ClickHouse/dbms/src/IO/WriteBufferFromOStream.h

58 lines
1.1 KiB
C++

#pragma once
#include <iostream>
#include <Common/Exception.h>
#include <IO/WriteBuffer.h>
#include <IO/BufferWithOwnMemory.h>
namespace DB
{
namespace ErrorCodes
{
extern const int CANNOT_WRITE_TO_OSTREAM;
}
class WriteBufferFromOStream : public BufferWithOwnMemory<WriteBuffer>
{
private:
std::ostream & ostr;
void nextImpl() override
{
if (!offset())
return;
ostr.write(working_buffer.begin(), offset());
ostr.flush();
if (!ostr.good())
throw Exception("Cannot write to ostream", ErrorCodes::CANNOT_WRITE_TO_OSTREAM);
}
public:
WriteBufferFromOStream(
std::ostream & ostr_,
size_t size = DBMS_DEFAULT_BUFFER_SIZE,
char * existing_memory = nullptr,
size_t alignment = 0)
: BufferWithOwnMemory<WriteBuffer>(size, existing_memory, alignment), ostr(ostr_) {}
~WriteBufferFromOStream() override
{
try
{
next();
}
catch (...)
{
tryLogCurrentException(__PRETTY_FUNCTION__);
}
}
};
}