CGI: pad error responses with 512 bytes of spaces so IE will display them

[ikiwiki.git] / IkiWiki / CGI.pm

diff --git a/IkiWiki/CGI.pm b/IkiWiki/CGI.pm
index f23d44fd6dd80a8707c78c9d74c39251a435bf9f..8734cdd494ece0d4f1a2229d0bed37542519495e 100644 (file)
--- a/IkiWiki/CGI.pm
+++ b/IkiWiki/CGI.pm
@@ -239,6 +239,9 @@ sub check_banned ($$) {
                        print $q->header(-status => "403 Forbidden");
                        $session->delete();
                        print gettext("You are banned.");
+                       # Internet Explorer won't show custom 404 responses
+                       # unless they're >= 512 bytes
+                       print " " x 512;
                        cgi_savesession($session);
                        exit;
                }
@@ -318,12 +321,15 @@ sub cgi_goto ($;$) {
        my $link = bestlink("", $page);
 
        if (! length $link) {
-               print "Content-type: text/html\n\n";
+               print $q->header(-status => "404 Not Found");
                print misctemplate(gettext("missing page"),
                        "<p>".
                        sprintf(gettext("The page %s does not exist."),
                                htmllink("", "", $page)).
-                       "</p>");
+                       "</p>".
+                       # Internet Explorer won't show custom 404 responses
+                       # unless they're >= 512 bytes
+                       (" " x 512));
        }
        else {
                redirect($q, urlto($link, undef, 1));
@@ -332,6 +338,46 @@ sub cgi_goto ($;$) {
        exit;
 }
 
+sub cgi_page_from_404 ($$$) {
+       my $path = shift;
+       my $baseurl = shift;
+       my $usedirs = shift;
+
+       # fail if missing from environment or whatever
+       return undef unless defined $path;
+       return undef unless defined $baseurl;
+
+       # with usedirs on, path is like /~fred/foo/bar/ or /~fred/foo/bar or
+       #    /~fred/foo/bar/index.html
+       # with usedirs off, path is like /~fred/foo/bar.html
+       # baseurl is like 'http://people.example.com/~fred'
+
+       # convert baseurl to ~fred
+       unless ($baseurl =~ s{^https?://[^/]+/?}{}) {
+               return undef;
+       }
+
+       # convert path to /~fred/foo/bar
+       if ($usedirs) {
+               $path =~ s/\/*(?:index\.$config{htmlext})?$//;
+       }
+       else {
+               $path =~ s/\.$config{htmlext}$//;
+       }
+
+       # remove /~fred/
+       unless ($path =~ s{^/*\Q$baseurl\E/*}{}) {
+               return undef;
+       }
+
+       # special case for the index
+       unless ($path) {
+               return 'index';
+       }
+
+       return $path;
+}
+
 sub cgi (;$$) {
        my $q=shift;
        my $session=shift;
@@ -363,7 +409,14 @@ sub cgi (;$$) {
        # commenter are for compatibility with any saved URLs
        if ($do eq 'goto' || $do eq 'recentchanges_link' ||
            $do eq 'commenter') {
-               cgi_goto($q);
+               my $page = undef;
+
+               if ($ENV{REDIRECT_STATUS} eq '404') {
+                       $page = cgi_page_from_404($ENV{REDIRECT_URL},
+                               $config{url}, $config{usedirs});
+               }
+
+               cgi_goto($q, $page);
        }
 
        # Need to lock the wiki before getting a session.