greenplumn CBitSetIter 代码
文件路径：/src/backend/gporca/libgpos/src/common/CBitSetIter.cpp
/---------------------------------------------------------------------------
/ Greenplum Database
/ Copyright (C) 2009 Greenplum, Inc.
/
/ @filename:
/ CBitSetIter.cpp
/
/ @doc:
/ Implementation of bitset iterator
/---------------------------------------------------------------------------
#include "gpos/common/CBitSetIter.h"
#include "gpos/base.h"
#include "gpos/common/CAutoRef.h"
using namespace gpos;
/---------------------------------------------------------------------------
/ @function:
/ CBitSetIter::CBitSetIter
/
/ @doc:
/ ctor
/
/---------------------------------------------------------------------------
CBitSetIter::CBitSetIter(const CBitSet &bs)
: m_bs(bs), m_cursor((ULONG) -1), m_bsl(nullptr), m_active(true)
{
}
/---------------------------------------------------------------------------
/ @function:
/ CBitSetIter::Advance
/
/ @doc:
/ Move to next bit
/
/---------------------------------------------------------------------------
BOOL
CBitSetIter::Advance()
{
GPOS_ASSERT(m_active && "called advance on exhausted iterator");
if (nullptr == m_bsl)
{
m_bsl = m_bs.m_bsllist.First();
}
while (nullptr != m_bsl)
{
if (m_cursor + 1 <= m_bs.m_vector_size &&
m_bsl->GetVec()->GetNextSetBit(m_cursor + 1, m_cursor))
{
break;
}
m_bsl = m_bs.m_bsllist.Next(m_bsl);
m_cursor = (ULONG) -1;
}
m_active = (nullptr != m_bsl);
return m_active;
}
/---------------------------------------------------------------------------
/ @function:
/ CBitSetIter::UlBit
/
/ @doc:
/ Return current position of cursor
/
/---------------------------------------------------------------------------
ULONG
CBitSetIter::Bit() const
{
GPOS_ASSERT(m_active && nullptr != m_bsl && "iterator uninitialized");
GPOS_ASSERT(m_bsl->GetVec()->Get(m_cursor));
return m_bsl->GetOffset() + m_cursor;
}
/ EOF