_DATA;
+	if( err == MYSQL_DATA_TRUNCATED )
+	{
+		my_bool truncated;
+
+		if( !self->bind_columns )
+		{
+			ShowSQL("DB error - data truncated (unknown source, columns are not bound)\n");
+			return SQL_ERROR;
+		}
+
+		// find truncated column
+		cols = SqlStmt_NumColumns(self);
+		for( i = 0; i < cols; ++i )
+		{
+			column = &self->columns[i];
+			column->error = &truncated;
+			mysql_stmt_fetch_column(self->stmt, column, (unsigned int)i, 0);
+			column->error = NULL;
+			if( truncated )
+			{// report truncated column
+				MYSQL_RES* meta;
+				MYSQL_FIELD* field;
+
+				meta = mysql_stmt_result_metadata(self->stmt);
+				field = mysql_fetch_field_direct(meta, (unsigned int)i);
+				ShowSQL("DB error - data of field '%s' was truncated.\n", field->name);
+				ShowDebug("column - %lu\n", (unsigned long)i);
+				Sql_P_ShowDebugMysqlFieldInfo("data   - ", field->type, field->flags&UNSIGNED_FLAG, self->column_lengths[i].length, "");
+				if( column->buffer_type == MYSQL_TYPE_STRING )
+					Sql_P_ShowDebugMysqlFieldInfo("buffer - ", column->buffer_type, column->is_unsigned, column->buffer_length, "+1(nul-terminator)");
+				else
+					Sql_P_ShowDebugMysqlFieldInfo("buffer - ", column->buffer_type, column->is_unsigned, column->buffer_length, "");
+				mysql_free_result(meta);
+				return SQL_ERROR;
+			}
+		}
+		ShowSQL("DB error - data truncated (unknown source)\n");
+		return SQL_ERROR;
+	}
+	if( err )
+	{
+		ShowSQL("DB error - %s\n", mysql_stmt_error(self->stmt));
+		return SQL_ERROR;
+	}
+
+	// propagate column lengths and clear unused parts of string/enum/blob buffers
+	cols = SqlStmt_NumColumns(self);
+	for( i = 0; i < cols; ++i )
+	{
+		length = self->column_lengths[i].length;
+		if( self->column_lengths[i].out_length )
+			*self->column_lengths[i].out_length = (uint32)length;
+		column = &self->columns[i];
+		if( column->buffer_type == MYSQL_TYPE_STRING )
+		{// clear unused part of the string/enum buffer (and nul-terminate)
+			memset((char*)column->buffer + length, 0, column->buffer_length - length + 1);
+		}
+		else if( column->buffer_type == MYSQL_TYPE_BLOB && length < column->buffer_length )
+		{// clear unused part of the blob buffer
+			memset((char*)column->buffer + length, 0, column->buffer_length - length);
+		}
+	}
+
+	return SQL_SUCCESS;
+}
+
+
+
+/// Frees the result of the statement execution.
+void SqlStmt_FreeResult(SqlStmt* self)
+{
+	if( self )
+		mysql_stmt_free_result(self->stmt);
+}
+
+
+
+/// Shows debug information (with statement).
+void SqlStmt_ShowDebug_(SqlStmt* self, const char* debug_file, const unsigned long debug_line)
+{
+	if( self == NULL )
+		ShowDebug("at %s:%lu -  self is NULL\n", debug_file, debug_line);
+	if( StringBuf_Length(&self->buf) > 0 )
+		ShowDebug("at %s:%lu - %s\n", debug_file, debug_line, StringBuf_Value(&self->buf));
+	else
+		ShowDebug("at %s:%lu\n", debug_file, debug_line);
+}
+
+
+
+/// Frees a SqlStmt returned by SqlStmt_Malloc.
+void SqlStmt_Free(SqlStmt* self)
+{
+	if( self )
+	{
+		SqlStmt_FreeResult(self);
+		StringBuf_Destroy(&self->buf);
+		mysql_stmt_close(self->stmt);
+		if( self->params )
+			aFree(self->params);
+		if( self->columns )
+		{
+			aFree(self->columns);
+			aFree(self->column_lengths);
+		}
+		aFree(self);
+	}
+}