[PATCH] gitweb: speed up project listing by limiting find depth

[Luke Lu <git@vicaya.com>]

Resubmit patch based on feedback from Shawn O. Pearce.

Signed-off-by: Luke Lu <git@vicaya.com>
---
 Makefile           |    2 ++
 gitweb/gitweb.perl |   11 +++++++++++
 2 files changed, 13 insertions(+), 0 deletions(-)

diff --git a/Makefile b/Makefile
index 8db4dbe..3e9938e 100644
--- a/Makefile
+++ b/Makefile
@@ -165,6 +165,7 @@ GITWEB_CONFIG = gitweb_config.perl
 GITWEB_HOME_LINK_STR = projects
 GITWEB_SITENAME =
 GITWEB_PROJECTROOT = /pub/git
+GITWEB_PROJECT_MAXDEPTH = 2007
 GITWEB_EXPORT_OK =
 GITWEB_STRICT_EXPORT =
 GITWEB_BASE_URL =
@@ -831,6 +832,7 @@ gitweb/gitweb.cgi: gitweb/gitweb.perl
 	    -e 's|++GITWEB_HOME_LINK_STR++|$(GITWEB_HOME_LINK_STR)|g' \
 	    -e 's|++GITWEB_SITENAME++|$(GITWEB_SITENAME)|g' \
 	    -e 's|++GITWEB_PROJECTROOT++|$(GITWEB_PROJECTROOT)|g' \
+	    -e 's|"++GITWEB_PROJECT_MAXDEPTH++"|$(GITWEB_PROJECT_MAXDEPTH)|g' \
 	    -e 's|++GITWEB_EXPORT_OK++|$(GITWEB_EXPORT_OK)|g' \
 	    -e 's|++GITWEB_STRICT_EXPORT++|$(GITWEB_STRICT_EXPORT)|g' \
 	    -e 's|++GITWEB_BASE_URL++|$(GITWEB_BASE_URL)|g' \
diff --git a/gitweb/gitweb.perl b/gitweb/gitweb.perl
index 3064298..5eb4414 100755
--- a/gitweb/gitweb.perl
+++ b/gitweb/gitweb.perl
@@ -35,6 +35,10 @@ our $GIT = "++GIT_BINDIR++/git";
 #our $projectroot = "/pub/scm";
 our $projectroot = "++GITWEB_PROJECTROOT++";
 
+# fs traversing limit for getting project list
+# the number is relative to the projectroot
+our $project_maxdepth = "++GITWEB_PROJECT_MAXDEPTH++";
+
 # target of the home link on top of all pages
 our $home_link = $my_uri || "/";
 
@@ -1509,16 +1513,23 @@ sub git_get_projects_list {
 		# remove the trailing "/"
 		$dir =~ s!/+$!!;
 		my $pfxlen = length("$dir");
+		my $pfxdepth = ($dir =~ tr!/!!);
 
 		File::Find::find({
 			follow_fast => 1, # follow symbolic links
 			follow_skip => 2, # ignore duplicates
+			no_chdir => 1, # don't chdir into every directory
 			dangling_symlinks => 0, # ignore dangling symlinks, silently
 			wanted => sub {
 				# skip project-list toplevel, if we get it.
 				return if (m!^[/.]$!);
 				# only directories can be git repositories
 				return unless (-d $_);
+				# don't traverse too deep (Find is super slow on os x)
+                                if (tr!/!! - $pfxdepth > $project_maxdepth) {
+                                  $File::Find::prune = 1;
+                                  return;
+                                }
 
 				my $subdir = substr($File::Find::name, $pfxlen + 1);
 				# we check related file in $projectroot
-- 
1.5.3.4