dbms: Server: feature development. [#METR-15090]

dbms/include/DB/IO/ReadBuffer.h

@@ -44,7 +44,7 @@ public:
 	{
 		bytes += offset();
 		bool res = nextImpl();
-		(void) sync();
+		sync();
 		if (!res)
 			working_buffer.resize(0);
 
@@ -150,7 +150,7 @@ private:
 	  * Кинуть исключение, если что-то не так.
 	  */
 	virtual bool nextImpl() { return false; };
-	virtual bool sync() { return false; }
+	virtual void sync() {}
 };
 
 

dbms/include/DB/IO/ReadBufferAIO.h

@@ -28,15 +28,15 @@ public:
 	ReadBufferAIO & operator=(const ReadBufferAIO &) = delete;
 
 	void setMaxBytes(size_t max_bytes_read_);
-	off_t seek(off_t off, int whence = SEEK_SET) override;
 	off_t getPositionInFile() override;
 	std::string getFileName() const noexcept override { return filename; }
 	int getFD() const noexcept override { return fd; }
 
 private:
 	off_t getPositionInFileRelaxed() const noexcept;
+	off_t doSeek(off_t off, int whence) override;
 	bool nextImpl() override;
-	bool sync() override;
+	void sync() override;
 	/// Ждать окончания текущей асинхронной задачи.
 	void waitForAIOCompletion();
 	/// Менять местами основной и дублирующий буферы.

dbms/include/DB/IO/ReadBufferFromFileBase.h

@@ -12,16 +12,15 @@ namespace DB
 class ReadBufferFromFileBase : public BufferWithOwnMemory<ReadBuffer>
 {
 public:
-	ReadBufferFromFileBase(size_t buf_size, char * existing_memory, size_t alignment)
-	: BufferWithOwnMemory<ReadBuffer>(buf_size, existing_memory, alignment)
-	{
-	}
-
-	virtual ~ReadBufferFromFileBase() {}
-	virtual off_t seek(off_t off, int whence) = 0;
+	ReadBufferFromFileBase(size_t buf_size, char * existing_memory, size_t alignment);
+	virtual ~ReadBufferFromFileBase();
+	off_t seek(off_t off, int whence = SEEK_SET);
 	virtual off_t getPositionInFile() = 0;
 	virtual std::string getFileName() const noexcept = 0;
 	virtual int getFD() const noexcept = 0;
+
+protected:
+	virtual off_t doSeek(off_t off, int whence) = 0;
 };
 
 }

dbms/include/DB/IO/ReadBufferFromFileDescriptor.h

@@ -68,8 +68,14 @@ public:
 		return fd;
 	}
 
+	off_t getPositionInFile() override
+	{
+		return pos_in_file - (working_buffer.end() - pos);
+	}
+
+private:
 	/// Если offset такой маленький, что мы не выйдем за пределы буфера, настоящий seek по файлу не делается.
-	off_t seek(off_t offset, int whence = SEEK_SET) override
+	off_t doSeek(off_t offset, int whence) override
 	{
 		off_t new_pos = offset;
 		if (whence == SEEK_CUR)
@@ -99,11 +105,6 @@ public:
 			return res;
 		}
 	}
-
-	off_t getPositionInFile() override
-	{
-		return pos_in_file - (working_buffer.end() - pos);
-	}
 };
 
 }

dbms/include/DB/IO/WriteBufferAIO.h

@@ -26,7 +26,6 @@ public:
 	WriteBufferAIO(const WriteBufferAIO &) = delete;
 	WriteBufferAIO & operator=(const WriteBufferAIO &) = delete;
 
-	off_t seek(off_t off, int whence = SEEK_SET) override;
 	off_t getPositionInFile() override;
 	void truncate(off_t length = 0) override;
 	void sync() override;
@@ -34,6 +33,8 @@ public:
 	int getFD() const noexcept override { return fd; }
 
 private:
+	///
+	off_t doSeek(off_t off, int whence) override;
 	/// Если в буфере ещё остались данные - запишем их.
 	void flush();
 	///

dbms/include/DB/IO/WriteBufferFromFileBase.h

@@ -12,18 +12,17 @@ namespace DB
 class WriteBufferFromFileBase : public BufferWithOwnMemory<WriteBuffer>
 {
 public:
-	WriteBufferFromFileBase(size_t buf_size, char * existing_memory, size_t alignment)
-	: BufferWithOwnMemory<WriteBuffer>(buf_size, existing_memory, alignment)
-	{
-	}
-
-	virtual ~WriteBufferFromFileBase() {}
-	virtual off_t seek(off_t off, int whence) = 0;
+	WriteBufferFromFileBase(size_t buf_size, char * existing_memory, size_t alignment);
+	virtual ~WriteBufferFromFileBase();
+	off_t seek(off_t off, int whence = SEEK_SET);
 	virtual off_t getPositionInFile() = 0;
 	virtual void truncate(off_t length) = 0;
 	virtual void sync() = 0;
 	virtual std::string getFileName() const noexcept = 0;
 	virtual int getFD() const noexcept = 0;
+
+protected:
+	virtual off_t doSeek(off_t off, int whence) = 0;
 };
 
