Class: IO::Stream::Generic
- Inherits:
-
Object
- Object
- IO::Stream::Generic
- Defined in:
- lib/io/stream/generic.rb
Direct Known Subclasses
Instance Attribute Summary collapse
-
#block_size ⇒ Object
Returns the value of attribute block_size.
Instance Method Summary collapse
-
#<<(string) ⇒ Object
Writes ‘string` to the stream and returns self.
-
#close ⇒ Object
Best effort to flush any unwritten data, and then close the underling IO.
- #close_read ⇒ Object
- #close_write ⇒ Object
- #closed? ⇒ Boolean
- #eof! ⇒ Object
-
#eof? ⇒ Boolean
Determins if the stream has consumed all available data.
-
#flush ⇒ Object
Flushes buffered data to the stream.
- #gets(separator = $/, **options) ⇒ Object
-
#initialize(block_size: BLOCK_SIZE, maximum_read_size: MAXIMUM_READ_SIZE) ⇒ Generic
constructor
A new instance of Generic.
- #peek(size = nil) ⇒ Object
- #puts(*arguments, separator: $/) ⇒ Object
-
#read(size = nil) ⇒ Object
Reads ‘size` bytes from the stream.
- #read_exactly(size, exception: EOFError) ⇒ Object
-
#read_partial(size = nil) ⇒ Object
Read at most ‘size` bytes from the stream.
-
#read_until(pattern, offset = 0, chomp: true) ⇒ String
Efficiently read data from the stream until encountering pattern.
-
#readable? ⇒ Boolean
Whether there is a chance that a read operation will succeed or not.
-
#readpartial(size = nil) ⇒ Object
This is a compatibility shim for existing code that uses ‘readpartial`.
-
#write(string) ⇒ Object
Writes ‘string` to the buffer.
Constructor Details
#initialize(block_size: BLOCK_SIZE, maximum_read_size: MAXIMUM_READ_SIZE) ⇒ Generic
Returns a new instance of Generic.
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# File 'lib/io/stream/generic.rb', line 22 def initialize(block_size: BLOCK_SIZE, maximum_read_size: MAXIMUM_READ_SIZE) @eof = false @writing = ::Thread::Mutex.new @block_size = block_size @maximum_read_size = maximum_read_size @read_buffer = StringBuffer.new @write_buffer = StringBuffer.new @drain_buffer = StringBuffer.new # Used as destination buffer for underlying reads. @input_buffer = StringBuffer.new end |
Instance Attribute Details
#block_size ⇒ Object
Returns the value of attribute block_size.
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# File 'lib/io/stream/generic.rb', line 38 def block_size @block_size end |
Instance Method Details
#<<(string) ⇒ Object
Writes ‘string` to the stream and returns self.
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# File 'lib/io/stream/generic.rb', line 164 def <<(string) write(string) return self end |
#close ⇒ Object
Best effort to flush any unwritten data, and then close the underling IO.
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# File 'lib/io/stream/generic.rb', line 190 def close return if closed? begin flush rescue # We really can't do anything here unless we want #close to raise exceptions. ensure sysclose end end |
#close_read ⇒ Object
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# File 'lib/io/stream/generic.rb', line 182 def close_read end |
#close_write ⇒ Object
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# File 'lib/io/stream/generic.rb', line 185 def close_write flush end |
#closed? ⇒ Boolean
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# File 'lib/io/stream/generic.rb', line 178 def closed? false end |
#eof! ⇒ Object
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# File 'lib/io/stream/generic.rb', line 216 def eof! @read_buffer.clear @eof = true raise EOFError end |
#eof? ⇒ Boolean
Determins if the stream has consumed all available data. May block if the stream is not readable. See #readable? for a non-blocking alternative.
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# File 'lib/io/stream/generic.rb', line 206 def eof? if !@read_buffer.empty? return false elsif @eof return true else return !self.fill_read_buffer end end |
#flush ⇒ Object
Flushes buffered data to the stream.
