Bug #5322: URI.decode_www_form_component very slow with certain inputs

• Status: Closed
• Assignee: -
• Target version: 1.9.2
• ruby -v: ruby 1.9.2p290 (2011-07-09 revision 32553) [x86_64-darwin11.0.1]

[rasmusrn (Rasmus Rønn Nielsen)]

When calling the following I get what I'd expect. An error.

URI.decode_www_form_component("aaaaaaaaaaaaaaaaaaaa%")

Here's the IRB output:

ruby-1.9.2-p290 :003 > URI.decode_www_form_component("aaaaaaaaaaaaaaaaaaaa%")
ArgumentError: invalid %-encoding (aaaaaaaaaaaaaaaaaaaa%)
from /Users/rasmus/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/uri/common.rb:778:in decode_www_form_component' from (irb):3 rom /Users/rasmus/.rvm/rubies/ruby-1.9.2-p290/bin/irb:16:in '

But as I add more characters to the string, the execution becomes much much slower. I would expect it to be a lot faster than it is.

URI.decode_www_form_component("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa%")

Add more characters and the call would take hours, if not days.

Related blog post: http://rrn.dk/running-ruby-process-callstack

I've reproduced this bug on these rubies:
ruby 1.9.2p290 (2011-07-09 revision 32553) [x86_64-darwin11.0.1]
ruby 1.9.2p290 (2011-07-09 revision 32553) [x86_64-linux]

[regularfry (Alex Young)]

Looks like a duplicate of #5149 to me...

[naruse (Yui NARUSE)]

• Status changed from Open to Closed