bool DUChainLock::lockForRead(unsigned int timeout)
{
///Step 1: Increase the own reader-recursion. This will make sure no further write-locks will succeed
d->changeOwnReaderRecursion(1);
if(d->m_writer == 0 || d->m_writer == QThread::currentThreadId())
{
//Successful lock: Either there is no writer, or we hold the write-lock by ourselves
}else{
///Step 2: Start spinning until there is no writer any more
timeval startTime;
gettimeofday(&startTime, 0);
while(d->m_writer)
{
timeval currentTime;
gettimeofday(¤tTime, 0);
timeval waited;
timersub(¤tTime, &startTime, &waited);
if(!timeout || toMilliSeconds(waited) < timeout) {
usleep(uSleepTime);
} else {
//Fail!
d->changeOwnReaderRecursion(-1);
return false;
}
}
}
return true;
}
bool DUChainLock::lockForWrite(uint timeout)
{
//It is not allowed to acquire a write-lock while holding read-lock
Q_ASSERT(d->ownReaderRecursion() == 0);
if(d->m_writer == QThread::currentThreadId())
{
//We already hold the write lock, just increase the recursion count and return
d->m_writerRecursion.fetchAndAddRelaxed(1);
return true;
}
timeval startTime;
gettimeofday(&startTime, 0);
while(1)
{
//Try acquiring the write-lcok
if(d->m_totalReaderRecursion == 0 && d->m_writerRecursion.testAndSetOrdered(0, 1))
{
//Now we can be sure that there is no other writer, as we have increased m_writerRecursion from 0 to 1
d->m_writer = QThread::currentThreadId();
if(d->m_totalReaderRecursion == 0)
{
//There is still no readers, we have successfully acquired a write-lock
return true;
}else{
//There may be readers.. we have to continue spinning
d->m_writer = 0;
d->m_writerRecursion = 0;
}
}
timeval currentTime;
gettimeofday(¤tTime, 0);
timeval waited;
timersub(¤tTime, &startTime, &waited);
if(!timeout || toMilliSeconds(waited) < timeout) {
usleep(uSleepTime);
} else {
//Fail!
return false;
}
}
return false;
}
QString DateTime::toString(const QString &rFormat) const
{
QString format(rFormat);
if (format.isEmpty())
return QString();
if (!isValid())
return QString();
if (format == QLatin1String("NONE"))
return QString();
if (format == QLatin1String("RELATIVE"))
return QString::number(toMilliSeconds() - InitialisationHelper::startTime());
if (format == QLatin1String("ISO8601"))
format = QLatin1String("yyyy-MM-dd hh:mm:ss.zzz");
if (format == QLatin1String("ABSOLUTE"))
format = QLatin1String("HH:mm:ss.zzz");
if (format == QLatin1String("DATE"))
format = QLatin1String("dd MMM YYYY HH:mm:ss.zzzz");
return formatDateTime(format);
}
int main(int argc, char *argv[])
{
/* Packet Thread */
/* Initialize the mutex */
pthread_mutex_init(&m, 0);
int i;
char *lambda = "0.5";
char *mu = "0.35";
char *r = "1.5";
char *B = "10";
char *P = "3";
char *n = "20";
char *FILENAME = NULL;
AVAILABLE = 0;
DROPPED = 0;
DROPPED_PKT = 0;
TOTAL = 0;
TOTAL_SERVED = 0;
SERVER_DIE = 0;
/* Read Options */
for(i=1;i<argc;i=i+2){
if (i%2!=0 && argv[i][0]=='-'){
if ((strcmp(argv[i]+1, "lambda") == 0) && ((i+1)<argc)){
lambda = argv[i+1];
if(check_num(lambda)== -1){
fprintf(stderr, "Value of lambda is not a number.\n");
exit(0);
}
continue;
}
else if ((strcmp(argv[i]+1, "mu") == 0) && ((i+1)<argc)){
mu = argv[i+1];
if(check_num(mu)== -1){
fprintf(stderr, "Value of mu is not a number.\n");
exit(0);
}
continue;
}
else if ((strcmp(argv[i]+1, "r") == 0) && ((i+1)<argc)){
r = argv[i+1];
if(check_num(r)== -1){
fprintf(stderr, "Value of r is not a number.\n");
exit(0);
}
continue;
}
else if ((strcmp(argv[i]+1, "B") == 0) && ((i+1)<argc)){
B = argv[i+1];
if(isNum(B)==-1){
fprintf(stderr, "Value of B is not a number.\n");
exit(0);
}
continue;
}
else if((strcmp(argv[i]+1, "P") == 0) && ((i+1)<argc)){
P = argv[i+1];
if(isNum(P) == -1){
fprintf(stderr, "Value of P is not a number.\n");
exit(0);
}
continue;
}
else if ((strcmp(argv[i]+1, "n") == 0) && ((i+1)<argc)){
n = argv[i+1];
if(isNum(n)==-1){
fprintf(stderr, "Value of n is not a number.\n");
exit(0);
}
continue;
}
else if ((strcmp(argv[i]+1, "t") == 0) && ((i+1)<argc)){
FILENAME = argv[i+1];
continue;
}
}
fprintf(stderr, "Wrong command line argument\n");
exit(0);
break;
}
/*Allocate memory to list*/
Q1 = malloc(sizeof(My402List));
Q2 = malloc(sizeof(My402List));
/*Initilialize the list*/
My402ListInit(Q1);
My402ListInit(Q2);
/* Block Signal from Main thread */
block_signal();
if(FILENAME!=NULL){
FILE *fp = fopen(FILENAME, "r");
if(fp==NULL){
perror("Error: Unable to open the file ");
exit(0);
}
fclose(fp);
}
print_input(lambda, mu, FILENAME, r, B, P, n);
/* Create packet thread */
fprintf(stdout, "\n");
/* Initialize the stats */
init_stats();
struct timeval current = diff_timeval(START_TIMEVAL, PKT_BEFORE);
fprintf(stdout, "%08llu.%03ldms: emulation begins\n",
toMilliSeconds(current), current.tv_usec%MILLI);
/* Create threads */
create_packet_thread(lambda, mu, FILENAME, r, B, P, n);
/* Print statistics */
//print_stats();
return(0);
}
