Files
unison/src/network/model/buffer.cc
2015-08-05 15:20:10 -04:00

1211 lines
31 KiB
C++

/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/*
* Copyright (c) 2005,2006,2007 INRIA
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation;
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Author: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>
*/
#include "buffer.h"
#include "ns3/assert.h"
#include "ns3/log.h"
#define LOG_INTERNAL_STATE(y) \
NS_LOG_LOGIC (y << "start="<<m_start<<", end="<<m_end<<", zero start="<<m_zeroAreaStart<< \
", zero end="<<m_zeroAreaEnd<<", count="<<m_data->m_count<<", size="<<m_data->m_size<< \
", dirty start="<<m_data->m_dirtyStart<<", dirty end="<<m_data->m_dirtyEnd)
namespace {
/**
* \ingroup packet
* \brief Zero-filled buffer.
*/
static struct Zeroes
{
Zeroes ()
: size (1000)
{
memset (buffer, 0, size);
}
char buffer[1000]; //!< buffer containing zero values
const uint32_t size; //!< buffer size
} g_zeroes; //!< Zero-filled buffer
}
namespace ns3 {
NS_LOG_COMPONENT_DEFINE ("Buffer");
uint32_t Buffer::g_recommendedStart = 0;
#ifdef BUFFER_FREE_LIST
/* The following macros are pretty evil but they are needed to allow us to
* keep track of 3 possible states for the g_freeList variable:
* - uninitialized means that no one has created a buffer yet
* so no one has created the associated free list (it is created
* on-demand when the first buffer is created)
* - initialized means that the free list exists and is valid
* - destroyed means that the static destructors of this compilation unit
* have run so, the free list has been cleared from its content
* The key is that in destroyed state, we are careful not re-create it
* which is a typical weakness of lazy evaluation schemes which use
* '0' as a special value to indicate both un-initialized and destroyed.
* Note that it is important to use '0' as the marker for un-initialized state
* because the variable holding this state information is initialized to zero
* which the compiler assigns to zero-memory which is initialized to _zero_
* before the constructors run so this ensures perfect handling of crazy
* constructor orderings.
*/
#define MAGIC_DESTROYED (~(long) 0)
#define IS_UNINITIALIZED(x) (x == (Buffer::FreeList*)0)
#define IS_DESTROYED(x) (x == (Buffer::FreeList*)MAGIC_DESTROYED)
#define IS_INITIALIZED(x) (!IS_UNINITIALIZED (x) && !IS_DESTROYED (x))
#define DESTROYED ((Buffer::FreeList*)MAGIC_DESTROYED)
#define UNINITIALIZED ((Buffer::FreeList*)0)
uint32_t Buffer::g_maxSize = 0;
Buffer::FreeList *Buffer::g_freeList = 0;
struct Buffer::LocalStaticDestructor Buffer::g_localStaticDestructor;
Buffer::LocalStaticDestructor::~LocalStaticDestructor(void)
{
NS_LOG_FUNCTION (this);
if (IS_INITIALIZED (g_freeList))
{
for (Buffer::FreeList::iterator i = g_freeList->begin ();
i != g_freeList->end (); i++)
{
Buffer::Deallocate (*i);
}
delete g_freeList;
g_freeList = DESTROYED;
}
}
void
Buffer::Recycle (struct Buffer::Data *data)
{
NS_LOG_FUNCTION (data);
NS_ASSERT (data->m_count == 0);
NS_ASSERT (!IS_UNINITIALIZED (g_freeList));
g_maxSize = std::max (g_maxSize, data->m_size);
/* feed into free list */
if (data->m_size < g_maxSize ||
IS_DESTROYED (g_freeList) ||
g_freeList->size () > 1000)
{
Buffer::Deallocate (data);
}
else
{
NS_ASSERT (IS_INITIALIZED (g_freeList));
g_freeList->push_back (data);
}
}
Buffer::Data *
Buffer::Create (uint32_t dataSize)
{
NS_LOG_FUNCTION (dataSize);
/* try to find a buffer correctly sized. */
if (IS_UNINITIALIZED (g_freeList))
{
g_freeList = new Buffer::FreeList ();
}
else if (IS_INITIALIZED (g_freeList))
{
while (!g_freeList->empty ())
{
struct Buffer::Data *data = g_freeList->back ();
g_freeList->pop_back ();
if (data->m_size >= dataSize)
{
data->m_count = 1;
return data;
}
Buffer::Deallocate (data);
}
}
struct Buffer::Data *data = Buffer::Allocate (dataSize);
