#
# shellwords.rb: Manipulates strings a la UNIX Bourne shell
#
#
# This module manipulates strings according to the word parsing rules
# of the UNIX Bourne shell.
#
# The shellwords() function was originally a port of shellwords.pl,
# but modified to conform to POSIX / SUSv3 (IEEE Std 1003.1-2001).
#
# Authors:
# - Wakou Aoyama
# - Akinori MUSHA <knu@iDaemons.org>
#
# Contact:
# - Akinori MUSHA <knu@iDaemons.org> (current maintainer)
#
module Shellwords
#
# Splits a string into an array of tokens in the same way the UNIX
# Bourne shell does.
#
# argv = Shellwords.split('here are "two words"')
# argv #=> ["here", "are", "two words"]
#
# +String#shellsplit+ is a shorthand for this function.
#
# argv = 'here are "two words"'.shellsplit
# argv #=> ["here", "are", "two words"]
#
def shellsplit(line)
line = String.new(line) rescue
raise(ArgumentError, "Argument must be a string")
line.lstrip!
words = []
until line.empty?
field = ''
loop do
if line.sub!(/\A"(([^"\\]|\\.)*)"/, '') then
snippet = $1.gsub(/\\(.)/, '\1')
elsif line =~ /\A"/ then
raise ArgumentError, "Unmatched double quote: #{line}"
elsif line.sub!(/\A'([^']*)'/, '') then
snippet = $1
elsif line =~ /\A'/ then
raise ArgumentError, "Unmatched single quote: #{line}"
elsif line.sub!(/\A\\(.)?/, '') then
snippet = $1 || '\\'
elsif line.sub!(/\A([^\s\\'"]+)/, '') then
snippet = $1
else
line.lstrip!
break
end
field.concat(snippet)
end
words.push(field)
end
words
end
alias shellwords shellsplit
module_function :shellsplit, :shellwords
class << self
alias split shellsplit
end
#
# Escapes a string so that it can be safely used in a Bourne shell
# command line.
#
# Note that a resulted string should be used unquoted and is not
# intended for use in double quotes nor in single quotes.
#
# open("| grep #{Shellwords.escape(pattern)} file") { |pipe|
# # ...
# }
#
# +String#shellescape+ is a shorthand for this function.
#
# open("| grep #{pattern.shellescape} file") { |pipe|
# # ...
# }
#
def shellescape(str)
# An empty argument will be skipped, so return empty quotes.
return "''" if str.empty?
str = str.dup
# Process as a single byte sequence because not all shell
# implementations are multibyte aware.
str.gsub!(/([^A-Za-z0-9_\-.,:\/@\n])/n, "\\\\\\1")
# A LF cannot be escaped with a backslash because a backslash + LF
# combo is regarded as line continuation and simply ignored.
str.gsub!(/\n/, "'\n'")
return str
end
module_function :shellescape
class << self
alias escape shellescape
end
#
# Builds a command line string from an argument list +array+ joining
# all elements escaped for Bourne shell and separated by a space.
#
# open('|' + Shellwords.join(['grep', pattern, *files])) { |pipe|
# # ...
# }
#
# +Array#shelljoin+ is a shorthand for this function.
#
# open('|' + ['grep', pattern, *files].shelljoin) { |pipe|
# # ...
# }
#
def shelljoin(array)
array.map { |arg| shellescape(arg) }.join(' ')
end
module_function :shelljoin
class << self
alias join shelljoin
end
end
class String
#
# call-seq:
# str.shellsplit => array
#
# Splits +str+ into an array of tokens in the same way the UNIX
# Bourne shell does. See +Shellwords::shellsplit+ for details.
#
def shellsplit
Shellwords.split(self)
end
#
# call-seq:
# str.shellescape => string
#
# Escapes +str+ so that it can be safely used in a Bourne shell
# command line. See +Shellwords::shellescape+ for details.
#
def shellescape
Shellwords.escape(self)
end
end
class Array
#
# call-seq:
# array.shelljoin => string
#
# Builds a command line string from an argument list +array+ joining
# all elements escaped for Bourne shell and separated by a space.
# See +Shellwords::shelljoin+ for details.
#
def shelljoin
Shellwords.join(self)
end
end
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