1
0
cuberite-2a/lib/cryptopp/queue.cpp

566 lines
12 KiB
C++
Raw Normal View History

// queue.cpp - written and placed in the public domain by Wei Dai
#include "pch.h"
#ifndef CRYPTOPP_IMPORTS
#include "queue.h"
#include "filters.h"
NAMESPACE_BEGIN(CryptoPP)
static const unsigned int s_maxAutoNodeSize = 16*1024;
// this class for use by ByteQueue only
class ByteQueueNode
{
public:
ByteQueueNode(size_t maxSize)
: buf(maxSize)
{
m_head = m_tail = 0;
next = 0;
}
inline size_t MaxSize() const {return buf.size();}
inline size_t CurrentSize() const
{
return m_tail-m_head;
}
inline bool UsedUp() const
{
return (m_head==MaxSize());
}
inline void Clear()
{
m_head = m_tail = 0;
}
inline size_t Put(const byte *begin, size_t length)
{
size_t l = STDMIN(length, MaxSize()-m_tail);
if (buf+m_tail != begin)
memcpy(buf+m_tail, begin, l);
m_tail += l;
return l;
}
inline size_t Peek(byte &outByte) const
{
if (m_tail==m_head)
return 0;
outByte=buf[m_head];
return 1;
}
inline size_t Peek(byte *target, size_t copyMax) const
{
size_t len = STDMIN(copyMax, m_tail-m_head);
memcpy(target, buf+m_head, len);
return len;
}
inline size_t CopyTo(BufferedTransformation &target, const std::string &channel=DEFAULT_CHANNEL) const
{
size_t len = m_tail-m_head;
target.ChannelPut(channel, buf+m_head, len);
return len;
}
inline size_t CopyTo(BufferedTransformation &target, size_t copyMax, const std::string &channel=DEFAULT_CHANNEL) const
{
size_t len = STDMIN(copyMax, m_tail-m_head);
target.ChannelPut(channel, buf+m_head, len);
return len;
}
inline size_t Get(byte &outByte)
{
size_t len = Peek(outByte);
m_head += len;
return len;
}
inline size_t Get(byte *outString, size_t getMax)
{
size_t len = Peek(outString, getMax);
m_head += len;
return len;
}
inline size_t TransferTo(BufferedTransformation &target, const std::string &channel=DEFAULT_CHANNEL)
{
size_t len = m_tail-m_head;
target.ChannelPutModifiable(channel, buf+m_head, len);
m_head = m_tail;
return len;
}
inline size_t TransferTo(BufferedTransformation &target, lword transferMax, const std::string &channel=DEFAULT_CHANNEL)
{
size_t len = UnsignedMin(m_tail-m_head, transferMax);
target.ChannelPutModifiable(channel, buf+m_head, len);
m_head += len;
return len;
}
inline size_t Skip(size_t skipMax)
{
size_t len = STDMIN(skipMax, m_tail-m_head);
m_head += len;
return len;
}
inline byte operator[](size_t i) const
{
return buf[m_head+i];
}
ByteQueueNode *next;
SecByteBlock buf;
size_t m_head, m_tail;
};
// ********************************************************
ByteQueue::ByteQueue(size_t nodeSize)
: m_lazyString(NULL), m_lazyLength(0)
{
SetNodeSize(nodeSize);
m_head = m_tail = new ByteQueueNode(m_nodeSize);
}
void ByteQueue::SetNodeSize(size_t nodeSize)
{
m_autoNodeSize = !nodeSize;
m_nodeSize = m_autoNodeSize ? 256 : nodeSize;
}
ByteQueue::ByteQueue(const ByteQueue &copy)
: m_lazyString(NULL)
{
CopyFrom(copy);
}
void ByteQueue::CopyFrom(const ByteQueue &copy)
{
m_lazyLength = 0;
m_autoNodeSize = copy.m_autoNodeSize;
m_nodeSize = copy.m_nodeSize;
m_head = m_tail = new ByteQueueNode(*copy.m_head);
for (ByteQueueNode *current=copy.m_head->next; current; current=current->next)
{
m_tail->next = new ByteQueueNode(*current);
m_tail = m_tail->next;
}
m_tail->next = NULL;
Put(copy.m_lazyString, copy.m_lazyLength);
}
ByteQueue::~ByteQueue()
{
Destroy();
}
void ByteQueue::Destroy()
{
for (ByteQueueNode *next, *current=m_head; current; current=next)
{
next=current->next;
delete current;
}
}
void ByteQueue::IsolatedInitialize(const NameValuePairs &parameters)
{
m_nodeSize = parameters.GetIntValueWithDefault("NodeSize", 256);
Clear();
}
lword ByteQueue::CurrentSize() const
{
lword size=0;
for (ByteQueueNode *current=m_head; current; current=current->next)
size += current->CurrentSize();
return size + m_lazyLength;