NS_ASSERT (data->m_count == 1);
return data;
}
#else /* BUFFER_FREE_LIST */
void
Buffer::Recycle (struct Buffer::Data *data)
{
NS_LOG_FUNCTION (data);
NS_ASSERT (data->m_count == 0);
Deallocate (data);
}
Buffer::Data *
Buffer::Create (uint32_t size)
{
NS_LOG_FUNCTION (size);
return Allocate (size);
}
#endif /* BUFFER_FREE_LIST */
struct Buffer::Data *
Buffer::Allocate (uint32_t reqSize)
{
NS_LOG_FUNCTION (reqSize);
if (reqSize == 0)
{
reqSize = 1;
}
NS_ASSERT (reqSize >= 1);
uint32_t size = reqSize - 1 + sizeof (struct Buffer::Data);
uint8_t *b = new uint8_t [size];
struct Buffer::Data *data = reinterpret_cast<struct Buffer::Data*>(b);
data->m_size = reqSize;
data->m_count = 1;
return data;
}
void
Buffer::Deallocate (struct Buffer::Data *data)
{
NS_LOG_FUNCTION (data);
NS_ASSERT (data->m_count == 0);
uint8_t *buf = reinterpret_cast<uint8_t *> (data);
delete [] buf;
}
Buffer::Buffer ()
{
NS_LOG_FUNCTION (this);
Initialize (0);
}
Buffer::Buffer (uint32_t dataSize)
{
NS_LOG_FUNCTION (this << dataSize);
Initialize (dataSize);
}
Buffer::Buffer (uint32_t dataSize, bool initialize)
{
NS_LOG_FUNCTION (this << dataSize << initialize);
if (initialize == true)
{
Initialize (dataSize);
}
}
bool
Buffer::CheckInternalState (void) const
{
NS_LOG_FUNCTION (this);
#if 0
// If you want to modify any code in this file, enable this checking code.
// Otherwise, there is not much point is enabling it because the
// current implementation has been fairly seriously tested and the cost
// of this constant checking is pretty high, even for a debug build.
bool offsetsOk =
m_start <= m_zeroAreaStart &&
m_zeroAreaStart <= m_zeroAreaEnd &&
m_zeroAreaEnd <= m_end;
bool dirtyOk =
m_start >= m_data->m_dirtyStart &&
m_end <= m_data->m_dirtyEnd;
bool internalSizeOk = m_end - (m_zeroAreaEnd - m_zeroAreaStart) <= m_data->m_size &&
m_start <= m_data->m_size &&
m_zeroAreaStart <= m_data->m_size;
bool ok = m_data->m_count > 0 && offsetsOk && dirtyOk && internalSizeOk;
if (!ok)
{
LOG_INTERNAL_STATE ("check " << this <<
", " << (offsetsOk ? "true" : "false") <<
", " << (dirtyOk ? "true" : "false") <<
", " << (internalSizeOk ? "true" : "false") << " ");
}
return ok;
#else
return true;
#endif
}
void
Buffer::Initialize (uint32_t zeroSize)
{
NS_LOG_FUNCTION (this << zeroSize);
m_data = Buffer::Create (0);
m_start = std::min (m_data->m_size, g_recommendedStart);
m_maxZeroAreaStart = m_start;
m_zeroAreaStart = m_start;
m_zeroAreaEnd = m_zeroAreaStart + zeroSize;
m_end = m_zeroAreaEnd;
m_data->m_dirtyStart = m_start;
m_data->m_dirtyEnd = m_end;
NS_ASSERT (CheckInternalState ());
}
Buffer &
Buffer::operator = (Buffer const&o)
{
NS_ASSERT (CheckInternalState ());
if (m_data != o.m_data)
{
// not assignment to self.
m_data->m_count--;
if (m_data->m_count == 0)
{
Recycle (m_data);
}
m_data = o.m_data;
m_data->m_count++;
}
g_recommendedStart = std::max (g_recommendedStart, m_maxZeroAreaStart);
m_maxZeroAreaStart = o.m_maxZeroAreaStart;
m_zeroAreaStart = o.m_zeroAreaStart;
m_zeroAreaEnd = o.m_zeroAreaEnd;
m_start = o.m_start;
m_end = o.m_end;
NS_ASSERT (CheckInternalState ());
return *this;
}
Buffer::~Buffer ()
{
NS_LOG_FUNCTION (this);
NS_ASSERT (CheckInternalState ());
g_recommendedStart = std::max (g_recommendedStart, m_maxZeroAreaStart);
m_data->m_count--;
if (m_data->m_count == 0)
{
Recycle (m_data);
}
}
uint32_t
Buffer::GetInternalSize (void) const
{
NS_LOG_FUNCTION (this);
return m_zeroAreaStart - m_start + m_end - m_zeroAreaEnd;
}
uint32_t
Buffer::GetInternalEnd (void) const
{
NS_LOG_FUNCTION (this);
return m_end - (m_zeroAreaEnd - m_zeroAreaStart);
}
void
Buffer::AddAtStart (uint32_t start)
{
NS_LOG_FUNCTION (this << start);
NS_ASSERT (CheckInternalState ());
bool isDirty = m_data->m_count > 1 && m_start > m_data->m_dirtyStart;
if (m_start >= start && !isDirty)
{
/* enough space in the buffer and not dirty.
