metasploit-framework/lib/rex/ui/text/input/readline.rb

157 lines
3.5 KiB
Ruby

# -*- coding: binary -*-
require 'rex/ui'
module Rex
module Ui
module Text
begin
###
#
# This class implements standard input using readline against
# standard input. It supports tab completion.
#
###
class Input::Readline < Rex::Ui::Text::Input
#
# Initializes the readline-aware Input instance for text.
#
def initialize(tab_complete_proc = nil)
if(not Object.const_defined?('Readline'))
require 'readline'
end
self.extend(::Readline)
if (tab_complete_proc)
::Readline.basic_word_break_characters = "\x00"
::Readline.completion_proc = tab_complete_proc
@rl_saved_proc = tab_complete_proc
end
end
#
# Reattach the original completion proc
#
def reset_tab_completion(tab_complete_proc = nil)
::Readline.basic_word_break_characters = "\x00"
::Readline.completion_proc = tab_complete_proc || @rl_saved_proc
end
#
# Whether or not the input medium supports readline.
#
def supports_readline
true
end
#
# Calls sysread on the standard input handle.
#
def sysread(len = 1)
begin
self.fd.sysread(len)
rescue ::Errno::EINTR
retry
end
end
#
# Read a line from stdin
#
def gets()
begin
self.fd.gets()
rescue ::Errno::EINTR
retry
end
end
#
# Stick readline into a low-priority thread so that the scheduler doesn't slow
# down other background threads. This is important when there are many active
# background jobs, such as when the user is running Karmetasploit
#
def pgets()
line = nil
orig = Thread.current.priority
begin
Thread.current.priority = -20
output.prompting
line = readline_with_output(prompt, true)
::Readline::HISTORY.pop if (line and line.empty?)
ensure
Thread.current.priority = orig || 0
end
line
end
#
# Returns the output pipe handle
#
def fd
$stdin
end
#
# Indicates that this input medium as a shell builtin, no need
# to extend.
#
def intrinsic_shell?
true
end
#
# The prompt that is to be displayed.
#
attr_accessor :prompt
#
# The output handle to use when displaying the prompt.
#
attr_accessor :output
private
def readline_with_output(prompt, add_history=false)
# rb-readlines's Readline.readline hardcodes the input and output to $stdin and $stdout, which means setting
# `Readline.input` or `Readline.ouput` has no effect when running `Readline.readline` with rb-readline, so need
# to reimplement []`Readline.readline`](https://github.com/luislavena/rb-readline/blob/ce4908dae45dbcae90a6e42e3710b8c3a1f2cd64/lib/readline.rb#L36-L58)
# for rb-readline to support setting input and output. Output needs to be set so that colorization works for the
# prompt on Windows.
if defined? RbReadline
RbReadline.rl_instream = fd
RbReadline.rl_outstream = output
begin
line = RbReadline.readline(prompt)
rescue ::Exception => exception
RbReadline.rl_cleanup_after_signal()
RbReadline.rl_deprep_terminal()
raise exception
end
if add_history && line
RbReadline.add_history(line)
end
line.try(:dup)
else
::Readline.readline(prompt, true)
end
end
end
rescue LoadError
end
end
end
end