sourcemod/extensions/mysql/mysql/MyStatement.cpp
peace-maker 6fcb411fe4 MySQL: Support multiple result sets in prepared queries (#825)
Prepared statements can return multiple result sets since MySQL 5.5. That can happen when calling stored procedures using `CALL x();`.

This change removes the previous caching of result bindings, since the number of fields in a result can differ from result set to result set. This could potentially have a negative impact on prepared statements always only returning one result set, since the result binding buffers are recreated everytime the statement is executed instead of once. That difference should be negligible.

Fixes #823.
2018-06-05 18:33:33 +01:00

361 lines
7.8 KiB
C++

/**
* vim: set ts=4 :
* =============================================================================
* SourceMod MySQL Extension
* Copyright (C) 2004-2008 AlliedModders LLC. All rights reserved.
* =============================================================================
*
* This program is free software; you can redistribute it and/or modify it under
* the terms of the GNU General Public License, version 3.0, as published by the
* Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*
* As a special exception, AlliedModders LLC gives you permission to link the
* code of this program (as well as its derivative works) to "Half-Life 2," the
* "Source Engine," the "SourcePawn JIT," and any Game MODs that run on software
* by the Valve Corporation. You must obey the GNU General Public License in
* all respects for all other code used. Additionally, AlliedModders LLC grants
* this exception to all derivative works. AlliedModders LLC defines further
* exceptions, found in LICENSE.txt (as of this writing, version JULY-31-2007),
* or <http://www.sourcemod.net/license.php>.
*
* Version: $Id$
*/
#include "MyStatement.h"
#include "MyBoundResults.h"
MyStatement::MyStatement(MyDatabase *db, MYSQL_STMT *stmt)
: m_mysql(db->m_mysql), m_pParent(db), m_stmt(stmt), m_pRes(NULL), m_rs(NULL), m_Results(false)
{
m_Params = (unsigned int)mysql_stmt_param_count(m_stmt);
if (m_Params)
{
m_pushinfo = (ParamBind *)malloc(sizeof(ParamBind) * m_Params);
memset(m_pushinfo, 0, sizeof(ParamBind) * m_Params);
m_bind = (MYSQL_BIND *)malloc(sizeof(MYSQL_BIND) * m_Params);
memset(m_bind, 0, sizeof(MYSQL_BIND) * m_Params);
} else {
m_pushinfo = NULL;
m_bind = NULL;
}
m_Results = false;
}
MyStatement::~MyStatement()
{
while (FetchMoreResults())
{
/* Spin until all are gone */
}
/* Free result set structures */
ClearResults();
/* Free old blobs */
for (unsigned int i=0; i<m_Params; i++)
{
free(m_pushinfo[i].blob);
}
/* Free our allocated arrays */
free(m_pushinfo);
free(m_bind);
/* Close our mysql handles */
mysql_stmt_close(m_stmt);
}
void MyStatement::Destroy()
{
delete this;
}
void MyStatement::ClearResults()
{
if (m_rs)
{
delete m_rs;
m_rs = NULL;
}
if (m_pRes)
{
mysql_free_result(m_pRes);
m_pRes = NULL;
}
m_Results = false;
}
bool MyStatement::FetchMoreResults()
{
if (m_pRes == NULL)
{
return false;
}
else if (!mysql_more_results(m_pParent->m_mysql)) {
return false;
}
ClearResults();
if (mysql_stmt_next_result(m_stmt) != 0)
{
return false;
}
/* the column count is > 0 if there is a result set
* 0 if the result is only the final status packet in CALL queries.
*/
unsigned int num_fields = mysql_stmt_field_count(m_stmt);
if (num_fields == 0)
{
return false;
}
/* Skip away if we don't have data */
m_pRes = mysql_stmt_result_metadata(m_stmt);
if (!m_pRes)
{
return false;
}
/* If we don't have a result manager, create one. */
if (!m_rs)
{
m_rs = new MyBoundResults(m_stmt, m_pRes, num_fields);
}
/* Tell the result set to update its bind info,
* and initialize itself if necessary.
*/
if (!(m_Results = m_rs->Initialize()))
{
return false;
}
/* Try precaching the results. */
