void main()
{
while(1)
{
init_NRF24L01();
CE=1;
NRF24L01_TxPacket(Txbuf);
Delay_ms(10);
check_ACK();//发送应答信号检测，LED闪烁标志发送成功
}
}
int main(int argc, char * argv[]){
//first, check the number of argument
if (argc != 2){
printf("Usage: serveur.exe <port number>\n");
exit(1);
}
//trap SIGINT
signal(SIGINT,SIGINT_handler);
//variable definition
int sock_Data, addr_len,pid, seq, cwnd,normal_wnd, advanced_wnd;
int test =-1;
int SEG_SIZE,size,inc,descriptorToCheck[2];
int reuse = 1;
int ctrlBuff_SIZE = 12;
int isSYN=0;
int seq_advanced, seq_expected,checkBreak=0;
char SYN_ACK[12];
char FIN[4]="FIN";
char ctrlBuffer[ctrlBuff_SIZE];
char * dataBuffer;
FILE * file;
DATA DATA = NULL;
struct timeval ZERO = {0, 0};
// struct sockaddr_in
SOCKADDR_IN * my_addr_UDP;//Adress for listening UDP
SOCKADDR_IN * my_client_addr;//Adress client, for control
SOCKADDR_IN * data_addr;//Adress client for Data
int port_nb = atoi(argv[1]);
int sock_Control= mySocket(AF_INET,SOCK_DGRAM,0); //socketUDP
//display the descriptor value and pid of server
printf("Id Socket: %i\n",sock_Control);
printf("PID father: %i\n",getpid());
//allow to reuse immediately the socket
setsockopt( sock_Control, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof(reuse));
// structure sockaddr_in initialization
my_addr_UDP = conf_sock_addr(AF_INET, port_nb, "0.0.0.0");
my_client_addr = init_sock_addr();
size = sizeof(*my_client_addr);
//link the socket to the structure
myBind(sock_Control,my_addr_UDP,sizeof(*my_addr_UDP));
descriptorToCheck[0] = sock_Control;
//init fd set
fd_set * my_read_set = init_fd_set();
//loop to be a daemon
while (isSIGINT==0){
//set the fd_set
set_fd_set(my_read_set,descriptorToCheck[0]);
select(sock_Control+1,my_read_set,NULL,NULL,&ZERO);
if ( FD_ISSET(sock_Control, my_read_set) ){
// message reception
myReceiveFrom(sock_Control, ctrlBuffer, ctrlBuff_SIZE,my_client_addr,&size);
printf("Reception UDP by %d: %s\n",getpid(),ctrlBuffer);
// if message of type SYN
if ( check_SYN(ctrlBuffer) == 1){
port_nb= (port_nb+1)%8975+1025 ;
sprintf(SYN_ACK,"SYN-ACK%04d",port_nb);
//new socket for receiving data
sock_Data = mySocket(AF_INET,SOCK_DGRAM,0);
data_addr = conf_sock_addr(AF_INET, port_nb, "0.0.0.0");
addr_len = sizeof(* data_addr);
descriptorToCheck[1]=sock_Data;
//binding sock on addr client
myBind(sock_Data,data_addr,addr_len);
printf("Connexion Asked by client, dialoguing on port %d \n", ntohs(data_addr->sin_port));
printf("Adresse client %s\n",inet_ntoa(my_client_addr->sin_addr));
data_addr = conf_sock_addr(AF_INET, port_nb, inet_ntoa(my_client_addr->sin_addr));
// variable for receiving
SEG_SIZE= getMTU(data_addr)-28; // (MTU - header UDP + header IP)
SEG_SIZE=(SEG_SIZE> 5000)?5000:SEG_SIZE;
dataBuffer = (char *)malloc(SEG_SIZE*sizeof(char));
isSYN=1;
mySendTo(sock_Control, SYN_ACK,12,my_client_addr);
}
if ( check_ACK(ctrlBuffer) == 1 && isSYN ==1){
printf("Connexion Accept\n");
isSYN = 0;
//a little fork
pid = fork();
//if error
if (pid == -1){
perror("Fork Error\n");
exit(-1);
}
/*======================================================================================*/
