Class: REXML::IOSource

Inherits:
Source show all
Defined in:
lib/rexml/source.rb

Overview

A Source that wraps an IO. See the Source class for method documentation

Instance Attribute Summary

Attributes inherited from Source

#buffer, #encoding, #line

Attributes included from Encoding

#encoding

Instance Method Summary collapse

Methods inherited from Source

#match_to, #match_to_consume

Methods included from Encoding

#check_encoding, #decode, #encode

Constructor Details

#initialize(arg, block_size = 500, encoding = nil) ⇒ IOSource

block_size has been deprecated



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# File 'lib/rexml/source.rb', line 136

def initialize(arg, block_size=500, encoding=nil)
  @er_source = @source = arg
  @to_utf = false

  # Determining the encoding is a deceptively difficult issue to resolve.
  # First, we check the first two bytes for UTF-16.  Then we
  # assume that the encoding is at least ASCII enough for the '>', and
  # we read until we get one of those.  This gives us the XML declaration,
  # if there is one.  If there isn't one, the file MUST be UTF-8, as per
  # the XML spec.  If there is one, we can determine the encoding from
  # it.
  @buffer = ""
  str = @source.read( 2 ) || ''
  if encoding
    self.encoding = encoding
  elsif str[0,2] == "\xfe\xff"
    @line_break = "\000>"
  elsif str[0,2] == "\xff\xfe"
    @line_break = ">\000"
  elsif str[0,2] == "\xef\xbb"
    str += @source.read(1)
    str = '' if (str[2,1] == "\xBF")
    @line_break = ">"
  else
    @line_break = ">"
  end
  super( @source.eof? ? str : str+@source.readline( @line_break ) )

  if !@to_utf and
      @buffer.respond_to?(:force_encoding) and
      @source.respond_to?(:external_encoding) and
      @source.external_encoding != ::Encoding::UTF_8
    @force_utf8 = true
  else
    @force_utf8 = false
  end
end

Instance Method Details

#consume(pattern) ⇒ Object 



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# File 'lib/rexml/source.rb', line 205

def consume( pattern )
  match( pattern, true )
end

#current_line ⇒ Object

Returns the current line in the source.

Returns:

  • the current line in the source



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# File 'lib/rexml/source.rb', line 234

def current_line
  begin
    pos = @er_source.pos        # The byte position in the source
    lineno = @er_source.lineno  # The XML < position in the source
    @er_source.rewind
    line = 0                    # The \r\n position in the source
    begin
      while @er_source.pos < pos
        @er_source.readline
        line += 1
      end
    rescue
    end
  rescue IOError
    pos = -1
    line = -1
  end
  [pos, lineno, line]
end

#empty? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rexml/source.rb', line 225

def empty?
  super and ( @source.nil? || @source.eof? )
end

#match(pattern, cons = false) ⇒ Object 



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# File 'lib/rexml/source.rb', line 209

def match( pattern, cons=false )
  rv = pattern.match(@buffer)
  @buffer = $' if cons and rv
  while !rv and @source
    begin
      @buffer << readline
      rv = pattern.match(@buffer)
      @buffer = $' if cons and rv
    rescue
      @source = nil
    end
  end
  rv.taint
  rv
end

#position ⇒ Object 



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# File 'lib/rexml/source.rb', line 229

def position
  @er_source.pos rescue 0
end

#read ⇒ Object 



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# File 'lib/rexml/source.rb', line 197

def read
  begin
    @buffer << readline
  rescue Exception, NameError
    @source = nil
  end
end

#scan(pattern, cons = false) ⇒ Object 



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# File 'lib/rexml/source.rb', line 174

def scan(pattern, cons=false)
  rv = super
  # You'll notice that this next section is very similar to the same
  # section in match(), but just a liiittle different.  This is
  # because it is a touch faster to do it this way with scan()
  # than the way match() does it; enough faster to warrent duplicating
  # some code
  if rv.size == 0
    until @buffer =~ pattern or @source.nil?
      begin
        @buffer << readline
      rescue Iconv::IllegalSequence
        raise
      rescue
        @source = nil
      end
    end
    rv = super
  end
  rv.taint
  rv
end