int Task2(int speed, int delay, char* filename)
{
pkg myPackage;
msg* haos;
msg t, aux;
long bdp, window;
int fdIn, count;
char infoBuffer[PKGSIZE]; /* buffer citire fisier */
int i, packNum = 0, timeout;
TLista bufferMesaje; /* buffer pachete */
int k, res;
/* setare varibaila timeout */
if(2 * delay > 1000)
timeout = 2 * delay;
else timeout = 1000;
bdp = speed * delay * 1000;
window = bdp / (FRAMESIZE * 8);
printf("[SENDER]Window = %ld frames\n", window);
printf("[SENDER]Sender starts.\n");
printf("[SENDER]Filename=%s, task_index=%d, speed=%d, delay=%d\n", filename, 2, speed, delay);
/* deschidere fisier */
fdIn = open(filename, O_RDONLY);
if(fdIn < 0) {
perror("File openning error.\n");
return -1;
}
/* pachet initializare retea */
memset(t.payload, 0, sizeof(t.payload));
memset(myPackage.payload, 0, sizeof(myPackage.payload));
myPackage.messageType = TYPE_INIT;
myPackage.packNum = window;
memcpy(myPackage.payload, filename, strlen(filename));
memcpy(t.payload, &myPackage, sizeof(pkg));
t.len = strlen(myPackage.payload) + 1;
printf("[SENDER]Sending init message.\n");
if(send_message(&t) < 0) {
fflush(stdin);
perror("Error sending init message.\n");
fflush(stdin);
return -1;
}
/* retrimit pachetul pana ce sunt sigur ca si receiverul este initializat */
while (recv_message_timeout(&aux, timeout) < 0) {
fflush(stdin);
printf("[SENDER] receive error\nWill attempt to resend.\n");
fflush(stdin);
send_message(&t);
}
printf("[SENDER] Got reply with payload: %s\n", t.payload);
/* trimitere efectiva mesaje */
window--;/* se vor trimite mesajele de la 0 la window - 1*/
printf("-----Commence filereading.-----\n");
count = read(fdIn, infoBuffer, PKGSIZE);
while(count > 0) {
/* pregatire pachet date */
memset(t.payload, 0, sizeof(t.payload));
memset(myPackage.payload, 0, sizeof(myPackage.payload));
/* actualizare tip pachet + numar de ordine */
myPackage.messageType = TYPE_INFO;
myPackage.packNum = packNum++;
if(count < PKGSIZE)
myPackage.messageType = TYPE_END;
memcpy(myPackage.payload, infoBuffer, count);
memcpy(t.payload, &myPackage, sizeof(myPackage));
printf("[SENDER]Message number %i has been sent.\n", myPackage.packNum);
t.len = count + 1;
/* creare duplicat mesaj pentru a il salva in buffer */
haos = mesageDup(&t);
send_message(&t);
InsSfL(&bufferMesaje, haos);
if(window == 0)
{
/* daca (N)ACK-ul este primit la timp */
if(recv_message_timeout(&aux, timeout) > 0)
{
/* cat timp primim NACK-uri, retrimitem pachetele in cauza */
while((*(pkg*)aux.payload).messageType == TYPE_NACK)
{
/* daca s-a primit NACK pentru un pachet care inca nu a
fost trimis */
if(k >= packNum)
break;
/* retinem numarul de ordine al pachetului pentru care
s-a primit NACK*/
k = (*(pkg*)aux.payload).packNum;
printf("[SENDER]Message %i has been resent.\n", k);
/* retrimit pachetul */
res = send_message(getPackNum(&bufferMesaje, k));
if(res < 0) {
perror("RESEND error\n");
return -1;
}
recv_message_timeout(&aux, timeout);
}
/* elimin pachetul confirmat din buffer */
printf("[SENDER]Eliminating package %i from queue.\n", (*(pkg*)aux.payload).packNum);
if(ElimPackNum(&bufferMesaje,(*(pkg*)aux.payload).packNum) < 0)
{
printf("[SENDER]Error eliminating package.\n");
return -1;
}
}
/* Daca timeout-ul a fost atins, retrimitem tot ce avem in buffer*/
else {
printf("[SENDER]Timeout reached.\n");
do {
printf("[SENDER]Attempting resend.\n");
for(i = 0; i < ListLength(&bufferMesaje); i++)
{
