How to Share libuv Event Loop Between Luvi and a Custom C Dynamic Library

[t59688]

Hi Luvi

I'm building a custom C dynamic library that I want to integrate with Luvi. My library uses libuv for asynchronous operations, and I want to ensure that it shares the same libuv event loop as Luvi to avoid conflicts and resource duplication.

Here's a simplified version of my C code:

#include <uv.h>
#include <stdlib.h>
#include <string.h>
#include <pthread.h>
#include <unistd.h>

static uv_async_t *luvi_async = NULL;
static char *message = NULL;

typedef struct
{
    char *data;
} async_data_t;

void *thread_func(void *arg)
{
    // Wait for 1 second
    sleep(1);

    // Set the message
    if (message)
    {
        free(message);
    }
    message = strdup("Hello from thread!");

    // Send an async event
    if (luvi_async)
    {
        printf("Sending async event\n");
        uv_async_send(luvi_async);
    }

    return NULL;
}

void xx_init(void *async)
{
    luvi_async = (uv_async_t *)async; // Store the uv_async_t*
}

void xx_do_something()
{
    pthread_t tid;

    // Create a thread that sends an async event after 1 second
    if (pthread_create(&tid, NULL, thread_func, NULL) != 0)
    {
        fprintf(stderr, "Failed to create thread\n");
        return;
    }

    // Detach the thread
    pthread_detach(tid);
}

// Function to get the message, callable from Lua
const char *xx_get_message()
{
    return message ? message : "";
}

and lua code

local uv = require('uv')
local ffi = require('ffi')

ffi.cdef [[
    void xx_init(void *async);
    void xx_do_something();
    const char *xx_get_message();
]]
local lccu = ffi.load('/cmake-build/lccu/liblccu.so')

local global_async = uv.new_async(function()
    print("Async callback triggered!")
end)

lccu.xx_init(global_async) -- 传递 uv_async_t*
lccu.xx_do_something()

uv.run()

My main question is: How can I ensure that my dynamic library and Luvi link to the same libuv library and share the same event loop instance?

I'm looking for guidance on:

• The correct way to compile and link my dynamic library with Luvi.
• Any necessary runtime configurations to ensure that both use the same libuv instance.
• Best practices for passing the uv_async_t handle from Luvi to my C library.
• I'm compiling Luvi from source.

Any help or pointers would be greatly appreciated!

Thank you.