tdcan/test/sender.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <unistd.h>

#define SOCKET_PATH "/tmp/unix_dgram_demo"
#define SENDER_PATH "/tmp/unix_dgram_sender"

int main() {
  int                sock_fd;
  struct sockaddr_un server_addr, client_addr;
  char               buffer[256];

  // Create socket
  sock_fd = socket(AF_UNIX, SOCK_DGRAM, 0);
  if (sock_fd == -1) {
    perror("socket");
    exit(EXIT_FAILURE);
  }

  // Configure client address (we need to bind to send/receive)
  memset(&client_addr, 0, sizeof(client_addr));
  client_addr.sun_family = AF_UNIX;
  strncpy(client_addr.sun_path, SENDER_PATH, sizeof(client_addr.sun_path) - 1);

  // Remove socket file if it already exists
  unlink(SENDER_PATH);

  // Bind to our own address (required for receiving response)
  if (bind(sock_fd, (struct sockaddr *)&client_addr, sizeof(client_addr)) == -1) {
    perror("bind");
    close(sock_fd);
    exit(EXIT_FAILURE);
  }

  // Configure server address
  memset(&server_addr, 0, sizeof(server_addr));
  server_addr.sun_family = AF_UNIX;
  strncpy(server_addr.sun_path, SOCKET_PATH, sizeof(server_addr.sun_path) - 1);

  // Send message to server
  char txbuf[10240] = {0};
  for (int i = 0; i < sizeof(txbuf) - 1; i++) {
    txbuf[i] = 'a' + (i % 26);  // Fill with a-z characters
  }

  while (1) {
    if (sendto(sock_fd, txbuf, 10240, 0, (struct sockaddr *)&server_addr, sizeof(server_addr)) == -1) {
      perror("sendto");
      close(sock_fd);
      exit(EXIT_FAILURE);
    }
  }

  printf("Message sent to receiver.\n");

  // Receive response
  socklen_t server_len = sizeof(server_addr);
  ssize_t   num_bytes  = recvfrom(sock_fd, buffer, sizeof(buffer) - 1, 0, (struct sockaddr *)&server_addr, &server_len);
  if (num_bytes == -1) {
    perror("recvfrom");
  } else {
    buffer[num_bytes] = '\0';
    printf("Received response: %s\n", buffer);
  }

  // Clean up
  close(sock_fd);
  unlink(SENDER_PATH);

  return 0;
}