send_message(getindex(&bufferMesaje,i));
}
} while(recv_message_timeout(&aux, timeout) < 0);
}
}
else window--;
count = read(fdIn, infoBuffer, PKGSIZE);
}
/* s-a incheiat citirea din fisier; trimitem un pachet final */
printf("[SENDER]Filereading has ended. Last file is: %i\n", packNum);
myPackage.messageType = TYPE_END;
myPackage.packNum = packNum++;
memcpy(t.payload, &myPackage, sizeof(myPackage));
t.len = 0;
haos = mesageDup(&t);
send_message(&t);
InsSfL(&bufferMesaje, haos);
send_message(&t);
/* asteptam sa primim confirmarea tuturor pachetelor trimise */
/* NOTA: mod de operare similar cu ce avem mai sus */
printf("[SENDER]Will attempt resend for all the messages left in the buffer.\n");
while(ListLength(&bufferMesaje) >= 1)
{
/* daca (N)ACK-ul este primit la timp */
if(recv_message_timeout(&aux, timeout) > 0)
{
/* cat timp primim NACK-uri, retrimitem pachetele aferente */
while((*(pkg*)aux.payload).messageType != TYPE_ACK)
{
printf("[SENDER]Message %i has been resent.\n", k);
k = (*(pkg*)aux.payload).packNum;
if(k >= packNum)
break;
res = send_message(getPackNum(&bufferMesaje, k));
if(res < 0) {
AfisareL(&bufferMesaje);
printf("[SENDER]RESEND error.\n");
return -1;
}
recv_message_timeout(&aux, timeout);
}
/* cand am primit un ACK, eliminam pachetul respectiv din buffer*/
printf("[SENDER]Eliminating package %i from queue.\n", (*(pkg*)aux.payload).packNum);
if(ElimPackNum(&bufferMesaje,(*(pkg*)aux.payload).packNum) < 0)
{
/* eroare care nu afecteaza puternic activitatea programului,
dar trebuie semnalata */
printf("[SENDER]Error eliminating package.\n");
}
}
else {
printf("[SENDER]Timeout reached.\n");
}
/* daca a mai ramas doar mesajul de final, ne oprim */
if(ListLength(&bufferMesaje) == 1)
if( (*(pkg*)(bufferMesaje->info).payload).messageType == TYPE_END)
break;
}
printf("[SENDER]Job done.\n");
close(fdIn);
return 0;
}
int main(int argc, char *argv[])
{
char *filename;
int task_index, speed, delay, filesize;
int i, fd, timeout, res, COUNT;
int bdp, window, FRAME_SIZE;
char read_buffer[MSGSIZE];
struct stat f_status;
task_index = atoi(argv[1]);
filename = argv[2];
speed = atoi(argv[3]);
delay = atoi(argv[4]);
printf("[SENDER] Sender starts.\n");
printf("[SENDER] Filename=%s, task_index=%d, speed=%d, delay=%d\n", filename, task_index, speed, delay);
/* miliseconds for delay & megabits for speed */
bdp = speed * delay * 1000;
printf("[SENDER] BDP = %d b(bits).\n", bdp);
fd = open(filename, O_RDONLY);
fstat(fd, &f_status);
filesize = (int) f_status.st_size;
printf("[SENDER] File size: %d\n", filesize);
/* miliseconds for timeout */
if(2*delay > 1000)
timeout = 2*delay;
else
timeout = 1000;
printf("[SENDER] timeout = %d\n", timeout);
init(HOST, PORT1);
if(task_index == 0 || task_index == 1) {
msg t;
my_pkt p;
int SCAN, bsize;
queue *buffer;
buffer = (queue *) malloc(sizeof(queue));
create_queue(buffer, sizeof(msg));
FRAME_SIZE = MSGSIZE + 4;
printf("[SENDER] Each frame has %d B(bytes).\n", FRAME_SIZE);
COUNT = filesize / FRAME_SIZE;
printf("[SENDER] Gonna send %d frames.\n", COUNT);
/* window = number of frames in the 'network', unacked */
window = bdp / (FRAME_SIZE * BITS_NO);
printf("[SENDER] window = %d frames\n", window);
/* Len in message
= size(msg payload)
= amount of data in the my_pkt structure
= size(type) + data in (pkt payload)
= sizeof(int) + number of used bytes in (pkt payload)
*/
/* Gonna send filename - SEQ = -2 message */
memset(t.payload, 0, sizeof(t.payload));
