class Falcon::Adapters::Input

This implementation is not always rewindable, to avoid buffering the input when handling large uploads. See {Rewindable} for more details.
The input stream is an ‘IO`-like object which contains the raw HTTP POST data. When applicable, its external encoding must be `ASCII-8BIT` and it must be opened in binary mode, for Ruby 1.9 compatibility. The input stream must respond to `gets`, `each`, `read` and `rewind`.
Wraps a streaming input body into the interface required by `rack.input`.

def close

Close and discard the remainder of the input stream.
def close
	@body&.close
end

def each(&block)

@parameter chunk [String]
@yields {|chunk| ...}
Enumerate chunks of the request body.
def each(&block)
	return to_enum unless block_given?
	
	while chunk = gets
		yield chunk
	end
end

def eof?

@returns [Boolean]
Has the input stream been read completely?
def eof?
	@finished and @buffer.nil?
end

def gets

@returns [String | Nil] The next chunk from the body.

`gets` must be called without arguments and return a `String`, or `nil` when the input stream has no more data.

Read the next chunk of data from the input stream.
def gets
	if @buffer.nil?
		return read_next
	else
		buffer = @buffer
		@buffer = nil
		return buffer
	end
end

def initialize(body)

@parameter body [Protocol::HTTP::Body::Readable]
Initialize the input wrapper.
def initialize(body)
	@body = body
	
	# Will hold remaining data in `#read`.
	@buffer = nil
	@finished = @body.nil?
end

def read(length = nil, buffer = nil)

@returns a buffer containing the data
@parameter buffer [String] the buffer which will receive the data
@parameter length [Integer] the amount of data to read

`read` behaves like `IO#read`. Its signature is `read(length = nil, buffer = nil)`. If given, length must be a non-negative `Integer` (>= 0) or `nil`, and buffer must be a `String` and may not be nil. If `length` is given and not `nil`, then this method reads at most `length` bytes from the input stream. If `length` is not given or `nil`, then this method reads all data. When the end is reached, this method returns `nil` if `length` is given and not `nil`, or an empty `String` if `length` is not given or is `nil`. If `buffer` is given, then the read data will be placed into the `buffer` instead of a newly created `String` object.

Read data from the input stream.
def read(length = nil, buffer = nil)
	buffer ||= Async::IO::Buffer.new
	buffer.clear
	
	until buffer.bytesize == length
		@buffer = read_next if @buffer.nil?
		break if @buffer.nil?
		
		remaining_length = length - buffer.bytesize if length
		
		if remaining_length && remaining_length < @buffer.bytesize
			# We know that we are not going to reuse the original buffer.
			# But byteslice will generate a hidden copy. So let's freeze it first:
			@buffer.freeze
			
			buffer << @buffer.byteslice(0, remaining_length)
			@buffer = @buffer.byteslice(remaining_length, @buffer.bytesize)
		else
			buffer << @buffer
			@buffer = nil
		end
	end
	
	return nil if buffer.empty? && length && length > 0
	
	return buffer
end

def read_next

def read_next
	return nil if @finished
	
	if chunk = @body.read
		return chunk
	else
		@finished = true
		return nil
	end
end

def rewind

@returns [Boolean] Whether the body could be rewound.

`rewind` must be called without arguments. It rewinds the input stream back to the beginning. It must not raise Errno::ESPIPE: that is, it may not be a pipe or a socket. Therefore, handler developers must buffer the input data into some rewindable object if the underlying input stream is not rewindable.

Rewind the input stream back to the start.
def rewind
	if @body and @body.respond_to? :rewind
		# If the body is not rewindable, this will fail.
		@body.rewind
		@buffer = nil
		@finished = false
		
		return true
	end
	
	return false
end