From 821e6aa045ecbb22dbc96d2dafe5f7ae1c839762 Mon Sep 17 00:00:00 2001
From: Philipp Gesang <phg42.2a@gmail.com>
Date: Sat, 12 Jul 2014 15:09:39 +0200
Subject: =?UTF-8?q?[conf]=20validate=20config=20variable=20=E2=80=9Cformat?=
 =?UTF-8?q?s=E2=80=9D?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Adds a validation function that checks whether the value is indeed a
list of comma-separated identifiers. Also, duplicate and invalid entries
are dropped from the result.
---
 src/luaotfload-configuration.lua | 46 +++++++++++++++++++++++++++++++++++++++-
 1 file changed, 45 insertions(+), 1 deletion(-)

(limited to 'src/luaotfload-configuration.lua')

diff --git a/src/luaotfload-configuration.lua b/src/luaotfload-configuration.lua
index ff90f68..937b050 100644
--- a/src/luaotfload-configuration.lua
+++ b/src/luaotfload-configuration.lua
@@ -31,6 +31,8 @@ local stringexplode           = string.explode
 local table                   = table
 local tableappend             = table.append
 local tablecopy               = table.copy
+local tableconcat             = table.concat
+local tabletohash             = table.tohash
 
 local math                    = math
 local mathfloor               = math.floor
@@ -44,6 +46,7 @@ local osgetenv                = os.getenv
 
 local lpeg                    = require "lpeg"
 local lpegmatch               = lpeg.match
+local lpegsplitter            = lpeg.splitat ","
 
 local kpse                    = kpse
 local kpseexpand_path         = kpse.expand_path
@@ -91,6 +94,11 @@ local config_paths = {
   { kpse_t, "luaotfload.conf" },
 }
 
+local valid_formats = tabletohash {
+  "otf",   "ttc", "ttf", "dfont", "afm", "pfb", "pfa",
+}
+
+
 -------------------------------------------------------------------------------
 ---                                DEFAULTS
 -------------------------------------------------------------------------------
@@ -253,7 +261,43 @@ end
 
 local option_spec = {
   db = {
-    formats      = { in_t = string_t,  },
+    formats      = {
+      in_t  = string_t,
+      out_t = string_t,
+      transform = function (f)
+        local fields = { lpegmatch (lpegsplitter, f) }
+
+        --- check validity
+        if not fields then
+          logreport ("both", 0, "conf",
+                     "Expected list of identifiers, got %q.", f)
+          return nil
+        end
+
+        --- strip dupes
+        local known  = { }
+        local result = { }
+        for i = 1, #fields do
+          local field = fields[i]
+          if known[field] ~= true then
+            --- yet unknown, tag as seen
+            known[field] = true
+            --- include in output if valid
+            if valid_formats[field] == true then
+              result[#result + 1] = field
+            else
+              logreport ("both", 4, "conf",
+                          "Invalid font format identifier %q, ignoring.", field)
+            end
+          end
+        end
+        if #result == 0 then
+          --- force defaults
+          return nil
+        end
+        return tableconcat (result, ",")
+      end
+    },
     reload       = { in_t = boolean_t, },
     scan_local   = { in_t = boolean_t, },
     skip_read    = { in_t = boolean_t, },
-- 
cgit v1.2.3