http server in c

server.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#define PORT 80

int sockfd;
struct sockaddr_in sockaddr;

void die(char *message) {
  perror(message);
  exit(EXIT_FAILURE);
}

void set_socket_reuse() {
  int optval = 1;
  setsockopt(sockfd, SOL_SOCKET, SO_REUSEPORT, &optval, sizeof(optval));
  setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &optval, sizeof(optval));
}

void init_socket() {
  sockfd = socket(AF_INET, SOCK_STREAM, 0);
  if (sockfd == -1) {
    perror("socket");
    exit(EXIT_FAILURE);
  }

  sockaddr.sin_addr.s_addr = inet_addr("127.0.0.1");
  sockaddr.sin_port = htons(PORT);
  sockaddr.sin_family = AF_INET;

  int err = bind(sockfd, (struct sockaddr *)&sockaddr, sizeof(sockaddr));
  if (err == -1) {
    die("bind");
  }

  err = listen(sockfd, 5);
  if (err == -1) {
    die("listen");
  }
  printf("server running on port: %d\n\n", PORT);
}

void handle_con() {
  while (1) {
    int clientfd = accept(sockfd, NULL, NULL);
    if (clientfd == -1) {
      die("accept");
    }

    char buf[1024];
    while (1) {
      // read request
      memset(buf, '\0', sizeof(buf));
      int err = read(clientfd, buf, sizeof(buf));
      if (err <= 0) {
        break;
      }
      printf("%s\n", buf);

      // write response
      memset(buf, '\0', sizeof(buf));
      strcpy(buf,
          "HTTP/1.1 200 OK\r\n"
          "Content-Type: text/plain\r\n"
          "Content-Length: 5\r\n"
          "Connection: close\r\n"
          "\r\n"
          "hello"
          );
      write(clientfd, buf, strlen(buf));
      printf("%s\n", buf);
      close(clientfd);
    }
  }
}

int main() {
  init_socket();
  set_socket_reuse();
  handle_con();

  close(sockfd);

  return 0;
}