Windows2000/private/windows/shell/dskquota/common/carray.h
2020-09-30 17:12:32 +02:00

596 lines
11 KiB
C++

#ifndef _INC_DSKQUOTA_CARRAY_H
#define _INC_DSKQUOTA_CARRAY_H
/* File: carray.h
Description: Template class CArray. Implements a dynamic array class.
Much of the functionality is based on the feature set of MFC's
CArray class.
Revision History:
Date Description Programmer
-------- --------------------------------------------------- ----------
09/16/97 Initial creation. BrianAu
12/13/97 Changed SetAtGrow to return true/false. True means BrianAu
had to grow array.
*/
#ifndef _INC_DSKQUOTA_DEBUG_H
# include "debug.h"
#endif
#ifndef _INC_DSKQUOTA_THDSYNC_H
# include "thdsync.h"
#endif
#ifndef _INC_DSKQUOTA_EXCEPT_H
# include "except.h"
#endif
template <class T>
class CArray
{
public:
CArray<T>(VOID);
explicit CArray<T>(INT cItems);
CArray<T>(const CArray<T>& rhs);
CArray<T>& operator = (const CArray<T>& rhs);
virtual ~CArray<T>(VOID);
VOID SetAt(const T& item, INT i);
bool SetAtGrow(const T& item, INT i);
T GetAt(INT i) const;
VOID Insert(const T& item, INT i = -1);
VOID Append(const T& item, INT i = -1);
INT Find(const T& key);
VOID Delete(INT i);
T operator [] (INT i) const;
T& operator [] (INT i);
VOID Clear(VOID);
BOOL IsEmpty(VOID) const
{ return 0 == m_cItems; }
INT Count(VOID) const
{ return m_cItems; }
INT UpperBound(VOID) const
{ return m_cItems - 1; }
INT Size(VOID) const
{ return m_cAlloc; }
VOID SetGrow(INT cGrow)
{ m_cGrow = cGrow; }
VOID Copy(const CArray<T>& rhs);
VOID Append(const CArray<T>& rhs);
VOID SetSize(INT cEntries, INT iShift = -1);
VOID Lock(VOID)
{ m_cs.Enter(); }
VOID ReleaseLock(VOID)
{ m_cs.Leave(); }
protected:
static INT DEFGROW; // Default growth value.
private:
INT m_cAlloc; // Number of entry allocations.
INT m_cItems; // Number of used entries.
INT m_cGrow;
T *m_rgItems; // Array of entries.
mutable CCriticalSection m_cs; // For multi-threaded access.
template <class U>
const U& MIN(const U& a, const U& b) const
{
return a < b ? a : b;
}
template <class U>
const U& MAX(const U& a, const U& b) const
{
return a > b ? a : b;
}
};
template <class T>
INT CArray<T>::DEFGROW = 8;
template <class T>
CArray<T>::CArray(
void
) : m_cAlloc(0),
m_cItems(0),
m_cGrow(DEFGROW),
m_rgItems(NULL)
{
}
template <class T>
CArray<T>::CArray(
INT cItems
) : m_cAlloc(0),
m_cItems(0),
m_cGrow(DEFGROW),
m_rgItems(NULL)
{
SetSize(cItems);
m_cItems = cItems;
}
template <class T>
CArray<T>::CArray(
const CArray& rhs
) : m_cAlloc(0),
m_cItems(0),
m_cGrow(DEFGROW),
m_rgItems(NULL)
{
*this = rhs;
}
template <class T>
VOID
CArray<T>::Copy(
const CArray<T>& rhs
)
{
AutoLockCs lock1(rhs.m_cs);
AutoLockCs lock2(m_cs);
// Place *this in an empty state in case Grow() throws an exception.
// It should still be a valid CArray object.
delete[] m_rgItems;
m_rgItems = NULL;
m_cAlloc = 0;
m_cItems = 0;
// Size the object to hold the source array.
