NORM-mirror/common/normObject.cpp

2717 lines
91 KiB
C++

#include "normObject.h"
#include "normSession.h"
#include <errno.h>
NormObject::NormObject(NormObject::Type theType,
class NormSession* theSession,
class NormServerNode* theServer,
const NormObjectId& objectId)
: type(theType), session(theSession), server(theServer),
id(objectId), segment_size(0), pending_info(false), repair_info(false),
current_block_id(0), next_segment_id(0),
max_pending_block(0), max_pending_segment(0),
info(NULL), info_len(0), accepted(false)
{
}
NormObject::~NormObject()
{
/*if (server)
server->DeleteObject(true);
else
session->DeleteTxObject(true);*/
Close();
if (info)
{
delete info;
info = NULL;
}
}
// This is mainly used for debug messages
NormNodeId NormObject::LocalNodeId() const
{
return session->LocalNodeId();
}
bool NormObject::Open(const NormObjectSize& objectSize,
const char* infoPtr,
UINT16 infoLen)
{
// Note "objectSize" represents actual total object size for
// DATA or FILE objects, buffer size for STREAM objects
// In either case, we need our sliding bit masks to be of
// appropriate size.
UINT16 segmentSize, numData, numParity;
if (server)
{
segmentSize = server->SegmentSize();
numData = server->BlockSize(); // max source symbols per FEC block
numParity = server->NumParity(); // max parity symbols per FEC block
if (infoLen > 0)
{
pending_info = true;
info_len = 0;
if (!(info = new char[segmentSize]))
{
DMSG(0, "NormObject::Open() info allocation error\n");
return false;
}
}
}
else
{
segmentSize = session->ServerSegmentSize();
numData = session->ServerBlockSize(); // max source symbols per FEC block
numParity = session->ServerNumParity(); // max parity symbols per FEC block
if (infoPtr)
{
if (info) delete []info;
if (infoLen > segmentSize)
{
DMSG(0, "NormObject::Open() info too big error\n");
info_len = 0;
return false;
}
if (!(info = new char[infoLen]))
{
DMSG(0, "NormObject::Open() info allocation error\n");
info_len = 0;
return false;
}
memcpy(info, infoPtr, infoLen);
info_len = infoLen;
pending_info = true;
}
}
// Compute number of segments and coding blocks for the object
// (Note NormObjectSize divide operator always rounds _up_)
NormObjectSize numSegments = objectSize / NormObjectSize(segmentSize);
NormObjectSize numBlocks = numSegments / NormObjectSize(numData);
ASSERT(0 == numBlocks.MSB());
if (!block_buffer.Init(numBlocks.LSB()))
{
DMSG(0, "NormObject::Open() init block_buffer error\n");
Close();
return false;
}
// Init pending_mask (everything pending)
if (!pending_mask.Init(numBlocks.LSB(), 0xffffffff))
{
DMSG(0, "NormObject::Open() init pending_mask error\n");
Close();
return false;
}
pending_mask.Clear();
pending_mask.SetBits(0, numBlocks.LSB());
// Init repair_mask
if (!repair_mask.Init(numBlocks.LSB(), 0xffffffff))
{
DMSG(0, "NormObject::Open() init pending_mask error\n");
Close();
return false;
}
repair_mask.Clear();
if (STREAM == type)
{
small_block_size = large_block_size = numData;
small_block_count = large_block_count = numBlocks.LSB();
final_segment_size = segmentSize;
NormStreamObject* stream = static_cast<NormStreamObject*>(this);
stream->StreamResync(numBlocks.LSB());
}
else
{
// Compute FEC block structure per NORM Protocol Spec Section 5.1.1
// (Note NormObjectSize divide operator always rounds _up_)
NormObjectSize largeBlockSize = numSegments / numBlocks;
ASSERT(0 == largeBlockSize.MSB());
large_block_size = largeBlockSize.LSB();
if (numSegments == (numBlocks*largeBlockSize))
{
small_block_size = large_block_size;
small_block_count = numBlocks.LSB();
large_block_count = 0;
}
else
{
small_block_size = large_block_size - 1;
NormObjectSize largeBlockCount = numSegments - numBlocks*small_block_size;
ASSERT(0 == largeBlockCount.MSB());
large_block_count = largeBlockCount.LSB();
NormObjectSize smallBlockCount = numBlocks - largeBlockCount;
ASSERT(0 == smallBlockCount.MSB());
small_block_count = smallBlockCount.LSB();
}
// not used for STREAM objects
final_block_id = large_block_count + small_block_count - 1;
NormObjectSize finalSegmentSize =
objectSize - (numSegments - NormObjectSize((UINT32)1))*segmentSize;
ASSERT(0 == finalSegmentSize.MSB());
final_segment_size = finalSegmentSize.LSB();
}
object_size = objectSize;
segment_size = segmentSize;
ndata = numData;
nparity = numParity;
current_block_id = 0;
next_segment_id = 0;
max_pending_block = 0;
max_pending_segment = 0;
return true;
} // end NormObject::Open()
void NormObject::Close()
{
NormBlock* block;
while ((block = block_buffer.Find(block_buffer.RangeLo())))
{
block_buffer.Remove(block);
if (server)
server->PutFreeBlock(block);
else
session->ServerPutFreeBlock(block);
}
repair_mask.Destroy();
pending_mask.Destroy();
block_buffer.Destroy();
segment_size = 0;
} // end NormObject::Close();
bool NormObject::HandleInfoRequest()
{
// (TBD) immediately make info pending?
bool increasedRepair = false;
if (info)
{
if (!repair_info)
{
repair_info = true;
increasedRepair = true;
}
}
return increasedRepair;
} // end NormObject::HandleInfoRequest()
bool NormObject::HandleBlockRequest(NormBlockId nextId, NormBlockId lastId)
{
DMSG(6, "NormObject::HandleBlockRequest() node>%lu blk>%lu -> blk>%lu\n",
LocalNodeId(), (UINT32)nextId, (UINT32)lastId);
bool increasedRepair = false;
lastId++;
while (nextId != lastId)
{
if (!repair_mask.Test(nextId))
{
// (TBD) these tests can probably go away if everything else is done right
if (!pending_mask.CanSet(nextId))
DMSG(0, "NormObject::HandleBlockRequest() pending_mask.CanSet(%lu) error\n",
(UINT32)nextId);
if (!repair_mask.Set(nextId))
DMSG(0, "NormObject::HandleBlockRequest() repair_mask.Set(%lu) error\n",
(UINT32)nextId);
increasedRepair = true;
}
nextId++;
}
return increasedRepair;
} // end NormObject::HandleBlockRequest();
bool NormObject::TxReset(NormBlockId firstBlock)
{
bool increasedRepair = false;
if (!pending_info && HaveInfo())
{
increasedRepair = true;
pending_info = true;
}
repair_info = false;
repair_mask.Reset((UINT32)firstBlock);
repair_mask.Xor(pending_mask);
if (repair_mask.IsSet())
{
increasedRepair = true;
pending_mask.Reset((UINT32)firstBlock);
}
repair_mask.Clear();
NormBlockBuffer::Iterator iterator(block_buffer);
NormBlock* block;
while ((block = iterator.GetNextBlock()))
{
NormBlockId blockId = block->Id();
if (blockId >= firstBlock)
{
increasedRepair |= block->TxReset(GetBlockSize(blockId),
nparity,
session->ServerAutoParity(),
segment_size);
}
}
return increasedRepair;
} // end NormObject::TxReset()
bool NormObject::TxResetBlocks(NormBlockId nextId, NormBlockId lastId)
{
bool increasedRepair = false;
UINT16 autoParity = session->ServerAutoParity();
lastId++;
while (nextId != lastId)
{
if (!pending_mask.Test(nextId))
{
pending_mask.Set(nextId);
increasedRepair = true;
}
NormBlock* block = block_buffer.Find(nextId);
if (block)
increasedRepair |= block->TxReset(GetBlockSize(block->Id()), nparity, autoParity, segment_size);
nextId++;
}
return increasedRepair;
} // end NormObject::TxResetBlocks()
bool NormObject::ActivateRepairs()
{
bool repairsActivated = false;
// Activate repair of info if applicable (TBD - how to flag info message as repair???)