 }

dbms/include/DB/IO/WriteBufferFromFileDescriptor.h

@@ -75,14 +75,6 @@ public:
 		return fd;
 	}
 
-	off_t seek(off_t offset, int whence = SEEK_SET) override
-	{
-		off_t res = lseek(fd, offset, whence);
-		if (-1 == res)
-			throwFromErrno("Cannot seek through file " + getFileName(), ErrorCodes::CANNOT_SEEK_THROUGH_FILE);
-		return res;
-	}
-
 	off_t getPositionInFile() override
 	{
 		return seek(0, SEEK_CUR);
@@ -105,6 +97,15 @@ public:
 		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;
+	}
 };
 
 }

dbms/src/IO/ReadBufferAIO.cpp

@@ -37,7 +37,7 @@ ReadBufferAIO::~ReadBufferAIO()
 	{
 		try
 		{
-			(void) sync();
+			sync();
 		}
 		catch (...)
 		{
@@ -59,9 +59,9 @@ void ReadBufferAIO::setMaxBytes(size_t max_bytes_read_)
 	max_bytes_read = max_bytes_read_;
 }
 
-off_t ReadBufferAIO::seek(off_t off, int whence)
+off_t ReadBufferAIO::doSeek(off_t off, int whence)
 {
-	(void) sync();
+	sync();
 
 	off_t new_pos;
 
@@ -132,7 +132,7 @@ bool ReadBufferAIO::nextImpl()
 	if (is_eof)
 		return false;
 
-	(void) sync();
+	sync();
 	is_started = true;
 
 	/// Если конец файла только что достигнут, больше ничего не делаем.
@@ -202,19 +202,13 @@ bool ReadBufferAIO::nextImpl()
 	return true;
 }
 
-bool ReadBufferAIO::sync()
+void ReadBufferAIO::sync()
 {
-	if (is_eof)
-		return false;
-	if (!is_started)
-		return false;
-	if (!is_pending_read)
-		return false;
+	if (is_eof || !is_started || !is_pending_read)
+		return;
 
 	waitForAIOCompletion();
 	swapBuffers();
-
-	return true;
 }
 
 void ReadBufferAIO::waitForAIOCompletion()

dbms/src/IO/ReadBufferFromFileBase.cpp

@@ -0,0 +1,20 @@
+#include <DB/IO/ReadBufferFromFileBase.h>
+
+namespace DB
+{
+
+ReadBufferFromFileBase::ReadBufferFromFileBase(size_t buf_size, char * existing_memory, size_t alignment)
+	: BufferWithOwnMemory<ReadBuffer>(buf_size, existing_memory, alignment)
+{
+}
+
+ReadBufferFromFileBase::~ReadBufferFromFileBase()
+{
+}
+
+off_t ReadBufferFromFileBase::seek(off_t off, int whence)
+{
+	return doSeek(off, whence);
+}
+
+}

dbms/src/IO/WriteBufferAIO.cpp

@@ -61,7 +61,7 @@ WriteBufferAIO::~WriteBufferAIO()
 		::close(fd2);
 }
 
-off_t WriteBufferAIO::seek(off_t off, int whence)
+off_t WriteBufferAIO::doSeek(off_t off, int whence)
 {
 	flush();
 

dbms/src/IO/WriteBufferFromFileBase.cpp

@@ -0,0 +1,20 @@
+#include <DB/IO/WriteBufferFromFileBase.h>
+
+namespace DB
+{
+
+WriteBufferFromFileBase::WriteBufferFromFileBase(size_t buf_size, char * existing_memory, size_t alignment)
+	: BufferWithOwnMemory<WriteBuffer>(buf_size, existing_memory, alignment)
+{
+}
+
+WriteBufferFromFileBase::~WriteBufferFromFileBase()
+{
+}
+
+off_t WriteBufferFromFileBase::seek(off_t off, int whence)
+{
+	return doSeek(off, whence);
+}
+
+}