SetSize(rhs.m_cAlloc);
// Copy the contents.
DBGASSERT((m_cAlloc >= rhs.m_cItems));
for (m_cItems = 0; m_cItems < rhs.m_cItems; m_cItems++)
{
// This assignment could throw an exception so only update
// our item count after each successful copy.
DBGASSERT((m_cItems < m_cAlloc));
m_rgItems[m_cItems] = rhs.m_rgItems[m_cItems];
}
}
template <class T>
VOID
CArray<T>::Append(
const CArray<T>& rhs
)
{
AutoLockCs lock1(rhs.m_cs);
AutoLockCs lock2(m_cs);
// Size the object to hold both arrays.
SetSize(m_cAlloc + rhs.m_cItems);
// Append the contents.
DBGASSERT((m_cAlloc >= (m_cItems + rhs.m_cItems)));
for (int i = 0; i < rhs.m_cItems; i++)
{
DBGASSERT((m_cItems < m_cAlloc));
m_rgItems[m_cItems++] = rhs.m_rgItems[i];
}
}
template <class T>
CArray<T>&
CArray<T>::operator = (
const CArray<T>& rhs
)
{
if (this != &rhs)
{
Copy(rhs);
}
return *this;
}
template <class T>
CArray<T>::~CArray(
VOID
)
{
Clear();
}
template <class T>
T CArray<T>::operator [] (
INT i
) const
{
return GetAt(i);
}
template <class T>
T& CArray<T>::operator [] (
INT i
)
{
AutoLockCs lock(m_cs);
if (i < 0 || i >= m_cItems)
throw CMemoryException(CMemoryException::index);
return *(m_rgItems + i);
}
template <class T>
VOID
CArray<T>::Clear(
VOID
)
{
AutoLockCs lock(m_cs);
delete[] m_rgItems;
m_rgItems = NULL;
m_cAlloc = 0;
m_cItems = 0;
}
template <class T>
VOID
CArray<T>::Insert(
const T& item,
INT i
)
{
AutoLockCs lock(m_cs);
if (-1 == i)
{
// Insert at head of array.
i = 0;
}
// Can only insert an item before an existing item.
// i cannot be negative.
// If array is empty, i can only be 0.
// If array is not empty, i must be index of a valid item.
if ((0 == m_cItems && 0 != i) ||
(0 != m_cItems && (i < 0 || i >= m_cItems)))
{
throw CMemoryException(CMemoryException::index);
}
DBGASSERT((m_cItems <= m_cAlloc));
if (m_cItems >= m_cAlloc)
{
// Grow the array if necessary.
// This will also shift the elements, beginning with element 'i',
// one element to the right.
SetSize(m_cAlloc + m_cGrow, i);
}
else
{
// Growth not necessary.
// Shift the contents of the array following the insertion point
// one element to the right.
for (int j = m_cItems; j > i; j--)
{
m_rgItems[j] = m_rgItems[j-1];
}
}
// We've now inserted an item.
m_cItems++;
// Set the value at the inserted location.
// This assignment could throw an exception.
SetAt(item, i);
}
template <class T>
VOID
CArray<T>::Append(
const T& item,
INT i
)
{
AutoLockCs lock(m_cs);
if (-1 == i)
{
// Append at end of array.
i = m_cItems - 1;
}
// Can only append an item after an existing item.
// When array is empty, i can only be -1.
// When array is not empty, i must be index of a valid item.
// Note: i will be -1 when m_cItems is 0.
if ((0 == m_cItems && -1 != i) ||
(0 != m_cItems && (i < 0 || i >= m_cItems)))
{
throw CMemoryException(CMemoryException::index);
}
DBGASSERT((m_cItems <= m_cAlloc));
if (m_cItems >= m_cAlloc)
{
// Grow the array if necessary.
// This will also shift the elements, beginning with element 'i + 1',
// one element to the right.