if (repair_info)
{
pending_info = true;
repair_info = false;
repairsActivated = true;
}
// Activate any complete block repairs
NormBlockId nextId;
if (GetFirstRepair(nextId))
{
NormBlockId lastId;
ASSERT(GetLastRepair(lastId));
DMSG(6, "NormObject::ActivateRepairs() node>%lu obj>%hu activating blk>%lu->%lu repairs\n",
LocalNodeId(), (UINT16)id, (UINT32)nextId, (UINT32)lastId);
repairsActivated = true;
UINT16 autoParity = session->ServerAutoParity();
do
{
NormBlock* block = block_buffer.Find(nextId);
if (block) block->TxReset(GetBlockSize(nextId), nparity, autoParity, segment_size);
// (TBD) This check can be eventually eliminated if everything else is done right
if (!pending_mask.Set(nextId))
DMSG(0, "NormObject::ActivateRepairs() pending_mask.Set(%lu) error!\n", (UINT32)nextId);
nextId++;
} while (GetNextRepair(nextId));
repair_mask.Clear();
}
// Activate partial block (segment) repairs
NormBlockBuffer::Iterator iterator(block_buffer);
NormBlock* block;
while ((block = iterator.GetNextBlock()))
{
if (block->ActivateRepairs(nparity))
{
repairsActivated = true;
DMSG(6, "NormObject::ActivateRepairs() node>%lu obj>%hu activated blk>%lu segment repairs ...\n",
LocalNodeId(), (UINT16)id, (UINT32)block->Id());
// (TBD) This check can be eventually eliminated if everything else is done right
if (!pending_mask.Set(block->Id()))
DMSG(0, "NormObject::ActivateRepairs() pending_mask.Set(%lu) error!\n", (UINT32)block->Id());
}
}
return repairsActivated;
} // end NormObject::ActivateRepairs()
// called by servers only
bool NormObject::AppendRepairAdv(NormCmdRepairAdvMsg& cmd)
{
// Determine range of blocks possibly pending repair
NormBlockId nextId;
GetFirstRepair(nextId);
NormBlockId endId;
GetLastRepair(endId);
if (block_buffer.IsEmpty())
{
if (repair_mask.IsSet()) endId++;
}
else
{
NormBlockId lo = block_buffer.RangeLo();
NormBlockId hi = block_buffer.RangeHi();
if (repair_mask.IsSet())
{
nextId = (lo < nextId) ? lo : nextId;
endId = (hi > endId) ? hi : endId;
}
else
{
nextId = lo;
endId = hi;
}
endId++;
}
// Instantiate a repair request for BLOCK level repairs
NormRepairRequest req;
req.SetFlag(NormRepairRequest::BLOCK);
if (repair_info) req.SetFlag(NormRepairRequest::INFO);
NormRepairRequest::Form prevForm = NormRepairRequest::INVALID;
// Iterate through the range of blocks possibly pending repair
NormBlockId firstId;
UINT32 blockCount = 0;
while (nextId < endId)
{
NormBlockId currentId = nextId;
nextId++;
//DMSG(0, "NormObject::AppendRepairAdv() testing block:%lu nextId:%lu endId:%lu\n",
// (UINT32)currentId, (UINT32)nextId, (UINT32)endId);
bool repairEntireBlock = repair_mask.Test(currentId);
if (repairEntireBlock)
{
if (!blockCount) firstId = currentId;
blockCount++;
}
// Check for break in continuity or end
if (blockCount && (!repairEntireBlock || (nextId >= endId)))
{
NormRepairRequest::Form form;
switch (blockCount)
{
case 0:
form = NormRepairRequest::INVALID;
break;
case 1:
case 2:
form = NormRepairRequest::ITEMS;
break;
default:
form = NormRepairRequest::RANGES;
break;
}
if (form != prevForm)
{
if (NormRepairRequest::INVALID != prevForm)
cmd.PackRepairRequest(req); // (TBD) error check
cmd.AttachRepairRequest(req, segment_size); // (TBD) error check
req.SetForm(form);
prevForm = form;
}
switch (form)
{
case NormRepairRequest::INVALID:
ASSERT(0); // can't happen
break;
case NormRepairRequest::ITEMS:
req.AppendRepairItem(id, firstId, ndata, 0);
if (2 == blockCount)
req.AppendRepairItem(id, currentId, ndata, 0);
break;
case NormRepairRequest::RANGES:
req.AppendRepairRange(id, firstId, ndata, 0,
id, currentId, ndata, 0);
break;
case NormRepairRequest::ERASURES:
// erasure counts not used
break;
}
blockCount = 0;
}
if (!repairEntireBlock)
{
NormBlock* block = block_buffer.Find(currentId);
if (block && block->IsRepairPending())
{
if (NormRepairRequest::INVALID != prevForm)
{
cmd.PackRepairRequest(req); // (TBD) error check
prevForm = NormRepairRequest::INVALID;
}
block->AppendRepairAdv(cmd, id, repair_info, ndata, segment_size); // (TBD) error check
}
}
} // end while(nextId < endId)
if (NormRepairRequest::INVALID != prevForm)
cmd.PackRepairRequest(req); // (TBD) error check
return true;
} // end NormObject::AppendRepairAdv()
// Called by server only
bool NormObject::IsRepairPending() const
{
ASSERT(!server);
if (repair_info) return true;
if (repair_mask.IsSet()) return true;
NormBlockBuffer::Iterator iterator(block_buffer);
NormBlock* block;
while ((block = iterator.GetNextBlock()))
{
if (block->IsRepairPending()) return true;
}
return false;
} // end NormObject::IsRepairPending()
bool NormObject::IsPending(bool flush) const
{
if (pending_info) return true;
if (flush)
{
return pending_mask.IsSet();
}
else
{
NormBlockId firstId;
if (GetFirstPending(firstId))
{
if (firstId < max_pending_block)
{
return true;
}
else if (firstId > max_pending_block)
{
return false;
}
else
{
if (max_pending_segment > 0)
{
NormBlock* block = block_buffer.Find(max_pending_block);
if (block)
{
ASSERT(block->IsPending());
NormSegmentId firstPending = 0;
block->GetFirstPending(firstPending);
if (firstPending < max_pending_segment)
return true;
else
return false;
}
else
{
return true;
}
}
else
{
return false;
}
}
}
else
{
return false;
}
}
} // end NormObject::IsPending()
bool NormObject::ClientRepairCheck(CheckLevel level,
NormBlockId blockId,
NormSegmentId segmentId,
bool timerActive,
bool holdoffPhase)
{
// (TBD) make sure it's OK for "max_pending_segment"
// and "next_segment_id" to be > blockSize
switch (level)
{
case THRU_INFO:
break;
case TO_BLOCK:
if (blockId >= max_pending_block)
{
max_pending_block = blockId;
max_pending_segment = 0;
}
break;
case THRU_SEGMENT:
if (blockId > max_pending_block)
{
max_pending_block = blockId;
max_pending_segment = segmentId + 1;
}
else if (blockId == max_pending_block)
{
if (segmentId >= max_pending_segment)
max_pending_segment = segmentId + 1;
}
break;
case THRU_BLOCK:
if (blockId > max_pending_block)
{
max_pending_block = blockId;
max_pending_segment = GetBlockSize(blockId);
}
break;
case THRU_OBJECT:
if (!IsStream())
max_pending_block = final_block_id;
else if (blockId > max_pending_block)
max_pending_block = blockId;
max_pending_segment = GetBlockSize(max_pending_block);
break;
default:
break;
} // end switch (level)
if (timerActive)
{
if (holdoffPhase) return false;
switch (level)
{
case THRU_INFO:
current_block_id = 0;
next_segment_id = 0;
break;
case TO_BLOCK:
if (blockId < current_block_id)
{
current_block_id = blockId;
next_segment_id = 0;
}
break;
case THRU_SEGMENT:
if (blockId < current_block_id)
{
current_block_id = blockId;
next_segment_id = segmentId + 1;
}
else if (blockId == current_block_id)
{
if (segmentId < next_segment_id)
next_segment_id = segmentId + 1;
}
break;
case THRU_BLOCK:
if (blockId < current_block_id)
{
current_block_id = blockId;
next_segment_id = GetBlockSize(blockId);
}
break;
default:
break;
}
return false; // repair_timer already running
}
bool needRepair = false;
if (pending_info)
{
repair_info = false;
needRepair = true;
}
if ((level > THRU_INFO) && pending_mask.IsSet())
{
if (repair_mask.IsSet()) repair_mask.Clear();
NormBlockId nextId;
if (GetFirstPending(nextId))
{
NormBlockId lastId;
GetLastPending(lastId);
if ((level < THRU_OBJECT) && (blockId < lastId)) lastId = blockId;
if (level > TO_BLOCK) lastId++;
while (nextId < lastId)
{
if (nextId > lastId) break;
NormBlock* block = block_buffer.Find(nextId);
if (block)
{
if ((nextId == blockId) && (THRU_SEGMENT == level))
{
NormSymbolId firstPending = 0;
if (!block->GetFirstPending(firstPending)) ASSERT(0);
if (firstPending <= segmentId)
{
block->ClearRepairs();
needRepair = true;
}
}
else
{
block->ClearRepairs();
needRepair = true;
}
}
else
{
needRepair = true;
}
nextId++;
if (!GetNextPending(nextId)) break;
} // end while (nextId < lastId)
}
}
switch (level)
{
case THRU_INFO:
current_block_id = 0;
next_segment_id = 0;
break;
case TO_BLOCK:
current_block_id = blockId;
next_segment_id = 0;
break;
case THRU_SEGMENT:
current_block_id = blockId;
next_segment_id = segmentId + 1;
break;
case THRU_BLOCK:
current_block_id = blockId;
next_segment_id = GetBlockSize(blockId);
break;
case THRU_OBJECT:
if (IsStream())
current_block_id = max_pending_block;
else
current_block_id = final_block_id;
next_segment_id = GetBlockSize(current_block_id);
default:
break;
}
return needRepair;
} // end NormObject::ClientRepairCheck()
// Note this clears "repair_mask" state (called on client repair_timer timeout)
bool NormObject::IsRepairPending(bool flush)
{
ASSERT(server);
if (pending_info && !repair_info) return true;
// Calculate repair_mask = pending_mask - repair_mask
repair_mask.XCopy(pending_mask);
NormBlockId nextId;
if (GetFirstRepair(nextId))
{
do
{
if (!flush && (nextId > current_block_id)) break;
NormBlock* block = block_buffer.Find(nextId);
if (block)
{
bool isPending;
UINT16 numData = GetBlockSize(nextId);
if (flush || (nextId < current_block_id))
{
isPending = block->IsRepairPending(numData, nparity);
}
else
{
if (next_segment_id < numData)
isPending = block->IsRepairPending(next_segment_id, 0);
else
isPending = block->IsRepairPending(numData, nparity);
}
if (isPending) return true;
}
else
{
return true; // We need the whole thing
}
nextId++;
} while (GetNextRepair(nextId));
}
return false;
} // end NormObject::IsRepairPending()
bool NormObject::AppendRepairRequest(NormNackMsg& nack,
bool flush)
{
// If !flush, we request only up _to_ max_pending_block::max_pending_segment.
