libnative-utilities/include/raknet/DS_Queue.hpp
2024-08-15 18:40:30 +08:00

462 lines
11 KiB
C++

/*
* Copyright (c) 2014, Oculus VR, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*
*/
/// \file DS_Queue.h
/// \internal
/// \brief A queue used by RakNet.
///
#ifndef __QUEUE_H
#define __QUEUE_H
// Template classes have to have all the code in the header file
#include "RakAssert.hpp"
#include "Export.hpp"
#include "RakMemoryOverride.hpp"
/// The namespace DataStructures was only added to avoid compiler errors for commonly named data structures
/// As these data structures are stand-alone, you can use them outside of RakNet for your own projects if you wish.
namespace DataStructures
{
/// \brief A queue implemented as an array with a read and write index.
template <class queue_type>
class RAK_DLL_EXPORT Queue
{
public:
Queue();
~Queue();
Queue( Queue& original_copy );
bool operator= ( const Queue& original_copy );
void Push( const queue_type& input, const char *file, unsigned int line );
void PushAtHead( const queue_type& input, unsigned index, const char *file, unsigned int line );
queue_type& operator[] ( unsigned int position ) const; // Not a normal thing you do with a queue but can be used for efficiency
void RemoveAtIndex( unsigned int position ); // Not a normal thing you do with a queue but can be used for efficiency
inline queue_type Peek( void ) const;
inline queue_type PeekTail( void ) const;
inline queue_type Pop( void );
inline queue_type PopTail( void );
// Debug: Set pointer to 0, for memory leak detection
inline queue_type PopDeref( void );
inline unsigned int Size( void ) const;
inline bool IsEmpty(void) const;
inline unsigned int AllocationSize( void ) const;
inline void Clear( const char *file, unsigned int line );
void Compress( const char *file, unsigned int line );
bool Find ( const queue_type& q );
void ClearAndForceAllocation( int size, const char *file, unsigned int line ); // Force a memory allocation to a certain larger size
private:
queue_type* array;
unsigned int head; // Array index for the head of the queue
unsigned int tail; // Array index for the tail of the queue
unsigned int allocation_size;
};
template <class queue_type>
inline unsigned int Queue<queue_type>::Size( void ) const
{
if ( head <= tail )
return tail -head;
else
return allocation_size -head + tail;
}
template <class queue_type>
inline bool Queue<queue_type>::IsEmpty(void) const
{
return head==tail;
}
template <class queue_type>
inline unsigned int Queue<queue_type>::AllocationSize( void ) const
{
return allocation_size;
}
template <class queue_type>
Queue<queue_type>::Queue()
{
//allocation_size = 16;
//array = RakNet::OP_NEW_ARRAY<queue_type>(allocation_size, _FILE_AND_LINE_ );
allocation_size = 0;
array=0;
head = 0;
tail = 0;
}
template <class queue_type>
Queue<queue_type>::~Queue()
{
if (allocation_size>0)
RakNet::OP_DELETE_ARRAY(array, _FILE_AND_LINE_);
}
template <class queue_type>
inline queue_type Queue<queue_type>::Pop( void )
{
#ifdef _DEBUG
RakAssert( head != tail);
#endif
//head=(head+1) % allocation_size;
if ( ++head == allocation_size )
head = 0;
if ( head == 0 )
return ( queue_type ) array[ allocation_size -1 ];
return ( queue_type ) array[ head -1 ];
}
template <class queue_type>
inline queue_type Queue<queue_type>::PopTail( void )
{
#ifdef _DEBUG
RakAssert( head != tail );
#endif
if (tail!=0)
{
--tail;
return ( queue_type ) array[ tail ];
}
else
{
tail=allocation_size-1;
return ( queue_type ) array[ tail ];
}
}
template <class queue_type>
inline queue_type Queue<queue_type>::PopDeref( void )
{
if ( ++head == allocation_size )
head = 0;
queue_type q;
if ( head == 0 )
{
q=array[ allocation_size -1 ];
array[ allocation_size -1 ]=0;
return q;
}
q=array[ head -1 ];
array[ head -1 ]=0;
return q;
}
template <class queue_type>
void Queue<queue_type>::PushAtHead( const queue_type& input, unsigned index, const char *file, unsigned int line )
{
RakAssert(index <= Size());
// Just force a reallocation, will be overwritten
Push(input, file, line );
if (Size()==1)
return;
unsigned writeIndex, readIndex, trueWriteIndex, trueReadIndex;
writeIndex=Size()-1;
readIndex=writeIndex-1;
while (readIndex >= index)
{
if ( head + writeIndex >= allocation_size )
trueWriteIndex = head + writeIndex - allocation_size;
else
trueWriteIndex = head + writeIndex;
if ( head + readIndex >= allocation_size )
trueReadIndex = head + readIndex - allocation_size;
else
trueReadIndex = head + readIndex;
array[trueWriteIndex]=array[trueReadIndex];
if (readIndex==0)
break;
writeIndex--;
readIndex--;
}
if ( head + index >= allocation_size )
trueWriteIndex = head + index - allocation_size;
else
trueWriteIndex = head + index;
array[trueWriteIndex]=input;
}
template <class queue_type>
inline queue_type Queue<queue_type>::Peek( void ) const
{
#ifdef _DEBUG
RakAssert( head != tail );
#endif
return ( queue_type ) array[ head ];
}
template <class queue_type>
inline queue_type Queue<queue_type>::PeekTail( void ) const
{
#ifdef _DEBUG
RakAssert( head != tail );
#endif
if (tail!=0)
return ( queue_type ) array[ tail-1 ];
else
return ( queue_type ) array[ allocation_size-1 ];
}
template <class queue_type>
void Queue<queue_type>::Push( const queue_type& input, const char *file, unsigned int line )
{
if ( allocation_size == 0 )
{
array = RakNet::OP_NEW_ARRAY<queue_type>(16, file, line );
head = 0;
tail = 1;
array[ 0 ] = input;
allocation_size = 16;
return ;
}
array[ tail++ ] = input;
if ( tail == allocation_size )
tail = 0;
if ( tail == head )
{
// unsigned int index=tail;
// Need to allocate more memory.
