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compressZlib: don't use a SharedBuffer but a raw u8 * pointer

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Remove usage of the SharedBuffer in zlib compression which has two problems:
* We copied the whole memory block to compress it (not good with mapblocks)
* We copied sometimes strings to SharedBuffer to SharedBuffer (2nd time)

Use this method in MapNode::serializeBulk + optimize serialization but merging 3 identical loops in a single loop
This commit is contained in:
Loic Blot 2017-07-26 23:37:44 +02:00 committed by Loïc Blot
parent 61e4877190
commit c27504a322
3 changed files with 34 additions and 40 deletions
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35
src/mapnode.cpp
View File

@ -658,7 +658,7 @@ void MapNode::serializeBulk(std::ostream &os, int version,
const MapNode *nodes, u32 nodecount, const MapNode *nodes, u32 nodecount,
u8 content_width, u8 params_width, bool compressed) u8 content_width, u8 params_width, bool compressed)
{ {
if(!ser_ver_supported(version)) if (!ser_ver_supported(version))
throw VersionMismatchException("ERROR: MapNode format not supported"); throw VersionMismatchException("ERROR: MapNode format not supported");
sanity_check(content_width == 2); sanity_check(content_width == 2);
@ -666,38 +666,33 @@ void MapNode::serializeBulk(std::ostream &os, int version,
// Can't do this anymore; we have 16-bit dynamically allocated node IDs // Can't do this anymore; we have 16-bit dynamically allocated node IDs
// in memory; conversion just won't work in this direction. // in memory; conversion just won't work in this direction.
if(version < 24) if (version < 24)
throw SerializationError("MapNode::serializeBulk: serialization to " throw SerializationError("MapNode::serializeBulk: serialization to "
"version < 24 not possible"); "version < 24 not possible");
SharedBuffer<u8> databuf(nodecount * (content_width + params_width)); size_t databuf_size = nodecount * (content_width + params_width);
u8 *databuf = new u8[databuf_size];
u32 start1 = content_width * nodecount;
u32 start2 = (content_width + 1) * nodecount;
// Serialize content // Serialize content
for(u32 i=0; i<nodecount; i++) for (u32 i = 0; i < nodecount; i++) {
writeU16(&databuf[i*2], nodes[i].param0); writeU16(&databuf[i * 2], nodes[i].param0);
// Serialize param1
u32 start1 = content_width * nodecount;
for(u32 i=0; i<nodecount; i++)
writeU8(&databuf[start1 + i], nodes[i].param1); writeU8(&databuf[start1 + i], nodes[i].param1);
// Serialize param2
u32 start2 = (content_width + 1) * nodecount;
for(u32 i=0; i<nodecount; i++)
writeU8(&databuf[start2 + i], nodes[i].param2); writeU8(&databuf[start2 + i], nodes[i].param2);
}
/* /*
Compress data to output stream Compress data to output stream
*/ */
if(compressed) if (compressed)
{ compressZlib(databuf, databuf_size, os);
compressZlib(databuf, os);
}
else else
{ os.write((const char*) &databuf[0], databuf_size);
os.write((const char*) &databuf[0], databuf.getSize());
} delete [] databuf;
} }
// Deserialize bulk node data // Deserialize bulk node data

11
src/serialization.cpp
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@ -53,7 +53,7 @@ void zerr(int ret)
} }
} }
void compressZlib(SharedBuffer<u8> data, std::ostream &os, int level) void compressZlib(const u8 *data, size_t data_size, std::ostream &os, int level)
{ {
z_stream z; z_stream z;
const s32 bufsize = 16384; const s32 bufsize = 16384;
@ -71,7 +71,7 @@ void compressZlib(SharedBuffer<u8> data, std::ostream &os, int level)
// Point zlib to our input buffer // Point zlib to our input buffer
z.next_in = (Bytef*)&data[0]; z.next_in = (Bytef*)&data[0];
z.avail_in = data.getSize(); z.avail_in = data_size;
// And get all output // And get all output
for(;;) for(;;)
{ {
@ -98,8 +98,7 @@ void compressZlib(SharedBuffer<u8> data, std::ostream &os, int level)
void compressZlib(const std::string &data, std::ostream &os, int level) void compressZlib(const std::string &data, std::ostream &os, int level)
{ {
SharedBuffer<u8> databuf((u8*)data.c_str(), data.size()); compressZlib((u8*)data.c_str(), data.size(), os, level);
compressZlib(databuf, os, level);
} }
void decompressZlib(std::istream &is, std::ostream &os) void decompressZlib(std::istream &is, std::ostream &os)
@ -186,11 +185,11 @@ void decompressZlib(std::istream &is, std::ostream &os)
inflateEnd(&z); inflateEnd(&z);
} }
void compress(SharedBuffer<u8> data, std::ostream &os, u8 version) void compress(const SharedBuffer<u8> &data, std::ostream &os, u8 version)
{ {
if(version >= 11) if(version >= 11)
{ {
compressZlib(data, os); compressZlib(*data ,data.getSize(), os);
return; return;
} }

4
src/serialization.h
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@ -86,12 +86,12 @@ inline bool ser_ver_supported(s32 v) {
Misc. serialization functions Misc. serialization functions
*/ */
void compressZlib(SharedBuffer<u8> data, std::ostream &os, int level = -1); void compressZlib(const u8 *data, size_t data_size, std::ostream &os, int level = -1);
void compressZlib(const std::string &data, std::ostream &os, int level = -1); void compressZlib(const std::string &data, std::ostream &os, int level = -1);
void decompressZlib(std::istream &is, std::ostream &os); void decompressZlib(std::istream &is, std::ostream &os);
// These choose between zlib and a self-made one according to version // These choose between zlib and a self-made one according to version
void compress(SharedBuffer<u8> data, std::ostream &os, u8 version); void compress(const SharedBuffer<u8> &data, std::ostream &os, u8 version);
//void compress(const std::string &data, std::ostream &os, u8 version); //void compress(const std::string &data, std::ostream &os, u8 version);
void decompress(std::istream &is, std::ostream &os, u8 version); void decompress(std::istream &is, std::ostream &os, u8 version);