NormRepairRequest req;
NormRepairRequest::Form prevForm = NormRepairRequest::INVALID;
NormBlockId nextId;
bool iterating = GetFirstPending(nextId);
if (iterating)
{
iterating = iterating && (flush || (nextId <= max_pending_block));
NormBlockId prevId = nextId;
UINT32 consecutiveCount = 0;
while (iterating || (0 != consecutiveCount))
{
NormBlockId lastId;
ASSERT(GetLastPending(lastId));
DMSG(6, "NormObject::AppendRepairRequest() node>%lu obj>%hu, blk>%lu->%lu (maxPending:%lu)\n",
LocalNodeId(), (UINT16)id,
(UINT32)nextId, (UINT32)lastId, (UINT32)max_pending_block);
bool appendRequest = false;
NormBlock* block = iterating ? block_buffer.Find(nextId) : NULL;
if (block)
appendRequest = true;
else if (iterating && ((UINT32)(nextId - prevId) == consecutiveCount))
{
consecutiveCount++;
}
else
appendRequest = true;
if (appendRequest)
{
NormRepairRequest::Form nextForm;
switch(consecutiveCount)
{
case 0:
nextForm = NormRepairRequest::INVALID;
break;
case 1:
case 2:
nextForm = NormRepairRequest::ITEMS;
break;
default:
nextForm = NormRepairRequest::RANGES;
break;
} // end switch(reqCount)
if (prevForm != nextForm)
{
if (NormRepairRequest::INVALID != prevForm)
nack.PackRepairRequest(req); // (TBD) error check
if (NormRepairRequest::INVALID != nextForm)
{
nack.AttachRepairRequest(req, segment_size);
req.SetForm(nextForm);
req.ResetFlags();
req.SetFlag(NormRepairRequest::BLOCK);
if (pending_info) req.SetFlag(NormRepairRequest::INFO);
}
prevForm = nextForm;
}
if (NormRepairRequest::INVALID != nextForm)
DMSG(6, "NormObject::AppendRepairRequest() BLOCK request\n");
switch (nextForm)
{
case NormRepairRequest::ITEMS:
req.AppendRepairItem(id, prevId, GetBlockSize(prevId), 0); // (TBD) error check
if (2 == consecutiveCount)
{
prevId++;
req.AppendRepairItem(id, prevId, GetBlockSize(prevId), 0); // (TBD) error check
}
break;
case NormRepairRequest::RANGES:
{
NormBlockId lastId = prevId+consecutiveCount-1;
req.AppendRepairRange(id, prevId, GetBlockSize(prevId), 0,
id, lastId, GetBlockSize(lastId), 0); // (TBD) error check
break;
}
default:
break;
} // end switch(nextForm)
if (block)
{
bool blockPending = false;
if (nextId == max_pending_block)
{
NormSymbolId firstPending = 0;
if (!block->GetFirstPending(firstPending)) ASSERT(0);
if (firstPending < max_pending_segment) blockPending = true;
}
else
{
blockPending = true;
}
if (blockPending)
{
UINT16 numData = GetBlockSize(nextId);
if (NormRepairRequest::INVALID != prevForm)
nack.PackRepairRequest(req); // (TBD) error check
if (flush || (nextId != max_pending_block))
{
block->AppendRepairRequest(nack, numData, nparity, id,
pending_info, segment_size); // (TBD) error check
}
else
{
if (max_pending_segment < numData)
block->AppendRepairRequest(nack, max_pending_segment, 0, id,
pending_info, segment_size); // (TBD) error check
else
block->AppendRepairRequest(nack, numData, nparity, id,
pending_info, segment_size); // (TBD) error check
}
}
consecutiveCount = 0;
prevForm = NormRepairRequest::INVALID;
}
else if (iterating)
{
consecutiveCount = 1;
}
else
{
consecutiveCount = 0; // we're all done
}
prevId = nextId;
} // end if (appendRequest)
nextId++;
iterating = GetNextPending(nextId);
//DMSG(0, "got next pending>%lu result:%d\n", (UINT32)nextId, iterating);
iterating = iterating && (flush || (nextId <= max_pending_block));
} // end while (iterating || (0 != consecutiveCount))
//DMSG(0, "bailed ...\n");
}
else
{
// INFO_ONLY repair request
ASSERT(pending_info);
nack.AttachRepairRequest(req, segment_size);
prevForm = NormRepairRequest::ITEMS;
req.SetForm(NormRepairRequest::ITEMS);
req.ResetFlags();
req.SetFlag(NormRepairRequest::INFO);
req.AppendRepairItem(id, 0, 0, 0); // (TBD) error check
} // end if/else (iterating)
if (NormRepairRequest::INVALID != prevForm)
nack.PackRepairRequest(req); // (TBD) error check
return true;
} // end NormObject::AppendRepairRequest()
void NormObject::HandleObjectMessage(const NormObjectMsg& msg,
NormMsg::Type msgType,
NormBlockId blockId,
NormSegmentId segmentId)
{
if (NormMsg::INFO == msgType)
{
if (pending_info)
{
const NormInfoMsg& infoMsg = (const NormInfoMsg&)msg;
info_len = infoMsg.GetInfoLen();
if (info_len > segment_size)
{
info_len = segment_size;
DMSG(0, "NormObject::HandleObjectMessage() node>%lu server>%lu obj>%hu "
"Warning! info too long.\n", LocalNodeId(), server->GetId(), (UINT16)id);
}
memcpy(info, infoMsg.GetInfo(), info_len);
pending_info = false;
session->Notify(NormController::RX_OBJECT_INFO, server, this);
}
else
{
// (TBD) Verify info hasn't changed?
DMSG(6, "NormObject::HandleObjectMessage() node>%lu server>%lu obj>%hu "
"received duplicate info ...\n", LocalNodeId(),
server->GetId(), (UINT16)id);
}
}
else // NORM_MSG_DATA
{
const NormDataMsg& data = (const NormDataMsg&)msg;
// For stream objects, a little extra mgmt is required
if (STREAM == type)
{
NormStreamObject* stream = static_cast<NormStreamObject*>(this);
if (!stream->StreamUpdateStatus(blockId))
{
DMSG(4, "NormObject::HandleObjectMessage() node:%lu server:%lu obj>%hu blk>%lu "
"broken stream ...\n", LocalNodeId(), server->GetId(), (UINT16)id, (UINT32)blockId);
//ASSERT(0);
// ??? Ignore this new packet and try to fix stream ???
//return;
server->IncrementResyncCount();
while (!stream->StreamUpdateStatus(blockId))
{
// Server is too far ahead of me ...
NormBlockId firstId;
if (GetFirstPending(firstId))
{
NormBlock* block = block_buffer.Find(firstId);
if (block)
{
block_buffer.Remove(block);
server->PutFreeBlock(block);
}
pending_mask.Unset(firstId);
}
else
{
stream->StreamResync(blockId);// - NormBlockId(pending_mask.Size()));
}
}
}
}
UINT16 numData = GetBlockSize(blockId);
if (pending_mask.Test(blockId))
{
NormBlock* block = block_buffer.Find(blockId);
if (!block)
{
if (!(block = server->GetFreeBlock(id, blockId)))
{
DMSG(2, "NormObject::HandleObjectMessage() node>%lu server>%lu obj>%hu "
"Warning! no free blocks ...\n", LocalNodeId(), server->GetId(),
(UINT16)id);
return;
}
block->RxInit(blockId, numData, nparity);
block_buffer.Insert(block);
}
if (block->IsPending(segmentId))
{
// 1) Cache segment in block buffer in case its needed for decoding
char* segment = server->GetFreeSegment(id, blockId);
if (!segment)
{
DMSG(2, "NormObject::HandleObjectMessage() node>%lu server>%lu obj>%hu "
"Warning! no free segments ...\n", LocalNodeId(), server->GetId(),
(UINT16)id);
return;
}
UINT16 segmentLength = data.GetPayloadDataLength();
if (segmentLength > segment_size)
{
DMSG(0, "NormObject::HandleObjectMessage() node>%lu server>%lu obj>%hu "
"Error! segment too large ...\n", LocalNodeId(), server->GetId(),
(UINT16)id);
server->PutFreeSegment(segment);
return;
}
UINT16 payloadLength = data.GetPayloadLength();
UINT16 payloadMax = segment_size + NormDataMsg::GetStreamPayloadHeaderLength();
#ifdef SIMULATE
// For simulations, we may need to cap the payloadLength
payloadMax = MIN(payloadMax, SIM_PAYLOAD_MAX);
payloadLength = MIN(payloadLength, SIM_PAYLOAD_MAX);
#endif // SIMULATE
memcpy(segment, data.GetPayload(), payloadLength);
if (payloadLength < payloadMax)
memset(segment+payloadLength, 0, payloadMax-payloadLength);
if (data.FlagIsSet(NormObjectMsg::FLAG_MSG_START))
{
segment[payloadMax] = NormObjectMsg::FLAG_MSG_START;
//DMSG(0, "starting segment payload len>%hu msg_len>%hu\n",
// payloadLength, ntohs(*((UINT16*)(segment+8)))) ;
}
else
segment[payloadMax] = 0;
block->AttachSegment(segmentId, segment);
block->UnsetPending(segmentId);
// 2) Write segment to object (if it's data)
if (segmentId < numData)
{
block->DecrementErasureCount();
if (WriteSegment(blockId, segmentId, segment))
server->IncrementRecvGoodput(segmentLength);
}
else
{
block->IncrementParityCount();
}
// 3) Decode block if ready and return to pool
if (block->ErasureCount() <= block->ParityCount())
{
// Decode (if pending_mask.FirstSet() < numData)
// and write any decoded data segments to object
DMSG(8, "NormObject::HandleObjectMessage() node>%lu server>%lu obj>%hu blk>%lu "
"completed block ...\n", LocalNodeId(), server->GetId(),
(UINT16)id, (UINT32)block->Id());
UINT16 erasureCount = 0;
UINT16 nextErasure = 0;
if (block->GetFirstPending(nextErasure))
{
if (nextErasure < numData)
{
do
{
server->SetErasureLoc(erasureCount++, nextErasure);
if (nextErasure < numData)
{
if (!(segment = server->GetFreeSegment(id, blockId)))
{
DMSG(2, "NormObject::HandleObjectMessage() node>%lu server>%lu obj>%hu "
"Warning! no free segments ...\n", LocalNodeId(), server->GetId(),
(UINT16)id);
// (TBD) Dump the block ...???