* To add: |..|
* Before: |*****---------***|
* After: |***..---------***|
*/
NS_ASSERT (m_data->m_count == 1 || m_start == m_data->m_dirtyStart);
m_start -= start;
// update dirty area
m_data->m_dirtyStart = m_start;
}
else
{
uint32_t newSize = GetInternalSize () + start;
struct Buffer::Data *newData = Buffer::Create (newSize);
memcpy (newData->m_data + start, m_data->m_data + m_start, GetInternalSize ());
m_data->m_count--;
if (m_data->m_count == 0)
{
Buffer::Recycle (m_data);
}
m_data = newData;
int32_t delta = start - m_start;
m_start += delta;
m_zeroAreaStart += delta;
m_zeroAreaEnd += delta;
m_end += delta;
m_start -= start;
// update dirty area
m_data->m_dirtyStart = m_start;
m_data->m_dirtyEnd = m_end;
}
m_maxZeroAreaStart = std::max (m_maxZeroAreaStart, m_zeroAreaStart);
LOG_INTERNAL_STATE ("add start=" << start << ", ");
NS_ASSERT (CheckInternalState ());
}
void
Buffer::AddAtEnd (uint32_t end)
{
NS_LOG_FUNCTION (this << end);
NS_ASSERT (CheckInternalState ());
bool isDirty = m_data->m_count > 1 && m_end < m_data->m_dirtyEnd;
if (GetInternalEnd () + end <= m_data->m_size && !isDirty)
{
/* enough space in buffer and not dirty
* Add: |...|
* Before: |**----*****|
* After: |**----...**|
*/
NS_ASSERT (m_data->m_count == 1 || m_end == m_data->m_dirtyEnd);
m_end += end;
// update dirty area.
m_data->m_dirtyEnd = m_end;
}
else
{
uint32_t newSize = GetInternalSize () + end;
struct Buffer::Data *newData = Buffer::Create (newSize);
memcpy (newData->m_data, m_data->m_data + m_start, GetInternalSize ());
m_data->m_count--;
if (m_data->m_count == 0)
{
Buffer::Recycle (m_data);
}
m_data = newData;
int32_t delta = -m_start;
m_zeroAreaStart += delta;
m_zeroAreaEnd += delta;
m_end += delta;
m_start += delta;
m_end += end;
// update dirty area
m_data->m_dirtyStart = m_start;
m_data->m_dirtyEnd = m_end;
}
m_maxZeroAreaStart = std::max (m_maxZeroAreaStart, m_zeroAreaStart);
LOG_INTERNAL_STATE ("add end=" << end << ", ");
NS_ASSERT (CheckInternalState ());
}
void
Buffer::AddAtEnd (const Buffer &o)
{
NS_LOG_FUNCTION (this << &o);
if (m_data->m_count == 1 &&
m_end == m_zeroAreaEnd &&
m_end == m_data->m_dirtyEnd &&
o.m_start == o.m_zeroAreaStart &&
o.m_zeroAreaEnd - o.m_zeroAreaStart > 0)
{
/**
* This is an optimization which kicks in when
* we attempt to aggregate two buffers which contain
* adjacent zero areas.
