/*
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 */
 
#include <arpa/inet.h>
#include <linux/if_packet.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <net/if.h>
#include <netinet/ether.h>
#include <sys/sendfile.h>
#include <errno.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <netinet/in.h>
#define _GNU_SOURCE         /* See feature_test_macros(7) */
#include <fcntl.h>
#include <sys/uio.h>
#include <netinet/tcp.h>

#define ETH_P_IP	0x0800		/* Internet Protocol packet	*/
#define ETH_ALEN	6		/* from <net/ethernet.h> */
#define ETH_P_ALL       0x0003

#define MY_DEST_MAC0	0xba
#define MY_DEST_MAC1	0xf6
#define MY_DEST_MAC2	0xb1
#define MY_DEST_MAC3	0x71
#define MY_DEST_MAC4	0x09
#define MY_DEST_MAC5	0x64
 
#define DEFAULT_IF	"wlan0"
#define BUF_SIZ		8192
 
int main(int argc, char *argv[])
{
	int sockfd, listenfd;
	socklen_t clilen;
	struct ifreq if_idx;
	struct ifreq if_mac;
	int tx_len = 0;
	char sendbuf[BUF_SIZ];
	struct ether_header *eh = (struct ether_header *) sendbuf;
	struct iphdr *iph = (struct iphdr *) (sendbuf + sizeof(struct ether_header));
	struct sockaddr_ll socket_address;
	char ifName[IFNAMSIZ];
	int i, j, ret=0, sendsize=1488, packet_num, offset = 0, port = 4445;
	int fd;                    /* file descriptor for file to send */
	int outstanding;
	struct timeval t_start,t_end;
	ssize_t bytes, bytes_sent, bytes_in_pipe;
	size_t total_bytes_sent = 0;
	
    struct sockaddr_in servaddr,cliaddr;

	
    int filedes [2];
    ret = pipe (filedes);
    
    if (argc > 1)
		packet_num = atoi(argv[1]);
	else
		packet_num = 166666*sendsize;
    
	if (argc > 2)
		port = atoi(argv[2]);
	
    //sockfd = socket(AF_INET, SOCK_STREAM, 0);
    //bzero(&servaddr,sizeof(servaddr));
    //servaddr.sin_family = AF_INET;
    //servaddr.sin_addr.s_addr=inet_addr("128.111.68.220");
    //servaddr.sin_port=htons(4444);
    
    sockfd = socket(AF_INET, SOCK_STREAM, 0);

    bzero(&servaddr,sizeof(servaddr));
    servaddr.sin_family = AF_INET;
    servaddr.sin_addr.s_addr=inet_addr("128.111.68.220");
    servaddr.sin_port=htons(port);


    fd = open("/data/local/tmp/bigfile_w", O_WRONLY | O_CREAT | O_TRUNC);
    if (fd == -1) {
        fprintf(stderr, "unable to open the file.\n");
        exit(1);
    }
    
    //setsockopt(sockfd, IPPROTO_TCP, TCP_NODELAY, (char *) &ret, sizeof(int)); 
   	//ioctl(sockfd, SIOCOUTQ, &outstanding);
   	//printf("outstanding:%d\n", outstanding);
   
	gettimeofday(&t_start, NULL);
	if (connect(sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr)) < 0)
    {
        fprintf(stderr, "unable to connect the server.\n");
        exit(1);
    }
    while (total_bytes_sent < packet_num)
    {
        // Splice the data from in_fd into the pipe
        if ((bytes_sent = splice(sockfd, NULL, filedes[1], NULL,
                4096, 
                SPLICE_F_MORE | SPLICE_F_MOVE)) <= 0) {
            if (errno == EINTR || errno == EAGAIN) {
                // Interrupted system call/try again
                // Just skip to the top of the loop and try again
				printf("in error: %d\n", bytes_sent);
				fflush(stdout);
				usleep(100);
                continue;
            }
            perror("splice");
            return -1;
        }

		//printf("%d\n", bytes_sent);
		//fflush(stdout);
		
		
        // Splice the data from the pipe into out_fd
        bytes_in_pipe = bytes_sent;
        while (bytes_in_pipe > 0) {
            if ((bytes = splice(filedes[0], NULL, fd, NULL, bytes_in_pipe,
                    SPLICE_F_MORE | SPLICE_F_MOVE)) <= 0) {
                if (errno == EINTR || errno == EAGAIN) {
                    // Interrupted system call/try again
                    // Just skip to the top of the loop and try again
					printf("out error: %d\n", bytes_sent);
					fflush(stdout);
                    continue;
                }
                perror("splice");
                return -1;
            }
            bytes_in_pipe -= bytes;
        }
		
		//printf("%d, %d\n", bytes_sent, total_bytes_sent);
		//fflush(stdout);
		
        total_bytes_sent += bytes_sent;
        
        /*
        for(;;)
        {
			ioctl(sockfd, SIOCOUTQ, &outstanding);
			printf("outstanding:%d\n", outstanding);
			if (outstanding>0)
			{
				usleep(100);
			}
			else
			{
				break;
			}
		}
        */
        
        //ret = splice (fd, (off64_t *)&offset, filedes[1], NULL, sendsize, SPLICE_F_MORE | SPLICE_F_MOVE);
        //ret = sendfile(sockfd, fd, (off_t *)&offset, sendsize);
        //offset += total_bytes_sent;
        //printf("sent:%d, total:%d\n", bytes_sent, total_bytes_sent);
    }
    close(sockfd);
    gettimeofday(&t_end, NULL);
    printf("%lf\n", (t_end.tv_sec-t_start.tv_sec)*1000.0+(t_end.tv_usec-t_start.tv_usec)/1000.0);
    
    close(fd);
    
	return 0;
}