return;
}
UINT16 payloadMax = segment_size + NormDataMsg::GetStreamPayloadHeaderLength();
#ifdef SIMULATE
payloadMax = MIN(payloadMax, SIM_PAYLOAD_MAX);
#endif // SIMULATE
memset(segment, 0, payloadMax+1);
block->SetSegment(nextErasure, segment);
}
nextErasure++;
} while (block->GetNextPending(nextErasure));
}
}
if (erasureCount)
{
server->Decode(block->SegmentList(), numData, erasureCount);
for (UINT16 i = 0; i < erasureCount; i++)
{
NormSegmentId sid = server->GetErasureLoc(i);
if (sid < numData)
{
if (WriteSegment(blockId, sid, block->Segment(sid)))
{
// For statistics only (TBD) #ifdef NORM_DEBUG
server->IncrementRecvGoodput(segmentLength);
}
}
else
{
break;
}
}
}
// OK, we're done with this block
pending_mask.Unset(blockId);
block_buffer.Remove(block);
server->PutFreeBlock(block);
}
// Notify application of new data available
// (TBD) this could be improved for stream objects
// so it's not called unnecessarily
session->Notify(NormController::RX_OBJECT_UPDATE, server, this);
}
else
{
DMSG(6, "NormObject::HandleObjectMessage() node>%lu server>%lu obj>%hu "
"received duplicate segment ...\n", LocalNodeId(),
server->GetId(), (UINT16)id);
}
}
else
{
DMSG(6, "NormObject::HandleObjectMessage() node>%lu server>%lu obj>%hu "
"received duplicate block message ...\n", LocalNodeId(),
server->GetId(), (UINT16)id);
} // end if/else pending_mask.Test(blockId)
} // end if/else (NORM_MSG_INFO)
} // end NormObject::HandleObjectMessage()
// Steals non-pending block (oldest first) for server resource management
// (optionally excludes block indicated by blockId)
NormBlock* NormObject::StealNonPendingBlock(bool excludeBlock, NormBlockId excludeId)
{
if (block_buffer.IsEmpty())
{
return NULL;
}
else
{
NormBlockBuffer::Iterator iterator(block_buffer);
NormBlock* block;
while ((block = iterator.GetNextBlock()))
{
NormBlockId bid = block->Id();
if (block->IsTransmitPending() ||
pending_mask.Test(bid) ||
repair_mask.Test(bid) ||
(excludeBlock && (excludeId == bid)))
{
continue;
}
else
{
block_buffer.Remove(block);
return block;
}
}
}
return NULL;
} // end NormObject::StealNonPendingBlock()
// For client resource management, steals newer block resources when
// needing resources for ordinally older blocks.
NormBlock* NormObject::StealNewestBlock(bool excludeBlock, NormBlockId excludeId)
{
if (block_buffer.IsEmpty())
{
return NULL;
}
else
{
NormBlock* block = block_buffer.Find(block_buffer.RangeHi());
if (excludeBlock && (excludeId == block->Id()))
{
return NULL;
}
else
{
block_buffer.Remove(block);
return block;
}
}
} // end NormObject::StealNewestBlock()
// For silent client resource management, steals newer block resources when
// needing resources for ordinally older blocks.
NormBlock* NormObject::StealOldestBlock(bool excludeBlock, NormBlockId excludeId)
{
if (block_buffer.IsEmpty())
{
return NULL;
}
else
{
NormBlock* block = block_buffer.Find(block_buffer.RangeLo());
if (excludeBlock && (excludeId == block->Id()))
{
return NULL;
}
else
{
block_buffer.Remove(block);
return block;
}
}
} // end NormObject::StealOldestBlock()
bool NormObject::NextServerMsg(NormObjectMsg* msg)
{
// Init() the message
if (pending_info)
((NormInfoMsg*)msg)->Init();
else
((NormDataMsg*)msg)->Init();
// General object message flags
msg->ResetFlags();
switch(type)
{
case STREAM:
msg->SetFlag(NormObjectMsg::FLAG_STREAM);
break;
case FILE:
msg->SetFlag(NormObjectMsg::FLAG_FILE);
break;
default:
break;
}
if (info) msg->SetFlag(NormObjectMsg::FLAG_INFO);
msg->SetFecId(129);
msg->SetObjectId(id);
// We currently always apply the FTI extension
NormFtiExtension fti;
msg->AttachExtension(fti);
fti.SetSegmentSize(segment_size);
fti.SetObjectSize(object_size);
fti.SetFecMaxBlockLen(ndata);
fti.SetFecNumParity(nparity);
if (pending_info)
{
// (TBD) set REPAIR_FLAG for retransmitted info
NormInfoMsg* infoMsg = (NormInfoMsg*)msg;
infoMsg->SetInfo(info, info_len);
pending_info = false;
return true;
}
NormBlockId blockId;
if (!GetFirstPending(blockId)) return false;
NormDataMsg* data = (NormDataMsg*)msg;
UINT16 numData = GetBlockSize(blockId);
NormBlock* block = block_buffer.Find(blockId);
if (!block)
{
if (!(block = session->ServerGetFreeBlock(id, blockId)))
{
DMSG(2, "NormObject::NextServerMsg() node>%lu Warning! server resource "
"constrained (no free blocks).\n", LocalNodeId());
return false;
}
// Load block with zero initialized parity segments
UINT16 totalBlockLen = numData + nparity;
for (UINT16 i = numData; i < totalBlockLen; i++)
{
char* s = session->ServerGetFreeSegment(id, blockId);
if (s)
{
UINT16 payloadMax = segment_size + NormDataMsg::GetStreamPayloadHeaderLength();
#ifdef SIMULATE
payloadMax = MIN(payloadMax, SIM_PAYLOAD_MAX);
#endif // SIMULATE
memset(s, 0, payloadMax+1); // extra byte for msg flags
block->AttachSegment(i, s);
}
else
{
DMSG(2, "NormObject::NextServerMsg() node>%lu Warning! server resource "
"constrained (no free segments).\n", LocalNodeId());
session->ServerPutFreeBlock(block);
return false;
}
}
block->TxInit(blockId, numData, session->ServerAutoParity());
if (!block_buffer.Insert(block))
{
ASSERT(STREAM == type);
ASSERT(blockId > block_buffer.RangeLo());
NormBlock* b = block_buffer.Find(block_buffer.RangeLo());
ASSERT(b);
block_buffer.Remove(b);
session->ServerPutFreeBlock(b);
bool success = block_buffer.Insert(block);
ASSERT(success);
}
}
NormSegmentId segmentId = 0;
if (!block->GetFirstPending(segmentId)) ASSERT(0);
// Try to read segment
if (segmentId < numData)
{
// Try to read data segment (Note "ReadSegment" copies in offset/length info also)
char* buffer = data->AccessPayload();
UINT16 payloadLength = ReadSegment(blockId, segmentId, buffer);
if (0 == payloadLength)
{
// (TBD) deal with read error
//(for streams, it currently means the stream is non-pending)
if (!IsStream()) DMSG(0, "NormObject::NextServerMsg() ReadSegment() error\n");
return false;
}
data->SetPayloadLength(payloadLength);
if (IsStream())
{
// Look for FLAG_MSG_START
UINT16 payloadMax = segment_size+NormDataMsg::GetStreamPayloadHeaderLength();
#ifdef SIMULATE
payloadMax = MIN(payloadMax, SIM_PAYLOAD_MAX);
#endif // SIMULATE
if (buffer[payloadMax])
{
data->SetFlag(NormObjectMsg::FLAG_MSG_START);
//DMSG(0, "read start segment len:%hu\n", ntohs(*((UINT16*)(buffer+2))));
//DMSG(0, " message len:%hu\n", ntohs(*((UINT16*)(buffer+8))));
}
else
{
//DMSG(0, "non-start segment read ...\n");
}
}
// Perform incremental FEC encoding as needed
if ((block->ParityReadiness() == segmentId) && nparity)
// (TBD) && incrementalParity == true
{
// (TBD) for non-stream objects, catch alternate "last block/segment len"
// ZERO pad any "runt" segments before encoding
UINT16 payloadMax = segment_size + NormDataMsg::GetStreamPayloadHeaderLength();
#ifdef SIMULATE
payloadMax = MIN(payloadMax, SIM_PAYLOAD_MAX);
#endif // SIMULATE
if (payloadLength < payloadMax)
memset(buffer+payloadLength, 0, payloadMax-payloadLength);
// (TBD) the encode routine could update the block's parity readiness
session->ServerEncode(data->AccessPayload(), block->SegmentList(numData));
block->IncreaseParityReadiness();
}
}
else
{
if (!block->ParityReady(numData))
{
ASSERT(0 == block->ParityReadiness());
CalculateBlockParity(block);
}
ASSERT(block->ParityReady(numData));
char* segment = block->Segment(segmentId);
ASSERT(segment);
UINT16 payloadLength = segment_size;
if (IsStream()) payloadLength += NormDataMsg::GetStreamPayloadHeaderLength();
data->SetPayload(segment, payloadLength);
}
block->UnsetPending(segmentId);
if (block->InRepair())
data->SetFlag(NormObjectMsg::FLAG_REPAIR);
data->SetFecBlockId(blockId);
data->SetFecBlockLen(numData);
data->SetFecSymbolId(segmentId);
if (!block->IsPending())
{
block->ResetParityCount(nparity);
pending_mask.Unset(blockId);
}
// This lets NORM_STREAM objects continue indefinitely
if (IsStream() && !pending_mask.IsSet())
static_cast<NormStreamObject*>(this)->StreamAdvance();
return true;
} // end NormObject::NextServerMsg()
void NormStreamObject::StreamAdvance()
{
NormBlockId nextBlockId = stream_next_id;
// Make sure we won't prevent about any pending repairs
if (repair_mask.CanSet(nextBlockId))
{
if (block_buffer.CanInsert(nextBlockId))
{
if (pending_mask.Set(nextBlockId))
stream_next_id++;
else
DMSG(0, "NormStreamObject::StreamAdvance() error setting stream pending mask (1)\n");
}
else
{
NormBlock* block = block_buffer.Find(block_buffer.RangeLo());
ASSERT(block);
if (!block->IsTransmitPending())
{
// ??? (TBD) Should this block be returned to the pool right now???