/*===================================== child code =====================================*/
/*======================================================================================*/
else if (pid == 0){
myClose(sock_Control);
// reception of file name
myReceiveFrom(sock_Data,dataBuffer, SEG_SIZE,data_addr,&addr_len);
printf("Client Asking for file %s\n",dataBuffer);
//retrieve file name
file=myOpen(dataBuffer,"r");
seq=1, seq_advanced=1, cwnd =400,normal_wnd=320, advanced_wnd=cwnd-normal_wnd;
//while something to send, send and wait for ack
do {
checkBreak=0;
seq_expected=(seq == seq_advanced)?seq+cwnd:seq_advanced+advanced_wnd;
printf("seq :%d, seq_expected %d, seq_advanced %d\n",seq, seq_expected, seq_advanced);
//construct DATA to send from file
if (test == -1) test= readFileToBUFFER(file,&DATA,seq,(seq+cwnd==seq_expected)?cwnd:seq_advanced-seq+advanced_wnd,SEG_SIZE);
else readFileToBUFFER(file,&DATA,seq,test-seq,SEG_SIZE);
//send dataBuffer to client
if(seq+normal_wnd==seq_expected || seq == 1) {
sendData(sock_Data, cwnd, DATA, data_addr);
}else{
printf("fast retransmit, resend sequence presumed lost\n");
sendData(sock_Data, normal_wnd, DATA, data_addr);
printf("fast retransmit, send selected data\n");
sendSelectedData(sock_Data,seq_advanced,advanced_wnd,DATA,data_addr);
}
//while there is something to read
set_fd_set(my_read_set, descriptorToCheck[1]);
select(sock_Data + 1, my_read_set, NULL, NULL, &ZERO);
while (FD_ISSET(sock_Data,my_read_set) ) {
//reception
myReceiveFrom(sock_Data, ctrlBuffer, ctrlBuff_SIZE, data_addr, &addr_len);
//number of sequences acknowledged, (-1 si duplicate ACK)
inc = check_ACK_Seq(seq,cwnd,ctrlBuffer);
if (inc == -1) // if duplicate ACK
{
printf("ACK Duplicate ");
sendSelectedData(sock_Data,seq,1,DATA,data_addr);
if (checkBreak==0){
usleep(100000);
checkBreak=1;
}
}
else if (inc > 0){// if good ACK
checkBreak=0;
seq += inc;
if (seq==seq_expected)break;
}
//set the descriptor to check
set_fd_set(my_read_set, descriptorToCheck[1]);
select(sock_Data + 1, my_read_set, NULL, NULL, &ZERO);
}
if ( test == -1)
seq_advanced=(seq_advanced+advanced_wnd > seq+2000 || seq_advanced < seq+normal_wnd)?seq+normal_wnd:seq_advanced+advanced_wnd;
else
seq_advanced=(seq_advanced+advanced_wnd > seq + 2000 || seq_advanced+advanced_wnd> test+1)?seq+normal_wnd:seq_advanced+advanced_wnd;
} while(seq != test+1 );
printf("client dialoguing on port %d\n",ntohs(data_addr->sin_port));
for(reuse=0;reuse<1000000;reuse++)
mySendTo(sock_Data, FIN, 4, data_addr); //Send FIN to client
//to do a clean exit
myClose(sock_Data);
free(my_addr_UDP);
free(my_client_addr);
free(dataBuffer);
free_Data(DATA);
fclose(file);
printf("\e[1;3%dmEnd of connexion. Son with pid:%d is closing, communicate on %d\e[0m\n", sock_Data % 8, getpid(),port_nb);
exit(1);
}
/*======================================================================================*/
/*==================================== end of child ====================================*/
/*======================================================================================*/
}
}
