gitweb: allow extra breadcrumbs to prefix the trail

There are often parent pages logically above the gitweb projects
list, e.g. home pages of the organization and department that host
the gitweb server. This change allows you to include links to those
pages in gitweb's breadcrumb trail.

Signed-off-by: Tony Finch <[email protected]>
Reviewed-by: Jonathan Nieder <[email protected]>
Acked-by: Jakub Narebski <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: fanf2

Documentation/gitweb.conf.txt

@@ -336,8 +336,26 @@ $home_link_str::
 	used as the first component of gitweb's "breadcrumb trail":
 	`<home link> / <project> / <action>`.  Can be set at build time using
 	the `GITWEB_HOME_LINK_STR` variable.  By default it is set to "projects",
-	as this link leads to the list of projects.  Other popular choice it to
-	set it to the name of site.
+	as this link leads to the list of projects.  Another popular choice is to
+	set it to the name of site.  Note that it is treated as raw HTML so it
+	should not be set from untrusted sources.
+
+@extra_breadcrumbs::
+	Additional links to be added to the start of the breadcrumb trail before
+	the home link, to pages that are logically "above" the gitweb projects
+	list, such as the organization and department which host the gitweb
+	server. Each element of the list is a reference to an array, in which
+	element 0 is the link text (equivalent to `$home_link_str`) and element
+	1 is the target URL (equivalent to `$home_link`).
++
+For example, the following setting produces a breadcrumb trail like
+"home / dev / projects / ..." where "projects" is the home link.
+----------------------------------------------------------------------------
+    our @extra_breadcrumbs = (
+      [ 'home' => 'https://www.example.org/' ],
+      [ 'dev'  => 'https://dev.example.org/' ],
+    );
+----------------------------------------------------------------------------
 
 $logo_url::
 $logo_label::

gitweb/gitweb.perl

@@ -85,6 +85,9 @@ sub evaluate_uri {
 # string of the home link on top of all pages
 our $home_link_str = "++GITWEB_HOME_LINK_STR++";
 
+# extra breadcrumbs preceding the home link
+our @extra_breadcrumbs = ();
+
 # name of your site or organization to appear in page titles
 # replace this with something more descriptive for clearer bookmarks
 our $site_name = "++GITWEB_SITENAME++"
@@ -3982,7 +3985,9 @@ sub print_nav_breadcrumbs_path {
 sub print_nav_breadcrumbs {
 	my %opts = @_;
 
-	print $cgi->a({-href => esc_url($home_link)}, $home_link_str) . " / ";
+	for my $crumb (@extra_breadcrumbs, [ $home_link_str => $home_link ]) {
+		print $cgi->a({-href => esc_url($crumb->[1])}, $crumb->[0]) . " / ";
+	}
 	if (defined $project) {
 		my @dirname = split '/', $project;
 		my $projectbasename = pop @dirname;