Resolve problems that is met in CentOS7. (#5738)

* Set value for std with c99 to avoid compile error on CentOS7.

* Get parameter from stack by same sequence.

* Add performance test.

tests/examples/lua/README.md

@@ -19,6 +19,10 @@ Run lua sample:
 lua test.lua
 ```
 
+## Run performance test:
+```
+time lua benchmark.lua
+```
 ## OpenResty Dependencies
 - OpenResty: 
 ```

tests/examples/lua/benchmark.lua

+local driver = require "luaconnector"
+
+local config = {
+   password = "taosdata",
+   host = "127.0.0.1",
+   port = 6030,
+   database = "",
+   user = "root",
+
+   max_packet_size = 1024 * 1024 
+}
+
+local conn
+local res = driver.connect(config)
+if res.code ~=0 then
+   print("connect--- failed: "..res.error)
+   return
+else
+   conn = res.conn
+   print("connect--- pass.")
+end
+
+local res = driver.query(conn,"drop database if exists demo")
+
+res = driver.query(conn,"create database demo")
+if res.code ~=0 then
+   print("create db--- failed: "..res.error)
+   return
+else
+   print("create db--- pass.")
+end
+
+res = driver.query(conn,"use demo")
+if res.code ~=0 then
+   print("select db--- failed: "..res.error)
+   return
+else
+   print("select db--- pass.")
+end
+
+res = driver.query(conn,"create table m1 (ts timestamp, speed int,owner binary(20))")
+if res.code ~=0 then
+   print("create table---failed: "..res.error)
+   return
+else
+   print("create table--- pass.")
+end
+
+local base = 1617330000000
+local index =0
+local count = 100000
+local t
+while( index < count )
+do
+   t = base + index
+  local q=string.format([[insert into m1 values (%d,0,'robotspace')]],t)
+res = driver.query(conn,q)
+if res.code ~=0 then
+   print("insert records failed: "..res.error)
+   return
+else
+
+end
+   index = index+1
+end
+print(string.format([["Done. %d records has been stored."]],count))
+driver.close(conn)

tests/examples/lua/build.sh

-gcc lua_connector.c -fPIC -shared -o luaconnector.so -Wall -ltaos
+gcc -std=c99 lua_connector.c -fPIC -shared -o luaconnector.so -Wall -ltaos
 

tests/examples/lua/lua51/build.sh

-gcc lua_connector51.c -fPIC -shared -o luaconnector51.so -Wall -ltaos
+gcc -std=c99 lua_connector51.c -fPIC -shared -o luaconnector51.so -Wall -ltaos
 

tests/examples/lua/lua_connector.c

@@ -23,7 +23,7 @@ static int l_connect(lua_State *L){
 
   luaL_checktype(L, 1, LUA_TTABLE);
 
-  lua_getfield(L,-1,"host");
+  lua_getfield(L,1,"host");
   if (lua_isstring(L,-1)){
     host = lua_tostring(L, -1);
     // printf("host = %s\n", host);