Make cache directory creation more robust

If the top directories do not exist (in case we were run the first
to be run after fresh texlive install) try to make them first.

closes #17

1 files changed, 13 insertions, 11 deletions

diff --git a/otfl-luat-dum.lua b/otfl-luat-dum.lua
index e8e267a..9607697 100644
--- a/otfl-luat-dum.lua
+++ b/otfl-luat-dum.lua
@@ -92,24 +92,26 @@ end
 
 do
 
-    local cachepaths = kpse.expand_path('$TEXMFCACHE') or ""
+    local cachepaths
 
-    if cachepaths == "" then
-        cachepaths = kpse.expand_path('$TEXMFVAR')
+    if kpse.expand_var('$TEXMFCACHE') ~= '$TEXMFCACHE' then
+        cachepaths = kpse.expand_var('$TEXMFCACHE')
+    elseif kpse.expand_var('$TEXMFVAR') ~= '$TEXMFVAR' then
+        cachepaths = kpse.expand_var('$TEXMFVAR')
     end
 
-    if cachepaths == "" then
+    if not cachepaths then
         cachepaths = "."
     end
 
     cachepaths = string.split(cachepaths,os.type == "windows" and ";" or ":")
 
     for i=1,#cachepaths do
-        if file.iswritable(cachepaths[i]) then
-            writable = file.join(cachepaths[i],"luatex-cache")
-            lfs.mkdir(writable)
-            writable = file.join(writable,caches.namespace)
-            lfs.mkdir(writable)
+        local done
+        writable = file.join(cachepaths[i], "luatex-cache")
+        writable = file.join(writable,caches.namespace)
+        writable, done = dir.mkdirs(writable)
+        if done then
             break
         end
     end
@@ -121,10 +123,10 @@ do
     end
 
     if not writable then
-        texio.write_nl("quiting: fix your writable cache path")
+        texio.write_nl("quiting: fix your writable cache path\n")
         os.exit()
     elseif #readables == 0 then
-        texio.write_nl("quiting: fix your readable cache path")
+        texio.write_nl("quiting: fix your readable cache path\n")
         os.exit()
     elseif #readables == 1 and readables[1] == writable then
         texio.write(string.format("(using cache: %s)",writable))