// Zapper.cpp
// Implements the cZapper class representing the processor that actually zaps blocks and entities
#include "Globals.h"
#include "WorldStorage/FastNBT.h"
#include "StringCompression.h"
#include "zlib/zlib.h"
#include "Zapper.h"
/** The maximum size of an inflated chunk; raw chunk data is 192 KiB, allow 64 KiB more of entities */
#define CHUNK_INFLATE_MAX 256 KiB
cZapper::cZapper(const AString & a_MCAFolder) :
m_MCAFolder(a_MCAFolder)
{
}
void cZapper::ZapRegions(const cRegionVector & a_Regions)
{
for (cRegionVector::const_iterator itr = a_Regions.begin(), end = a_Regions.end(); itr != end; ++itr)
{
int MinAnvX, MinAnvZ;
int MaxAnvX, MaxAnvZ;
BlockToMCA(itr->m_MinX, itr->m_MinZ, MinAnvX, MinAnvZ);
BlockToMCA(itr->m_MaxX, itr->m_MaxZ, MaxAnvX, MaxAnvZ);
for (int x = MinAnvX; x <= MaxAnvX; x++)
{
for (int z = MinAnvZ; z <= MaxAnvZ; z++)
{
ZapRegionInMCAFile(*itr, x, z);
}
}
} // for itr - a_Regions
}
void cZapper::BlockToMCA(int a_BlockX, int a_BlockZ, int & a_MCAX, int & a_MCAZ)
{
// These need to be arithmetic shifts, consult your compiler documentation to see if it's so
// MSVC and GCC both use arithmetic shifts
a_MCAX = a_BlockX >> 10;
a_MCAZ = a_BlockZ >> 10;
}
void cZapper::BlockToChunk(int a_BlockX, int a_BlockZ, int & a_ChunkX, int & a_ChunkZ)
{
// These need to be arithmetic shifts, consult your compiler documentation to see if it's so
// MSVC and GCC both use arithmetic shifts
a_ChunkX = a_BlockX >> 4;
a_ChunkZ = a_BlockZ >> 4;
}
void cZapper::ZapRegionInMCAFile(const cRegion & a_Region, int a_MCAX, int a_MCAZ)
{
cFile fIn;
AString FileNameIn = Printf("%s/r.%d.%d.mca", m_MCAFolder.c_str(), a_MCAX, a_MCAZ);
if (!fIn.Open(FileNameIn, cFile::fmRead))
{
return;
}
cFile fOut;
AString FileNameOut = Printf("%s/r.%d.%d.zap", m_MCAFolder.c_str(), a_MCAX, a_MCAZ);
if (!fOut.Open(FileNameOut, cFile::fmWrite))
{
fprintf(stderr, "Cannot open temporary file \"%s\" for writing, skipping file \"%s\".", FileNameOut.c_str(), FileNameIn.c_str());
return;
}
AString DataOut;
DataOut.reserve(fIn.GetSize());
int HeaderIn[2048];
if (fIn.Read(HeaderIn, sizeof(HeaderIn)) != sizeof(HeaderIn))
{
fprintf(stderr, "Cannot read header from file \"%s\", skipping file.", FileNameIn.c_str());
}
int HeaderOut[2048];
for (int i = 0; i < 1024; i++)
{
if (HeaderIn[i] == 0)
{
// Chunk not present
HeaderOut[i] = 0;
continue;
}
AString ChunkData;
int ChunkX = a_MCAX * ChunksPerMCAX + (i % ChunksPerMCAX);
int ChunkZ = a_MCAZ * ChunksPerMCAZ + (i / ChunksPerMCAX);
LoadChunkData(fIn, HeaderIn[i], ChunkData, ChunkX, ChunkZ);
if (a_Region.TouchesChunk(ChunkX, ChunkZ))
{
ZapRegionInRawChunkData(a_Region, ChunkData, ChunkX, ChunkZ);
}
unsigned char ChunkHeader[5];
size_t DataSize = ChunkData.size() + 1;
ChunkHeader[0] = (DataSize >> 24) & 0xff;
ChunkHeader[1] = (DataSize >> 16) & 0xff;
ChunkHeader[2] = (DataSize >> 8) & 0xff;
