lua语言三则特性

do arrayData = {"a", "b", "c", "d", "e"}; function pack(...) return {...}; end print( pack("aa", "bb")[2] ); --print((returnMoreValues())); --print(arrayData); -- print the address of the arrayData --print(unpack(arrayData)); -- print all the elements of the arrayData print(unpack(arrayData, 2)); --the second param is the index of the arrayData end >lua -e "io.stdout:setvbuf 'no'" "luatest.lua" b c d e >Exit code: 0 >lua -e "io.stdout:setvbuf 'no'" "luatest.lua" aa b c d e >Exit code: 0 >lua -e "io.stdout:setvbuf 'no'" "luatest.lua" bb b c d e >Exit code: 0

序列化加密

string.dump(loadstring(ret))

这就是加密的代码，因为

string.dump

参数必须是

function

, 所以使用

loadstring

将字符串加载成chunk,然后在由

string.dump

导成字节码
其实就是使用了

string.dump

函数，它可以把

function

导成二进制字节码，使用它处理一下就可以把明文字符串转成字节码了

local function ser(var, enc)
assert(type(var)=="table")
-- 标记所有出现的table, 并记录其key, 用于处理循环引用
local mark = {}
-- 用于记录循环引用的赋值语句
local assign = {}
-- 序列化表, ret字符串必须与后面的loca ret=%s中的ret相同，因为这个ret可能也会组织到结果字符串中。
local ret = table_ser(var, "ret", mark, assign)
local ret = string.format("local ret=%s %s return ret", ret, table.concat(assign, ";"))
return (enc==nil or enc==true) and string.dump(loadstring(ret)) or ret
end

void luaL_register (lua_State *L,
const char *libname,
const luaL_Reg *l);

Opens a library.
When called with

libname

equal to

NULL

, it simply registers all functions in the list

l

(see

luaL_Reg

) into the table on the top of the stack.
When called with a non-null

libname

,

luaL_register

creates a new table

t

, sets it as the value of the global variable

libname

, sets it as the value of

package.loaded[libname]

, and registers on it all functions in the list

l

. If there is a table in

package.loaded[libname]

or in variable

libname

, reuses this table instead of creating a new one.
In any case the function leaves the table on the top of the stack.

package.loaded[libname]

libname