Bug#346154: igal: HTML in captions: don't replace '&' and strip HTML for title/alt/...

[gregor herrmann]

Package: igal
Version: 1.4-14
Severity: wishlist
Tags: patch

Today I detected that HTML is allowed in the .captions file. That's
nice (for the captions beneath the slides at large) but I stumbled
over two problems:
* s/&/&amp/ breaks any HTML entitites used in the captions.
* the captions are used for the page <TITLE>, for the alt/title
  attributes of <IMG>, <LINK>, the next/prev-links etc. - HTML makes
  no sense there or even contradicts HTML standards.
  
Find attached my patch that
* comments out the &-substitutions.
* introduces @captions_stripped containing captions without HTML tags
  by using a function called striphtml.

For the latter I used HTML::Scrubber; if you adopt the patch,
the package must therefore Depends: on libhtml-scrubber-perl.

Greetings,
gregor

-- System Information:
Debian Release: testing/unstable
  APT prefers testing
  APT policy: (990, 'testing'), (500, 'unstable'), (500, 'stable')
Architecture: i386 (i686)
Shell:  /bin/sh linked to /bin/bash
Kernel: Linux 2.4.31.20050730
Locale: LANG=C, [EMAIL PROTECTED] (charmap=ISO-8859-15)

Versions of packages igal depends on:
ii  imagemagick                6:6.2.4.5-0.2 Image manipulation programs
ii  libimage-size-perl         2.992-2       determine the size of images in se
ii  liburi-perl                1.35-1        Manipulates and accesses URI strin
ii  perl                       5.8.7-9       Larry Wall's Practical Extraction 

igal recommends no packages.

-- no debconf information

--- /usr/bin/igal.orig  2005-11-01 13:28:53.000000000 +0100
+++ /usr/bin/igal       2006-01-06 02:00:22.000000000 +0100
@@ -57,2 +57,7 @@
 
+# updated by gregor herrmann <[EMAIL PROTECTED]> 2006
+# * comment out substition of & by &amp; (breaks HTML entities in captions)
+# * stripped HTML from $title, $altname, etc. (taking the unmodified captions 
is
+#   not useful or not allowed if HTML is used in captions; using 
HTML::Scrubber)
+
 # this is az's local RCS version info: $Id: igal,v 1.24 2005/11/01 12:26:53 az 
Exp $ 
@@ -63,2 +68,3 @@
 use URI::Escape;
+use HTML::Scrubber;
 
@@ -223,3 +229,3 @@
 # Store image extensions, fix problematic filenames and complain
[EMAIL PROTECTED] = (); @captions = ();
[EMAIL PROTECTED] = (); @captions = (); @captions_stripped = ();
 my @safenames;
@@ -247,2 +253,3 @@
        push(@captions, $1);
+       push(@captions_stripped, striphtml($1));
        push(@imgnames, $1);
@@ -274,3 +281,3 @@
                @safenames = ();
-               @captions = (); @imgext = (); $njpg = 0;
+               @captions = (); @captions_stripped = (); @imgext = (); $njpg = 
0;
                print "Reading the $captionfile file ... ";
@@ -289,2 +296,3 @@
                                push(@captions,$arr[1]);
+                               push(@captions_stripped,striphtml($arr[1]));
                                $njpg++ if ($arr[0] =~ m/jpe?g/i);
@@ -478,3 +486,3 @@
                if ($opt_k) {    # use image caption for the HTML slide title
-                       $title = $captions[$i];
+                       $title = $captions_stripped[$i];
                } else {         # otherwise use the image name (strip suffix)
@@ -483,3 +491,4 @@
                }
-               $title=~s/&/&amp;/g; $title=~s/"/&\#34;/g;  # " make this 
attribute-safe
+               # $title=~s/&/&amp;/g;
+               $title=~s/"/&\#34;/g;  # " make this attribute-safe
                my @[EMAIL PROTECTED]; # don't touch the original template
@@ -527,4 +536,4 @@
                        {    
-                           $prev=$captions[$i-1];
-                           $next=$captions[($i==$nfiles-1?0:$i+1)];
+                           $prev=$captions_stripped[$i-1];
+                           $next=$captions_stripped[($i==$nfiles-1?0:$i+1)];
                        } 
@@ -536,4 +545,6 @@
 
-                           $prev=~s/&/&amp;/g; $prev=~s/"/&\#34;/g;  # " make 
this attribute-safe
-                           $next=~s/&/&amp;/g; $next=~s/"/&\#34;/g;  # " make 
this attribute-safe
+                           # $prev=~s/&/&amp;/g;
+                           $prev=~s/"/&\#34;/g;  # " make this attribute-safe
+                           # $next=~s/&/&amp;/g;
+                           $next=~s/"/&\#34;/g;  # " make this attribute-safe
                        }
@@ -647,3 +658,3 @@
                if ($opt_k) {    # use image caption for the alt attribute
-                   $altname = $captions[$i+$j];
+                   $altname = $captions_stripped[$i+$j];
                } else {         # otherwise use the image name (strip suffix)
@@ -653,3 +664,4 @@
 
-               $altname=~s/&/&amp;/g; $altname=~s/"/&\#34;/g;  # " make this 
attribute-safe
+               #$altname=~s/&/&amp;/g;
+               $altname=~s/"/&\#34;/g;  # " make this attribute-safe
                $thumb = $thumbprefix . $safenames[$i+$j];
@@ -746 +758,7 @@
 }
+
+sub striphtml {
+    local($html) = @_;
+               my $scrubber = HTML::Scrubber->new(default=>0);
+               return $scrubber->scrub($html); 
+}