if (pending_mask.Set(nextBlockId))
stream_next_id++;
else
DMSG(0, "NormStreamObject::StreamAdvance() error setting stream pending mask (2)\n");
}
else
{
DMSG(4, "NormStreamObject::StreamAdvance() node>%lu Pending segment repairs (blk>%lu) "
"delaying stream advance ...\n", LocalNodeId(), (UINT32)block->Id());
}
}
}
else
{
DMSG(0, "NormStreamObject::StreamAdvance() Pending block repair delaying stream advance ...\n");
}
} // end NormStreamObject::StreamAdvance()
bool NormObject::CalculateBlockParity(NormBlock* block)
{
char buffer[NormMsg::MAX_SIZE];
UINT16 numData = GetBlockSize(block->Id());
for (UINT16 i = 0; i < numData; i++)
{
UINT16 payloadLength = ReadSegment(block->Id(), i, buffer);
if (0 != payloadLength)
{
UINT16 payloadMax = segment_size+NormDataMsg::GetStreamPayloadHeaderLength();
#ifdef SIMULATE
payloadMax = MIN(payloadMax, SIM_PAYLOAD_MAX);
#endif // SIMULATE
if (payloadLength < payloadMax)
memset(buffer+payloadLength, 0, payloadMax-payloadLength);
session->ServerEncode(buffer, block->SegmentList(numData));
}
else
{
return false;
}
}
block->SetParityReadiness(numData);
return true;
} // end NormObject::CalculateBlockParity()
NormBlock* NormObject::ServerRecoverBlock(NormBlockId blockId)
{
NormBlock* block = session->ServerGetFreeBlock(id, blockId);
if (block)
{
UINT16 numData = GetBlockSize(blockId);
// Init block parameters
block->TxRecover(blockId, numData, nparity);
// Fill block with zero initialized parity segments
UINT16 totalBlockLen = numData + nparity;
for (UINT16 i = numData; i < totalBlockLen; i++)
{
char* s = session->ServerGetFreeSegment(id, blockId);
if (s)
{
UINT16 payloadMax = segment_size + NormDataMsg::GetStreamPayloadHeaderLength();
#ifdef SIMULATE
payloadMax = MIN(payloadMax, SIM_PAYLOAD_MAX);
#endif // SIMULATE
memset(s, 0, payloadMax+1); // extra byte for msg flags
block->AttachSegment(i, s);
}
else
{
DMSG(2, "NormObject::ServerRecoverBlock() node>%lu Warning! server resource "
"constrained (no free segments).\n", LocalNodeId());
session->ServerPutFreeBlock(block);
return (NormBlock*)NULL;
}
}
// Attempt to re-generate parity
if (CalculateBlockParity(block))
{
if (!block_buffer.Insert(block))
{
session->ServerPutFreeBlock(block);
DMSG(4, "NormObject::ServerRecoverBlock() node>%lu couldn't buffer recovered block\n");
return NULL;
}
return block;
}
else
{
session->ServerPutFreeBlock(block);
return (NormBlock*)NULL;
}
}
else
{
DMSG(2, "NormObject::ServerRecoverBlock() node>%lu Warning! server resource "
"constrained (no free blocks).\n", LocalNodeId());
return (NormBlock*)NULL;
}
} // end NormObject::ServerRecoverBlock()
/////////////////////////////////////////////////////////////////
//
// NormFileObject Implementation
//
NormFileObject::NormFileObject(class NormSession* theSession,
class NormServerNode* theServer,
const NormObjectId& objectId)
: NormObject(FILE, theSession, theServer, objectId),
large_block_length(0,0), small_block_length(0,0)
{
path[0] = '\0';
}
NormFileObject::~NormFileObject()
{
Close();
}
// Open file
bool NormFileObject::Open(const char* thePath,
const char* infoPtr,
UINT16 infoLen)
{
if (server)
{
// We're receiving this file
if (NormFile::IsLocked(thePath))
{
DMSG(0, "NormFileObject::Open() Error trying to open locked file for recv!\n");
return false;
}
else
{
if (file.Open(thePath, O_WRONLY | O_CREAT | O_TRUNC))
{
file.Lock();
}
else
{
DMSG(0, "NormFileObject::Open() recv file.Open() error!\n");
return false;
}
}
//block_size = NormObjectSize(server->BlockSize()) *
// NormObjectSize(server->SegmentSize());
}
else
{
// We're sending this file
if (file.Open(thePath, O_RDONLY))
{
UINT32 size = file.GetSize();
if (size)
{
if (!NormObject::Open(size, infoPtr, infoLen))
{
DMSG(0, "NormFileObject::Open() send object open error\n");
Close();
return false;
}
}
else
{
DMSG(0, "NormFileObject::Open() send file.GetSize() error!\n");
file.Close();
return false;
}
}
else
{
DMSG(0, "NormFileObject::Open() send file.Open() error!\n");
return false;
}
}
large_block_length = NormObjectSize(large_block_size) * segment_size;
small_block_length = NormObjectSize(small_block_size) * segment_size;
strncpy(path, thePath, PATH_MAX);
unsigned int len = strlen(thePath);
len = MIN(len, PATH_MAX);
if (len < PATH_MAX) path[len] = '\0';
return true;
} // end NormFileObject::Open()
bool NormFileObject::Accept(const char* thePath)
{
if (Open(thePath))
{
NormObject::Accept();
return true;
}
else
{
return false;
}
} // end NormFileObject::Accept()
void NormFileObject::Close()
{
NormObject::Close();
file.Close();
} // end NormFileObject::Close()
bool NormFileObject::WriteSegment(NormBlockId blockId,
NormSegmentId segmentId,
const char* buffer)
{
UINT16 len;
if (blockId == final_block_id)
{
if (segmentId == (GetBlockSize(blockId)-1))
len = final_segment_size;
else
len = segment_size;
}
else
{
len = segment_size;
}
// Determine segment offset from blockId::segmentId
NormObjectSize segmentOffset;
NormObjectSize segmentSize = NormObjectSize(segment_size);
if ((UINT32)blockId < large_block_count)
{
segmentOffset = large_block_length*(UINT32)blockId + segmentSize*segmentId;
}
else
{
segmentOffset = large_block_length*large_block_count; // (TBD) pre-calc this
UINT32 smallBlockIndex = (UINT32)blockId - large_block_count;
segmentOffset = segmentOffset + small_block_length*smallBlockIndex +
segmentSize*segmentId;
}
off_t offsetScaleMSB = 0xffffffff + 1;
off_t offset = (off_t)segmentOffset.LSB() + ((off_t)segmentOffset.MSB() * offsetScaleMSB);
if (offset != file.GetOffset())
{
if (!file.Seek(offset)) return false;
}
UINT16 nbytes = file.Write(buffer, len);
return (nbytes == len);
} // end NormFileObject::WriteSegment()
UINT16 NormFileObject::ReadSegment(NormBlockId blockId,
NormSegmentId segmentId,
char* buffer)
{
// Determine segment length from blockId::segmentId
UINT16 len;
if (blockId == final_block_id)
{
if (segmentId == (GetBlockSize(blockId)-1))
len = final_segment_size;
else
len = segment_size;
}
else
{
len = segment_size;
}
// Determine segment offset from blockId::segmentId
NormObjectSize segmentOffset;
NormObjectSize segmentSize = NormObjectSize(segment_size);
if ((UINT32)blockId < large_block_count)
{
segmentOffset = large_block_length*(UINT32)blockId + segmentSize*segmentId;
}
else
{
segmentOffset = large_block_length*large_block_count; // (TBD) pre-calc this
UINT32 smallBlockIndex = (UINT32)blockId - large_block_count;
segmentOffset = segmentOffset + small_block_length*smallBlockIndex +
segmentSize*segmentId;
}
off_t offsetScaleMSB = 0xffffffff + 1;
off_t offset = (off_t)segmentOffset.LSB() + ((off_t)segmentOffset.MSB() * offsetScaleMSB);
if (offset != file.GetOffset())
{
if (!file.Seek(offset))
return false;
}
UINT16 nbytes = file.Read(buffer, len);
return (len == nbytes) ? len : 0;
} // end NormFileObject::ReadSegment()
/////////////////////////////////////////////////////////////////
//
// NormStreamObject Implementation
//
NormStreamObject::NormStreamObject(class NormSession* theSession,
class NormServerNode* theServer,
const NormObjectId& objectId)
: NormObject(STREAM, theSession, theServer, objectId),
stream_sync(false), flush_pending(false), msg_start(true)
{
}
NormStreamObject::~NormStreamObject()
{
Close();
}
bool NormStreamObject::Open(unsigned long bufferSize,
const char* infoPtr,
UINT16 infoLen)
{
if (!bufferSize)
{
DMSG(0, "NormStreamObject::Open() zero bufferSize error\n");
return false;
}
UINT16 segmentSize, numData;
if (server)
{
segmentSize = server->SegmentSize();
numData = server->BlockSize();
}
else
{
segmentSize = session->ServerSegmentSize();
numData = session->ServerBlockSize();
}
