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 88: def shellescape(str) 89: # An empty argument will be skipped, so return empty quotes. 90: return "''" if str.empty? 91: 92: str = str.dup 93: 94: # Process as a single byte sequence because not all shell 95: # implementations are multibyte aware. 96: str.gsub!(/([^A-Za-z0-9_\-.,:\/@\n])/n, "\\\\\\1") 97: 98: # A LF cannot be escaped with a backslash because a backslash + LF 99: # combo is regarded as line continuation and simply ignored. 100: str.gsub!(/\n/, "'\n'") 101: 102: return str 103: 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 125 125: def shelljoin(array) 126: array.map { |arg| shellescape(arg) }.join(' ') 127: 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 32: def shellsplit(line) 33: line = String.new(line) rescue 34: raise(ArgumentError, "Argument must be a string") 35: line.lstrip! 36: words = [] 37: until line.empty? 38: field = '' 39: loop do 40: if line.sub!(/\A"(([^"\\]|\\.)*)"/, '') then 41: snippet = $1.gsub(/\\(.)/, '\1') 42: elsif line =~ /\A"/ then 43: raise ArgumentError, "Unmatched double quote: #{line}" 44: elsif line.sub!(/\A'([^']*)'/, '') then 45: snippet = $1 46: elsif line =~ /\A'/ then 47: raise ArgumentError, "Unmatched single quote: #{line}" 48: elsif line.sub!(/\A\\(.)?/, '') then 49: snippet = $1 || '\\' 50: elsif line.sub!(/\A([^\s\\'"]+)/, '') then 51: snippet = $1 52: else 53: line.lstrip! 54: break 55: end 56: field.concat(snippet) 57: end 58: words.push(field) 59: end 60: words 61: end