Merge pull request #1030 from chrox/fix_1028

fix #1028

frontend/cache.lua

@@ -69,8 +69,8 @@ end
 function Cache:insert(key, object)
     -- guarantee that we have enough memory in cache
     if(object.size > self.max_memsize) then
-        -- we're not allowed to claim this much at all
-        error("too much memory claimed")
+        DEBUG("too much memory claimed for", key)
+        return
     end
     -- delete objects that least recently used
     -- (they are at the end of the cache_order array)

frontend/document/credocument.lua

@@ -148,9 +148,11 @@ function CreDocument:getCoverPageImage()
     local data, size = self._document:getCoverPageImageData()
     if data and size then
         local Mupdf = require("ffi/mupdf")
-        local image = Mupdf.renderImage(data, size)
-        ffi.C.free(data)
-        return image
+        local ok, image = pcall(Mupdf.renderImage, data, size)
+        if ok then
+            ffi.C.free(data)
+            return image
+        end
     end
 end