ChunkHeader[3] = DataSize & 0xff;
ChunkHeader[4] = 2; // zlib compression
size_t Alignment = 4096 - (ChunkData.size() + 5) % 4096; // 5 bytes of the header are appended outside of ChunkData
if (Alignment > 0)
{
ChunkData.append(Alignment, (char)0);
}
HeaderOut[i] = htonl(((DataOut.size() / 4096 + 2) << 8) | ((ChunkData.size() + 5) / 4096));
DataOut.append((const char *)ChunkHeader, sizeof(ChunkHeader));
DataOut.append(ChunkData);
} // for i - chunks in fIn
for (int i = 1024; i < 2048; i++)
{
HeaderOut[i] = HeaderIn[i];
}
fIn.Close();
fOut.Write(HeaderOut, sizeof(HeaderOut));
fOut.Write(DataOut.data(), DataOut.size());
fOut.Close();
cFile::Delete(FileNameIn);
cFile::Rename(FileNameOut, FileNameIn);
}
void cZapper::LoadChunkData(cFile & a_InFile, int a_ChunkHeaderValue, AString & a_ChunkData, int a_ChunkX, int a_ChunkZ)
{
a_ChunkHeaderValue = ntohl(a_ChunkHeaderValue); // Convert from big-endian to system-endian
int ChunkOffset = (a_ChunkHeaderValue >> 8) * 4096;
int ChunkSize = (a_ChunkHeaderValue & 0xff) * 4096;
a_InFile.Seek(ChunkOffset);
unsigned char ChunkHeader[5];
a_InFile.Read(ChunkHeader, sizeof(ChunkHeader));
if (ChunkHeader[4] != 2)
{
fprintf(stderr, "Chunk [%d, %d] is compressed in an unknown scheme (%d), skipping", a_ChunkX, a_ChunkZ, ChunkHeader[4]);
return;
}
int ActualSize = (ChunkHeader[0] << 24) | (ChunkHeader[1] << 16) | (ChunkHeader[2] << 8) | ChunkHeader[3];
ActualSize -= 1; // Compression took 1 byte
a_ChunkData.resize(ActualSize);
int BytesRead = a_InFile.Read((void *)(a_ChunkData.data()), ActualSize);
if (BytesRead != ActualSize)
{
fprintf(stderr, "Chunk is truncated in file (%d bytes out of %d), skipping.", BytesRead, ActualSize);
a_ChunkData.clear();
return;
}
}
void cZapper::ZapRegionInRawChunkData(const cRegion & a_Region, AString & a_ChunkData, int a_ChunkX, int a_ChunkZ)
{
// Decompress the data:
char Uncompressed[CHUNK_INFLATE_MAX];
z_stream strm;
strm.zalloc = (alloc_func)NULL;
strm.zfree = (free_func)NULL;
strm.opaque = NULL;
inflateInit(&strm);
strm.next_out = (Bytef *)Uncompressed;
strm.avail_out = sizeof(Uncompressed);
strm.next_in = (Bytef *)a_ChunkData.data();
strm.avail_in = a_ChunkData.size();
int res = inflate(&strm, Z_FINISH);
inflateEnd(&strm);
if (res != Z_STREAM_END)
{
fprintf(stderr, "Chunk [%d, %d] failed to decompress: error %d. Skipping chunk.", a_ChunkX, a_ChunkZ, res);
return;
}
/*
// DEBUG: Output src to a file:
cFile f1;
if (f1.Open(Printf("chunk_%d_%d_in.nbt", a_ChunkX, a_ChunkZ), cFile::fmWrite))
{
f1.Write(Uncompressed, strm.total_out);
}
//*/
cParsedNBT NBT(Uncompressed, strm.total_out);
if (!NBT.IsValid())
{
fprintf(stderr, "Chunk [%d, %d] failed to parse. Skipping chunk.", a_ChunkX, a_ChunkZ);
return;
}
ZapRegionInNBTChunk(a_Region, NBT, a_ChunkX, a_ChunkZ);
cFastNBTWriter Writer;