*/
uint32_t zeroSize = o.m_zeroAreaEnd - o.m_zeroAreaStart;
m_zeroAreaEnd += zeroSize;
m_end = m_zeroAreaEnd;
m_data->m_dirtyEnd = m_zeroAreaEnd;
uint32_t endData = o.m_end - o.m_zeroAreaEnd;
AddAtEnd (endData);
Buffer::Iterator dst = End ();
dst.Prev (endData);
Buffer::Iterator src = o.End ();
src.Prev (endData);
dst.Write (src, o.End ());
NS_ASSERT (CheckInternalState ());
return;
}
Buffer dst = CreateFullCopy ();
Buffer src = o.CreateFullCopy ();
dst.AddAtEnd (src.GetSize ());
Buffer::Iterator destStart = dst.End ();
destStart.Prev (src.GetSize ());
destStart.Write (src.Begin (), src.End ());
*this = dst;
NS_ASSERT (CheckInternalState ());
}
void
Buffer::RemoveAtStart (uint32_t start)
{
NS_LOG_FUNCTION (this << start);
NS_ASSERT (CheckInternalState ());
uint32_t newStart = m_start + start;
if (newStart <= m_zeroAreaStart)
{
/* only remove start of buffer
*/
m_start = newStart;
}
else if (newStart <= m_zeroAreaEnd)
{
/* remove start of buffer _and_ start of zero area
*/
uint32_t delta = newStart - m_zeroAreaStart;
m_start = m_zeroAreaStart;
m_zeroAreaEnd -= delta;
m_end -= delta;
}
else if (newStart <= m_end)
{
/* remove start of buffer, complete zero area, and part
* of end of buffer
*/
NS_ASSERT (m_end >= start);
uint32_t zeroSize = m_zeroAreaEnd - m_zeroAreaStart;
m_start = newStart - zeroSize;
m_end -= zeroSize;
m_zeroAreaStart = m_start;
m_zeroAreaEnd = m_start;
}
else
{
/* remove all buffer */
m_end -= m_zeroAreaEnd - m_zeroAreaStart;
m_start = m_end;
m_zeroAreaEnd = m_end;
m_zeroAreaStart = m_end;
}
m_maxZeroAreaStart = std::max (m_maxZeroAreaStart, m_zeroAreaStart);
LOG_INTERNAL_STATE ("rem start=" << start << ", ");
NS_ASSERT (CheckInternalState ());
}
void
Buffer::RemoveAtEnd (uint32_t end)
{
NS_LOG_FUNCTION (this << end);
NS_ASSERT (CheckInternalState ());
uint32_t newEnd = m_end - std::min (end, m_end - m_start);
if (newEnd > m_zeroAreaEnd)
{
/* remove part of end of buffer */
m_end = newEnd;
}
else if (newEnd > m_zeroAreaStart)
{
/* remove end of buffer, part of zero area */
m_end = newEnd;
m_zeroAreaEnd = newEnd;
}
else if (newEnd > m_start)
{
/* remove end of buffer, zero area, part of start of buffer */
m_end = newEnd;
m_zeroAreaEnd = newEnd;
m_zeroAreaStart = newEnd;
}
else
{
/* remove all buffer */
m_end = m_start;
m_zeroAreaEnd = m_start;
m_zeroAreaStart = m_start;
}
m_maxZeroAreaStart = std::max (m_maxZeroAreaStart, m_zeroAreaStart);
LOG_INTERNAL_STATE ("rem end=" << end << ", ");
NS_ASSERT (CheckInternalState ());
}
Buffer
Buffer::CreateFragment (uint32_t start, uint32_t length) const
{
NS_LOG_FUNCTION (this << start << length);
NS_ASSERT (CheckInternalState ());
Buffer tmp = *this;
tmp.RemoveAtStart (start);
tmp.RemoveAtEnd (GetSize () - (start + length));
NS_ASSERT (CheckInternalState ());
return tmp;
}
Buffer
Buffer::CreateFullCopy (void) const
{
NS_LOG_FUNCTION (this);
NS_ASSERT (CheckInternalState ());
if (m_zeroAreaEnd - m_zeroAreaStart != 0)
{
Buffer tmp;
tmp.AddAtStart (m_zeroAreaEnd - m_zeroAreaStart);
tmp.Begin ().WriteU8 (0, m_zeroAreaEnd - m_zeroAreaStart);
uint32_t dataStart = m_zeroAreaStart - m_start;
tmp.AddAtStart (dataStart);
tmp.Begin ().Write (m_data->m_data+m_start, dataStart);
uint32_t dataEnd = m_end - m_zeroAreaEnd;
tmp.AddAtEnd (dataEnd);
Buffer::Iterator i = tmp.End ();
i.Prev (dataEnd);
i.Write (m_data->m_data+m_zeroAreaStart,dataEnd);
NS_ASSERT (tmp.CheckInternalState ());
return tmp;
}
NS_ASSERT (CheckInternalState ());
return *this;
}
uint32_t
Buffer::GetSerializedSize (void) const
{
NS_LOG_FUNCTION (this);
uint32_t dataStart = (m_zeroAreaStart - m_start + 3) & (~0x3);
uint32_t dataEnd = (m_end - m_zeroAreaEnd + 3) & (~0x3);
// total size 4-bytes for dataStart length
// + X number of bytes for dataStart
// + 4-bytes for dataEnd length
// + X number of bytes for dataEnd
uint32_t sz = sizeof (uint32_t)
+ sizeof (uint32_t)
+ dataStart
+ sizeof (uint32_t)
+ dataEnd;
return sz;
}
uint32_t
Buffer::Serialize (uint8_t* buffer, uint32_t maxSize) const
{
NS_LOG_FUNCTION (this << &buffer << maxSize);
uint32_t* p = reinterpret_cast<uint32_t *> (buffer);
uint32_t size = 0;
// Add the zero data length
if (size + 4 <= maxSize)
{
size += 4;
*p++ = m_zeroAreaEnd - m_zeroAreaStart;
