avoid recursing into font dirs retrieved by kpse

minor speedup (some 16% with standard sized TL texmf), especially if the
directories are uncached.  as we take care of duplicate results from the
file scanner elsewhere this will not affect the list of fonts found.

1 files changed, 35 insertions, 5 deletions

diff --git a/luaotfload-database.lua b/luaotfload-database.lua
index 1b75458..b1d4877 100644
--- a/luaotfload-database.lua
+++ b/luaotfload-database.lua
@@ -1438,7 +1438,9 @@ process_dir_tree = function (acc, dirs)
                 then
                     dirs[#dirs+1] = fullpath
                 elseif lfsisfile (fullpath) then
-                    if lpegmatch (p_font_extensions, stringlower(ent)) then
+                    if lpegmatch (p_font_extensions,
+                                  stringlower (ent))
+                    then
                         newfiles[#newfiles+1] = fullpath
                     end
                 end
@@ -1450,10 +1452,38 @@ process_dir_tree = function (acc, dirs)
     return process_dir_tree (acc, dirs)
 end
 
---- string -> string list
-local find_font_files = function (root)
+local process_dir = function (dir)
+    local pwd = lfscurrentdir ()
+    if lfschdir (dir) then
+        lfschdir (pwd)
+
+        local files = { }
+        local blacklist = names.blacklist
+        for ent in lfsdir (dir) do
+            if ent ~= "." and ent ~= ".." and not blacklist[ent] then
+                local fullpath = dir .. "/" .. ent
+                if lfsisfile (fullpath) then
+                    if lpegmatch (p_font_extensions,
+                                  stringlower (ent))
+                    then
+                        files[#files+1] = fullpath
+                    end
+                end
+            end
+        end
+        return files
+    end
+    return { }
+end
+
+--- string -> bool -> string list
+local find_font_files = function (root, recurse)
     if lfsisdir (root) then
-        return process_dir_tree ({}, { root })
+        if recurse == true then
+            return process_dir_tree ({}, { root })
+        else --- kpathsea already delivered the necessary subdirs
+            return process_dir (root)
+        end
     end
 end
 
@@ -1478,7 +1508,7 @@ local scan_dir = function (dirname, fontnames, newfontnames,
         --- ignore
         return 0, 0
     end
-    local found = find_font_files (dirname)
+    local found = find_font_files (dirname, texmf ~= true)
     if not found then
         report ("both", 3, "db",
                 "No such directory: %q; skipping.", dirname)