SetSize(m_cAlloc + m_cGrow, i+1);
}
else
{
// Shift the contents of the array following the insertion
// point, one entry to the right.
for (int j = m_cItems; j > (i+1); j--)
{
m_rgItems[j] = m_rgItems[j-1];
}
}
// We've now appended an item.
m_cItems++;
// Set the value at the appended location.
// This assignment could throw an exception.
SetAt(item, i+1);
}
template <class T>
VOID
CArray<T>::Delete(
INT i
)
{
AutoLockCs lock(m_cs);
// Can only delete a valid item.
if (i < 0 || i >= m_cItems)
throw CMemoryException(CMemoryException::index);
// Shift memory to remove the item.
for (int j = i; j < (m_cItems - 1); j++)
{
m_rgItems[j] = m_rgItems[j+1];
}
// Now we have one less item.
m_cItems--;
// Shrink the array if it's required size is less than 2X the
// array's "growth" amount.
if ((m_cAlloc - m_cItems) > (2 * m_cGrow))
{
SetSize(m_cItems);
}
}
template <class T>
INT
CArray<T>::Find(
const T& key
)
{
AutoLockCs lock(m_cs);
for (INT i = 0; i < m_cItems; i++)
{
if (m_rgItems[i] == key)
{
return i;
}
}
return -1;
}
template <class T>
T
CArray<T>::GetAt(
INT i
) const
{
AutoLockCs lock(m_cs);
if (i < 0 || i >= m_cItems)
throw CMemoryException(CMemoryException::index);
return m_rgItems[i];
}
template <class T>
VOID
CArray<T>::SetAt(
const T& item,
INT i
)
{
AutoLockCs lock(m_cs);
if (i < 0 || i >= m_cAlloc)
throw CMemoryException(CMemoryException::index);
m_rgItems[i] = item;
}
// Returns: true = array was extended, false = no extension required.
template <class T>
bool
CArray<T>::SetAtGrow(
const T& item,
INT i
)
{
bool bGrow = false;
AutoLockCs lock(m_cs);
if (i >= m_cAlloc)
{
// Need to grow the array to accomodate the new item.
SetSize(i + m_cGrow);
bGrow = true;
}
// Set the new item value.
SetAt(item, i);
// Extend the count of "valid" items.
m_cItems = i + 1;
return bGrow;
}
template <class T>
VOID
CArray<T>::SetSize(
INT cEntries,
INT iShift // Pass -1 for "no shift".
)
{
AutoLockCs lock(m_cs);
// Don't allow an array of less than 1 element.
cEntries = MAX(1, cEntries);
T *pNew = new T[cEntries];
if (NULL == pNew)
throw CAllocException();
if (NULL != m_rgItems)
{
INT cCopy = MIN(cEntries, m_cItems);
INT j = 0;
for (INT i = 0; i < cCopy; i++, j++)
{
// Shift items [i..(n-1)] to [(i+1)..n]
if (iShift == j)
j++;
*(pNew + j) = m_rgItems[i];
}
}
delete[] m_rgItems;
m_rgItems = pNew;
m_cAlloc = cEntries;
}
template <class T>
class CQueueAsArray : public CArray<T>
{
public:
CQueueAsArray<T>(VOID) { }
~CQueueAsArray<T>(VOID) { }
VOID Add(T& item);
BOOL Remove(T& item);
private:
CQueueAsArray<T>(const CQueueAsArray<T>& rhs);
CQueueAsArray<T>& operator = (const CQueueAsArray<T>& rhs);
};
template <class T>
VOID
CQueueAsArray<T>::Add(
T& item
)
{
Append(item);
}
template <class T>
BOOL
CQueueAsArray<T>::Remove(
T& item
)
{
BOOL bResult = FALSE;
if (!IsEmpty())
{
INT i = UpperBound();
item = GetAt(i);
Delete(i);
bResult = TRUE;
}
return bResult;
}
#endif // _INC_DSKQUOTA_CARRAY_H