memset(p.payload, 0, sizeof(p.payload));
p.SEQ = -2;
memcpy(p.payload, filename, strlen(filename));
t.len = sizeof(int) + strlen(filename) + 1;
memcpy(t.payload, &p, t.len);
while(1) {
/* send msg */
while(1) {
res = send_message(&t);
if (res < 0) {
perror("[SENDER] Send error. Resending");
continue;
}
break;
}
printf("[SENDER] Filename sent.\n");
/* Wait for filename ACK */
if (recv_message_timeout(&t, timeout) < 0) {
perror("[SENDER] Receive error: TIMEOUT. Resending");
continue;
}
p = *((my_pkt *) t.payload);
if (p.SEQ != -2) {
perror("[SENDER] Receive error: WRONG ACK. Resending");
continue;
}
printf("[SENDER] Got reply with ACK: %d (Filename)\n", p.SEQ);
break;
}
/* Gonna send filesize - SEQ = -1 message */
memset(t.payload, 0, sizeof(t.payload));
memset(p.payload, 0, sizeof(p.payload));
p.SEQ = -1;
memcpy(p.payload, &filesize, sizeof(int));
t.len = sizeof(int) * 2;
memcpy(t.payload, &p, t.len);
while(1) {
/* send msg */
while(1) {
res = send_message(&t);
if (res < 0) {
perror("[SENDER] Send error. Resending");
continue;
}
break;
}
printf("[SENDER] Filesize sent.\n");
/* Wait for filesize ACK */
if (recv_message_timeout(&t, timeout) < 0) {
perror("[SENDER] Receive error: TIMEOUT. Resending");
continue;
}
p = *((my_pkt *) t.payload);
if (p.SEQ != -1) {
perror("[SENDER] Receive error: WRONG ACK. Resending");
continue;
}
printf("[SENDER] Got reply with ACK: %d (Filesize)\n", p.SEQ);
break;
}
/* Send file contents - (SEQ = 0 -> COUNT) messages */
int seq = 0;
/* Fill the link = send window messages */
for (i = 0; i < window; i++) {
if((SCAN = read(fd, read_buffer, MSGSIZE - sizeof(int))) > 0) {
memset(t.payload, 0, sizeof(t.payload));
memset(p.payload, 0, sizeof(p.payload));
p.SEQ = seq;
memcpy(p.payload, read_buffer, SCAN);
t.len = sizeof(int) + SCAN;
memcpy(t.payload, &p, t.len);
printf("[SENDER] Sending message with SEQ: %d\n", seq);
/* put msg in buffer */
enqueue(buffer, &t);
/* send msg */
while(1) {
res = send_message(&t);
if (res < 0) {
perror("[SENDER] Send error. Resending");
continue;
}
break;
}
seq++;
}
else
break;
}
/* From now on, ack clocking, i.e., a new ack will inform
us about the space released in the link */
while(1) {
/* wait for ACK */
if (recv_message_timeout(&t, timeout) < 0) {
perror("[SENDER] Receive error: TIMEOUT. Resending buffer");
bsize = buffer->size;
while(bsize) {
/* clear msg from buffer */
dequeue(buffer, &t);
/* send msg */
while(1) {
res = send_message(&t);
if (res < 0) {
perror("[SENDER] Send error. Resending");
continue;
}
break;
}
/* reput msg in buffer, in case it will be lost again */
enqueue(buffer, &t);
bsize--;
}
continue;
}
else {
p = *((my_pkt *) t.payload);
printf("[SENDER] Got reply with ACK: %d\n", p.SEQ);
/* clear succesfully sent msg from buffer */
dequeue(buffer, &t);
if((SCAN = read(fd, read_buffer, MSGSIZE - sizeof(int))) > 0) {
memset(t.payload, 0, sizeof(t.payload));
memset(p.payload, 0, sizeof(p.payload));
p.SEQ = seq;
memcpy(p.payload, read_buffer, SCAN);
t.len = sizeof(int) + SCAN;
memcpy(t.payload, &p, t.len);
printf("[SENDER] Sending message with SEQ: %d\n", seq);
/* put msg in buffer */
enqueue(buffer, &t);
/* send msg */
while(1) {
res = send_message(&t);
if (res < 0) {
perror("[SENDER] Send error. Resending");
continue;
}
break;
}
seq++;
}
else
if(buffer->size == 0)
break;
}
}
destroy_queue(buffer);
free(buffer);
}
printf("[SERVER] File transfer has ended.\n");
close(fd);
return 0;
}
