From 1f14a9e80dd4cef40a1e1976196b38450a1e096f Mon Sep 17 00:00:00 2001
From: frankyifei <fredyifei@gmail.com>
Date: Thu, 22 Oct 2015 19:32:21 +1030
Subject: [PATCH 1/3] try to exclude those broken system fonts

these fonts can not be used by freetype and will cause hang up
---
 frontend/ui/font.lua | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/frontend/ui/font.lua b/frontend/ui/font.lua
index b1b9d96f4..d74f24b84 100644
--- a/frontend/ui/font.lua
+++ b/frontend/ui/font.lua
@@ -82,6 +82,26 @@ function Font:getFace(font, size)
     return face_obj
 end
 
+function checkfont(f)
+    local exclusive_system_font = {
+    --these kindle system fonts can not be used by freetype and will give error
+        "HYGothicBold.ttf",
+        "HYGothicMedium.ttf",
+        "HYMyeongJoBold.ttf",
+        "HYMyeongJoMedium.ttf",
+        "MYingHeiTBold.ttf",
+        "MYingHeiTMedium.ttf",
+        "SongTBold.ttf",
+        "SongTMedium.ttf"
+        }
+    for _,value in ipairs(exclusive_system_font) do
+        if value == f then
+            return true
+        end
+    end
+    return false
+end
+
 function Font:_readList(target, dir)
     -- lfs.dir non-exsitent directory will give error, weird!
     local ok, iter, dir_obj = pcall(lfs.dir, dir)
@@ -93,7 +113,9 @@ function Font:_readList(target, dir)
             local file_type = string.lower(string.match(f, ".+%.([^.]+)") or "")
             if file_type == "ttf" or file_type == "ttc"
                 or file_type == "cff" or file_type == "otf" then
-                table.insert(target, dir.."/"..f)
+                if checkfont(f) ~=true then
+                    table.insert(target, dir.."/"..f)
+                end
             end
         end
     end

From 86d6d46770550185d10251e99fb2c4f69bdbfb70 Mon Sep 17 00:00:00 2001
From: frankyifei <fredyifei@gmail.com>
Date: Thu, 22 Oct 2015 23:49:34 +1030
Subject: [PATCH 2/3] add isKindle check

---
 frontend/ui/font.lua | 32 +++++++++++++++++---------------
 1 file changed, 17 insertions(+), 15 deletions(-)

diff --git a/frontend/ui/font.lua b/frontend/ui/font.lua
index d74f24b84..4553e6d3b 100644
--- a/frontend/ui/font.lua
+++ b/frontend/ui/font.lua
@@ -83,23 +83,25 @@ function Font:getFace(font, size)
 end
 
 function checkfont(f)
-    local exclusive_system_font = {
-    --these kindle system fonts can not be used by freetype and will give error
-        "HYGothicBold.ttf",
-        "HYGothicMedium.ttf",
-        "HYMyeongJoBold.ttf",
-        "HYMyeongJoMedium.ttf",
-        "MYingHeiTBold.ttf",
-        "MYingHeiTMedium.ttf",
-        "SongTBold.ttf",
-        "SongTMedium.ttf"
-        }
-    for _,value in ipairs(exclusive_system_font) do
-        if value == f then
-            return true
+    if Device:isKindle() then
+        local exclusive_system_font = {
+        --these kindle system fonts can not be used by freetype and will give error
+            "HYGothicBold.ttf",
+            "HYGothicMedium.ttf",
+            "HYMyeongJoBold.ttf",
+            "HYMyeongJoMedium.ttf",
+            "MYingHeiTBold.ttf",
+            "MYingHeiTMedium.ttf",
+            "SongTBold.ttf",
+            "SongTMedium.ttf"
+            }
+        for _,value in ipairs(exclusive_system_font) do
+            if value == f then
+                return true
+            end
         end
+    else return false
     end
-    return false
 end
 
 function Font:_readList(target, dir)

From 55ba1450d4351124b720780c3a527e3caa2a6c65 Mon Sep 17 00:00:00 2001
From: chrox <chrox.huang@gmail.com>
Date: Thu, 22 Oct 2015 23:15:41 +0800
Subject: [PATCH 3/3] code refactoring: use hash table index instead of loop

---
 frontend/ui/font.lua | 37 +++++++++++++++++--------------------
 1 file changed, 17 insertions(+), 20 deletions(-)

diff --git a/frontend/ui/font.lua b/frontend/ui/font.lua
index 4553e6d3b..d42222108 100644
--- a/frontend/ui/font.lua
+++ b/frontend/ui/font.lua
@@ -47,7 +47,6 @@ local Font = {
     faces = {},
 }
 
-
 function Font:getFace(font, size)
     -- default to content font
     if not font then font = self.cfont end
@@ -82,25 +81,23 @@ function Font:getFace(font, size)
     return face_obj
 end
 
-function checkfont(f)
+--[[
+    These fonts from Kindle system cannot be loaded by Freetype.
+--]]
+local kindle_fonts_blacklist = {
+    ["HYGothicBold.ttf"] = true,
+    ["HYGothicMedium.ttf"] = true,
+    ["HYMyeongJoBold.ttf"] = true,
+    ["HYMyeongJoMedium.ttf"] = true,
+    ["MYingHeiTBold.ttf"] = true,
+    ["MYingHeiTMedium.ttf"] = true,
+    ["SongTBold.ttf"] = true,
+    ["SongTMedium.ttf"] = true,
+}
+
+local function isInFontsBlacklist(f)
     if Device:isKindle() then
-        local exclusive_system_font = {
-        --these kindle system fonts can not be used by freetype and will give error
-            "HYGothicBold.ttf",
-            "HYGothicMedium.ttf",
-            "HYMyeongJoBold.ttf",
-            "HYMyeongJoMedium.ttf",
-            "MYingHeiTBold.ttf",
-            "MYingHeiTMedium.ttf",
-            "SongTBold.ttf",
-            "SongTMedium.ttf"
-            }
-        for _,value in ipairs(exclusive_system_font) do
-            if value == f then
-                return true
-            end
-        end
-    else return false
+        return kindle_fonts_blacklist[f]
     end
 end
 
@@ -115,7 +112,7 @@ function Font:_readList(target, dir)
             local file_type = string.lower(string.match(f, ".+%.([^.]+)") or "")
             if file_type == "ttf" or file_type == "ttc"
                 or file_type == "cff" or file_type == "otf" then
-                if checkfont(f) ~=true then
+                if not isInFontsBlacklist(f) then
                     table.insert(target, dir.."/"..f)
                 end
             end