windows-nt/Source/XPSP1/NT/admin/wmi/wbem/common/utillib/chstrarr.cpp
2020-09-26 16:20:57 +08:00

372 lines
9.8 KiB
C++

//***************************************************************************
//
// Copyright (c) 1997-2001 Microsoft Corporation, All Rights Reserved
//
// ChStrArr.CPP
//
// Purpose: utility library version of MFC CStringArray
//
//***************************************************************************
/////////////////////////////////////////////////////////////////////////////
// NOTE: we allocate an array of 'm_nMaxSize' elements, but only
// the current size 'm_nSize' contains properly constructed
// objects.
/////////////////////////////////////////////////////////////////////////////
#include "precomp.h"
#pragma warning( disable : 4290 )
#include <chstring.h>
#include <chstrarr.h>
#include <AssertBreak.h>
extern LPCWSTR afxPchNil;
extern const CHString& afxGetEmptyCHString();
#define afxEmptyCHString afxGetEmptyCHString()
/////////////////////////////////////////////////////////////////////////////
// Special implementations for CHStrings
// it is faster to bit-wise copy a CHString than to call an official
// constructor - since an empty CHString can be bit-wise copied
/////////////////////////////////////////////////////////////////////////////
static inline void ConstructElement(CHString* pNewData)
{
memcpy(pNewData, &afxEmptyCHString, sizeof(CHString));
}
/////////////////////////////////////////////////////////////////////////////
static inline void DestructElement(CHString* pOldData)
{
pOldData->~CHString();
}
/////////////////////////////////////////////////////////////////////////////
static inline void CopyElement(CHString* pSrc, CHString* pDest)
{
*pSrc = *pDest;
}
/////////////////////////////////////////////////////////////////////////////
static void ConstructElements(CHString* pNewData, int nCount)
{
ASSERT_BREAK(nCount >= 0);
while (nCount--)
{
ConstructElement(pNewData);
pNewData++;
}
}
/////////////////////////////////////////////////////////////////////////////
static void DestructElements(CHString* pOldData, int nCount)
{
ASSERT_BREAK(nCount >= 0);
while (nCount--)
{
DestructElement(pOldData);
pOldData++;
}
}
/////////////////////////////////////////////////////////////////////////////
static void CopyElements(CHString* pDest, CHString* pSrc, int nCount)
{
ASSERT_BREAK(nCount >= 0);
while (nCount--)
{
*pDest = *pSrc;
++pDest;
++pSrc;
}
}
/////////////////////////////////////////////////////////////////////////////
CHStringArray::CHStringArray() : m_pData ( NULL ) ,
m_nSize ( 0 ) ,
m_nMaxSize ( 0 ) ,
m_nGrowBy ( 0 )
{
}
/////////////////////////////////////////////////////////////////////////////
CHStringArray::~CHStringArray()
{
DestructElements(m_pData, m_nSize);
delete[] (BYTE*)m_pData;
}
/////////////////////////////////////////////////////////////////////////////
void CHStringArray::SetSize(int nNewSize, int nGrowBy)
{
ASSERT_BREAK(nNewSize >= 0);
if (nGrowBy != -1)
{
m_nGrowBy = nGrowBy; // set new size
}
if (nNewSize == 0)
{
// shrink to nothing
DestructElements(m_pData, m_nSize);
delete[] (BYTE*)m_pData;
m_pData = NULL;
m_nSize = m_nMaxSize = 0;
}
else if (m_pData == NULL)
{
#ifdef SIZE_T_MAX
ASSERT_BREAK(nNewSize <= SIZE_T_MAX/sizeof(CHString)); // no overflow
#endif
// create one with exact size
m_pData = (CHString*) new BYTE[nNewSize * sizeof(CHString)];
if ( m_pData )
{
ConstructElements(m_pData, nNewSize);
m_nSize = m_nMaxSize = nNewSize;
}
else
{
throw CHeap_Exception ( CHeap_Exception :: E_ALLOCATION_ERROR ) ;
}
}
else if (nNewSize <= m_nMaxSize)
{
// it fits
if (nNewSize > m_nSize)
{
// initialize the new elements
ConstructElements(&m_pData[m_nSize], nNewSize-m_nSize);
}
else if (m_nSize > nNewSize) // destroy the old elements
{
DestructElements(&m_pData[nNewSize], m_nSize-nNewSize);
}
m_nSize = nNewSize;
}
else
{
// otherwise, grow array
int nGrowBy = m_nGrowBy;
if (nGrowBy == 0)
{
// heuristically determine growth when nGrowBy == 0
// (this avoids heap fragmentation in many situations)
nGrowBy = min(1024, max(4, m_nSize / 8));
}
int nNewMax;
if (nNewSize < m_nMaxSize + nGrowBy)
{
nNewMax = m_nMaxSize + nGrowBy; // granularity
}
else
{
nNewMax = nNewSize; // no slush
}
ASSERT_BREAK(nNewMax >= m_nMaxSize); // no wrap around
