Fix #409 Leak of global user vars

(cherry picked from commit 33b71aae0a117707ae3e988a373f9782efb1fbc3)

src/searchd.cpp

@@ -477,7 +477,7 @@ enum Uservar_e
struct Uservar_t
{
	Uservar_e			m_eType { USERVAR_INT_SET };
	UservarIntSet_c *	m_pVal = nullptr;
	CSphRefcountedPtr<UservarIntSet_c>	m_pVal;
};

static CSphMutex					g_tUservarsMutex;
@@ -15899,8 +15899,6 @@ static void UservarAdd ( const CSphString & sName, CSphVector<SphAttr_t> & dVal
		// from here, the old value becomes nameless, though
		assert ( pVar->m_eType==USERVAR_INT_SET );
		assert ( pVar->m_pVal );
		pVar->m_pVal->Release();
		pVar->m_pVal = nullptr;
	} else
	{
		// create a shiny new variable
@@ -15911,9 +15909,8 @@ static void UservarAdd ( const CSphString & sName, CSphVector<SphAttr_t> & dVal

	// swap in the new value
	assert ( pVar );
	assert ( !pVar->m_pVal );
	pVar->m_eType = USERVAR_INT_SET;
	pVar->m_pVal = new UservarIntSet_c();
	pVar->m_pVal = new UservarIntSet_c(); // previous will be auto-released here
	pVar->m_pVal->SwapData ( dVal );
}

@@ -18574,7 +18571,7 @@ static void PrereadFunc ( void * )
struct NamedRefVectorPair_t
{
	CSphString			m_sName;
	UservarIntSet_c *	m_pVal;
	CSphRefcountedPtr<UservarIntSet_c>	m_pVal;
};


@@ -18638,7 +18635,6 @@ static void SphinxqlStateThreadFunc ( void * )
				NamedRefVectorPair_t &tPair = dUservars.Add ();
				tPair.m_sName = g_hUservars.IterateGetKey ();
				tPair.m_pVal = g_hUservars.IterateGet ().m_pVal;
				tPair.m_pVal->AddRef ();
			}
		}
		dUservars.Sort ( bind ( &NamedRefVectorPair_t::m_sName ) );
@@ -18667,10 +18663,6 @@ static void SphinxqlStateThreadFunc ( void * )
			tWriter.PutBytes ( sTail, sizeof ( sTail )-1 );
		}

		// release all locked uservars
		ARRAY_FOREACH ( i, dUservars )
			dUservars[i].m_pVal->Release();

		/////////////////////////////////
		// writing done, flip the burger
		/////////////////////////////////

src/sphinxint.h

@@ -1709,7 +1709,6 @@ uint64_t sphGetSettingsFNV ( const CSphIndexSettings & tSettings );
/// value container for the intset uservar type
class UservarIntSet_c : public CSphVector<SphAttr_t>, public ISphRefcountedMT
{
	~UservarIntSet_c() = default;
};

extern UservarIntSet_c * ( *g_pUservarsHook )( const CSphString & sUservar );