gitweb: optionally read config from GITWEB_CONFIG

Configuration will first be taken from variables inside the gitweb.cgi
script, which in turn come from the Makefile. Afterwards, the contents of
GITWEB_CONFIG are read, overriding the builtin defaults.

This should eliminate the need for editing the gitweb script at all. Users
should edit the Makefile and/or add a config file.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <junkio@cox.net>

Makefile

@@ -117,6 +117,7 @@ GIT_PYTHON_DIR = $(prefix)/share/git-core/python
 # DESTDIR=
 
 # default configuration for gitweb
+GITWEB_CONFIG = gitweb_config.perl
 GITWEB_SITENAME =
 GITWEB_PROJECTROOT = /pub/git
 GITWEB_LIST =
@@ -585,6 +586,7 @@ gitweb/gitweb.cgi: gitweb/gitweb.perl
 	sed -e '1s|#!.*perl|#!$(PERL_PATH_SQ)|' \
 	    -e 's|@@GIT_VERSION@@|$(GIT_VERSION)|g' \
 	    -e 's|@@GIT_BINDIR@@|$(bindir)|g' \
+	    -e 's|@@GITWEB_CONFIG@@|$(GITWEB_CONFIG)|g' \
 	    -e 's|@@GITWEB_SITENAME@@|$(GITWEB_SITENAME)|g' \
 	    -e 's|@@GITWEB_PROJECTROOT@@|$(GITWEB_PROJECTROOT)|g' \
 	    -e 's|@@GITWEB_LIST@@|$(GITWEB_LIST)|g' \

gitweb/gitweb.perl

@@ -31,14 +31,8 @@ our $GIT = "@@GIT_BINDIR@@/git";
 #our $projectroot = "/pub/scm";
 our $projectroot = "@@GITWEB_PROJECTROOT@@";
 
-# version of the core git binary
-our $git_version = qx($GIT --version) =~ m/git version (.*)$/ ? $1 : "unknown";
-
 # location for temporary files needed for diffs
 our $git_temp = "/tmp/gitweb";
-if (! -d $git_temp) {
-	mkdir($git_temp, 0700) || die_error("Couldn't mkdir $git_temp");
-}
 
 # target of the home link on top of all pages
 our $home_link = $my_uri;
@@ -56,7 +50,7 @@ our $stylesheet = "@@GITWEB_CSS@@";
 our $logo = "@@GITWEB_LOGO@@";
 
 # source of projects list
-our $projects_list = "@@GITWEB_LIST@@" || "$projectroot";
+our $projects_list = "@@GITWEB_LIST@@";
 
 # default blob_plain mimetype and default charset for text/plain blob
 our $default_blob_plain_mimetype = 'text/plain';
@@ -66,6 +60,17 @@ our $default_text_plain_charset  = undef;
 # (relative to the current git repository)
 our $mimetypes_file = undef;
 
+our $GITWEB_CONFIG = "@@GITWEB_CONFIG@@";
+require $GITWEB_CONFIG if -e $GITWEB_CONFIG;
+
+# version of the core git binary
+our $git_version = qx($GIT --version) =~ m/git version (.*)$/ ? $1 : "unknown";
+
+$projects_list ||= $projectroot;
+if (! -d $git_temp) {
+	mkdir($git_temp, 0700) || die_error("Couldn't mkdir $git_temp");
+}
+
 # input validation and dispatch
 our $action = $cgi->param('a');
 if (defined $action) {