}
else
{
return 0;
}
// Add the length of actual start data
uint32_t dataStartLength = m_zeroAreaStart - m_start;
if (size + 4 <= maxSize)
{
size += 4;
*p++ = dataStartLength;
}
else
{
return 0;
}
// Add the actual data
if (size + ((dataStartLength + 3) & (~3)) <= maxSize)
{
size += (dataStartLength + 3) & (~3);
memcpy (p, m_data->m_data + m_start, dataStartLength);
p += (((dataStartLength + 3) & (~3))/4); // Advance p, insuring 4 byte boundary
}
else
{
return 0;
}
// Add the length of the actual end data
uint32_t dataEndLength = m_end - m_zeroAreaEnd;
if (size + 4 <= maxSize)
{
size += 4;
*p++ = dataEndLength;
}
else
{
return 0;
}
// Add the actual data
if (size + ((dataEndLength + 3) & (~3)) <= maxSize)
{
size += (dataEndLength + 3) & (~3);
memcpy (p, m_data->m_data+m_zeroAreaStart,dataEndLength);
p += (((dataEndLength + 3) & (~3))/4); // Advance p, insuring 4 byte boundary
}
else
{
return 0;
}
// Serialzed everything successfully
return 1;
}
uint32_t
Buffer::Deserialize (const uint8_t *buffer, uint32_t size)
{
NS_LOG_FUNCTION (this << &buffer << size);
const uint32_t* p = reinterpret_cast<const uint32_t *> (buffer);
uint32_t sizeCheck = size-4;
NS_ASSERT (sizeCheck >= 4);
uint32_t zeroDataLength = *p++;
sizeCheck -= 4;
// Create zero bytes
Initialize (zeroDataLength);
// Add start data
NS_ASSERT (sizeCheck >= 4);
uint32_t dataStartLength = *p++;
sizeCheck -= 4;
AddAtStart (dataStartLength);
NS_ASSERT (sizeCheck >= dataStartLength);
Begin ().Write (reinterpret_cast<uint8_t *> (const_cast<uint32_t *> (p)), dataStartLength);
p += (((dataStartLength+3)&(~3))/4); // Advance p, insuring 4 byte boundary
sizeCheck -= ((dataStartLength+3)&(~3));
// Add end data
NS_ASSERT (sizeCheck >= 4);
uint32_t dataEndLength = *p++;
sizeCheck -= 4;
AddAtEnd (dataEndLength);
NS_ASSERT (sizeCheck >= dataEndLength);
Buffer::Iterator tmp = End ();
tmp.Prev (dataEndLength);
tmp.Write (reinterpret_cast<uint8_t *> (const_cast<uint32_t *> (p)), dataEndLength);
p += (((dataEndLength+3)&(~3))/4); // Advance p, insuring 4 byte boundary
sizeCheck -= ((dataEndLength+3)&(~3));
NS_ASSERT (sizeCheck == 0);
// return zero if buffer did not
// contain a complete message
return (sizeCheck != 0) ? 0 : 1;
}
void
Buffer::TransformIntoRealBuffer (void) const
{
NS_LOG_FUNCTION (this);
NS_ASSERT (CheckInternalState ());
Buffer tmp = CreateFullCopy ();
*const_cast<Buffer *> (this) = tmp;
NS_ASSERT (CheckInternalState ());
}
uint8_t const*
Buffer::PeekData (void) const
{
NS_LOG_FUNCTION (this);
NS_ASSERT (CheckInternalState ());
TransformIntoRealBuffer ();
NS_ASSERT (CheckInternalState ());
return m_data->m_data + m_start;
}
void
Buffer::CopyData (std::ostream *os, uint32_t size) const
{
NS_LOG_FUNCTION (this << &os << size);
if (size > 0)
{
uint32_t tmpsize = std::min (m_zeroAreaStart-m_start, size);
os->write ((const char*)(m_data->m_data + m_start), tmpsize);
if (size > tmpsize)
{
size -= m_zeroAreaStart-m_start;
tmpsize = std::min (m_zeroAreaEnd - m_zeroAreaStart, size);
uint32_t left = tmpsize;
while (left > 0)
{
uint32_t toWrite = std::min (left, g_zeroes.size);
os->write (g_zeroes.buffer, toWrite);
left -= toWrite;
}
if (size > tmpsize)
{
size -= tmpsize;
tmpsize = std::min (m_end - m_zeroAreaEnd, size);
os->write ((const char*)(m_data->m_data + m_zeroAreaStart), tmpsize);
}
}
}
}
uint32_t
Buffer::CopyData (uint8_t *buffer, uint32_t size) const
{
NS_LOG_FUNCTION (this << &buffer << size);
uint32_t originalSize = size;
if (size > 0)
{
uint32_t tmpsize = std::min (m_zeroAreaStart-m_start, size);
memcpy (buffer, (const char*)(m_data->m_data + m_start), tmpsize);
buffer += tmpsize;
size -= tmpsize;
if (size > 0)
{
tmpsize = std::min (m_zeroAreaEnd - m_zeroAreaStart, size);
uint32_t left = tmpsize;
while (left > 0)
{
uint32_t toWrite = std::min (left, g_zeroes.size);
memcpy (buffer, g_zeroes.buffer, toWrite);
left -= toWrite;
buffer += toWrite;
}
size -= tmpsize;
if (size > 0)
{
tmpsize = std::min (m_end - m_zeroAreaEnd, size);
memcpy (buffer, (const char*)(m_data->m_data + m_zeroAreaStart), tmpsize);
size -= tmpsize;
}
}
}
return originalSize - size;
}
/******************************************************
* The buffer iterator below.
