Removed useless comments and old code

DiningPhilosophers.c

@@ -5,9 +5,6 @@
 #include <stdio.h>
 #include <unistd.h>
 
-// #define N           5           /*number of philosophers*/
-// #define LEFT        (i+N-1)%N   /*number of i's left neighbor*/
-// #define RIGHT       (i+1)%N     /*number of i's right neighbor*/
 #define THINKING    0           /*philosopher is thinking*/
 #define HUNGRY      1           /*philosopher is trying to get forks*/
 #define EATING      2           /*philosopher is eating*/
@@ -23,7 +20,7 @@ typedef struct PhilosopherData {
 } PhilosopherData;
 
 bool AllPhilosophersFull(PhilosopherData PhilosopherList[], int numPhilosophers);
-void Down();
+void Down(sem_t* semaphore);
 void Eat(PhilosopherData* philosopherSelected);
 int GetPhilosopherCount(char* argv);
 void* Philosopher(void* philosopherPassed);
@@ -33,18 +30,16 @@ void PutForks(PhilosopherData* philosopherSelected);
 void TakeForks(PhilosopherData* philosopherSelected);
 bool PhilosopherCanEat(PhilosopherData PhilosopherList[], int selectedPosition, int philosopherTotal);
 void Think(PhilosopherData* philosopherSelected);
-void Up();
+void Up(sem_t* semaphore);
 
 /*
  *  Todo:
- *      Add prints to each state change
  *      Fix each function's requirements
  *  Theories:
  *      Threads should be put to sleep if can't eat
  *      Sleep has to be awoken by something else, process can't wake own thread
  *      Place semaphores so states can be checked by all
  *      Total fork count = N / 2
- *
  */
 
 int main(int argc, char* argv[]) 
@@ -73,21 +68,18 @@ bool AllPhilosophersFull(PhilosopherData PhilosopherList[], int numPhilosophers)
     return true;
 }
 
-//
+//  Takes a pointer to a philosopher and puts semaphore into waiting state.
 //  TODO:
 //      Turn function into picking up forks (starting waits)
 //      (Right fork is owned by selectedPhilosopher number for consistency)
 //      Add sem_wait
-void Down()
+void Down(sem_t* semaphore)
 {
-    printf("Down() was called...\n");
+    sem_wait(semaphore);
+    printf("A semaphore was put into waiting...\n");
 }
 
-// 
-//  TODO: 
-//      Add changing state to function
-//      Add increasing eating count functionality
-//
+// Sets philosopher to eating state and increments eating count.
 void Eat(PhilosopherData* philosopherSelected)
 {
     printf("Philosopher %d is eating...\n", philosopherSelected->position);
@@ -95,8 +87,7 @@ void Eat(PhilosopherData* philosopherSelected)
     ++philosopherSelected->eatingCount;
 }
 
-// Takes in char* and converts into a number
-// Returns a number
+// Converts char* to number.
 int GetPhilosopherCount(char* argv)
 {
     int philosopherTotal;
@@ -104,18 +95,10 @@ int GetPhilosopherCount(char* argv)
     return philosopherTotal;
 }
 
-// Takes in the number of philosophers, from 0 to N-1
-// Finishes when all philosophers have eaten twice
-// TODO:
-//      Add splitting function into multiple pthreads
+//  Main function that each thread runs.
 void* Philosopher(void* philosopherPassed)
 {
     PhilosopherData *philosopherSelected = (PhilosopherData*) philosopherPassed;
-    // Below replaced by PhilosopherData
-    // int philosopherEatingCount[numPhilosophers];
-    // sem_t philosopherSemaphore[numPhilosophers];                 /*one semaphore per philospher*/
-    // // array to keep track of everyone's state
-    // int philosopherState[numPhilosophers];
     while (true)
     {
         Think(philosopherSelected);                /*philosopher is thinking*/
@@ -126,6 +109,7 @@ void* Philosopher(void* philosopherPassed)
     }
 }
 
+//  Handles all philosopher threads, finishes when all philosophers are full.
 void PhilosopherInit(int philosopherTotal)
 {
     PhilosopherData PhilosopherList[philosopherTotal];
@@ -136,11 +120,10 @@ void PhilosopherInit(int philosopherTotal)
         {
             if (PhilosopherCanEat(PhilosopherList, i, philosopherTotal))
             {
-                Down(PhilosopherList[i-1].semaphore);
-                Down(PhilosopherList[i].semaphore);
+                Up(&(PhilosopherList[i-1].semaphore));
+                Up(&(PhilosopherList[i].semaphore));
             }
         }
-        break;
     }
 }
 
@@ -167,11 +150,11 @@ void PutForks(PhilosopherData* philosopherSelected)
     // Up(&mutex);                 /*block if forks were not acquired*/
 }
 
-// Takes in a number for a selected philosopher, from 0 to N-1
+//  Philosopher takes the forks on the left and right.
 void TakeForks(PhilosopherData* philosopherSelected)
 {
     printf("Philosopher %d is taking forks...\n", philosopherSelected->position);
-    sem_wait(&philosopherSelected->semaphore);
+    Down(&philosopherSelected->semaphore);
     // Down(&mutex);               /*enter critical region*/
     // PhilosopherList.state = HUNGRY;          /*philosopher has finished eating*/
     // Test(selectedPhilosopher, );                    /*see if left neighbor can now eat*/
@@ -179,9 +162,9 @@ void TakeForks(PhilosopherData* philosopherSelected)
     // Down(&philosopherSemaphore[selectedPhilosopher]);                /*exit critical region*/
 }
 
-// Takes in the number of philosophers, from 0 to N-1
-// Checks if left and right philosopher is not eating,
-//      and philosopher is hungry, then philosopher will eat
+//  If philosopher is hungry and forks are free, then returns true.
+//  Else, philosopher returns false.
+//  Left philosopher math: (i+N-1)%N    Right philosopher math: (i+1)%N
 bool PhilosopherCanEat(PhilosopherData PhilosopherList[], int selectedPosition, int philosopherTotal)
 {
     if (PhilosopherList[selectedPosition].state != HUNGRY)
@@ -206,7 +189,8 @@ void Think(PhilosopherData* philosopherSelected)
 // Todo:
 //      Make function release hold on semaphore
 //      Use 'sem_post'
-void Up()
+void Up(sem_t* semaphore)
 {
-    printf("Up() was called...\n");
+    sem_post(semaphore);
+    printf("A semaphore was released...\n");
 }

TestDining.sh

@@ -1,4 +1,4 @@
 #!/bin/bash
 rm DiningPhilosophers.out
 gcc DiningPhilosophers.c -o DiningPhilosophers.out 2> crashCompile.log
-./DiningPhilosophers.out 5 > output.log 2> crashLaunch.log
+./DiningPhilosophers.out 5