mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-11-18 05:32:52 +00:00
141 lines
3.0 KiB
C++
141 lines
3.0 KiB
C++
#pragma once
|
|
|
|
#include <unistd.h>
|
|
#include <errno.h>
|
|
|
|
#include <DB/Common/Exception.h>
|
|
#include <DB/Common/ProfileEvents.h>
|
|
#include <DB/Common/CurrentMetrics.h>
|
|
|
|
#include <DB/IO/WriteBufferFromFileBase.h>
|
|
#include <DB/IO/WriteBuffer.h>
|
|
#include <DB/IO/WriteHelpers.h>
|
|
#include <DB/IO/BufferWithOwnMemory.h>
|
|
|
|
|
|
namespace ProfileEvents
|
|
{
|
|
extern const Event WriteBufferFromFileDescriptorWrite;
|
|
extern const Event WriteBufferFromFileDescriptorWriteBytes;
|
|
}
|
|
|
|
namespace CurrentMetrics
|
|
{
|
|
extern const Metric Write;
|
|
}
|
|
|
|
namespace DB
|
|
{
|
|
|
|
namespace ErrorCodes
|
|
{
|
|
extern const int CANNOT_WRITE_TO_FILE_DESCRIPTOR;
|
|
extern const int CANNOT_FSYNC;
|
|
extern const int CANNOT_SEEK_THROUGH_FILE;
|
|
extern const int CANNOT_TRUNCATE_FILE;
|
|
}
|
|
|
|
/** Use ready file descriptor. Does not open or close a file.
|
|
*/
|
|
class WriteBufferFromFileDescriptor : public WriteBufferFromFileBase
|
|
{
|
|
protected:
|
|
int fd;
|
|
|
|
void nextImpl() override
|
|
{
|
|
if (!offset())
|
|
return;
|
|
|
|
size_t bytes_written = 0;
|
|
while (bytes_written != offset())
|
|
{
|
|
ProfileEvents::increment(ProfileEvents::WriteBufferFromFileDescriptorWrite);
|
|
|
|
ssize_t res = 0;
|
|
{
|
|
CurrentMetrics::Increment metric_increment{CurrentMetrics::Write};
|
|
res = ::write(fd, working_buffer.begin() + bytes_written, offset() - bytes_written);
|
|
}
|
|
|
|
if ((-1 == res || 0 == res) && errno != EINTR)
|
|
throwFromErrno("Cannot write to file " + getFileName(), ErrorCodes::CANNOT_WRITE_TO_FILE_DESCRIPTOR);
|
|
|
|
if (res > 0)
|
|
bytes_written += res;
|
|
}
|
|
|
|
ProfileEvents::increment(ProfileEvents::WriteBufferFromFileDescriptorWriteBytes, bytes_written);
|
|
}
|
|
|
|
/// Name or some description of file.
|
|
virtual std::string getFileName() const override
|
|
{
|
|
return "(fd = " + toString(fd) + ")";
|
|
}
|
|
|
|
public:
|
|
WriteBufferFromFileDescriptor(int fd_ = -1, size_t buf_size = DBMS_DEFAULT_BUFFER_SIZE, char * existing_memory = nullptr, size_t alignment = 0)
|
|
: WriteBufferFromFileBase(buf_size, existing_memory, alignment), fd(fd_) {}
|
|
|
|
/** Could be used before initialization if needed 'fd' was not passed to constructor.
|
|
* It's not possible to change 'fd' during work.
|
|
*/
|
|
void setFD(int fd_)
|
|
{
|
|
fd = fd_;
|
|
}
|
|
|
|
~WriteBufferFromFileDescriptor()
|
|
{
|
|
try
|
|
{
|
|
if (fd >= 0)
|
|
next();
|
|
}
|
|
catch (...)
|
|
{
|
|
tryLogCurrentException(__PRETTY_FUNCTION__);
|
|
}
|
|
}
|
|
|
|
int getFD() const override
|
|
{
|
|
return fd;
|
|
}
|
|
|
|
off_t getPositionInFile() override
|
|
{
|
|
return seek(0, SEEK_CUR);
|
|
}
|
|
|
|
void sync() override
|
|
{
|
|
/// If buffer has pending data - write it.
|
|
next();
|
|
|
|
/// Request OS to sync data with storage medium.
|
|
int res = fsync(fd);
|
|
if (-1 == res)
|
|
throwFromErrno("Cannot fsync " + getFileName(), ErrorCodes::CANNOT_FSYNC);
|
|
}
|
|
|
|
private:
|
|
off_t doSeek(off_t offset, int whence) override
|
|
{
|
|
off_t res = lseek(fd, offset, whence);
|
|
if (-1 == res)
|
|
throwFromErrno("Cannot seek through file " + getFileName(), ErrorCodes::CANNOT_SEEK_THROUGH_FILE);
|
|
return res;
|
|
}
|
|
|
|
void doTruncate(off_t length) override
|
|
{
|
|
int res = ftruncate(fd, length);
|
|
if (-1 == res)
|
|
throwFromErrno("Cannot truncate file " + getFileName(), ErrorCodes::CANNOT_TRUNCATE_FILE);
|
|
}
|
|
};
|
|
|
|
}
|