/*
* The program is passed as a vector of strings which is parsed from the text file back in main.
* I do this in part due to the single responsibility principle. However, the main reason is that
* it allows me to easily write unit test which exercise the functionality of the CPU.
* The unit test are likely not include with this assignment.
*/
ComputerSim::ComputerSim(const std::vector<std::string>& program, const int timerInterval) {
int cpuToMem[2];
int memToCpu[2];
tryPipe(cpuToMem, memToCpu);
int forkResult = tryFork();
if (isChild(forkResult)) {
Memory m(cpuToMem[0], memToCpu[1], program);
} else if (isParent(forkResult)) {
Cpu c(memToCpu[0], cpuToMem[1], timerInterval);
waitpid(-1, NULL, 0); // wait for child
}
}
static void forkSort(int* parentNums, int size, int write_fd)
{
int fd[2];
printf("PPid:%ld Pid:%ld Size:%d\n", (long)getppid(), (long)getpid(), size);
int childNums[size/2], left, right;
if(size <= 100) //Send sorted array to parent thru pipe
{
qsort(parentNums, size, sizeof(int), compare);
write(write_fd, parentNums, size*sizeof(int));
exit(0);
}
if (pipe(fd)==-1){perror("Failed");}
printf("Creating child processes...\n");
size /= 2;
if(!(left = tryFork()) || !(right = tryFork())) //Children
{
if(left) copy(childNums, parentNums, size);
else copy(childNums, parentNums + size, size);
forkSort(childNums, size, fd[1]);
}
/* parent */
int first[size], second[size], combined[size*2];
read(fd[0], first, sizeof(first));
read(fd[0], second, sizeof(second));
printf("\n\nMerge sorting... Size:%d\n", size*2);
mergeSort(first, second, combined, size);
if(size*2 == SIZE) { //Finished, write to out.dat
printf("\nFinished!!! (%d)\n\n", size * 2);
printArray(combined, SIZE);
}
else {
write(write_fd, combined, sizeof(combined));
exit(0);
}
}