NormObjectSize blockSize((UINT32)segmentSize * (UINT32)numData);
NormObjectSize numBlocks = NormObjectSize((UINT32)bufferSize) / blockSize;
ASSERT(0 == numBlocks.MSB());
// Buffering requires at least 2 blocks
numBlocks = MAX(2, numBlocks.LSB());
unsigned long numSegments = numBlocks.LSB() * numData;
if (!block_pool.Init(numBlocks.LSB(), numData))
{
DMSG(0, "NormStreamObject::Open() block_pool init error\n");
Close();
return false;
}
if (!segment_pool.Init(numSegments, segmentSize+NormDataMsg::GetStreamPayloadHeaderLength()+1))
{
DMSG(0, "NormStreamObject::Open() segment_pool init error\n");
Close();
return false;
}
if (!stream_buffer.Init(numBlocks.LSB()))
{
DMSG(0, "NormStreamObject::Open() stream_buffer init error\n");
Close();
return false;
}
// (TBD) we really only need one set of indexes
// since our objects are exclusively read _or_ write
write_index.block = write_index.segment = 0;
read_index.block = read_index.segment = 0;
write_offset = read_offset = 0;
if (!server)
{
if (!NormObject::Open(NormObjectSize((UINT32)bufferSize), infoPtr, infoLen))
{
DMSG(0, "NormStreamObject::Open() object open error\n");
Close();
return false;
}
}
flush_pending = false;
msg_start = true;
return true;
} // end NormStreamObject::Open()
bool NormStreamObject::Accept(unsigned long bufferSize)
{
if (Open(bufferSize))
{
NormObject::Accept();
return true;
}
else
{
return false;
}
} // end NormStreamObject::Accept()
void NormStreamObject::Close()
{
NormObject::Close();
write_offset = read_offset = 0;
NormBlock* b;
while ((b = stream_buffer.Find(stream_buffer.RangeLo())))
{
stream_buffer.Remove(b);
b->EmptyToPool(segment_pool);
block_pool.Put(b);
}
stream_buffer.Destroy();
segment_pool.Destroy();
block_pool.Destroy();
} // end NormStreamObject::Close()
bool NormStreamObject::LockBlocks(NormBlockId nextId, NormBlockId lastId)
{
while (nextId <= lastId)
{
NormBlock* block = stream_buffer.Find(nextId);
if (block)
{
block->SetPending(0, ndata);
}
else
{
return false;
}
nextId++;
}
return true;
} // end NormStreamObject::LockBlocks()
bool NormStreamObject::LockSegments(NormBlockId blockId, NormSegmentId firstId, NormSegmentId lastId)
{
NormBlock* block = stream_buffer.Find(blockId);
if (block)
{
ASSERT(firstId <= lastId);
block->SetPending(firstId, (lastId - firstId + 1));
return true;
}
else
{
return false;
}
} // end NormStreamObject::LockSegments()
bool NormStreamObject::StreamUpdateStatus(NormBlockId blockId)
{
if (stream_sync)
{
if (blockId < stream_sync_id)
{
// it's an old block or stream is _very_ broken
// (nothing to update)
return true;
}
else
{
if (blockId < stream_next_id)
{
// it's pending or complete (nothing to update)
return true;
}
else
{
if (pending_mask.IsSet())
{
if (pending_mask.CanSet(blockId))
{
pending_mask.SetBits(stream_next_id, blockId - stream_next_id + 1);
stream_next_id = blockId + 1;
// Handle potential sync block id wrap
NormBlockId delta = stream_next_id - stream_sync_id;
if (delta > NormBlockId(2*pending_mask.Size()))
GetFirstPending(stream_sync_id);
return true;
}
else
{
// Stream broken
//DMSG(0, "NormObject::StreamUpdateStatus() broken 1 ...\n");
return false;
}
}
else
{
NormBlockId delta = blockId - stream_next_id + 1;
if (delta > NormBlockId(pending_mask.Size()))
{
// Stream broken
//DMSG(0, "NormObject::StreamUpdateStatus() broken 2 ...\n");
return false;
}
else
{
pending_mask.SetBits(blockId, pending_mask.Size());
stream_next_id = blockId + NormBlockId(pending_mask.Size());
// Handle potential sync block id wrap
delta = stream_next_id - stream_sync_id;
if (delta > NormBlockId(2*pending_mask.Size()))
stream_sync_id = blockId;
return true;
}
}
}
}
}
else
{
// For now, let stream begin anytime
pending_mask.Clear();
pending_mask.SetBits(blockId, pending_mask.Size());
stream_sync = true;
stream_sync_id = blockId;
stream_next_id = blockId + pending_mask.Size();
read_index.block = blockId;
return true;
}
} // end NormStreamObject::StreamUpdateStatus()
UINT16 NormStreamObject::ReadSegment(NormBlockId blockId,
NormSegmentId segmentId,
char* buffer)
{
// (TBD) compare blockId with stream_buffer.RangeLo() and stream_buffer.RangeHi()
NormBlock* block = stream_buffer.Find(blockId);
if (!block)
{
//DMSG(0, "NormStreamObject::ReadSegment() stream starved (1)\n");
return false;
}
if ((blockId == write_index.block) &&
(segmentId >= write_index.segment))
{
//DMSG(0, "NormStreamObject::ReadSegment() stream starved (2)\n");
return false;
}
block->UnsetPending(segmentId);
char* segment = block->Segment(segmentId);
ASSERT(segment != NULL);
UINT16 segmentLength = NormDataMsg::ReadStreamPayloadLength(segment);
ASSERT(segmentLength <= segment_size);
UINT16 payloadMax = segment_size + NormDataMsg::GetStreamPayloadHeaderLength();
UINT16 payloadLength = segmentLength+NormDataMsg::GetStreamPayloadHeaderLength();
#ifdef SIMULATE
payloadMax = MIN(payloadMax, SIM_PAYLOAD_MAX);
UINT16 copyMax = MIN(payloadMax, payloadLength);
memcpy(buffer, segment, copyMax);
#else
memcpy(buffer, segment, payloadLength);
#endif // SIMULATE
buffer[payloadMax] = segment[payloadMax];
return payloadLength;
} // end NormStreamObject::ReadSegment()
bool NormStreamObject::WriteSegment(NormBlockId blockId,
NormSegmentId segmentId,
const char* segment)
{
/*if ((blockId < read_index.block) ||
((blockId == read_index.block) &&
(segmentId < read_index.segment)))
{
//DMSG(0, "NormStreamObject::WriteSegment() block/segment < read_index!?\n");
return false;
}*/
UINT32 segmentOffset = NormDataMsg::ReadStreamPayloadOffset(segment);
// if (segmentOffset < read_offset)
UINT32 diff = segmentOffset - read_offset;
if ((diff > 0x80000000) || ((0x80000000 == diff) && (segmentOffset > read_offset)))
{
DMSG(0, "NormStreamObject::WriteSegment() diff:%lu segmentOffset:%lu < read_offset:%lu \n",
diff, segmentOffset, read_offset);
return false;
}
NormBlock* block = stream_buffer.Find(blockId);
if (!block)
{
bool broken = false;
// Prune (if necessary) stream_buffer (stream might be broken)
while (!stream_buffer.CanInsert(blockId) || block_pool.IsEmpty())
{
block = stream_buffer.Find(stream_buffer.RangeLo());
if (block->IsPending()) broken = true;
// This loop feeds any received user data segments to the application
// (if the application doesn't want the data, it's lost)
while (block->IsPending())
{
// Notify app for stream data salvage
read_index.block = block->Id();
block->GetFirstPending(read_index.segment);
NormBlock* tempBlock = block;
UINT32 tempOffset = read_offset;
session->Notify(NormController::RX_OBJECT_UPDATE, server, this);
block = stream_buffer.Find(stream_buffer.RangeLo());
if (tempBlock == block)
{
if (tempOffset == read_offset)
{
// App didn't want any data here, purge segment
DMSG(0, "NormStreamObject::WriteSegment() app didn't want data ?!\n");
ASSERT(0);
char* s = block->DetachSegment(read_index.segment);
segment_pool.Put(s);
block->UnsetPending(read_index.segment);
}
}
else
{
// App consumed block via Read()
block = NULL;
break;
}
}
if (block)
{
// if the app didn't consume the block, we must
// return it to the pool
ASSERT(!block->IsPending());
stream_buffer.Remove(block);
block->EmptyToPool(segment_pool);
block_pool.Put(block);
}
}
block = block_pool.Get();
block->SetId(blockId);
block->ClearPending();
bool success = stream_buffer.Insert(block);
ASSERT(success);
if (broken)
{
DMSG(4, "NormStreamObject::WriteSegment() node>%lu obj>%hu blk>%lu seg>%hu broken stream ...\n",
LocalNodeId(), (UINT16)id, (UINT32)blockId, (UINT16)segmentId);
NormBlock* first = stream_buffer.Find(stream_buffer.RangeLo());
read_index.block = first->Id();
read_index.segment = 0;
}
}
// Make sure this segment hasn't already been written
