libevent 多线程http服务器

libevent.cpp

#include <event.h>
#include <evhttp.h>
#include <pthread.h>
#include <errno.h>
#include <string.h>
#include <fcntl.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <iostream>
#include <ctime>
#include<fstream> 

using namespace std;

#define PORT 2500


////////////////////////////////////////////////////////////////////////////////////
/////////////////////////////http request handle process////////////////////////////
////////////////////////////////////////////////////////////////////////////////////
void http_handler(struct evhttp_request *req)
{
    struct evbuffer *buf;
    buf = evbuffer_new();
  
	
	struct evkeyvalq * postHead = req->input_headers;	
	
	const char *http_cId = evhttp_find_header(postHead, "contourType");	//解析head，根据key获取value
	
	/////////////////分析POST报文body信息/////////////////////
	int buffer_data_len;
	buffer_data_len = EVBUFFER_LENGTH(req->input_buffer);
	//printf("%d\n\n",buffer_data_len);
	/////////////////////////获得body信息/////////////////////////////////////////
	
	if(buffer_data_len == 0)
	{
		evhttp_add_header(req->output_headers,"error_status","no picture!");
		evbuffer_add_printf(buf,"no picture! please check your input");
	/////////////////////////////////////////////////////////////////////////////////
		//返回code 400
		evhttp_send_reply(req, 400, "Error", buf);  
		//释放内存  
		evbuffer_free(buf); 
		return;				
	
	}
	
	unsigned char *buffer_data = (unsigned char *)malloc(buffer_data_len+1);
	memset(buffer_data, '\0', buffer_data_len+1);
	
	memcpy (buffer_data, EVBUFFER_DATA(req->input_buffer), buffer_data_len);

	//cout<<"pic:"<<endl<<buffer_data<<endl;

	string resultURL = "thank you";
	cout<<"query end"<<endl;
    evbuffer_add_printf(buf, resultURL.c_str());
	evhttp_send_reply(req, HTTP_OK, "OK", buf);
	
	cout<<"search end"<<endl;
    // 输出
	evhttp_clear_headers(postHead);
    free(buffer_data);   
    evbuffer_free(buf);
}

///////////////////////////////////////////////////////////////////////////////////////////
/////////////////////////////////////////libevent//////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////////////////
namespace servers {
namespace util {

class HTTPServer {
public:
  HTTPServer() {}
  ~HTTPServer() {}
  int serv(int port, int nthreads);
protected:
  static void* Dispatch(void *arg);
  static void GenericHandler(struct evhttp_request *req, void *arg);
  void ProcessRequest(struct evhttp_request *request);
  int BindSocket(int port);
};

int HTTPServer::BindSocket(int port) {
  int r;
  int nfd;
  nfd = socket(AF_INET, SOCK_STREAM, 0);
  if (nfd < 0) return -1;

  int one = 1;
  r = setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, (char *)&one, sizeof(int));

  struct sockaddr_in addr;
  memset(&addr, 0, sizeof(addr));
  addr.sin_family = AF_INET;
  addr.sin_addr.s_addr = INADDR_ANY;
  addr.sin_port = htons(port);

  r = bind(nfd, (struct sockaddr*)&addr, sizeof(addr));
  if (r < 0) return -1;
  r = listen(nfd, 10240);
  if (r < 0) return -1;

  int flags;
  if ((flags = fcntl(nfd, F_GETFL, 0)) < 0
      || fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0)
    return -1;

  return nfd;
}

int HTTPServer::serv(int port, int nthreads) {
  int r;
  int nfd = BindSocket(port);
  if (nfd < 0) return -1;
  pthread_t ths[nthreads];
  for (int i = 0; i < nthreads; i++) {
    struct event_base *base = event_init();
    if (base == NULL) return -1;
    struct evhttp *httpd = evhttp_new(base);
    if (httpd == NULL) return -1;
    r = evhttp_accept_socket(httpd, nfd);
    if (r != 0) return -1;
	
	int timeout = 60;
	evhttp_set_timeout(httpd, timeout);
    evhttp_set_gencb(httpd, HTTPServer::GenericHandler, this);
    r = pthread_create(&ths[i], NULL, HTTPServer::Dispatch, base);
    if (r != 0) return -1;
  }
  for (int i = 0; i < nthreads; i++) {
    pthread_join(ths[i], NULL);
  }
}

void* HTTPServer::Dispatch(void *arg) {
  event_base_dispatch((struct event_base*)arg);
  return NULL;
}

void HTTPServer::GenericHandler(struct evhttp_request *req, void *arg) {
  ((HTTPServer*)arg)->ProcessRequest(req);
}

void HTTPServer::ProcessRequest(struct evhttp_request *req) {
  http_handler(req);
}

}
}

int main(int argv,char*argc[]){

	servers::util::HTTPServer s;
	s.serv(PORT, 10);
}