Module: OpenSSL::Buffering

Relationships & Source Files
Extension / Inclusion / Inheritance Descendants
Included In: SSL::SSLSocket
Super Chains via Extension / Inclusion / Inheritance
Instance Chain: self, Enumerable
Defined in:	ext/openssl/lib/openssl/buffering.rb

Overview

::OpenSSL IO buffering mix-in module.

This module allows an SSL::SSLSocket to behave like an ::IO.

You typically won't use this module directly, you can see it implemented in SSL::SSLSocket.

Constant Summary

BLOCK_SIZE =

Default size to read from or write to the SSLSocket for buffer operations.

# File 'ext/openssl/lib/openssl/buffering.rb', line 35
```
1024*16
```

Instance Attribute Summary

#eof readonly

Alias for #eof?.
#sync rw

The “sync mode” of the SSLSocket.

Instance Method Summary

#<<(s)

Writes s to the stream.
#close

Closes the SSLSocket and flushes any unwritten data.
#each(eol = $/) (also: #each_line)

Executes the block for every line in the stream where lines are separated by eol.
#each_byte

Calls the given block once for each byte in the stream.
#each_line(eol = $/)

Alias for #each.
#eof? ⇒ Boolean (also: #eof) readonly

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

Flushes buffered data to the SSLSocket.
#getc

Reads one character from the stream.
#gets(eol = $/, limit = nil)

Reads the next “line” from the stream.
#initialize

Creates an instance of OpenSSL's buffering ::IO module.
#print(*args)

Writes args to the stream.
#printf(s, *args)

Formats and writes to the stream converting parameters under control of the format string.
#puts(*args)

Writes args to the stream along with a record separator.
#read(size = nil, buf = nil)

Reads size bytes from the stream.
#read_nonblock(maxlen, buf = nil, exception: true)

Reads at most maxlen bytes in the non-blocking manner.
#readchar

Reads a one-character string from the stream.
#readline(eol = $/)

Reads a line from the stream which is separated by eol.
#readlines(eol = $/)

Reads lines from the stream which are separated by eol.
#readpartial(maxlen, buf = nil)

Reads at most maxlen bytes from the stream.
#ungetc(c)

Pushes character c back onto the stream such that a subsequent buffered character read will return it.
#write(*s)

Writes s to the stream.
#write_nonblock(s, exception: true)

Writes s in the non-blocking manner.
#consume_rbuff(size = nil) private

Consumes size bytes from the buffer.
#do_write(s) private

Writes s to the buffer.
#fill_rbuff private

Fills the buffer from the underlying SSLSocket.

Instance Attribute Details

#eof (readonly)

Alias for #eof?.

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 303


alias eof eof?

#sync (rw)

The “sync mode” of the SSLSocket.

See IO#sync for full details.

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 30


attr_accessor :sync

Instance Method Details

#<<(s)

Writes s to the stream. s will be converted to a String using .to_s method.

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 395


def <<(s)
  do_write(s)
  self
end

#close

Closes the SSLSocket and flushes any unwritten data.

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 458


def close
  flush rescue nil
  sysclose
end

#consume_rbuff(size = nil) (private)

Consumes size bytes from the buffer

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 68


def consume_rbuff(size=nil)
  if @rbuffer.empty?
    nil
  else
    size = @rbuffer.size unless size
    ret = @rbuffer[0, size]
    @rbuffer[0, size] = ""
    ret
  end
end

#do_write(s) (private)

Writes s to the buffer. When the buffer is full or #sync is true the buffer is flushed to the underlying socket.

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 314


def do_write(s)
  @wbuffer = "" unless defined? @wbuffer
  @wbuffer << s
  @wbuffer.force_encoding(Encoding::BINARY)
  @sync ||= false
  if @sync or @wbuffer.size > BLOCK_SIZE or idx = @wbuffer.rindex($/)
    remain = idx ? idx + $/.size : @wbuffer.length
    nwritten = 0
    while remain > 0
      str = @wbuffer[nwritten,remain]
      begin
        nwrote = syswrite(str)
      rescue Errno::EAGAIN
        retry
      end
      remain -= nwrote
      nwritten += nwrote
    end
    @wbuffer[0,nwritten] = ""
  end
end

#each(eol = $/) Also known as: #each_line

Executes the block for every line in the stream where lines are separated by eol.

#each_byte

Calls the given block once for each byte in the stream.