if(!block->Segment(segmentId))
{
char* s = segment_pool.Get();
ASSERT(s != NULL); // for now, this should always succeed
UINT16 payloadLength = NormDataMsg::ReadStreamPayloadLength(segment) + NormDataMsg::GetStreamPayloadHeaderLength();
UINT16 payloadMax = segment_size + NormDataMsg::GetStreamPayloadHeaderLength();
#ifdef SIMULATE
payloadMax = MIN(SIM_PAYLOAD_MAX, payloadMax);
payloadLength = MIN(payloadMax, payloadLength);
#endif // SIMULATE
memcpy(s, segment, payloadLength);
s[payloadMax] = segment[payloadMax];
block->AttachSegment(segmentId, s);
block->SetPending(segmentId);
ASSERT(block->Segment(segmentId) == s);
}
return true;
} // end NormStreamObject::WriteSegment()
void NormStreamObject::Prune(NormBlockId blockId)
{
bool resync = false;
NormBlock* block;
while ((block = block_buffer.Find(block_buffer.RangeLo())))
{
if (block->Id() < blockId)
{
resync = true;
pending_mask.Unset(block->Id());
block_buffer.Remove(block);
server->PutFreeBlock(block);
}
else
{
break;
}
}
NormBlockId firstId;
if (GetFirstPending(firstId))
{
if (firstId < blockId)
{
resync = true;
UINT32 count = blockId - firstId;
pending_mask.UnsetBits(firstId, count);
}
}
if (resync) server->IncrementResyncCount();
StreamUpdateStatus(blockId);
} // end NormStreamObject::Prune()
// Sequential (in order) read/write routines (TBD) Add a "Seek()" method
bool NormStreamObject::Read(char* buffer, unsigned int* buflen, bool findMsgStart)
{
unsigned int bytesRead = 0;
unsigned int bytesToRead = *buflen;
while (bytesToRead > 0)
{
NormBlock* block = stream_buffer.Find(read_index.block);
if (!block)
{
//DMSG(0, "NormStreamObject::Read() stream buffer empty (1)\n");
*buflen = bytesRead;
return true;
}
char* segment = block->Segment(read_index.segment);
if (!segment)
{
//DMSG(0, "NormStreamObject::Read(%lu:%hu) stream buffer empty (2)\n",
// (UINT32)read_index.block, read_index.segment);
*buflen = bytesRead;
return true;
}
UINT32 segmentOffset = NormDataMsg::ReadStreamPayloadOffset(segment);
// if (read_offset < segmentOffset)
UINT32 diff = read_offset - segmentOffset;
if ((diff > 0x80000000) || ((0x80000000 == diff) && (read_offset > segmentOffset)))
{
DMSG(0, "NormStreamObject::Read() node>%lu broken stream!\n", LocalNodeId());
read_offset = segmentOffset;
*buflen = bytesRead;
return false;
}
UINT32 index = read_offset - segmentOffset;
UINT16 length = NormDataMsg::ReadStreamPayloadLength(segment);
if (index >= length)
{
DMSG(0, "NormStreamObject::Read() node>%lu mangled stream! index:%hu length:%hu\n",
LocalNodeId(), index, length);
read_offset = segmentOffset;
*buflen = bytesRead;
ASSERT(0);
return false;
}
UINT16 count = length - index;
count = MIN(count, bytesToRead);
if (findMsgStart)
{
bool msgStart;
if (0 != index)
{
msgStart = false;
}
else
{
UINT16 payloadMax = segment_size+NormDataMsg::GetStreamPayloadHeaderLength();
#ifdef SIMULATE
payloadMax = MIN(payloadMax, SIM_PAYLOAD_MAX);
#endif // if/else SIMULATE
msgStart = (NormObjectMsg::FLAG_MSG_START == segment[payloadMax]);
}
if (!msgStart)
{
block->DetachSegment(read_index.segment);
segment_pool.Put(segment);
block->UnsetPending(read_index.segment++);
if (read_index.segment >= ndata)
{
stream_buffer.Remove(block);
block->EmptyToPool(segment_pool);
block_pool.Put(block);
read_index.block++;
read_index.segment = 0;
}
continue;
}
}
#ifdef SIMULATE
UINT16 simCount = index + count + NormDataMsg::GetStreamPayloadHeaderLength();
simCount = (simCount < SIM_PAYLOAD_MAX) ? (SIM_PAYLOAD_MAX - simCount) : 0;
memcpy(buffer+bytesRead, segment+index+NormDataMsg::GetStreamPayloadHeaderLength(), simCount);
#else
memcpy(buffer+bytesRead, segment+index+NormDataMsg::GetStreamPayloadHeaderLength(), count);
#endif // if/else SIMULATE
index += count;
bytesRead += count;
read_offset += count;
bytesToRead -= count;
if (index >= length)
{
block->DetachSegment(read_index.segment);
segment_pool.Put(segment);
block->UnsetPending(read_index.segment++);
if (read_index.segment >= ndata)
{
stream_buffer.Remove(block);
block->EmptyToPool(segment_pool);
block_pool.Put(block);
read_index.block++;
read_index.segment = 0;
}
}
} // end while (len > 0)
*buflen = bytesRead;
return true;
} // end NormStreamObject::Read()
unsigned long NormStreamObject::Write(const char* buffer, unsigned long len,
FlushType flushType, bool eom, bool push)
{
unsigned long nBytes = 0;
do
{
NormBlock* block = stream_buffer.Find(write_index.block);
if (!block)
{
if (!(block = block_pool.Get()))
{
block = stream_buffer.Find(stream_buffer.RangeLo());
ASSERT(block);
if (push)
{
NormBlockId blockId = block->Id();
pending_mask.Unset(blockId);
repair_mask.Unset(blockId);
NormBlock* b = FindBlock(blockId);
if (b)
{
block_buffer.Remove(b);
session->ServerPutFreeBlock(b);
}
}
else if (block->IsPending())
{
DMSG(0, "NormStreamObject::Write() stream buffer full (1) len:%d eom:%d\n", len, eom);
break;
}
stream_buffer.Remove(block);
block->EmptyToPool(segment_pool);
}
block->SetId(write_index.block);
block->ClearPending();
bool success = stream_buffer.Insert(block);
ASSERT(success);
}
char* segment = block->Segment(write_index.segment);
if (!segment)
{
if (!(segment = segment_pool.Get()))
{
NormBlock* b = stream_buffer.Find(stream_buffer.RangeLo());
ASSERT(b != block);
if (push)
{
NormBlockId blockId = block->Id();
pending_mask.Unset(blockId);
repair_mask.Unset(blockId);
NormBlock* c = FindBlock(blockId);
if (c)
{
block_buffer.Remove(c);
session->ServerPutFreeBlock(c);
}
}
else if (b->IsPending())
{
DMSG(0, "NormStreamObject::Write() stream buffer full (2)\n");
break;
}
stream_buffer.Remove(b);
b->EmptyToPool(segment_pool);
block_pool.Put(b);
segment = segment_pool.Get();
ASSERT(segment);
}
NormDataMsg::WriteStreamPayloadOffset(segment, write_offset);
NormDataMsg::WriteStreamPayloadLength(segment, 0);
block->AttachSegment(write_index.segment, segment);
}
UINT16 index = NormDataMsg::ReadStreamPayloadLength(segment);
if (0 == index)
{
char msgStartValue = 0;
if (msg_start && len)
{
ASSERT(0 == index);
msgStartValue = NormObjectMsg::FLAG_MSG_START;
msg_start = false;
}
UINT16 payloadMax = segment_size+NormDataMsg::GetStreamPayloadHeaderLength();
#ifdef SIMULATE
payloadMax = MIN(SIM_PAYLOAD_MAX, payloadMax);
#endif // SIMULATE
segment[payloadMax] = msgStartValue;
}
else
{
msg_start = false;
}
UINT16 count = (UINT16)(len - nBytes);
UINT16 space = segment_size - index;
count = MIN(count, space);
#ifdef SIMULATE
UINT16 simCount = index + NormDataMsg::GetStreamPayloadHeaderLength();
simCount = (simCount < SIM_PAYLOAD_MAX) ? (SIM_PAYLOAD_MAX - simCount) : 0;
simCount = MIN(count, simCount);
memcpy(segment+index+NormDataMsg::GetStreamPayloadHeaderLength(), buffer+nBytes, simCount);
#else
memcpy(segment+index+NormDataMsg::GetStreamPayloadHeaderLength(), buffer+nBytes, count);
#endif // if/else SIMULATE
NormDataMsg::WriteStreamPayloadLength(segment, index+count);
nBytes += count;
write_offset += count;
// Is the segment full? or flushing
if ((count == space) || ((FLUSH_NONE != flushType) && (0 != index) && (nBytes == len)))
{
block->SetPending(write_index.segment);
if (++write_index.segment >= ndata)
{
write_index.block++;
write_index.segment = 0;
}
}
} while (nBytes < len);
// if this was end-of-message next Write() will be considered a new message
if (nBytes == len)
{
if (eom)
msg_start = true;
if (FLUSH_ACTIVE == flushType)
flush_pending = true;
else
flush_pending = false;
}
else
{
flushType = FLUSH_NONE;
}
if (nBytes || (FLUSH_NONE != flushType)) session->TouchServer();
return nBytes;
} // end NormStreamObject::Write()
#ifdef SIMULATE
/////////////////////////////////////////////////////////////////
//