}
bool ByteQueue::IsEmpty() const
{
return m_head==m_tail && m_head->CurrentSize()==0 && m_lazyLength==0;
}
void ByteQueue::Clear()
{
for (ByteQueueNode *next, *current=m_head->next; current; current=next)
{
next=current->next;
delete current;
}
m_tail = m_head;
m_head->Clear();
m_head->next = NULL;
m_lazyLength = 0;
}
size_t ByteQueue::Put2(const byte *inString, size_t length, int messageEnd, bool blocking)
{
if (m_lazyLength > 0)
FinalizeLazyPut();
size_t len;
while ((len=m_tail->Put(inString, length)) < length)
{
inString += len;
length -= len;
if (m_autoNodeSize && m_nodeSize < s_maxAutoNodeSize)
do
{
m_nodeSize *= 2;
}
while (m_nodeSize < length && m_nodeSize < s_maxAutoNodeSize);
m_tail->next = new ByteQueueNode(STDMAX(m_nodeSize, length));
m_tail = m_tail->next;
}
return 0;
}
void ByteQueue::CleanupUsedNodes()
{
while (m_head != m_tail && m_head->UsedUp())
{
ByteQueueNode *temp=m_head;
m_head=m_head->next;
delete temp;
}
if (m_head->CurrentSize() == 0)
m_head->Clear();
}
void ByteQueue::LazyPut(const byte *inString, size_t size)
{
if (m_lazyLength > 0)
FinalizeLazyPut();
if (inString == m_tail->buf+m_tail->m_tail)
Put(inString, size);
else
{
m_lazyString = const_cast<byte *>(inString);
m_lazyLength = size;
m_lazyStringModifiable = false;
}
}
void ByteQueue::LazyPutModifiable(byte *inString, size_t size)
{
if (m_lazyLength > 0)
FinalizeLazyPut();
m_lazyString = inString;
m_lazyLength = size;
m_lazyStringModifiable = true;
}
void ByteQueue::UndoLazyPut(size_t size)
{
if (m_lazyLength < size)
throw InvalidArgument("ByteQueue: size specified for UndoLazyPut is too large");
m_lazyLength -= size;
}
void ByteQueue::FinalizeLazyPut()
{
size_t len = m_lazyLength;
m_lazyLength = 0;
if (len)
Put(m_lazyString, len);
}
size_t ByteQueue::Get(byte &outByte)
{
if (m_head->Get(outByte))
{
if (m_head->UsedUp())
CleanupUsedNodes();
return 1;
}
else if (m_lazyLength > 0)
{
outByte = *m_lazyString++;
m_lazyLength--;
return 1;
}
else
return 0;
}
size_t ByteQueue::Get(byte *outString, size_t getMax)
{
ArraySink sink(outString, getMax);
return (size_t)TransferTo(sink, getMax);
}
size_t ByteQueue::Peek(byte &outByte) const
{
if (m_head->Peek(outByte))
return 1;
else if (m_lazyLength > 0)
{
outByte = *m_lazyString;
return 1;
}
else
return 0;
}
size_t ByteQueue::Peek(byte *outString, size_t peekMax) const
{
ArraySink sink(outString, peekMax);
return (size_t)CopyTo(sink, peekMax);
}
size_t ByteQueue::TransferTo2(BufferedTransformation &target, lword &transferBytes, const std::string &channel, bool blocking)
{
if (blocking)
{
lword bytesLeft = transferBytes;
for (ByteQueueNode *current=m_head; bytesLeft && current; current=current->next)
bytesLeft -= current->TransferTo(target, bytesLeft, channel);
CleanupUsedNodes();
size_t len = (size_t)STDMIN(bytesLeft, (lword)m_lazyLength);
if (len)
{
if (m_lazyStringModifiable)
target.ChannelPutModifiable(channel, m_lazyString, len);
else
target.ChannelPut(channel, m_lazyString, len);
m_lazyString += len;
m_lazyLength -= len;
bytesLeft -= len;
}
transferBytes -= bytesLeft;
return 0;
}
else
{
Walker walker(*this);
size_t blockedBytes = walker.TransferTo2(target, transferBytes, channel, blocking);
Skip(transferBytes);
return blockedBytes;
}
}
size_t ByteQueue::CopyRangeTo2(BufferedTransformation &target, lword &begin, lword end, const std::string &channel, bool blocking) const
{
Walker walker(*this);
walker.Skip(begin);
lword transferBytes = end-begin;
size_t blockedBytes = walker.TransferTo2(target, transferBytes, channel, blocking);
begin += transferBytes;
return blockedBytes;
}
void ByteQueue::Unget(byte inByte)
{
Unget(&inByte, 1);
}
void ByteQueue::Unget(const byte *inString, size_t length)
{
size_t len = STDMIN(length, m_head->m_head);
length -= len;
m_head->m_head -= len;