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 268


def each_byte # :yields: byte
  while c = getc
    yield(c.ord)
  end
end

#each_line(eol = $/)

Alias for #each.

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 232


alias each_line each

#eof? ⇒ `Boolean` (readonly) Also known as: #eof

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

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 299


def eof?
  fill_rbuff if !@eof && @rbuffer.empty?
  @eof && @rbuffer.empty?
end

#fill_rbuff (private)

Fills the buffer from the underlying SSLSocket

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 55


def fill_rbuff
  begin
    @rbuffer << self.sysread(BLOCK_SIZE)
  rescue Errno::EAGAIN
    retry
  rescue EOFError
    @eof = true
  end
end

#flush

Flushes buffered data to the SSLSocket.

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 446


def flush
  osync = @sync
  @sync = true
  do_write ""
  return self
ensure
  @sync = osync
end

#getc

Reads one character from the stream. Returns nil if called at end of file.

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 261


def getc
  read(1)
end

#gets(eol = $/, limit = nil)

Reads the next “line” from the stream. Lines are separated by eol. If limit is provided the result will not be longer than the given number of bytes.

eol may be a String or Regexp.

Unlike IO#gets the line read will not be assigned to $_.

Unlike IO#gets the separator must be provided if a limit is provided.

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 203


def gets(eol=$/, limit=nil)
  idx = @rbuffer.index(eol)
  until @eof
    break if idx
    fill_rbuff
    idx = @rbuffer.index(eol)
  end
  if eol.is_a?(Regexp)
    size = idx ? idx+$&.size : nil
  else
    size = idx ? idx+eol.size : nil
  end
  if size && limit && limit >= 0
    size = [size, limit].min
  end
  consume_rbuff(size)
end

#initialize

Creates an instance of OpenSSL's buffering ::IO module.

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 40


def initialize(*)
  super
  @eof = false
  @rbuffer = ""
  @sync = @io.sync
end

#print(*args)

Writes args to the stream.

See IO#print for full details.

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 425


def print(*args)
  s = ""
  args.each{ |arg| s << arg.to_s }
  do_write(s)
  nil
end

#printf(s, *args)

Formats and writes to the stream converting parameters under control of the format string.

See Kernel.sprintf for format string details.

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 438


def printf(s, *args)
  do_write(s % args)
  nil
end

#puts(*args)

Writes args to the stream along with a record separator.

See IO#puts for full details.

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 405


def puts(*args)
  s = ""
  if args.empty?
    s << "\n"
  end
  args.each{|arg|
    s << arg.to_s
    if $/ && /\n\z/ !~ s
      s << "\n"
    end
  }
  do_write(s)
  nil
end

#read(size = nil, buf = nil)

Reads size bytes from the stream. If buf is provided it must reference a string which will receive the data.

See IO#read for full details.

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 87


def read(size=nil, buf=nil)
  if size == 0
    if buf
      buf.clear
      return buf
    else
      return ""
    end
  end
  until @eof
    break if size && size <= @rbuffer.size
    fill_rbuff
  end
  ret = consume_rbuff(size) || ""
  if buf
    buf.replace(ret)
    ret = buf
  end
  (size && ret.empty?) ? nil : ret
end

#read_nonblock(maxlen, buf = nil, exception: true)

Reads at most maxlen bytes in the non-blocking manner.

When no data can be read without blocking it raises SSL::SSLError extended by ::IO::WaitReadable or ::IO::WaitWritable.

::IO::WaitReadable means SSL needs to read internally so read_nonblock should be called again when the underlying ::IO is readable.

::IO::WaitWritable means SSL needs to write internally so read_nonblock should be called again after the underlying ::IO is writable.

read_nonblock needs two rescue clause as follows:

# emulates blocking read (readpartial).
begin
  result = ssl.read_nonblock(maxlen)
rescue IO::WaitReadable
  IO.select([io])
  retry
rescue IO::WaitWritable
  IO.select(nil, [io])
  retry
end

Note that one reason that read_nonblock writes to the underlying ::IO is when the peer requests a new TLS/SSL handshake. See openssl the FAQ for more details. www.openssl.org/support/faq.html

By specifying a keyword argument exception to false, you can indicate that read_nonblock should not raise an IO::Wait*able exception, but return the symbol :wait_writable or :wait_readable instead. At EOF, it will return nil instead of raising EOFError.