// NormSimObject Implementation (dummy NORM_OBJECT_FILE or NORM_OBJECT_DATA)
//
NormSimObject::NormSimObject(class NormSession* theSession,
class NormServerNode* theServer,
const NormObjectId& objectId)
: NormObject(FILE, theSession, theServer, objectId)
{
}
NormSimObject::~NormSimObject()
{
}
UINT16 NormSimObject::ReadSegment(NormBlockId blockId,
NormSegmentId segmentId,
char* buffer)
{
// Determine segment length
UINT16 len;
if (blockId == final_block_id)
{
if (segmentId == (GetBlockSize(blockId)-1))
len = final_segment_size;
else
len = segment_size;
}
else
{
len = segment_size;
}
return len;
} // end NormSimObject::ReadSegment()
#endif // SIMULATE
/////////////////////////////////////////////////////////////////
//
// NormObjectTable Implementation
//
NormObjectTable::NormObjectTable()
: table((NormObject**)NULL), range_max(0), range(0),
count(0), size(0,0)
{
}
NormObjectTable::~NormObjectTable()
{
Destroy();
}
bool NormObjectTable::Init(UINT16 rangeMax, UINT16 tableSize)
{
if (table) Destroy();
// Make sure tableSize is greater than 0 and 2^n
if (!rangeMax || !tableSize) return false;
if (0 != (tableSize & 0x07)) tableSize = (tableSize >> 3) + 1;
if (!(table = new NormObject*[tableSize]))
{
DMSG(0, "NormObjectTable::Init() table allocation error: %s\n", strerror(errno));
return false;
}
memset(table, 0, tableSize*sizeof(char*));
hash_mask = tableSize - 1;
range_max = rangeMax;
range = 0;
return true;
} // end NormObjectTable::Init()
void NormObjectTable::Destroy()
{
if (table)
{
NormObject* obj;
while((obj = Find(range_lo)))
{
Remove(obj);
delete obj;
}
delete []table;
table = (NormObject**)NULL;
range = range_max = 0;
}
} // end NormObjectTable::Destroy()
NormObject* NormObjectTable::Find(const NormObjectId& objectId) const
{
if (range)
{
if ((objectId < range_lo) || (objectId > range_hi)) return (NormObject*)NULL;
NormObject* theObject = table[((UINT16)objectId) & hash_mask];
while (theObject && (objectId != theObject->Id())) theObject = theObject->next;
return theObject;
}
else
{
return (NormObject*)NULL;
}
} // end NormObjectTable::Find()
bool NormObjectTable::CanInsert(NormObjectId objectId) const
{
if (0 != range)
{
if (objectId < range_lo)
{
if ((range_lo - objectId + range) > range_max)
return false;
else
return true;
}
else if (objectId > range_hi)
{
if ((objectId - range_hi + range) > range_max)
return false;
else
return true;
}
else
{
return true;
}
}
else
{
return true;
}
} // end NormObjectTable::CanInsert()
bool NormObjectTable::Insert(NormObject* theObject)
{
const NormObjectId& objectId = theObject->Id();
if (!range)
{
range_lo = range_hi = objectId;
range = 1;
}
if (objectId < range_lo)
{
UINT16 newRange = range_lo - objectId + range;
if (newRange > range_max) return false;
range_lo = objectId;
range = newRange;
}
else if (objectId > range_hi)
{
UINT16 newRange = objectId - range_hi + range;
if (newRange > range_max) return false;
range_hi = objectId;
range = newRange;
}
UINT16 index = ((UINT16)objectId) & hash_mask;
NormObject* prev = NULL;
NormObject* entry = table[index];
while (entry && (entry->Id() < objectId))
{
prev = entry;
entry = entry->next;
}
if (prev)
prev->next = theObject;
else
table[index] = theObject;
ASSERT((entry ? (objectId != entry->Id()) : true));
theObject->next = entry;
count++;
size = size + theObject->Size();
return true;
} // end NormObjectTable::Insert()
bool NormObjectTable::Remove(const NormObject* theObject)
{
ASSERT(theObject);
const NormObjectId& objectId = theObject->Id();
if (range)
{
if ((objectId < range_lo) || (objectId > range_hi)) return false;
UINT16 index = ((UINT16)objectId) & hash_mask;
NormObject* prev = NULL;
NormObject* entry = table[index];
while (entry && (entry->Id() != objectId))
{
prev = entry;
entry = entry->next;
}
if (entry != theObject) return false;
if (prev)
prev->next = entry->next;
else
table[index] = entry->next;
if (range > 1)
{
if (objectId == range_lo)
{
// Find next entry for range_lo
UINT16 i = index;
UINT16 endex;
if (range <= hash_mask)
endex = (index + range - 1) & hash_mask;
else
endex = index;
entry = NULL;
UINT16 offset = 0;
NormObjectId nextId = range_hi;
do
{
++i &= hash_mask;
offset++;
if ((entry = table[i]))
{
NormObjectId id = (UINT16)index + offset;
while(entry && (entry->Id() != id))
{
if ((entry->Id() > objectId) &&
(entry->Id() < nextId)) nextId = entry->Id();
entry = entry->next;
}
if (entry) break;
}
} while (i != endex);
if (entry)
range_lo = entry->Id();
else
range_lo = nextId;
range = range_hi - range_lo + 1;
}
else if (objectId == range_hi)
{
// Find prev entry for range_hi
UINT16 i = index;
UINT16 endex;
if (range <= hash_mask)
endex = (index - range + 1) & hash_mask;
else
endex = index;
entry = NULL;
UINT16 offset = 0;
//printf("preving i:%lu endex:%lu lo:%lu hi:%lu\n", i, endex, (UINT16)range_lo, (UINT16) range_hi);
NormObjectId prevId = range_lo;
do
{
--i &= hash_mask;
offset++;
if ((entry = table[i]))
{
NormObjectId id = (UINT16)index - offset;
//printf("Looking for id:%lu at index:%lu\n", (UINT16)id, i);
while(entry && (entry->Id() != id))
{
if ((entry->Id() < objectId) &&
(entry->Id() > prevId)) prevId = entry->Id();
entry = entry->next;
}
if (entry) break;
}
} while (i != endex);
if (entry)
range_hi = entry->Id();
else
range_hi = prevId;
range = range_hi - range_lo + 1;
}
}
else
{
range = 0;
}
count--;
size = size - theObject->Size();
return true;
}
else
{
return false;
}
} // end NormObjectTable::Remove()
NormObjectTable::Iterator::Iterator(const NormObjectTable& objectTable)
: table(objectTable), reset(true)
{
}
NormObject* NormObjectTable::Iterator::GetNextObject()
{
if (reset)
{
if (table.range)
{
reset = false;
index = table.range_lo;
return table.Find(index);
}
else
{
return (NormObject*)NULL;
}
}
else
{
if (table.range &&
(index < table.range_hi) &&
(index >= table.range_lo))
{
// Find next entry _after_ current "index"
UINT16 i = index;
UINT16 endex;
if ((UINT16)(table.range_hi - index) <= table.hash_mask)
endex = table.range_hi & table.hash_mask;
else
endex = index;
UINT16 offset = 0;
NormObjectId nextId = table.range_hi;
do
{
++i &= table.hash_mask;
offset++;
NormObjectId id = (UINT16)index + offset;
NormObject* entry = table.table[i];
while ((NULL != entry) && (entry->Id() != id))
{
if ((entry->Id() > index) && (entry->Id() < nextId))
nextId = entry->Id();
entry = table.Next(entry);
}
if (entry)
{
index = entry->Id();
return entry;
}
} while (i != endex);
// If we get here, use nextId value
index = nextId;
return table.Find(nextId);
}
else
{
return (NormObject*)NULL;
}
}
} // end NormObjectTable::Iterator::GetNextObject()
NormObject* NormObjectTable::Iterator::GetPrevObject()
{
if (reset)
{
if (table.range)
{
reset = false;
index = table.range_hi;
return table.Find(index);
}
else
{
return (NormObject*)NULL;
}
}
else
{
if (table.range &&
(index <= table.range_hi) &&
(index > table.range_lo))
{
// Find prev entry _before_ current "index"
UINT16 i = index;
UINT16 endex;
if ((UINT16)(index - table.range_lo) <= table.hash_mask)
endex = table.range_lo & table.hash_mask;
else
endex = index;
UINT16 offset = 0;
NormObjectId nextId = table.range_hi;
do
{
--i &= table.hash_mask;
offset--;
NormObjectId id = (UINT16)index + offset;
NormObject* entry = table.table[i];
while ((NULL != entry ) && (entry->Id() != id))
{
if ((entry->Id() > index) && (entry->Id() < nextId))
nextId = entry->Id();
entry = table.Next(entry);
}
if (entry)
{
index = entry->Id();
return entry;
}
} while (i != endex);
// If we get here, use nextId value
index = nextId;
return table.Find(nextId);
}
else
{
return (NormObject*)NULL;
}
}
} // end NormObjectTable::Iterator::GetPrevObject()