#include <inttypes.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <uv.h>

Classes
struct	child_worker

Functions
void	close_process_handle (uv_process_t *req, int64_t exit_status, int term_signal)

void	alloc_buffer (uv_handle_t handle, size_t suggested_size, uv_buf_t buf)

void	on_new_connection (uv_stream_t *server, int status)

void	setup_workers ()

int	main ()

Variables
uv_loop_t *	loop

struct child_worker *	workers

int	round_robin_counter

int	child_worker_count

uv_buf_t	dummy_buf

char	worker_path [500]

Function Documentation

◆ alloc_buffer()

void alloc_buffer	(	uv_handle_t *	handle,
		size_t	suggested_size,
		uv_buf_t *	buf
	)

Definition at line 26 of file main.c.

                                                                              {
   buf->base = malloc(suggested_size);
   buf->len = suggested_size;
 }

References malloc().

◆ close_process_handle()

void close_process_handle	(	uv_process_t *	req,
		int64_t	exit_status,
		int	term_signal
	)

Definition at line 21 of file main.c.

                                                                                    {
     fprintf(stderr, "Process exited with status %" PRId64 ", signal %d\n", exit_status, term_signal);
     uv_close((uv_handle_t*) req, NULL);
 }

References exit_status, NULL, PRId64, req, and uv_close().

Referenced by setup_workers().

◆ main()

int main ( void )

Definition at line 97 of file main.c.

            {
     loop = uv_default_loop();
  
     setup_workers();
  
     uv_tcp_t server;
     uv_tcp_init(loop, &server);
  
     struct sockaddr_in bind_addr;
     uv_ip4_addr("0.0.0.0", 7000, &bind_addr);
     uv_tcp_bind(&server, (const struct sockaddr *)&bind_addr, 0);
     int r;
     if ((r = uv_listen((uv_stream_t*) &server, 128, on_new_connection))) {
         fprintf(stderr, "Listen error %s\n", uv_err_name(r));
         return 2;
     }
     return uv_run(loop, UV_RUN_DEFAULT);
 }

References loop, on_new_connection(), r, setup_workers(), uv_default_loop(), uv_err_name(), uv_ip4_addr(), uv_listen(), uv_run(), UV_RUN_DEFAULT, uv_tcp_bind(), and uv_tcp_init().

◆ on_new_connection()

void on_new_connection	(	uv_stream_t *	server,
		int	status
	)

Definition at line 31 of file main.c.

                                                         {
     if (status == -1) {
         // error!
         return;
     }
  
     uv_tcp_t *client = (uv_tcp_t*) malloc(sizeof(uv_tcp_t));
     uv_tcp_init(loop, client);
     if (uv_accept(server, (uv_stream_t*) client) == 0) {
         uv_write_t *write_req = (uv_write_t*) malloc(sizeof(uv_write_t));
         dummy_buf = uv_buf_init("a", 1);
         struct child_worker *worker = &workers[round_robin_counter];
         uv_write2(write_req, (uv_stream_t*) &worker->pipe, &dummy_buf, 1, (uv_stream_t*) client, NULL);
         round_robin_counter = (round_robin_counter + 1) % child_worker_count;
     }
     else {
         uv_close((uv_handle_t*) client, NULL);
     }
 }

References child_worker_count, dummy_buf, loop, malloc(), NULL, round_robin_counter, status, uv_accept(), uv_buf_init(), uv_close(), uv_tcp_init(), uv_write2(), worker(), workers, and write_req.

◆ setup_workers()

void setup_workers ( )

Definition at line 51 of file main.c.

                      {
     size_t path_size = 500;
     uv_exepath(worker_path, &path_size);
     strcpy(worker_path + (strlen(worker_path) - strlen("multi-echo-server")), "worker");
     fprintf(stderr, "Worker path: %s\n", worker_path);
  
     char* args[2];
     args[0] = worker_path;
     args[1] = NULL;
  
     round_robin_counter = 0;
  
     // ...
  
     // launch same number of workers as number of CPUs
     uv_cpu_info_t *info;
     int cpu_count;
     uv_cpu_info(&info, &cpu_count);
     uv_free_cpu_info(info, cpu_count);
  
     child_worker_count = cpu_count;
  
     workers = calloc(cpu_count, sizeof(struct child_worker));
     while (cpu_count--) {
         struct child_worker *worker = &workers[cpu_count];
         uv_pipe_init(loop, &worker->pipe, 1);
  
         uv_stdio_container_t child_stdio[3];
         child_stdio[0].flags = UV_CREATE_PIPE | UV_READABLE_PIPE;
         child_stdio[0].data.stream = (uv_stream_t*) &worker->pipe;
         child_stdio[1].flags = UV_IGNORE;
         child_stdio[2].flags = UV_INHERIT_FD;
         child_stdio[2].data.fd = 2;
  
         worker->options.stdio = child_stdio;
         worker->options.stdio_count = 3;
  
         worker->options.exit_cb = close_process_handle;
         worker->options.file = args[0];
         worker->options.args = args;
  
         uv_spawn(loop, &worker->req, &worker->options); 
         fprintf(stderr, "Started worker %d\n", worker->req.pid);
     }
 }