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 172


def read_nonblock(maxlen, buf=nil, exception: true)
  if maxlen == 0
    if buf
      buf.clear
      return buf
    else
      return ""
    end
  end
  if @rbuffer.empty?
    return sysread_nonblock(maxlen, buf, exception: exception)
  end
  ret = consume_rbuff(maxlen)
  if buf
    buf.replace(ret)
    ret = buf
  end
  ret
end

#readchar

Reads a one-character string from the stream. Raises an EOFError at end of file.

Raises:

(EOFError)

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 278


def readchar
  raise EOFError if eof?
  getc
end

#readline(eol = $/)

Reads a line from the stream which is separated by eol.

Raises EOFError if at end of file.

Raises:

(EOFError)

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 252


def readline(eol=$/)
  raise EOFError if eof?
  gets(eol)
end

#readlines(eol = $/)

Reads lines from the stream which are separated by eol.

#readpartial(maxlen, buf = nil)

Reads at most maxlen bytes from the stream. If buf is provided it must reference a string which will receive the data.

See IO#readpartial for full details.

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 114


def readpartial(maxlen, buf=nil)
  if maxlen == 0
    if buf
      buf.clear
      return buf
    else
      return ""
    end
  end
  if @rbuffer.empty?
    begin
      return sysread(maxlen, buf)
    rescue Errno::EAGAIN
      retry
    end
  end
  ret = consume_rbuff(maxlen)
  if buf
    buf.replace(ret)
    ret = buf
  end
  ret
end

#ungetc(c)

Pushes character c back onto the stream such that a subsequent buffered character read will return it.

Unlike IO#getc multiple bytes may be pushed back onto the stream.

Has no effect on unbuffered reads (such as #sysread).

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 291


def ungetc(c)
  @rbuffer[0,0] = c.chr
end

#write(*s)

Writes s to the stream. If the argument is not a String it will be converted using .to_s method. Returns the number of bytes written.

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 342


def write(*s)
  s.inject(0) do |written, str|
    do_write(str)
    written + str.bytesize
  end
end

#write_nonblock(s, exception: true)

Writes s in the non-blocking manner.

If there is buffered data, it is flushed first. This may block.

write_nonblock returns number of bytes written to the SSL connection.

When no data can be written without blocking it raises SSL::SSLError extended by ::IO::WaitReadable or ::IO::WaitWritable.

::IO::WaitReadable means SSL needs to read internally so write_nonblock should be called again after the underlying ::IO is readable.

::IO::WaitWritable means SSL needs to write internally so write_nonblock should be called again after underlying ::IO is writable.

So write_nonblock needs two rescue clause as follows.

# emulates blocking write.
begin
  result = ssl.write_nonblock(str)
rescue IO::WaitReadable
  IO.select([io])
  retry
rescue IO::WaitWritable
  IO.select(nil, [io])
  retry
end

Note that one reason that write_nonblock reads from the underlying ::IO is when the peer requests a new TLS/SSL handshake. See the openssl FAQ for more details. www.openssl.org/support/faq.html

By specifying a keyword argument exception to false, you can indicate that write_nonblock should not raise an IO::Wait*able exception, but return the symbol :wait_writable or :wait_readable instead.

[ GitHub ]

# File 'ext/openssl/lib/openssl/buffering.rb', line 386


def write_nonblock(s, exception: true)
  flush
  syswrite_nonblock(s, exception: exception)
end

Module: OpenSSL::Buffering

Overview

Constant Summary

Instance Attribute Summary

Instance Method Summary

Instance Attribute Details

#eof (readonly)

#sync (rw)

Instance Method Details

#<<(s)

#close

#consume_rbuff(size = nil) (private)

#do_write(s) (private)

#each(eol = $/) Also known as: #each_line

#each_byte

#each_line(eol = $/)

#eof? ⇒ Boolean (readonly) Also known as: #eof

#fill_rbuff (private)

#flush

#getc

#gets(eol = $/, limit = nil)

#initialize

#print(*args)

#printf(s, *args)

#puts(*args)

#read(size = nil, buf = nil)

#read_nonblock(maxlen, buf = nil, exception: true)

#readchar

#readline(eol = $/)

#readlines(eol = $/)

#readpartial(maxlen, buf = nil)

#ungetc(c)

#write(*s)

#write_nonblock(s, exception: true)

#eof? ⇒ `Boolean` (readonly) Also known as: #eof