queue_type * new_array;
new_array = RakNet::OP_NEW_ARRAY<queue_type>((int)allocation_size * 2, file, line );
#ifdef _DEBUG
RakAssert( new_array );
#endif
if (new_array==0)
return;
for ( unsigned int counter = 0; counter < allocation_size; ++counter )
new_array[ counter ] = array[ ( head + counter ) % ( allocation_size ) ];
head = 0;
tail = allocation_size;
allocation_size *= 2;
// Delete the old array and move the pointer to the new array
RakNet::OP_DELETE_ARRAY(array, file, line);
array = new_array;
}
}
template <class queue_type>
Queue<queue_type>::Queue( Queue& original_copy )
{
// Allocate memory for copy
if ( original_copy.Size() == 0 )
{
allocation_size = 0;
}
else
{
array = RakNet::OP_NEW_ARRAY<queue_type >( original_copy.Size() + 1 , _FILE_AND_LINE_ );
for ( unsigned int counter = 0; counter < original_copy.Size(); ++counter )
array[ counter ] = original_copy.array[ ( original_copy.head + counter ) % ( original_copy.allocation_size ) ];
head = 0;
tail = original_copy.Size();
allocation_size = original_copy.Size() + 1;
}
}
template <class queue_type>
bool Queue<queue_type>::operator= ( const Queue& original_copy )
{
if ( ( &original_copy ) == this )
return false;
Clear(_FILE_AND_LINE_);
// Allocate memory for copy
if ( original_copy.Size() == 0 )
{
allocation_size = 0;
}
else
{
array = RakNet::OP_NEW_ARRAY<queue_type >( original_copy.Size() + 1 , _FILE_AND_LINE_ );
for ( unsigned int counter = 0; counter < original_copy.Size(); ++counter )
array[ counter ] = original_copy.array[ ( original_copy.head + counter ) % ( original_copy.allocation_size ) ];
head = 0;
tail = original_copy.Size();
allocation_size = original_copy.Size() + 1;
}
return true;
}
template <class queue_type>
inline void Queue<queue_type>::Clear ( const char *file, unsigned int line )
{
if ( allocation_size == 0 )
return ;
if (allocation_size > 32)
{
RakNet::OP_DELETE_ARRAY(array, file, line);
allocation_size = 0;
}
head = 0;
tail = 0;
}
template <class queue_type>
void Queue<queue_type>::Compress ( const char *file, unsigned int line )
{
queue_type* new_array;
unsigned int newAllocationSize;
if (allocation_size==0)
return;
newAllocationSize=1;
while (newAllocationSize <= Size())
newAllocationSize<<=1; // Must be a better way to do this but I'm too dumb to figure it out quickly :)
new_array = RakNet::OP_NEW_ARRAY<queue_type >(newAllocationSize, file, line );
for (unsigned int counter=0; counter < Size(); ++counter)
new_array[counter] = array[(head + counter)%(allocation_size)];
tail=Size();
allocation_size=newAllocationSize;
head=0;
// Delete the old array and move the pointer to the new array
RakNet::OP_DELETE_ARRAY(array, file, line);
array=new_array;
}
template <class queue_type>
bool Queue<queue_type>::Find ( const queue_type &q )
{
if ( allocation_size == 0 )
return false;
unsigned int counter = head;
while ( counter != tail )
{
if ( array[ counter ] == q )
return true;
counter = ( counter + 1 ) % allocation_size;
}
return false;
}
template <class queue_type>
void Queue<queue_type>::ClearAndForceAllocation( int size, const char *file, unsigned int line )
{
RakNet::OP_DELETE_ARRAY(array, file, line);
if (size>0)
array = RakNet::OP_NEW_ARRAY<queue_type>(size, file, line );
else
array=0;
allocation_size = size;
head = 0;
tail = 0;
}
template <class queue_type>
inline queue_type& Queue<queue_type>::operator[] ( unsigned int position ) const
{
#ifdef _DEBUG
RakAssert( position < Size() );
#endif
//return array[(head + position) % allocation_size];
if ( head + position >= allocation_size )
return array[ head + position - allocation_size ];
else
return array[ head + position ];
}
template <class queue_type>
void Queue<queue_type>::RemoveAtIndex( unsigned int position )
{
#ifdef _DEBUG
RakAssert( position < Size() );
RakAssert( head != tail );
#endif
if ( head == tail || position >= Size() )
return ;
unsigned int index;
unsigned int next;
//index = (head + position) % allocation_size;
if ( head + position >= allocation_size )
index = head + position - allocation_size;
else
index = head + position;
//next = (index + 1) % allocation_size;
next = index + 1;
if ( next == allocation_size )
next = 0;
while ( next != tail )
{
// Overwrite the previous element
array[ index ] = array[ next ];
index = next;
//next = (next + 1) % allocation_size;
if ( ++next == allocation_size )
next = 0;
}
// Move the tail back
if ( tail == 0 )
tail = allocation_size - 1;
else
--tail;
}
} // End namespace
#endif