Module | Shellwords |
In: |
lib/shellwords.rb
|
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)
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| # ... }
# File lib/shellwords.rb, line 88 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
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| # ... }
# File lib/shellwords.rb, line 125 def shelljoin(array) array.map { |arg| shellescape(arg) }.join(' ') end
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"]
# File lib/shellwords.rb, line 32 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