gitweb: do not run "git diff" that is Porcelain

Jakub says that legacy-style URI to view two blob differences are never
generated since 1.4.3.  This codepath runs "git diff" Porcelain from the
gitweb, which is a no-no.  It can trigger diff.external command that is
specified in the configuration file of the repository being viewed.

This patch applies to v1.5.4 and later.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/gitweb/gitweb.perl b/gitweb/gitweb.perl
index b582332f45ab278449182f2b2fe2d4be81ff38cb..86a6ced11a382ffe7b229b5f796c9cd8ffd4e845 100755 (executable)
--- a/gitweb/gitweb.perl
+++ b/gitweb/gitweb.perl
@@ -4809,43 +4809,9 @@ sub git_blobdiff {
                        or die_error(undef, "Open git-diff-tree failed");
        }
 
-       # old/legacy style URI
-       if (!%diffinfo && # if new style URI failed
-           defined $hash && defined $hash_parent) {
-               # fake git-diff-tree raw output
-               $diffinfo{'from_mode'} = $diffinfo{'to_mode'} = "blob";
-               $diffinfo{'from_id'} = $hash_parent;
-               $diffinfo{'to_id'}   = $hash;
-               if (defined $file_name) {
-                       if (defined $file_parent) {
-                               $diffinfo{'status'} = '2';
-                               $diffinfo{'from_file'} = $file_parent;
-                               $diffinfo{'to_file'}   = $file_name;
-                       } else { # assume not renamed
-                               $diffinfo{'status'} = '1';
-                               $diffinfo{'from_file'} = $file_name;
-                               $diffinfo{'to_file'}   = $file_name;
-                       }
-               } else { # no filename given
-                       $diffinfo{'status'} = '2';
-                       $diffinfo{'from_file'} = $hash_parent;
-                       $diffinfo{'to_file'}   = $hash;
-               }
-
-               # non-textual hash id's can be cached
-               if ($hash =~ m/^[0-9a-fA-F]{40}$/ &&
-                   $hash_parent =~ m/^[0-9a-fA-F]{40}$/) {
-                       $expires = '+1d';
-               }
-
-               # open patch output
-               open $fd, "-|", git_cmd(), "diff", @diff_opts,
-                       '-p', ($format eq 'html' ? "--full-index" : ()),
-                       $hash_parent, $hash, "--"
-                       or die_error(undef, "Open git-diff failed");
-       } else  {
+       # old/legacy style URI -- not generated anymore since 1.4.3.
+       if (!%diffinfo) {
                die_error('404 Not Found', "Missing one of the blob diff parameters")
-                       unless %diffinfo;
        }
 
        # header