module OpenSSL::Buffering - RDoc Documentation (original) (raw)

OpenSSL IO buffering mix-in module.

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

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

Constants

BLOCK_SIZE

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

Attributes

sync[RW]

The “sync mode” of the SSLSocket.

See IO#sync for full details.

Public Class Methods

new(*) click to toggle source

Creates an instance of OpenSSL's buffering IO module.

Calls superclass method

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

Public Instance Methods

<<(s) click to toggle source

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

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

close() click to toggle source

Closes the SSLSocket and flushes any unwritten data.

def close flush rescue nil sysclose end

each(eol=$/) { |line| ... } click to toggle source

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

See also gets

def each(eol=$/) while line = self.gets(eol) yield line end end

each_byte() { |byte| ... } click to toggle source

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

def each_byte while c = getc yield(c.ord) end end

eof?() click to toggle source

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

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

Also aliased as: eof

flush() click to toggle source

Flushes buffered data to the SSLSocket.

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

getc() click to toggle source

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

gets(eol=$/, limit=nil) click to toggle source

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.

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

print(*args) click to toggle source

Writes args to the stream.

See IO#print for full details.

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

printf(s, *args) click to toggle source

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

See Kernel#sprintf for format string details.

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

puts(*args) click to toggle source

Writes args to the stream along with a record separator.

See IO#puts for full details.

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

read(size=nil, buf=nil) click to toggle source

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.

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) click to toggle source

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

When no data can be read without blocking it raises OpenSSL::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.

OpenSSL::Buffering#read_nonblock needs two rescue clause as follows:

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.

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() click to toggle source

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

def readchar raise EOFError if eof? getc end

readline(eol=$/) click to toggle source

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

Raises EOFError if at end of file.

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

readlines(eol=$/) click to toggle source

Reads lines from the stream which are separated by eol.

See also gets

def readlines(eol=$/) ary = [] while line = self.gets(eol) ary << line end ary end

readpartial(maxlen, buf=nil) click to toggle source

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.

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) click to toggle source

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).

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

write(*s) click to toggle source

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.

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

write_nonblock(s, exception: true) click to toggle source

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 OpenSSL::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 OpenSSL::Buffering#write_nonblock needs two rescue clause as follows.

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.

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

Private Instance Methods

consume_rbuff(size=nil) click to toggle source

Consumes size bytes from the buffer

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) click to toggle source

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

def do_write(s) @wbuffer = Buffer.new unless defined? @wbuffer @wbuffer << s @wbuffer.force_encoding(Encoding::BINARY) @sync ||= false if @sync or @wbuffer.size > BLOCK_SIZE until @wbuffer.empty? begin nwrote = syswrite(@wbuffer) rescue Errno::EAGAIN retry end @wbuffer[0, nwrote] = "" end end end

fill_rbuff() click to toggle source

Fills the buffer from the underlying SSLSocket

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