int main(void)
{
char user[10], pass[10];
int logres, seats, bookres, bookch, loginch, usercheck;
int maxseats = 20; //hardcoded max seats available
system("cls");
printf("\nWelcome to Railway booking system!\n");
//Provide option to login or sign up
printf("1. Press 1 to Login if you have already signed up.\n");
printf("2. Press 2 to Sign Up.\n\n");
printf("Your Choice?: ");
scanf("%d", &loginch);
usercheck = logincheck(loginch); //Check if user opted for login or sign-up
if(usercheck == 1) //user opted for login in loginch, logincheck() returns 1
{
A: //label to return to login after sign-up
printf("\nUser Login:\nPlease enter your username and password:\n");
printf("Username: "******"%s", user);
printf("Password: "******"%s", pass);
logres = login(user, pass); //call to login, checks if user name and pass are correct
if(logres == 1) //login success if login returns 1 above, ie. user name and pass are correct
{
printf("Login successful!\n\nPlease proceed for booking!\n20 Seats available!");
printf("\nPlease enter number of seats: ");
scanf("%d", &seats);
bookres = booking(seats, maxseats); //allow booking only if login success,
//call booking() with no of seats user enters and max seats
if(bookres == 1)//booking() above checks if enough seats are available, returns 1 if available
{
printf("\nEnough seats available! Proceed for booking.\n\n");
//Allow class selection if seats available
printf("Please select your class:\n");
printf("1.Enter 1 for AC 1 Tier.\n");
printf("2.Enter 2 for AC 2 Tier.\n");
printf("3.Enter 3 for AC 3 Tier.\n");
printf("4.Enter 4 for Sleeper.\n");
printf("\nYour choice?: ");
scanf("%d", &bookch);
maxseats = bookmenu(bookch, seats, maxseats); //Actual Booking, call to bookmenu()
}
else //booking returns 0 if user entered seats exceeds available seats
{
printf("Not enough seats!");
}
}
else //login returns 0 if username OR pass is incorrect, comparison fails
{
printf("Invalid username or password!");
}
}
else if(usercheck == 2)//user opted for sign-up, logincheck() returns 2
{
createuser();//Call user creation module
system("cls");
goto A; //continue with login, after user creation
}
printf("\n\nThank You for using the Railway booking system. Press any key to exit!");
getche();
return 0;
}
static int
mklock(char *file)
{
int fd, try;
Dir *dir;
fd = openlock(file);
if (fd >= 0) {
/* make it a lock file if it wasn't */
dir = dirfstat(fd);
if (dir == nil)
error("%s vanished: %r", file);
dir->mode |= DMEXCL;
dir->qid.type |= QTEXCL;
dirfwstat(fd, dir);
free(dir);
/* reopen in case it wasn't a lock file at last open */
close(fd);
}
for (try = 0; try < 65 && (fd = openlock(file)) < 0; try++)
sleep(10*1000);
return fd;
}
void
main(int argc, char *argv[])
{
Job *j;
Tm tm;
Time t;
ulong now, last; /* in seconds */
int i, lock;
debug = 0;
ARGBEGIN{
case 'c':
createuser();
exits(0);
case 'd':
debug = 1;
break;
default:
usage();
}ARGEND
if(debug){
readalljobs();
printjobs();
exits(0);
}
initcap(); /* do this early, before cpurc removes it */
switch(fork()){
case -1:
fatal("can't fork: %r");
case 0:
break;
default:
exits(0);
}
/*
* it can take a few minutes before the file server notices that
* we've rebooted and gives up the lock.
*/
lock = mklock("/cron/lock");
if (lock < 0)
fatal("cron already running: %r");
argv0 = "cron";
srand(getpid()*time(0));
last = time(0);
for(;;){
readalljobs();
/*
* the system's notion of time may have jumped forward or
* backward an arbitrary amount since the last call to time().
*/
now = time(0);
/*
* if time has jumped backward, just note it and adapt.
* if time has jumped forward more than a day,
* just execute one day's jobs.
*/
if (now < last) {
clog("time went backward");
last = now;
} else if (now - last > Day) {
clog("time advanced more than a day");
last = now - Day;
}
now = minute(now);
for(last = minute(last); last <= now; last += Minute){
tm = *localtime(last);
t.min = 1ULL << tm.min;
t.hour = 1 << tm.hour;
t.wday = 1 << tm.wday;
t.mday = 1 << tm.mday;
t.mon = 1 << (tm.mon + 1);
for(i = 0; i < nuser; i++)
for(j = users[i].jobs; j; j = j->next)
if(j->time.min & t.min
&& j->time.hour & t.hour
&& j->time.wday & t.wday
&& j->time.mday & t.mday
&& j->time.mon & t.mon)
rexec(&users[i], j);
}
seek(lock, 0, 0);
write(lock, "x", 1); /* keep the lock alive */
/*
* if we're not at next minute yet, sleep until a second past
* (to allow for sleep intervals being approximate),
* which synchronises with minute roll-over as a side-effect.
*/
sleepuntil(now + Minute + 1);
}
/* not reached */
}
