move lualib/snax_* to lualib/snax/

lualib/snax/hotfix.lua

@@ -0,0 +1,94 @@
+local si = require "snax.interface"
+local io = io
+
+local hotfix = {}
+
+local function collect_uv(f , uv)
+	local i = 1
+	while true do
+		local name, value = debug.getupvalue(f, i)
+		if name == nil then
+			break
+		end
+		local id = debug.upvalueid(f, i)
+
+		if uv[name] then
+			assert(uv[name].id == id, string.format("ambiguity local value %s", name))
+		else
+			uv[name] = { func = f, index = i, id = id }
+
+			if type(value) == "function" then
+				collect_uv(value, uv)
+			end
+		end
+
+		i = i + 1
+	end
+end
+
+local function collect_all_uv(funcs)
+	local global = {}
+	for _, v in pairs(funcs) do
+		if v[4] then
+			collect_uv(v[4], global)
+		end
+	end
+
+	return global
+end
+
+local function loader(source)
+	return function (filename, ...)
+		return load(source, "=patch", ...)
+	end
+end
+
+local function find_func(funcs, group , name)
+	for _, desc in pairs(funcs) do
+		local _, g, n = table.unpack(desc)
+		if group == g and name == n then
+			return desc
+		end
+	end
+end
+
+local dummy_env = {}
+
+local function patch_func(funcs, global, group, name, f)
+	local desc = assert(find_func(funcs, group, name) , string.format("Patch mismatch %s.%s", group, name))
+	local i = 1
+	while true do
+		local name, value = debug.getupvalue(f, i)
+		if name == nil then
+			break
+		elseif value == nil or value == dummy_env then
+			local old_uv = global[name]
+			if old_uv then
+				debug.upvaluejoin(f, i, old_uv.func, old_uv.index)
+			end
+		end
+		i = i + 1
+	end
+	desc[4] = f
+end
+
+local function inject(funcs, source, ...)
+	local patch = si("patch", dummy_env, loader(source))
+	local global = collect_all_uv(funcs)
+
+	for _, v in pairs(patch) do
+		local _, group, name, f = table.unpack(v)
+		if f then
+			patch_func(funcs, global, group, name, f)
+		end
+	end
+
+	local hf = find_func(patch, "system", "hotfix")
+	if hf and hf[4] then
+		return hf[4](...)
+	end
+end
+
+return function (funcs, source, ...)
+	return pcall(inject, funcs, source, ...)
+end