for (int ch = NBT.GetFirstChild(0); ch >= 0; ch = NBT.GetNextSibling(ch))
{
SerializeNBTTag(NBT, ch, Writer);
}
Writer.Finish();
/*
// DEBUG: Output dst to a file:
cFile f2;
if (f2.Open(Printf("chunk_%d_%d_out.nbt", a_ChunkX, a_ChunkZ), cFile::fmWrite))
{
f2.Write(Writer.GetResult().data(), Writer.GetResult().size());
}
//*/
// Compress the serialized data into "Uncompressed" (reuse buffer)
CompressString(Writer.GetResult().data(), Writer.GetResult().size(), a_ChunkData);
}
void cZapper::ZapRegionInNBTChunk(const cRegion & a_Region, cParsedNBT & a_NBT, int a_ChunkX, int a_ChunkZ)
{
int LevelTag = a_NBT.FindChildByName(a_NBT.GetRoot(), "Level");
if (LevelTag < 0)
{
fprintf(stderr, "Cannot find Level tag in chunk [%d, %d]'s NBT. Skipping chunk.", a_ChunkX, a_ChunkZ);
return;
}
// Create a copy of the region and limit it to the current chunk:
int BlockX = a_ChunkX * 16;
int BlockZ = a_ChunkZ * 16;
cRegion Local;
Local.m_MinX = std::max(0, a_Region.m_MinX - BlockX);
Local.m_MaxX = std::min(15, a_Region.m_MaxX - BlockX);
Local.m_MinY = a_Region.m_MinY;
Local.m_MaxY = a_Region.m_MaxY;
Local.m_MinZ = std::max(0, a_Region.m_MinZ - BlockZ);
Local.m_MaxZ = std::min(15, a_Region.m_MaxZ - BlockZ);
if (a_Region.m_ShouldZapBlocks)
{
int SectionsTag = a_NBT.FindChildByName(LevelTag, "Sections");
if (SectionsTag < 0)
{
fprintf(stderr, "Cannot find the Sections tag in the Level tag in chunk [%d, %d]'s NBT. Skipping block-zapping in chunk.", a_ChunkX, a_ChunkZ);
return;
}
ZapRegionBlocksInNBT(Local, a_NBT, SectionsTag);
}
if (a_Region.m_ShouldZapEntities)
{
int EntitiesTag = a_NBT.FindChildByName(LevelTag, "Entities");
if (EntitiesTag < 0)
{
fprintf(stderr, "Cannot find the Entities tag in the Level tag in chunk [%d, %d]'s NBT. Skipping entity-zapping in chunk.", a_ChunkX, a_ChunkZ);
return;
}
ZapRegionEntitiesInNBT(Local, a_NBT, EntitiesTag);
}
}
void cZapper::ZapRegionBlocksInNBT(const cRegion & a_Region, cParsedNBT & a_NBT, int a_SectionsTag)
{
for (int Child = a_NBT.GetFirstChild(a_SectionsTag); Child >= 0; Child = a_NBT.GetNextSibling(Child))
{
int y = 0;
int SectionY = a_NBT.FindChildByName(Child, "Y");
if ((SectionY < 0) || (a_NBT.GetType(SectionY) != TAG_Byte))
{
continue;
}
y = a_NBT.GetByte(SectionY);
if ((y * 16 > a_Region.m_MaxY) || (y * 16 + 16 < a_Region.m_MinY))
{
continue;
}
int BlockDataTag = a_NBT.FindChildByName(Child, "Blocks");
int BlockMetaTag = a_NBT.FindChildByName(Child, "Data");
int BlockAddTag = a_NBT.FindChildByName(Child, "Add");
if (BlockDataTag > 0)
{
ZapRegionInNBTSectionBytes(a_Region, y, (unsigned char *)(a_NBT.GetData(BlockDataTag)));
}
if (BlockMetaTag > 0)
{
ZapRegionInNBTSectionNibbles(a_Region, y, (unsigned char *)(a_NBT.GetData(BlockMetaTag)));
}
if (BlockAddTag > 0)
{
ZapRegionInNBTSectionNibbles(a_Region, y, (unsigned char *)(a_NBT.GetData(BlockAddTag)));
}
} // for Child - Level / Sections / []
