怎样利用C语言实现最简单的HTTP服务器详解

<h1>Hello!</h1>

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

#define PORT 8888
#define BUFFER_SIZE 4096
#define RESPONSE_HEADER "HTTP/1.1 200 OK\r\nConnection: close\r\nAccept-Ranges: bytes\r\nContent-Type: text/html\r\n\r\n"
#define RESPONSE_BODY "<h1>Hello!</h1>"

int handle(int conn){
  int len = 0;
  char buffer[BUFFER_SIZE];
  char *pos = buffer;
  bzero(buffer, BUFFER_SIZE);
  len = recv(conn, buffer, BUFFER_SIZE, 0);
  if (len <= 0 ) {
    printf ("recv error");
    return -1;
  } else {
    printf("Debug request:\n--------------\n%s\n\n",buffer);
  }

  send(conn, RESPONSE_HEADER RESPONSE_BODY, sizeof(RESPONSE_HEADER RESPONSE_BODY), 0);
  close(conn);//关闭连接
}

int main(int argc,char *argv[]){
  int port = PORT;
  struct sockaddr_in client_sockaddr;   
  struct sockaddr_in server_sockaddr;
  int listenfd = socket(AF_INET,SOCK_STREAM,0);
  int opt = 1; 
  int conn;
  socklen_t length = sizeof(struct sockaddr_in);
  setsockopt(listenfd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(int));
  server_sockaddr.sin_family = AF_INET;
  server_sockaddr.sin_port = htons(port);
  server_sockaddr.sin_addr.s_addr = htonl(INADDR_ANY);

  if(bind(listenfd,(struct sockaddr *)&server_sockaddr,sizeof(server_sockaddr))==-1){
    printf("bind error!\n");
    return -1;  
  } 

  if(listen(listenfd, 10) < 0) {
    printf("listen failed!\n");
    return -1;  
  }

  while(1){
    conn = accept(listenfd, (struct sockaddr*)&client_sockaddr, &length);
    if(conn < 0){
      printf("connect error!\n");
      continue;
    }
    if (handle(conn) < 0) {
      printf("connect error!\n");
      close(conn);
      continue;
    } 
  }
  return 0;
}