354886 - implement EXSLT - Regular Expressions module

Status: RESOLVED FIXED

(Core :: XSLT, enhancement)

Description

[Myk Melez [:myk] [@mykmelez]]

For some microsummary generators, it would be useful to be able to extract content from plaintext using regular expressions.

XPath 2 includes support for regexps, but implementing it would be a lot of work, so in the meantime the EXSLT - Regular Expressions module seems like the simplest way of adding regexp capabilities to XSLT.  We should implement it and include it with our XSLT processor.

Comment 1

[Peter Van der Beken [:peterv]]

Attachment: v1

Comment 2

[Peter Van der Beken [:peterv]]

Attachment: v1.1

Comment 3

[Jonas Sicking (:sicking) No longer reading bugmail consistently]

btw, i was holding off reviewing this until bug 193678 is in since there was some overlap.

Comment 4

[Peter Van der Beken [:peterv]]

Attachment: v2

Comment 5

[Peter Van der Beken [:peterv]]

Attachment: v2.1

This one compiles and works (tested using exslt.org testcases).

Comment 6

[Jonas Sicking (:sicking) No longer reading bugmail consistently]

Is there a risk that anything can be put in the expression or flags to make it possible to break out of regexp and execute script? I can't see anything though.

Comment 7

[Jonas Sicking (:sicking) No longer reading bugmail consistently]

Comment on attachment 246360 [details] [diff] [review]
v2.1

>Index: content/xslt/src/xslt/txStylesheetCompiler.cpp
>@@ -1062,7 +1078,49 @@ findFunction(nsIAtom* aName, PRInt32 aNa
>         }
>     }
> 
>-    return NS_ERROR_XPATH_UNKNOWN_FUNCTION;
>+    if (!sXPCOMFunctionMappings) {
>+        sXPCOMFunctionMappings = new nsTArray<txXPCOMFunctionMapping>;
>+    }

Check for OOM.

>+    txXPCOMFunctionMapping *map;

Please init this to nsnull. That way if we screw up somewhere it'll be a nullpointer deref rather than a security problem.

with that, r/sr=sicking

Comment 8

[Peter Van der Beken [:peterv]]

Attachment: Add JS component to package files v1

Comment 9

[Peter Van der Beken [:peterv]]

(In reply to comment #6)
> Is there a risk that anything can be put in the expression or flags to make it
> possible to break out of regexp and execute script? I can't see anything
> though.

Me neither.

Checked in with the additional patch to add the JS component to the package files.

Comment 10

[Jonas Sicking (:sicking) No longer reading bugmail consistently]

The regexp:match function is broken, see bug 363656