From 3164569a22b62c28bd710f6471740b04dcbc8090 Mon Sep 17 00:00:00 2001 From: ShadowNinja Date: Thu, 8 May 2014 23:56:36 -0400 Subject: [PATCH] Rework dumping functions Changes: * Add comments to explain the dumping code * Add support for dumping values of any type (as '<' '>') * Add support for tables as keys in dump2() * Make dump2() return it's result (like dump()) rather than printing it * Simplify and optimize function serialization via serialize() --- builtin/common/misc_helpers.lua | 118 +++++++++++++++++++------------- builtin/common/serialize.lua | 2 +- 2 files changed, 71 insertions(+), 49 deletions(-) diff --git a/builtin/common/misc_helpers.lua b/builtin/common/misc_helpers.lua index 38a7b18..e53ca37 100644 --- a/builtin/common/misc_helpers.lua +++ b/builtin/common/misc_helpers.lua @@ -1,79 +1,101 @@ -- Minetest: builtin/misc_helpers.lua -------------------------------------------------------------------------------- -function basic_dump2(o) - if type(o) == "number" then +function basic_dump(o) + local tp = type(o) + if tp == "number" then return tostring(o) - elseif type(o) == "string" then + elseif tp == "string" then return string.format("%q", o) - elseif type(o) == "boolean" then + elseif tp == "boolean" then return tostring(o) - elseif type(o) == "function" then - return "" - elseif type(o) == "userdata" then - return "" - elseif type(o) == "nil" then + elseif tp == "nil" then return "nil" + -- Uncomment for full function dumping support. + -- Not currently enabled because bytecode isn't very human-readable and + -- dump's output is intended for humans. + --elseif tp == "function" then + -- return string.format("loadstring(%q)", string.dump(o)) else - error("cannot dump a " .. type(o)) - return nil + return string.format("<%s>", tp) end end -------------------------------------------------------------------------------- +-- Dumps values in a line-per-value format. +-- For example, {test = {"Testing..."}} becomes: +-- _["test"] = {} +-- _["test"][1] = "Testing..." +-- This handles tables as keys and circular references properly. +-- It also handles multiple references well, writing the table only once. +-- The dumped argument is internal-only. + function dump2(o, name, dumped) name = name or "_" + -- "dumped" is used to keep track of serialized tables to handle + -- multiple references and circular tables properly. + -- It only contains tables as keys. The value is the name that + -- the table has in the dump, eg: + -- {x = {"y"}} -> dumped[{"y"}] = '_["x"]' dumped = dumped or {} - io.write(name, " = ") - if type(o) == "number" or type(o) == "string" or type(o) == "boolean" - or type(o) == "function" or type(o) == "nil" - or type(o) == "userdata" then - io.write(basic_dump2(o), "\n") - elseif type(o) == "table" then - if dumped[o] then - io.write(dumped[o], "\n") - else - dumped[o] = name - io.write("{}\n") -- new table - for k,v in pairs(o) do - local fieldname = string.format("%s[%s]", name, basic_dump2(k)) - dump2(v, fieldname, dumped) - end - end - else - error("cannot dump a " .. type(o)) - return nil + if type(o) ~= "table" then + return string.format("%s = %s\n", name, basic_dump(o)) end + if dumped[o] then + return string.format("%s = %s\n", name, dumped[o]) + end + dumped[o] = name + -- This contains a list of strings to be concatenated later (because + -- Lua is slow at individual concatenation). + local t = {} + for k, v in pairs(o) do + local keyStr + if type(k) == "table" then + if dumped[k] then + keyStr = dumped[k] + else + -- Key tables don't have a name, so use one of + -- the form _G["table: 0xFFFFFFF"] + keyStr = string.format("_G[%q]", tostring(k)) + -- Dump key table + table.insert(t, dump2(k, keyStr, dumped)) + end + else + keyStr = basic_dump(k) + end + local vname = string.format("%s[%s]", name, keyStr) + table.insert(t, dump2(v, vname, dumped)) + end + return string.format("%s = {}\n%s", name, table.concat(t)) end -------------------------------------------------------------------------------- +-- This dumps values in a one-line format, like serialize(). +-- For example, {test = {"Testing..."}} becomes {["test"] = {[1] = "Testing..."}} +-- This supports tables as keys, but not circular references. +-- It performs poorly with multiple references as it writes out the full +-- table each time. +-- The dumped argument is internal-only. + function dump(o, dumped) + -- Same as "dumped" in dump2. The difference is that here it can only + -- contain boolean (and nil) values since multiple references aren't + -- handled properly. dumped = dumped or {} - if type(o) == "number" then - return tostring(o) - elseif type(o) == "string" then - return string.format("%q", o) - elseif type(o) == "table" then + if type(o) == "table" then if dumped[o] then return "" end dumped[o] = true local t = {} - for k,v in pairs(o) do - t[#t+1] = "[" .. dump(k, dumped) .. "] = " .. dump(v, dumped) + for k, v in pairs(o) do + k = dump(k, dumped) + v = dump(v, dumped) + table.insert(t, string.format("[%s] = %s", k, v)) end - return "{" .. table.concat(t, ", ") .. "}" - elseif type(o) == "boolean" then - return tostring(o) - elseif type(o) == "function" then - return "" - elseif type(o) == "userdata" then - return "" - elseif type(o) == "nil" then - return "nil" + return string.format("{%s}", table.concat(t, ", ")) else - error("cannot dump a " .. type(o)) - return nil + return basic_dump(o) end end diff --git a/builtin/common/serialize.lua b/builtin/common/serialize.lua index 6cb9470..1deee43 100644 --- a/builtin/common/serialize.lua +++ b/builtin/common/serialize.lua @@ -113,7 +113,7 @@ function core.serialize(x) elseif t=="string" then return string.format("%q", x) elseif t=="boolean" then return x and "true" or "false" elseif t=="function" then - return "loadstring("..string.format("%q", string.dump(x))..")" + return string.format("loadstring(%q)", string.dump(x)) elseif t=="table" then local acc = { } local idx_dumped = { }