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# File 'lib/io/stream/generic.rb', line 133 def flush return if @write_buffer.empty? @writing.synchronize do # Flip the write buffer and drain buffer: @write_buffer, @drain_buffer = @drain_buffer, @write_buffer begin syswrite(@drain_buffer) ensure # If the write operation fails, we still need to clear this buffer, and the data is essentially lost. @drain_buffer.clear end end end |
#gets(separator = $/, **options) ⇒ Object
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# File 'lib/io/stream/generic.rb', line 128 def gets(separator = $/, **) read_until(separator, **) end |
#peek(size = nil) ⇒ Object
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# File 'lib/io/stream/generic.rb', line 111 def peek(size = nil) if size until @eof or @read_buffer.bytesize >= size # Compute the amount of data we need to read from the underlying stream: read_size = size - @read_buffer.bytesize # Don't read less than @block_size to avoid lots of small reads: fill_read_buffer(read_size > @block_size ? read_size : @block_size) end return @read_buffer[..([size, @read_buffer.size].min - 1)] end until (block_given? && yield(@read_buffer)) or @eof fill_read_buffer end return @read_buffer end |
#puts(*arguments, separator: $/) ⇒ Object
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# File 'lib/io/stream/generic.rb', line 170 def puts(*arguments, separator: $/) arguments.each do |argument| @write_buffer << argument << 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/io/stream/generic.rb', line 41 def read(size = nil) return String.new(encoding: Encoding::BINARY) if size == 0 if size until @eof or @read_buffer.bytesize >= size # Compute the amount of data we need to read from the underlying stream: read_size = size - @read_buffer.bytesize # Don't read less than @block_size to avoid lots of small reads: fill_read_buffer(read_size > @block_size ? read_size : @block_size) end else until @eof fill_read_buffer end end return consume_read_buffer(size) end |
#read_exactly(size, exception: EOFError) ⇒ Object
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# File 'lib/io/stream/generic.rb', line 72 def read_exactly(size, exception: EOFError) if buffer = read(size) if buffer.bytesize != size raise exception, "could not read enough data" end return buffer end raise exception, "encountered eof while reading data" end |
#read_partial(size = nil) ⇒ Object
Read at most ‘size` bytes from the stream. Will avoid reading from the underlying stream if possible.
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# File 'lib/io/stream/generic.rb', line 62 def read_partial(size = nil) return String.new(encoding: Encoding::BINARY) if size == 0 if !@eof and @read_buffer.empty? fill_read_buffer end return consume_read_buffer(size) end |
#read_until(pattern, offset = 0, chomp: true) ⇒ String
Efficiently read data from the stream until encountering pattern.
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# File 'lib/io/stream/generic.rb', line 92 def read_until(pattern, offset = 0, chomp: true) # We don't want to split on the pattern, so we subtract the size of the pattern. split_offset = pattern.bytesize - 1 until index = @read_buffer.index(pattern, offset) offset = @read_buffer.bytesize - split_offset offset = 0 if offset < 0 return unless fill_read_buffer end @read_buffer.freeze matched = @read_buffer.byteslice(0, index+(chomp ? 0 : pattern.bytesize)) @read_buffer = @read_buffer.byteslice(index+pattern.bytesize, @read_buffer.bytesize) return matched end |
#readable? ⇒ Boolean
Whether there is a chance that a read operation will succeed or not.
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# File 'lib/io/stream/generic.rb', line 225 def readable? # If we are at the end of the file, we can't read any more data: if @eof return false end # If the read buffer is not empty, we can read more data: if !@read_buffer.empty? return true end # If the underlying stream is readable, we can read more data: return !closed? end |
#readpartial(size = nil) ⇒ Object
This is a compatibility shim for existing code that uses ‘readpartial`.
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# File 'lib/io/stream/generic.rb', line 85 def readpartial(size = nil) read_partial(size) or raise EOFError, "Encountered eof while reading data!" 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`.
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# File 'lib/io/stream/generic.rb', line 153 def write(string) @write_buffer << string if @write_buffer.bytesize >= @block_size flush end return string.bytesize end |