hotfix snax supported

lualib/snax_hotfix.lua

@@ -0,0 +1,107 @@
+local si = require "snax_interface"
+local io = io
+
+local hotfix = {}
+
+local function loader(filename, ...)
+	local f = io.open(filename, "rb")
+	if not f then
+		return false, string.format("Can't open %s", filename)
+	end
+	local source = f:read "*a"
+	f:close()
+
+	return load(source, "@"..filename, ...)
+end
+
+local function check_funcs(f1,f2)
+	for k,a in pairs(f1) do
+		local b = f2[k]
+		assert(a[1] == b[1] and a[2] == b[2] and a[3] == b[3] ,
+			string.format("%s.%s %s.%s , function mismatch", a[2], a[3] , b[2], b[3]))
+	end
+end
+
+local function get_upvalues(f, global)
+	local uv = {}
+	local i = 1
+	while true do
+		local name = debug.getupvalue(f, i)
+		if name then
+			local uid = debug.upvalueid(f, i)
+			uv[name] = i
+			if global[name] and global[name][1] ~= uid then
+				error(string.format("ambiguity upvalue %s", name))
+			end
+			global[name] = { uid , f , i }
+		else
+			break
+		end
+		i = i + 1
+	end
+	return uv
+end
+
+local function join_upvalues(f, new_f, uv)
+	local i = 1
+	while true do
+		local name = debug.getupvalue(new_f, i)
+		if name then
+			if uv[name] then
+				debug.upvaluejoin(new_f, i, f, uv[name])
+			end
+		else
+			break
+		end
+		i = i + 1
+	end
+end
+
+local function join_global_upvalues(f, global)
+	local i = 1
+	while true do
+		local name = debug.getupvalue(f, i)
+		if name then
+			local uv = global[name]
+			if uv then
+				debug.upvaluejoin(f, i, uv[2], uv[3])
+			end
+		else
+			break
+		end
+		i = i + 1
+	end
+end
+
+local function update_upvalues(funcs, newfuncs)
+	local global = {}
+	for id,v in pairs(funcs) do
+		local f = v[4]
+		local new_f = newfuncs[id][4]
+		if f and new_f then
+			local uv = get_upvalues(f, global)
+			v[4] = new_f
+			join_upvalues(f, new_f, uv)
+			newfuncs[id] = nil
+		end
+	end
+	for id,v in pairs(newfuncs) do
+		if v[2] == "system" then
+			funcs[id] = v
+			local f = v[4]
+			join_global_upvalues(f, global)
+		else
+			error(string.format("Detect unkown function %s.%s", v[2], v[3]))
+		end
+	end
+end
+
+local function inject(funcs, new)
+	check_funcs(funcs, new)
+	update_upvalues(funcs, new)
+end
+
+return function (funcs, modname)
+	local new_funcs = si(modname, _ENV, loader)
+	return pcall(inject, funcs, new_funcs)
+end