DB: unified compressed buffers and compressed iostreams [#CONV-2546].

This commit is contained in:
Alexey Milovidov 2011-06-27 18:33:23 +00:00
parent ea1a7d9192
commit a6ec731e4c
5 changed files with 27 additions and 7 deletions

View File

@ -19,7 +19,7 @@ class BufferWithOwnMemory : public Base
protected:
std::vector<char> memory;
public:
BufferWithOwnMemory(size_t size = DBMS_DEFAULT_BUFFER_SIZE) : Base(NULL, size), memory(size)
BufferWithOwnMemory(size_t size = DBMS_DEFAULT_BUFFER_SIZE) : Base(NULL, 0), memory(size)
{
Base::set(&memory[0], size);
}

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@ -13,9 +13,6 @@
#include <DB/IO/CompressedStream.h>
#define DBMS_COMPRESSED_READ_BUFFER_MAX_COMPRESSED_SIZE 0x40000000ULL /// 1GB
namespace DB
{
@ -38,7 +35,7 @@ private:
in.readStrict(&compressed_buffer[0], QUICKLZ_HEADER_SIZE);
size_t size_compressed = qlz_size_compressed(&compressed_buffer[0]);
if (size_compressed > DBMS_COMPRESSED_READ_BUFFER_MAX_COMPRESSED_SIZE)
if (size_compressed > DBMS_MAX_COMPRESSED_SIZE)
throw Exception("Too large size_compressed. Most likely corrupted data.", ErrorCodes::TOO_LARGE_SIZE_COMPRESSED);
size_t size_decompressed = qlz_size_decompressed(&compressed_buffer[0]);

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@ -3,6 +3,7 @@
/** Общие для CompressingStream.h и DecompressingStream.h дефайны */
#define DBMS_MAX_COMPRESSED_SIZE 0x40000000ULL /// 1GB
#define DBMS_STREAM_BUFFER_SIZE 4096
#define DBMS_COMPRESSING_STREAM_BUFFER_SIZE 1048576
#define QUICKLZ_ADDITIONAL_SPACE 400

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@ -1,7 +1,10 @@
#include <algorithm>
#include <city.h>
#include <quicklz/quicklz_level1.h>
#include <DB/Core/ErrorCodes.h>
#include <DB/Core/Exception.h>
#include <DB/IO/CompressedInputStream.h>
@ -30,13 +33,25 @@ void DecompressingStreamBuf::getChunk(std::vector<char> & res)
void DecompressingStreamBuf::readCompressedChunk()
{
/// прочитаем чексумму
uint128 checksum;
p_istr->read(reinterpret_cast<char *>(&checksum), sizeof(checksum));
if (p_istr->eof())
return;
if (!p_istr->good())
throw Exception("Cannot read all data.", ErrorCodes::CANNOT_READ_ALL_DATA);
/// прочитаем заголовок
p_istr->read(&compressed_buffer[0], QUICKLZ_HEADER_SIZE);
if (!p_istr->good())
return;
throw Exception("Cannot read all data.", ErrorCodes::CANNOT_READ_ALL_DATA);
size_t size_compressed = qlz_size_compressed(&compressed_buffer[0]);
if (size_compressed > DBMS_MAX_COMPRESSED_SIZE)
throw Exception("Too large size_compressed. Most likely corrupted data.", ErrorCodes::TOO_LARGE_SIZE_COMPRESSED);
size_t size_decompressed = qlz_size_decompressed(&compressed_buffer[0]);
compressed_buffer.resize(size_compressed);
@ -47,7 +62,10 @@ void DecompressingStreamBuf::readCompressedChunk()
p_istr->read(&compressed_buffer[QUICKLZ_HEADER_SIZE], size_compressed - QUICKLZ_HEADER_SIZE);
if (!p_istr->good())
return;
throw Exception("Cannot read all data.", ErrorCodes::CANNOT_READ_ALL_DATA);
if (checksum != CityHash128(&compressed_buffer[0], size_compressed))
throw Exception("Checksum doesnt match: corrupted data.", ErrorCodes::CHECKSUM_DOESNT_MATCH);
/// разжимаем блок
qlz_decompress(&compressed_buffer[0], &uncompressed_buffer[0], &scratch[0]);

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@ -1,5 +1,7 @@
#include <algorithm>
#include <city.h>
#include <DB/IO/CompressedOutputStream.h>
@ -40,6 +42,8 @@ int CompressingStreamBuf::writeToDevice(const char * buffer, std::streamsize len
length,
&scratch[0]);
uint128 checksum = CityHash128(&compressed_buffer[0], compressed_size);
p_ostr->write(reinterpret_cast<const char *>(&checksum), sizeof(checksum));
p_ostr->write(&compressed_buffer[0], compressed_size);
return static_cast<int>(length);
}