// HTTP client for testing high connection concurrency
// Authors: Richard Jones and Rasmus Andersson
// Released in the public domain. No restrictions, no support.

// SEE:
// http://rsms.me/2009/10/05/10k-comet-connections.html

#include <sys/types.h>
#include <sys/time.h>
#include <sys/queue.h>
#include <stdlib.h>
#include <err.h>
#include <event.h>
#include <evhttp.h>
#include <unistd.h>
#include <stdio.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <time.h>
#include <pthread.h>
 
#define BUFSIZE 4096
#define SLEEP_MS 10

// options
int num_conns = 100;

// state
int bytes_recvd = 0;
int chunks_recvd = 0;
int closed = 0;
int connected = 0;
int max_concurrency = 0;
int responses_completed_ok = 0;

// misc
char buf[BUFSIZE];
 
// called per chunk received
void chunkcb(struct evhttp_request * req, void * arg) {
	//int s = evbuffer_remove( req->input_buffer, &buf, BUFSIZE );
  // printf("Read %d bytes: %s\n", s, &buf);
	//bytes_recvd += s;
	chunks_recvd++;
}
 
// gets called when request completes
void reqcb(struct evhttp_request * req, void * arg) {
	int s = evbuffer_remove( req->input_buffer, &buf, BUFSIZE );
	bytes_recvd += s;
	chunks_recvd++;
	
	if (connected-closed > max_concurrency)
		max_concurrency = connected-closed;
	
	responses_completed_ok++;
	closed++;
}
 
int main(int argc, char * const *argv) {
	event_init();
	struct evhttp_connection *evhttp_connection;
	struct evhttp_request *evhttp_request;
	//char addr[16];
	const char *remote_addr = "65.50.201.133";
	int remote_port = 80;
	const char *uri = "/";
	
	if (argc > 1 && (strcmp(argv[1], "-h") == 0 || strcmp(argv[1], "--help") == 0)) {
		fprintf(stderr, "%s [connections[ address[ port[ uri]]]]\n", argv[0]);
		return 1;
	}
	
	if (argc > 1) num_conns = atoi(argv[1]);
	if (argc > 2) remote_addr = argv[2];
	if (argc > 3) remote_port = atoi(argv[3]);
	if (argc > 4) uri = argv[4];
	
	if (num_conns > 65536) {
		// see http://www.mail-archive.com/libevent-users@monkey.org/msg01302.html
		// evhttp_connection_set_local_address can be used to send from different
		// local addresses.
		fprintf(stderr, "%s: connection count too high (>65536)\n", argv[0]);
		exit(1);
	}
	
	printf("Making %d connections to http://%s:%d%s\n", num_conns, remote_addr, remote_port, uri);
	
	int i;
	
	for (i=1;i<=num_conns;i++) {
		evhttp_connection = evhttp_connection_new(remote_addr, remote_port);
		evhttp_set_timeout((struct evhttp *)evhttp_connection, 864000); // 10 day timeout
		evhttp_request = evhttp_request_new(reqcb, NULL);
		evhttp_request->chunk_cb = chunkcb;
		evhttp_add_header(evhttp_request->output_headers, "Host", "hunch.se");
		evhttp_add_header(evhttp_request->output_headers, "Connection", "close");
		evhttp_make_request(evhttp_connection, evhttp_request, EVHTTP_REQ_GET, uri);
		connected++;
		if ( i % 100 == 0) {
			printf("%d requests sent (%d connected)\n", i, connected-closed);
		}
		evhttp_connection_set_timeout(evhttp_request->evcon, 864000);
		event_loop( EVLOOP_NONBLOCK );
		
    // pause between looping?
    // usleep(SLEEP_MS*1000);
	}
	
	printf("All %d requests sent (%d connected).\n", num_conns, connected);
	
	event_dispatch();
	
	printf("All connections are closed.\n");
	printf("connections: %d\tBytes: %d\tChunks: %d\tClosed: %d\n", num_conns, bytes_recvd, chunks_recvd, closed);
	printf("Completed: %d\tFailed: %d\n", responses_completed_ok, num_conns-chunks_recvd);
	printf("Max concurrency: %d\n", max_concurrency);
	
	return 0;
}

// on mac osx
// brew install libevent
// export CC=/usr/bin/gcc; gcc -o c10k-test-client -levent -I/usr/local/Cellar/libevent/ -L/usr/local/Cellar/libevent/ c10k-test-client.c
// 

//   originally was: gcc -o floodtest -levent -I/opt/local/include -L/opt/local/lib floodtest.c