******************************************************/
uint32_t
Buffer::Iterator::GetDistanceFrom (Iterator const &o) const
{
NS_LOG_FUNCTION (this << &o);
NS_ASSERT (m_data == o.m_data);
int32_t diff = m_current - o.m_current;
if (diff < 0)
{
return -diff;
}
else
{
return diff;
}
}
bool
Buffer::Iterator::IsEnd (void) const
{
NS_LOG_FUNCTION (this);
return m_current == m_dataEnd;
}
bool
Buffer::Iterator::IsStart (void) const
{
NS_LOG_FUNCTION (this);
return m_current == m_dataStart;
}
bool
Buffer::Iterator::CheckNoZero (uint32_t start, uint32_t end) const
{
NS_LOG_FUNCTION (this << &start << &end);
for (uint32_t i = start; i < end; i++)
{
if (!Check (i))
{
return false;
}
}
return true;
}
bool
Buffer::Iterator::Check (uint32_t i) const
{
NS_LOG_FUNCTION (this << &i);
return i >= m_dataStart &&
!(i >= m_zeroStart && i < m_zeroEnd) &&
i <= m_dataEnd;
}
void
Buffer::Iterator::Write (Iterator start, Iterator end)
{
NS_LOG_FUNCTION (this << &start << &end);
NS_ASSERT (start.m_data == end.m_data);
NS_ASSERT (start.m_current <= end.m_current);
NS_ASSERT (start.m_zeroStart == end.m_zeroStart);
NS_ASSERT (start.m_zeroEnd == end.m_zeroEnd);
NS_ASSERT (m_data != start.m_data);
uint32_t size = end.m_current - start.m_current;
NS_ASSERT_MSG (CheckNoZero (m_current, m_current + size),
GetWriteErrorMessage ());
if (start.m_current <= start.m_zeroStart)
{
uint32_t toCopy = std::min (size, start.m_zeroStart - start.m_current);
memcpy (&m_data[m_current], &start.m_data[start.m_current], toCopy);
start.m_current += toCopy;
m_current += toCopy;
size -= toCopy;
}
if (start.m_current <= start.m_zeroEnd)
{
uint32_t toCopy = std::min (size, start.m_zeroEnd - start.m_current);
memset (&m_data[m_current], 0, toCopy);
start.m_current += toCopy;
m_current += toCopy;
size -= toCopy;
}
uint32_t toCopy = std::min (size, start.m_dataEnd - start.m_current);
uint8_t *from = &start.m_data[start.m_current - (start.m_zeroEnd-start.m_zeroStart)];
uint8_t *to = &m_data[m_current];
memcpy (to, from, toCopy);
m_current += toCopy;
}
void
Buffer::Iterator::WriteU16 (uint16_t data)
{
NS_LOG_FUNCTION (this << data);
WriteU8 (data & 0xff);
data >>= 8;
WriteU8 (data & 0xff);
}
void
Buffer::Iterator::WriteU32 (uint32_t data)
{
NS_LOG_FUNCTION (this << data);
WriteU8 (data & 0xff);
data >>= 8;
WriteU8 (data & 0xff);
data >>= 8;
WriteU8 (data & 0xff);
data >>= 8;
WriteU8 (data & 0xff);
}
void
Buffer::Iterator::WriteU64 (uint64_t data)
{
NS_LOG_FUNCTION (this << data);
WriteU8 (data & 0xff);
data >>= 8;
WriteU8 (data & 0xff);
data >>= 8;
WriteU8 (data & 0xff);
data >>= 8;
WriteU8 (data & 0xff);
data >>= 8;
WriteU8 (data & 0xff);
data >>= 8;
WriteU8 (data & 0xff);
data >>= 8;
WriteU8 (data & 0xff);
data >>= 8;
WriteU8 (data & 0xff);
}
void
Buffer::Iterator::WriteHtolsbU16 (uint16_t data)
{
NS_LOG_FUNCTION (this << data);
WriteU8 ((data >> 0) & 0xff);
WriteU8 ((data >> 8) & 0xff);
}
void
Buffer::Iterator::WriteHtolsbU32 (uint32_t data)
{
NS_LOG_FUNCTION (this << data);
