Table overflow problem in openresty by ffi calling C function

[lan hust]

Dear all and Yichun Zhang (agentzh),

      I have read the discussion about Calling C function in openresty by ffi module, and report table overflow in https://groups.google.com/g/openresty-en/c/I5Vax1jDIsM.

and with your suggestions, i fix my lua code by writing new lua module , but it still report table overflow, i don't understand why, please help me ,thank a lot.

below is my lua code:

openresty lua:

nginx.conf:

...

location ~ ^/(cdnlog|livertmp) {

default_type 'text/html';

access_by_lua_file conf/lua/cdnlog.lua;

proxy_pass http://$http_host$request_uri;

}

...

cdnlog.lua:

...

attr= require("attr_api")

function check_request_k(key)

attr.attr_api(12345, 1)

end

check_request_k(ngx.req.get_uri_args()['k'])

...

attr_api.lua

local ffi = require "ffi"

local _M = { _VERSION = "0.1" }

ffi.cdef[[
    int Attr_API(int attr, int iValue);            
]]

local myffi = ffi.load("/usr/servers/nginx/conf/lua/libAttr_API.so")

function _M.attr_api(id, value)
    if not myffi or not myffi.Attr_API then
        ngx.log(ngx.ERR, "Load attr_api failed: ", err)
        return
    end
    local ok, err = pcall(myffi.Attr_API, id, value)
    if not ok then
        ngx.log(ngx.ERR, "Attr_API call failed: ", err)
    end
end

return _M

this lib (/usr/servers/nginx/conf/lua/libAttr_API.so) is not problem, the Attr_API function work correctly.

but after running one day, it report:
2025/04/26 06:43:53 [error] 34231#0: *439920047 lua entry thread aborted: runtime error: table overflow

stack traceback:
coroutine 0:
        [C]: in function 'cdef'

[Junlong li]

you can give a minimal example that can reproduce this issue.

[lan hust]

i make a simple test for more times ,it dosn't appear and works correctly , surprising

file  main.lua:
local attr= require("attr_api")
local times=1000000000
local a = 0
while a < times do
    attr.attr_api(33712153 , 1)
    a = a+1
end
print("finish:", a)



file attr_api.lua:

local ffi = require "ffi"

local _M = { _VERSION = "0.1" }

ffi.cdef[[
    int Attr_API(int attr, int iValue);            
]]

local myffi = ffi.load("/usr/servers/nginx/conf/lua/libAttr_API.so", global)

function _M.attr_api(id, value)
    if not myffi or not myffi.Attr_API then

        print("Load attr_api failed: ")

        return
    end
    local ok, err = pcall(myffi.Attr_API, id, value)
    if not ok then

        print("Attr_API call failed: ", err)
    end
end

return _M

lan hust <hustl...@gmail.com> 于2025年4月26日周六 16:36写道：

Junlong li <zhuizhu...@gmail.com> 于2025年4月26日周六 17:47写道：

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