#ifdef SIZE_T_MAX
ASSERT_BREAK(nNewMax <= SIZE_T_MAX/sizeof(CHString)); // no overflow
#endif
CHString* pNewData = (CHString*) new BYTE[nNewMax * sizeof(CHString)];
if ( pNewData )
{
// copy new data from old
memcpy(pNewData, m_pData, m_nSize * sizeof(CHString));
// construct remaining elements
ASSERT_BREAK(nNewSize > m_nSize);
ConstructElements(&pNewData[m_nSize], nNewSize-m_nSize);
// get rid of old stuff (note: no destructors called)
delete[] (BYTE*)m_pData;
m_pData = pNewData;
m_nSize = nNewSize;
m_nMaxSize = nNewMax;
}
else
{
throw CHeap_Exception ( CHeap_Exception :: E_ALLOCATION_ERROR ) ;
}
}
}
/////////////////////////////////////////////////////////////////////////////
int CHStringArray::Append(const CHStringArray& src)
{
ASSERT_BREAK(this != &src); // cannot append to itself
int nOldSize = m_nSize;
SetSize(m_nSize + src.m_nSize);
CopyElements(m_pData + nOldSize, src.m_pData, src.m_nSize);
return nOldSize;
}
/////////////////////////////////////////////////////////////////////////////
void CHStringArray::Copy(const CHStringArray& src)
{
ASSERT_BREAK(this != &src); // cannot append to itself
SetSize(src.m_nSize);
CopyElements(m_pData, src.m_pData, src.m_nSize);
}
/////////////////////////////////////////////////////////////////////////////
void CHStringArray::FreeExtra()
{
if (m_nSize != m_nMaxSize)
{
// shrink to desired size
#ifdef SIZE_T_MAX
ASSERT_BREAK(m_nSize <= SIZE_T_MAX/sizeof(CHString)); // no overflow
#endif
CHString* pNewData = NULL;
if (m_nSize != 0)
{
pNewData = (CHString*) new BYTE[m_nSize * sizeof(CHString)];
if ( pNewData )
{
// copy new data from old
memcpy(pNewData, m_pData, m_nSize * sizeof(CHString));
}
else
{
throw CHeap_Exception ( CHeap_Exception :: E_ALLOCATION_ERROR ) ;
}
}
// get rid of old stuff (note: no destructors called)
delete[] (BYTE*)m_pData;
m_pData = pNewData;
m_nMaxSize = m_nSize;
}
}
/////////////////////////////////////////////////////////////////////////////
void CHStringArray::SetAtGrow(int nIndex, LPCWSTR newElement)
{
ASSERT_BREAK(nIndex >= 0);
if (nIndex >= m_nSize)
{
SetSize(nIndex+1);
}
m_pData[nIndex] = newElement;
}
/////////////////////////////////////////////////////////////////////////////
void CHStringArray::InsertAt(int nIndex, LPCWSTR newElement, int nCount)
{
ASSERT_BREAK(nIndex >= 0); // will expand to meet need
ASSERT_BREAK(nCount > 0); // zero or negative size not allowed
if (nIndex >= m_nSize)
{
// adding after the end of the array
SetSize(nIndex + nCount); // grow so nIndex is valid
}
else
{
// inserting in the middle of the array
int nOldSize = m_nSize;
SetSize(m_nSize + nCount); // grow it to new size
// shift old data up to fill gap
memmove(&m_pData[nIndex+nCount], &m_pData[nIndex],
(nOldSize-nIndex) * sizeof(CHString));
// re-init slots we copied from
ConstructElements(&m_pData[nIndex], nCount);
}
// insert new value in the gap
ASSERT_BREAK(nIndex + nCount <= m_nSize);
while (nCount--)
{
m_pData[nIndex++] = newElement;
}
}
/////////////////////////////////////////////////////////////////////////////
void CHStringArray::RemoveAt(int nIndex, int nCount)
{
ASSERT_BREAK(nIndex >= 0);
ASSERT_BREAK(nCount >= 0);
ASSERT_BREAK(nIndex + nCount <= m_nSize);
// just remove a range
int nMoveCount = m_nSize - (nIndex + nCount);
DestructElements(&m_pData[nIndex], nCount);
if (nMoveCount)
{
memcpy(&m_pData[nIndex], &m_pData[nIndex + nCount],
nMoveCount * sizeof(CHString));
}
m_nSize -= nCount;
}
/////////////////////////////////////////////////////////////////////////////
void CHStringArray::InsertAt(int nStartIndex, CHStringArray* pNewArray)
{
ASSERT_BREAK(pNewArray != NULL);
ASSERT_BREAK(nStartIndex >= 0);
if (pNewArray->GetSize() > 0)
{
InsertAt(nStartIndex, pNewArray->GetAt(0), pNewArray->GetSize());
for (int i = 0; i < pNewArray->GetSize(); i++)
{
SetAt(nStartIndex + i, pNewArray->GetAt(i));
}
}
}
#if (defined DEBUG || defined _DEBUG)
CHString CHStringArray::GetAt(int nIndex) const
{
ASSERT_BREAK(nIndex >= 0 && nIndex < m_nSize);
return m_pData[nIndex];
}
void CHStringArray::SetAt(int nIndex, LPCWSTR newElement)
{
ASSERT_BREAK(nIndex >= 0 && nIndex < m_nSize);
m_pData[nIndex] = newElement;
}
CHString& CHStringArray::ElementAt(int nIndex)
{
ASSERT_BREAK(nIndex >= 0 && nIndex < m_nSize);
return m_pData[nIndex];
}
#endif