public void SwitchToNewIndex(int index)
{
if (BlockIndex != -1)
{
BlockIndex = -1;
}
BlockBuffer = ParentVolume.GetBlockBuffer(index);
if (BlockBuffer != null)
{
BlockIndex = index;
}
}
public bool SearchEntry(byte[] input, int inputLen, out int result)
{
result = 0;
SpanReader sr = new SpanReader(BlockBuffer);
sr.Position = 2;
int entryCount = sr.ReadInt16() / 2;
ushort blockSize = ParentVolume.GetBlockSize();
// Check first
sr.Position = blockSize - 0x08;
short entryOffset = sr.ReadInt16();
short entryLength = sr.ReadInt16();
sr.Position = entryOffset;
byte[] entryIndexer = sr.ReadBytes(entryLength);
int diff = DebugReader.CompareEntries(input, inputLen, entryIndexer, entryLength);
if (diff < 0)
{
result = 0;
return(false);
}
// Check last
sr.Position = blockSize - (entryCount * 0x08);
entryOffset = sr.ReadInt16();
entryLength = sr.ReadInt16();
sr.Position = entryOffset;
entryIndexer = sr.ReadBytes(entryLength);
diff = DebugReader.CompareEntries(input, inputLen, entryIndexer, entryLength);
if (diff > 0)
{
result = -entryCount;
return(false);
}
int min = 0;
int max = entryCount;
int mid = (min + max) / 2;
while (min < max)
{
if (max - min < 8)
{
mid = min;
int baseOffset = blockSize - (mid * 0x08);
int entryitorOffset = baseOffset;
if (max < min)
{
return(false);
}
while (min <= max)
{
entryitorOffset -= 0x08;
sr.Position = entryitorOffset;
entryOffset = sr.ReadInt16();
sr.Position = (mid * 0x08 - blockSize) + baseOffset + entryitorOffset;
sr.Position += 2;
entryLength = sr.ReadInt16();
sr.Position = entryOffset;
entryIndexer = sr.ReadBytes(entryLength);
diff = DebugReader.CompareEntries(input, inputLen, entryIndexer, entryLength);
if (diff < 1)
{
result = min;
return(diff == 0);
}
min++;
}
return(false);
}
sr.Position = blockSize - (mid * 0x08);
entryOffset = sr.ReadInt16();
entryLength = sr.ReadInt16();
sr.Position = entryOffset;
entryIndexer = sr.ReadBytes(entryLength);
diff = DebugReader.CompareEntries(input, inputLen, entryIndexer, entryLength);
if (diff == 0)
{
result = mid - 1;
return(true);
}
else if (diff > 0)
{
min = mid;
}
else
{
max = mid;
}
mid = (min + max) / 2;
}
throw new Exception("Failed to bsearch the entry.");
}
public int SearchBlockIndex(byte[] input, int inputLen)
{
SpanReader sr = new SpanReader(BlockBuffer);
sr.Position = 2;
int indexEntryCount = sr.ReadInt16();
int realEntryCount = (((indexEntryCount - 1) / 2) - 1);
ushort blockSize = ParentVolume.GetBlockSize();
if (indexEntryCount == 1)
{
// return the first
sr.Position = blockSize - 4;
return(sr.ReadInt32());
}
// First
sr.Position = blockSize - 0x08;
short entryOffset = sr.ReadInt16();
short entryLength = sr.ReadInt16();
sr.Position = entryOffset;
byte[] entryIndexer = sr.ReadBytes(entryLength);
int diff = DebugReader.CompareEntries(input, inputLen, entryIndexer, entryLength);
if (diff < 0)
{
// return the first block index
sr.Position = (blockSize - 0x08) + 4;
return(sr.ReadInt32());
}
// Last
sr.Position = blockSize - (realEntryCount * 0x08);
entryOffset = sr.ReadInt16();
entryLength = sr.ReadInt16();
sr.Position = entryOffset;
entryIndexer = sr.ReadBytes(entryLength);
diff = DebugReader.CompareEntries(input, inputLen, entryIndexer, entryLength);
if (diff > 0)
{
// return the last block index
sr.Position = blockSize - (realEntryCount * 0x08) + 4;
return(sr.ReadInt32());
}
int min = 0;
int max = realEntryCount;
int mid = (min + max) / 2;
while (min < max)
{
if (max - min < 8)
{
mid = min;
int baseOffset = blockSize - (mid * 0x08);
int entryitorOffset = baseOffset;
if (max < min)
{
return(-1);
}
while (min <= max)
{
entryitorOffset -= 0x08;
sr.Position = entryitorOffset;
entryOffset = sr.ReadInt16();
int entryIndexOffset = (mid * 0x08 - blockSize) + baseOffset + entryitorOffset;
sr.Position = entryIndexOffset + 2;
entryLength = sr.ReadInt16();
sr.Position = entryOffset;
entryIndexer = sr.ReadBytes(entryLength);
diff = DebugReader.CompareEntries(input, inputLen, entryIndexer, entryLength);
if (diff == 0)
{
sr.Position = entryIndexOffset - 4;
return(sr.ReadInt32());
}
else if (diff < 0)
{
sr.Position = entryIndexOffset + 4;
return(sr.ReadInt32());
}
min++;
}
return(-1);
}
sr.Position = blockSize - (mid * 0x08);
entryOffset = sr.ReadInt16();
entryLength = sr.ReadInt16();
sr.Position = entryOffset;
entryIndexer = sr.ReadBytes(entryLength);
diff = DebugReader.CompareEntries(input, inputLen, entryIndexer, entryLength);
if (diff == 0)
{
// return the matching index
sr.Position = blockSize - (mid * 0x08) + 4;
return(sr.ReadInt32());
}
else if (diff > 0)
{
min = mid;
}
else
{
max = mid;
}
mid = (min + max) / 2;
}
throw new Exception("Failed to bsearch for the block entry.");
}