m_Results = (mysql_stmt_store_result(m_stmt) == 0);
/* Update now that the data is known. */
m_rs->Update();
/* Return indicator */
return m_Results;
}
void *MyStatement::CopyBlob(unsigned int param, const void *blobptr, size_t length)
{
void *copy_ptr = NULL;
if (m_pushinfo[param].blob != NULL)
{
if (m_pushinfo[param].length < length)
{
free(m_pushinfo[param].blob);
} else {
copy_ptr = m_pushinfo[param].blob;
}
}
if (copy_ptr == NULL)
{
copy_ptr = malloc(length);
m_pushinfo[param].blob = copy_ptr;
m_pushinfo[param].length = length;
}
memcpy(copy_ptr, blobptr, length);
return copy_ptr;
}
bool MyStatement::BindParamInt(unsigned int param, int num, bool signd)
{
if (param >= m_Params)
{
return false;
}
m_pushinfo[param].data.ival = num;
m_bind[param].buffer_type = MYSQL_TYPE_LONG;
m_bind[param].buffer = &(m_pushinfo[param].data.ival);
m_bind[param].is_unsigned = signd ? 0 : 1;
m_bind[param].length = NULL;
return true;
}
bool MyStatement::BindParamFloat(unsigned int param, float f)
{
if (param >= m_Params)
{
return false;
}
m_pushinfo[param].data.fval = f;
m_bind[param].buffer_type = MYSQL_TYPE_FLOAT;
m_bind[param].buffer = &(m_pushinfo[param].data.fval);
m_bind[param].length = NULL;
return true;
}
bool MyStatement::BindParamString(unsigned int param, const char *text, bool copy)
{
if (param >= m_Params)
{
return false;
}
const void *final_ptr;
size_t len;
if (copy)
{
len = strlen(text);
final_ptr = CopyBlob(param, text, len+1);
} else {
len = strlen(text);
final_ptr = text;
}
m_bind[param].buffer_type = MYSQL_TYPE_STRING;
m_bind[param].buffer = (void *)final_ptr;
m_bind[param].buffer_length = (unsigned long)len;
m_bind[param].length = &(m_bind[param].buffer_length);
return true;
}
bool MyStatement::BindParamBlob(unsigned int param, const void *data, size_t length, bool copy)
{
if (param >= m_Params)
{
return false;
}
const void *final_ptr;
if (copy)
{
final_ptr = CopyBlob(param, data, length);
} else {
final_ptr = data;
}
m_bind[param].buffer_type = MYSQL_TYPE_BLOB;
m_bind[param].buffer = (void *)final_ptr;
m_bind[param].buffer_length = (unsigned long)length;
m_bind[param].length = &(m_bind[param].buffer_length);
return true;
}
bool MyStatement::BindParamNull(unsigned int param)
{
if (param >= m_Params)
{
return false;
}
m_bind[param].buffer_type = MYSQL_TYPE_NULL;
return true;
}
bool MyStatement::Execute()
{
/* Clear any past result first! */
while (FetchMoreResults())
{
/* Spin until all are gone */
}
/* Free result set structures */
ClearResults();
/* Bind the parameters */
if (m_Params)
{
if (mysql_stmt_bind_param(m_stmt, m_bind) != 0)
{
return false;
}
}
if (mysql_stmt_execute(m_stmt) != 0)
{
return false;
}
/* the column count is > 0 if there is a result set
* 0 if the result is only the final status packet in CALL queries.
*/
unsigned int num_fields = mysql_stmt_field_count(m_stmt);
if (num_fields == 0)
{
return true;
}
/* Skip away if we don't have data */
m_pRes = mysql_stmt_result_metadata(m_stmt);
if (!m_pRes)
{
return true;
}
/* Create our result manager. */
m_rs = new MyBoundResults(m_stmt, m_pRes, num_fields);
/* Tell the result set to update its bind info,
* and initialize itself if necessary.
*/
if (!(m_Results = m_rs->Initialize()))
{
return false;
}
/* Try precaching the results. */
m_Results = (mysql_stmt_store_result(m_stmt) == 0);
/* Update now that the data is known. */
m_rs->Update();
/* Return indicator */
return m_Results;
}
const char *MyStatement::GetError(int *errCode/* =NULL */)
{
if (errCode)
{
*errCode = mysql_stmt_errno(m_stmt);
}
return mysql_stmt_error(m_stmt);
}
unsigned int MyStatement::GetAffectedRows()
{
return (unsigned int)mysql_stmt_affected_rows(m_stmt);
}
unsigned int MyStatement::GetInsertID()
{
return (unsigned int)mysql_stmt_insert_id(m_stmt);
}
IResultSet *MyStatement::GetResultSet()
{
return (m_Results ? m_rs : NULL);
}