1 file changed, 3 insertions, 19 deletions
diff --git a/custom/extensions/about-render.lua b/custom/extensions/about-render.lua
index c19846e..62da9a8 100644
--- a/custom/extensions/about-render.lua
+++ b/custom/extensions/about-render.lua
@@ -1018,26 +1018,10 @@ end
 
 -- cgit takes filter output through a C string sink that stops at the first
 -- NUL byte, so each one becomes U+FFFD, as a browser would show it, and the
--- text past it survives. A plain find works on Lua 5.1, where a NUL cannot
--- sit in a pattern.
-local function replace_nul(text)
-	if not text:find("\0", 1, true) then
-		return text
-	end
-	local parts, start = {}, 1
-	while true do
-		local at = text:find("\0", start, true)
-		if not at then
-			parts[#parts + 1] = text:sub(start)
-			return table.concat(parts, "\239\191\189")
-		end
-		parts[#parts + 1] = text:sub(start, at - 1)
-		start = at + 1
-	end
-end
-
+-- text past it survives. The class names NUL as the one byte outside \1 to
+-- \255, since on Lua 5.1 a zero byte in a pattern ends it.
 function filter_close()
-	local text = replace_nul(table.concat(chunks))
+	local text = table.concat(chunks):gsub("[^\1-\255]", "\239\191\189")
 	chunks = {}
 	local ext = (filename:match("%.([^.]+)$") or ""):lower()
 	local render = #text <= max_bytes and handlers[ext] or render_plaintext