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#ifndef VERS_UTILS_INCLUDED
#define VERS_UTILS_INCLUDED
#include "table.h"
#include "sql_class.h"
#include "vers_string.h"
class MDL_auto_lock
{
THD *thd;
TABLE_LIST &table;
bool error;
public:
MDL_auto_lock(THD *_thd, TABLE_LIST &_table) :
thd(_thd), table(_table)
{
DBUG_ASSERT(thd);
MDL_request protection_request;
if (thd->global_read_lock.can_acquire_protection())
{
error= true;
return;
}
protection_request.init(MDL_key::GLOBAL, "", "", MDL_INTENTION_EXCLUSIVE,
MDL_EXPLICIT);
error= thd->mdl_context.acquire_lock(&protection_request, thd->variables.lock_wait_timeout);
if (error)
return;
table.mdl_request.init(MDL_key::TABLE, table.db.str, table.table_name.str, MDL_EXCLUSIVE, MDL_EXPLICIT);
error= thd->mdl_context.acquire_lock(&table.mdl_request, thd->variables.lock_wait_timeout);
thd->mdl_context.release_lock(protection_request.ticket);
}
~MDL_auto_lock()
{
if (!error)
{
DBUG_ASSERT(table.mdl_request.ticket);
thd->mdl_context.release_lock(table.mdl_request.ticket);
table.mdl_request.ticket= NULL;
}
}
bool acquire_error() const { return error; }
};
#endif // VERS_UTILS_INCLUDED
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