Class: Async::IO::Stream

Inherits:
Object
  • Object
show all
Defined in:
lib/async/io/stream.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(io, block_size: 1024*8, sync: true) ⇒ Stream

Returns a new instance of Stream.



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# File 'lib/async/io/stream.rb', line 27

def initialize(io, block_size: 1024*8, sync: true)
	@io = io
	@eof = false
	
	# We don't want Ruby to do any IO buffering.
	@io.sync = sync
	
	@block_size = block_size
	
	@read_buffer = BinaryString.new
	@write_buffer = BinaryString.new
end

Instance Attribute Details

#io ⇒ Object (readonly)

Returns the value of attribute io.



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# File 'lib/async/io/stream.rb', line 40

def io
  @io
end

Instance Method Details

#<<(string) ⇒ Object

Writes ‘string` to the stream and returns self.



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# File 'lib/async/io/stream.rb', line 68

def <<(string)
	write(string)
	
	return self
end

#close ⇒ Object

Closes the stream and flushes any unwritten data.



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# File 'lib/async/io/stream.rb', line 95

def close
	flush rescue nil
	
	@io.close
end

#eof? ⇒ Boolean Also known as: eof

Returns true if the stream is at file which means there is no more data to be read.

Returns:

  • (Boolean) 


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# File 'lib/async/io/stream.rb', line 102

def eof?
	fill_read_buffer if !@eof && @read_buffer.empty?
	
	return @eof && @read_buffer.empty?
end

#flush ⇒ Object

Flushes buffered data to the stream.



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# File 'lib/async/io/stream.rb', line 75

def flush
	syswrite(@write_buffer)
	@write_buffer.clear
end

#gets(separator = $/) ⇒ Object 



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# File 'lib/async/io/stream.rb', line 80

def gets(separator = $/)
	flush
	
	read_until(separator)
end

#peek ⇒ Object 



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# File 'lib/async/io/stream.rb', line 132

def peek
	until yield(@read_buffer) || @eof
		fill_read_buffer
	end
end

#puts(*args, separator: $/) ⇒ Object 



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# File 'lib/async/io/stream.rb', line 86

def puts(*args, separator: $/)
	args.each do |arg|
		@write_buffer << arg << separator
	end
	
	flush
end

#read(size = nil) ⇒ Object

Reads ‘size` bytes from the stream. If size is not specified, read until end of file.



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# File 'lib/async/io/stream.rb', line 43

def read(size = nil)
	return "" if size == 0
	
	until @eof || (size && size <= @read_buffer.size)
		fill_read_buffer
	end

	return consume_read_buffer(size)
end

#read_until(pattern) ⇒ String

Efficiently read data from the stream until encountering pattern.

Parameters:

  • pattern (String) —

    The pattern to match.

Returns:

  • (String) —

    The contents of the stream up until the pattern, which is consumed but not returned.



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# File 'lib/async/io/stream.rb', line 113

def read_until(pattern)
	index = @read_buffer.index(pattern)
	
	until index
		offset = @read_buffer.size

		fill_read_buffer
		
		return if @eof

		index = @read_buffer.index(pattern, offset)
	end
	
	matched = @read_buffer.slice!(0, index)
	@read_buffer.slice!(0, pattern.bytesize)
	
	return matched
end

#write(string) ⇒ Object

Writes ‘string` to the buffer. When the buffer is full or #sync is true the buffer is flushed to the underlying `io`.

Parameters:

  • string —

    the string to write to the buffer.

Returns:

  • the number of bytes appended to the buffer.



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# File 'lib/async/io/stream.rb', line 57

def write(string)
	@write_buffer << string
	
	if @write_buffer.size > @block_size
		flush
	end
	
	return string.bytesize
end