memcpy(m_head->buf + m_head->m_head, inString + length, len);
if (length > 0)
{
ByteQueueNode *newHead = new ByteQueueNode(length);
newHead->next = m_head;
m_head = newHead;
m_head->Put(inString, length);
}
}
const byte * ByteQueue::Spy(size_t &contiguousSize) const
{
contiguousSize = m_head->m_tail - m_head->m_head;
if (contiguousSize == 0 && m_lazyLength > 0)
{
contiguousSize = m_lazyLength;
return m_lazyString;
}
else
return m_head->buf + m_head->m_head;
}
byte * ByteQueue::CreatePutSpace(size_t &size)
{
if (m_lazyLength > 0)
FinalizeLazyPut();
if (m_tail->m_tail == m_tail->MaxSize())
{
m_tail->next = new ByteQueueNode(STDMAX(m_nodeSize, size));
m_tail = m_tail->next;
}
size = m_tail->MaxSize() - m_tail->m_tail;
return m_tail->buf + m_tail->m_tail;
}
ByteQueue & ByteQueue::operator=(const ByteQueue &rhs)
{
Destroy();
CopyFrom(rhs);
return *this;
}
bool ByteQueue::operator==(const ByteQueue &rhs) const
{
const lword currentSize = CurrentSize();
if (currentSize != rhs.CurrentSize())
return false;
Walker walker1(*this), walker2(rhs);
byte b1, b2;
while (walker1.Get(b1) && walker2.Get(b2))
if (b1 != b2)
return false;
return true;
}
byte ByteQueue::operator[](lword i) const
{
for (ByteQueueNode *current=m_head; current; current=current->next)
{
if (i < current->CurrentSize())
return (*current)[(size_t)i];
i -= current->CurrentSize();
}
assert(i < m_lazyLength);
return m_lazyString[i];
}
void ByteQueue::swap(ByteQueue &rhs)
{
std::swap(m_autoNodeSize, rhs.m_autoNodeSize);
std::swap(m_nodeSize, rhs.m_nodeSize);
std::swap(m_head, rhs.m_head);
std::swap(m_tail, rhs.m_tail);
std::swap(m_lazyString, rhs.m_lazyString);
std::swap(m_lazyLength, rhs.m_lazyLength);
std::swap(m_lazyStringModifiable, rhs.m_lazyStringModifiable);
}
// ********************************************************
void ByteQueue::Walker::IsolatedInitialize(const NameValuePairs &parameters)
{
m_node = m_queue.m_head;
m_position = 0;
m_offset = 0;
m_lazyString = m_queue.m_lazyString;
m_lazyLength = m_queue.m_lazyLength;
}
size_t ByteQueue::Walker::Get(byte &outByte)
{
ArraySink sink(&outByte, 1);
return (size_t)TransferTo(sink, 1);
}
size_t ByteQueue::Walker::Get(byte *outString, size_t getMax)
{
ArraySink sink(outString, getMax);
return (size_t)TransferTo(sink, getMax);
}
size_t ByteQueue::Walker::Peek(byte &outByte) const
{
ArraySink sink(&outByte, 1);
return (size_t)CopyTo(sink, 1);
}
size_t ByteQueue::Walker::Peek(byte *outString, size_t peekMax) const
{
ArraySink sink(outString, peekMax);
return (size_t)CopyTo(sink, peekMax);
}
size_t ByteQueue::Walker::TransferTo2(BufferedTransformation &target, lword &transferBytes, const std::string &channel, bool blocking)
{
lword bytesLeft = transferBytes;
size_t blockedBytes = 0;
while (m_node)
{
size_t len = (size_t)STDMIN(bytesLeft, (lword)m_node->CurrentSize()-m_offset);
blockedBytes = target.ChannelPut2(channel, m_node->buf+m_node->m_head+m_offset, len, 0, blocking);
if (blockedBytes)
goto done;
m_position += len;
bytesLeft -= len;
if (!bytesLeft)
{
m_offset += len;
goto done;
}
m_node = m_node->next;
m_offset = 0;
}
if (bytesLeft && m_lazyLength)
{
size_t len = (size_t)STDMIN(bytesLeft, (lword)m_lazyLength);
blockedBytes = target.ChannelPut2(channel, m_lazyString, len, 0, blocking);
if (blockedBytes)
goto done;
m_lazyString += len;
m_lazyLength -= len;
bytesLeft -= len;
}
done:
transferBytes -= bytesLeft;
return blockedBytes;
}
size_t ByteQueue::Walker::CopyRangeTo2(BufferedTransformation &target, lword &begin, lword end, const std::string &channel, bool blocking) const
{
Walker walker(*this);
walker.Skip(begin);
lword transferBytes = end-begin;
size_t blockedBytes = walker.TransferTo2(target, transferBytes, channel, blocking);
begin += transferBytes;
return blockedBytes;
}
NAMESPACE_END
#endif