WriteU8 ((data >> 0) & 0xff);
WriteU8 ((data >> 8) & 0xff);
WriteU8 ((data >> 16) & 0xff);
WriteU8 ((data >> 24) & 0xff);
}
void
Buffer::Iterator::WriteHtolsbU64 (uint64_t data)
{
NS_LOG_FUNCTION (this << data);
WriteU8 ((data >> 0) & 0xff);
WriteU8 ((data >> 8) & 0xff);
WriteU8 ((data >> 16) & 0xff);
WriteU8 ((data >> 24) & 0xff);
WriteU8 ((data >> 32) & 0xff);
WriteU8 ((data >> 40) & 0xff);
WriteU8 ((data >> 48) & 0xff);
WriteU8 ((data >> 56) & 0xff);
}
void
Buffer::Iterator::WriteHtonU64 (uint64_t data)
{
NS_LOG_FUNCTION (this << data);
WriteU8 ((data >> 56) & 0xff);
WriteU8 ((data >> 48) & 0xff);
WriteU8 ((data >> 40) & 0xff);
WriteU8 ((data >> 32) & 0xff);
WriteU8 ((data >> 24) & 0xff);
WriteU8 ((data >> 16) & 0xff);
WriteU8 ((data >> 8) & 0xff);
WriteU8 ((data >> 0) & 0xff);
}
void
Buffer::Iterator::Write (uint8_t const*buffer, uint32_t size)
{
NS_LOG_FUNCTION (this << &buffer << size);
NS_ASSERT_MSG (CheckNoZero (m_current, size),
GetWriteErrorMessage ());
uint8_t *to;
if (m_current <= m_zeroStart)
{
to = &m_data[m_current];
}
else
{
to = &m_data[m_current - (m_zeroEnd - m_zeroStart)];
}
memcpy (to, buffer, size);
m_current += size;
}
uint32_t
Buffer::Iterator::ReadU32 (void)
{
NS_LOG_FUNCTION (this);
uint8_t byte0 = ReadU8 ();
uint8_t byte1 = ReadU8 ();
uint8_t byte2 = ReadU8 ();
uint8_t byte3 = ReadU8 ();
uint32_t data = byte3;
data <<= 8;
data |= byte2;
data <<= 8;
data |= byte1;
data <<= 8;
data |= byte0;
return data;
}
uint64_t
Buffer::Iterator::ReadU64 (void)
{
NS_LOG_FUNCTION (this);
uint8_t byte0 = ReadU8 ();
uint8_t byte1 = ReadU8 ();
uint8_t byte2 = ReadU8 ();
uint8_t byte3 = ReadU8 ();
uint8_t byte4 = ReadU8 ();
uint8_t byte5 = ReadU8 ();
uint8_t byte6 = ReadU8 ();
uint8_t byte7 = ReadU8 ();
uint64_t data = byte7;
data <<= 8;
data |= byte6;
data <<= 8;
data |= byte5;
data <<= 8;
data |= byte4;
data <<= 8;
data |= byte3;
data <<= 8;
data |= byte2;
data <<= 8;
data |= byte1;
data <<= 8;
data |= byte0;
return data;
}
uint16_t
Buffer::Iterator::SlowReadNtohU16 (void)
{
NS_LOG_FUNCTION (this);
uint16_t retval = 0;
retval |= ReadU8 ();
retval <<= 8;
retval |= ReadU8 ();
return retval;
}
uint32_t
Buffer::Iterator::SlowReadNtohU32 (void)
{
NS_LOG_FUNCTION (this);
uint32_t retval = 0;
retval |= ReadU8 ();
retval <<= 8;
retval |= ReadU8 ();
retval <<= 8;
retval |= ReadU8 ();
retval <<= 8;
retval |= ReadU8 ();
return retval;
}
uint64_t
Buffer::Iterator::ReadNtohU64 (void)
{
NS_LOG_FUNCTION (this);
uint64_t retval = 0;
retval |= ReadU8 ();
retval <<= 8;
retval |= ReadU8 ();
retval <<= 8;
retval |= ReadU8 ();
retval <<= 8;
retval |= ReadU8 ();
retval <<= 8;
retval |= ReadU8 ();
retval <<= 8;
retval |= ReadU8 ();
retval <<= 8;
retval |= ReadU8 ();
retval <<= 8;
retval |= ReadU8 ();
return retval;
}
uint16_t
Buffer::Iterator::ReadLsbtohU16 (void)
{
NS_LOG_FUNCTION (this);
uint8_t byte0 = ReadU8 ();
uint8_t byte1 = ReadU8 ();
uint16_t data = byte1;
data <<= 8;
data |= byte0;
return data;
}
uint32_t
Buffer::Iterator::ReadLsbtohU32 (void)
