gitweb: retrieve snapshot format from PATH_INFO

We parse requests for $project/snapshot/$head.$sfx as equivalent to
$project/snapshot/$head?sf=$sfx, where $sfx is any of the known
(although not necessarily supported) snapshot formats (or its default
suffix).

The filename for the resulting package preserves the requested
extensions (so asking for a .tgz gives a .tgz, and asking for a .tar.gz
gives a .tar.gz), although for obvious reasons it doesn't preserve the
basename (git/snapshot/next.tgz returns a file names git-next.tgz).

This introduces a potential case for ambiguity if a project has a head
that ends with a snapshot-like suffix (.zip, .tgz, .tar.gz, etc) and the
sf CGI parameter is not present; however, gitweb only produces URLs with
the sf parameter currently, so this is only a potential issue for
hand-coded URLs for extremely unusual project.

Signed-off-by: Giuseppe Bilotta <giuseppe.bilotta@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/gitweb/gitweb.perl b/gitweb/gitweb.perl
index b4cd2620ff45257c7d1a44fc5614e627c6dfd84c..a7f35ccc87eee4d5457d8059cc051016c6d74a4b 100755 (executable)
--- a/gitweb/gitweb.perl
+++ b/gitweb/gitweb.perl
@@ -616,6 +616,45 @@ sub evaluate_path_info {
                        $input_params{'hash_parent'} ||= $parentrefname;
                }
        }
+
+       # for the snapshot action, we allow URLs in the form
+       # $project/snapshot/$hash.ext
+       # where .ext determines the snapshot and gets removed from the
+       # passed $refname to provide the $hash.
+       #
+       # To be able to tell that $refname includes the format extension, we
+       # require the following two conditions to be satisfied:
+       # - the hash input parameter MUST have been set from the $refname part
+       #   of the URL (i.e. they must be equal)
+       # - the snapshot format MUST NOT have been defined already (e.g. from
+       #   CGI parameter sf)
+       # It's also useless to try any matching unless $refname has a dot,
+       # so we check for that too
+       if (defined $input_params{'action'} &&
+               $input_params{'action'} eq 'snapshot' &&
+               defined $refname && index($refname, '.') != -1 &&
+               $refname eq $input_params{'hash'} &&
+               !defined $input_params{'snapshot_format'}) {
+               # We loop over the known snapshot formats, checking for
+               # extensions. Allowed extensions are both the defined suffix
+               # (which includes the initial dot already) and the snapshot
+               # format key itself, with a prepended dot
+               while (my ($fmt, %opt) = each %known_snapshot_formats) {
+                       my $hash = $refname;
+                       my $sfx;
+                       $hash =~ s/(\Q$opt{'suffix'}\E|\Q.$fmt\E)$//;
+                       next unless $sfx = $1;
+                       # a valid suffix was found, so set the snapshot format
+                       # and reset the hash parameter
+                       $input_params{'snapshot_format'} = $fmt;
+                       $input_params{'hash'} = $hash;
+                       # we also set the format suffix to the one requested
+                       # in the URL: this way a request for e.g. .tgz returns
+                       # a .tgz instead of a .tar.gz
+                       $known_snapshot_formats{$fmt}{'suffix'} = $sfx;
+                       last;
+               }
+       }
 }
 evaluate_path_info();