}
void cZapper::ZapRegionInNBTSectionBytes(const cRegion & a_Region, int a_SectionY, unsigned char * a_BlockBytes)
{
int MinY = std::max(0, a_Region.m_MinY - a_SectionY * 16);
int MaxY = std::min(15, a_Region.m_MaxY - a_SectionY * 16);
ASSERT(MinY >= 0);
ASSERT(MaxY >= 0);
for (int y = MinY; y <= MaxY; y++)
{
for (int z = a_Region.m_MinZ; z <= a_Region.m_MaxZ; z++)
{
for (int x = a_Region.m_MinX; x <= a_Region.m_MaxX; x++)
{
a_BlockBytes[x + z * 16 + y * 16 * 16] = 0;
}
}
}
}
void cZapper::ZapRegionInNBTSectionNibbles(const cRegion & a_Region, int a_SectionY, unsigned char * a_BlockNibbles)
{
int MinY = std::max(0, a_Region.m_MinY - a_SectionY * 16);
int MaxY = std::min(15, a_Region.m_MaxY - a_SectionY * 16);
ASSERT(MinY >= 0);
ASSERT(MaxY >= 0);
for (int y = MinY; y <= MaxY; y++)
{
for (int z = a_Region.m_MinZ; z < a_Region.m_MaxZ; z++)
{
for (int x = a_Region.m_MinX; x < a_Region.m_MaxX; x++)
{
cChunkDef::SetNibble(a_BlockNibbles, x, y, z, 0);
}
}
}
}
void cZapper::ZapRegionEntitiesInNBT(const cRegion & a_Region, cParsedNBT & a_NBT, int a_EntitiesTag)
{
// TODO
}
void cZapper::SerializeNBTTag(const cParsedNBT & a_NBT, int a_Tag, cFastNBTWriter & a_Writer)
{
switch (a_NBT.GetType(a_Tag))
{
case TAG_Byte: a_Writer.AddByte (a_NBT.GetName(a_Tag), a_NBT.GetByte (a_Tag)); break;
case TAG_Short: a_Writer.AddShort (a_NBT.GetName(a_Tag), a_NBT.GetShort (a_Tag)); break;
case TAG_Int: a_Writer.AddInt (a_NBT.GetName(a_Tag), a_NBT.GetInt (a_Tag)); break;
case TAG_Long: a_Writer.AddLong (a_NBT.GetName(a_Tag), a_NBT.GetLong (a_Tag)); break;
case TAG_Float: a_Writer.AddFloat (a_NBT.GetName(a_Tag), a_NBT.GetFloat (a_Tag)); break;
case TAG_Double: a_Writer.AddDouble (a_NBT.GetName(a_Tag), a_NBT.GetDouble(a_Tag)); break;
case TAG_ByteArray: a_Writer.AddByteArray(a_NBT.GetName(a_Tag), a_NBT.GetData (a_Tag), a_NBT.GetDataLength(a_Tag)); break;
case TAG_String: a_Writer.AddString (a_NBT.GetName(a_Tag), a_NBT.GetString(a_Tag)); break;
case TAG_IntArray:
{
std::vector<int> Data;
int NumInts = a_NBT.GetDataLength(a_Tag) / 4;
Data.reserve(NumInts);
int * OrigData = (int *)(a_NBT.GetData(a_Tag));
for (int i = 0; i < NumInts; i++)
{
Data.push_back(ntohl(OrigData[i]));
}
a_Writer.AddIntArray (a_NBT.GetName(a_Tag), &Data.front(), Data.size()); break;
}
case TAG_List:
{
a_Writer.BeginList(a_NBT.GetName(a_Tag), a_NBT.GetChildrenType(a_Tag));
for (int ch = a_NBT.GetFirstChild(a_Tag); ch >= 0; ch = a_NBT.GetNextSibling(ch))
{
SerializeNBTTag(a_NBT, ch, a_Writer);
} // for ch - children[]
a_Writer.EndList();
break;
}
case TAG_Compound:
{
a_Writer.BeginCompound(a_NBT.GetName(a_Tag));
for (int ch = a_NBT.GetFirstChild(a_Tag); ch >= 0; ch = a_NBT.GetNextSibling(ch))
{
SerializeNBTTag(a_NBT, ch, a_Writer);
} // for ch - children[]
a_Writer.EndCompound();
break;
}
default:
{
ASSERT(!"Unknown NBT tag");
break;
}
}
}