{
NS_LOG_FUNCTION (this);
uint8_t byte0 = ReadU8 ();
uint8_t byte1 = ReadU8 ();
uint8_t byte2 = ReadU8 ();
uint8_t byte3 = ReadU8 ();
uint32_t data = byte3;
data <<= 8;
data |= byte2;
data <<= 8;
data |= byte1;
data <<= 8;
data |= byte0;
return data;
}
uint64_t
Buffer::Iterator::ReadLsbtohU64 (void)
{
NS_LOG_FUNCTION (this);
uint8_t byte0 = ReadU8 ();
uint8_t byte1 = ReadU8 ();
uint8_t byte2 = ReadU8 ();
uint8_t byte3 = ReadU8 ();
uint8_t byte4 = ReadU8 ();
uint8_t byte5 = ReadU8 ();
uint8_t byte6 = ReadU8 ();
uint8_t byte7 = ReadU8 ();
uint64_t data = byte7;
data <<= 8;
data |= byte6;
data <<= 8;
data |= byte5;
data <<= 8;
data |= byte4;
data <<= 8;
data |= byte3;
data <<= 8;
data |= byte2;
data <<= 8;
data |= byte1;
data <<= 8;
data |= byte0;
return data;
}
void
Buffer::Iterator::Read (uint8_t *buffer, uint32_t size)
{
NS_LOG_FUNCTION (this << &buffer << size);
for (uint32_t i = 0; i < size; i++)
{
buffer[i] = ReadU8 ();
}
}
uint16_t
Buffer::Iterator::CalculateIpChecksum (uint16_t size)
{
NS_LOG_FUNCTION (this << size);
return CalculateIpChecksum (size, 0);
}
uint16_t
Buffer::Iterator::CalculateIpChecksum (uint16_t size, uint32_t initialChecksum)
{
NS_LOG_FUNCTION (this << size << initialChecksum);
/* see RFC 1071 to understand this code. */
uint32_t sum = initialChecksum;
for (int j = 0; j < size/2; j++)
sum += ReadU16 ();
if (size & 1)
sum += ReadU8 ();
while (sum >> 16)
sum = (sum & 0xffff) + (sum >> 16);
return ~sum;
}
uint32_t
Buffer::Iterator::GetSize (void) const
{
NS_LOG_FUNCTION (this);
return m_dataEnd - m_dataStart;
}
std::string
Buffer::Iterator::GetReadErrorMessage (void) const
{
NS_LOG_FUNCTION (this);
std::string str = "You have attempted to read beyond the bounds of the "
"available buffer space. This usually indicates that a "
"Header::Deserialize or Trailer::Deserialize method "
"is trying to read data which was not written by "
"a Header::Serialize or Trailer::Serialize method. "
"In short: check the code of your Serialize and Deserialize "
"methods.";
return str;
}
std::string
Buffer::Iterator::GetWriteErrorMessage (void) const
{
NS_LOG_FUNCTION (this);
std::string str;
if (m_current < m_dataStart)
{
str = "You have attempted to write before the start of the available "
"buffer space. This usually indicates that Trailer::GetSerializedSize "
"returned a size which is too small compared to what Trailer::Serialize "
"is actually using.";
}
else if (m_current >= m_dataEnd)
{
str = "You have attempted to write after the end of the available "
"buffer space. This usually indicates that Header::GetSerializedSize "
"returned a size which is too small compared to what Header::Serialize "
"is actually using.";
}
else
{
NS_ASSERT (m_current >= m_zeroStart && m_current < m_zeroEnd);
str = "You have attempted to write inside the payload area of the "
"buffer. This usually indicates that your Serialize method uses more "
"buffer space than what your GetSerialized method returned.";
}
return str;
}
} // namespace ns3