Program with 5 philosophers typically works. Currently unable to find cause of variation.

DiningPhilosophers.c

@@ -53,7 +53,7 @@ int main(int argc, char* argv[])
 bool AllPhilosophersFull(PhilosopherData PhilosopherList[], int numPhilosophers)
 {
     for (int i = 0; i < numPhilosophers; i++)
-        if (PhilosopherList[i].eatingCount < 1)
+        if (PhilosopherList[i].eatingCount < 2)
             return false;
     return true;
 }
@@ -69,6 +69,7 @@ void PhilosopherWait()
 void Eat(PhilosopherData* philosopherSelected)
 {
     printf("Philosopher %d is eating...\n", philosopherSelected->position);
+    philosopherSelected->state = EATING;
     ++philosopherSelected->eatingCount;
 }
 
@@ -87,6 +88,11 @@ void* Philosopher(void* philosopherPassed)
     while (true)
     {
         Think(philosopherSelected);                /*philosopher is thinking*/
+        if (philosopherSelected->eatingCount == 2)
+        {
+            printf("Philosopher %d ate twice...\n", philosopherSelected->position);
+            return;
+        }
         TakeForks(philosopherSelected);          /*acquire two forks or block*/
         Eat(philosopherSelected);                  /*yum-yum, spaghetti*/
         PutForks(philosopherSelected);           /*put both forks back on table*/
@@ -101,16 +107,16 @@ void PhilosopherInit(int philosopherTotal)
     sem_init(&semaphore, 0, 1);
     while (!AllPhilosophersFull(PhilosopherList, philosopherTotal))
     {
-        sleep(2);
         for (int i = 0; i < philosopherTotal; i++)
         {
-            if (PhilosopherCanEat(PhilosopherList, i, philosopherTotal))
-            {
-                printf("Philosopher %d was allowed to eat...\n", i);
-                PhilosopherList[i].state = EATING;
-                AllowPhilosopher();
-            }
+            printf("Philosopher %d state: %d\n", PhilosopherList[i].position, PhilosopherList[i].state);
         }
+        AllowPhilosopher();
+        sleep(1);
+    }
+    for (int i = 0; i < philosopherTotal; i++)
+    {
+        printf("Philosopher %d eating count: %d\n", PhilosopherList[i].position, PhilosopherList[i].eatingCount);
     }
 }
 
@@ -121,7 +127,9 @@ void PhilosopherListInit(PhilosopherData PhilosopherList[], int philosopherTotal
     {
         PhilosopherList[i].position = i;
         PhilosopherList[i].eatingCount = 0;
+        PhilosopherList[i].state = THINKING;
         pthread_create(&PhilosopherList[i].thread, NULL, &Philosopher, &PhilosopherList[i]);
+        // pthread_join(&PhilosopherList[i].thread, NULL);
     }
 }
 
@@ -146,12 +154,15 @@ bool PhilosopherCanEat(PhilosopherData PhilosopherList[], int selectedPosition,
 {
     if (PhilosopherList[selectedPosition].state != HUNGRY)
         return false;
-    int leftPhilosopher = (selectedPosition + (philosopherTotal-1)) % philosopherTotal;
-    int rightPhilosopher = (selectedPosition + 1) % philosopherTotal;
-    if (PhilosopherList[leftPhilosopher].state == EATING)
-        return false;
-    if (PhilosopherList[rightPhilosopher].state == EATING)
-        return false;
+    // int leftPhilosopher = (selectedPosition + (philosopherTotal-1)) % philosopherTotal;
+    // int rightPhilosopher = (selectedPosition + 1) % philosopherTotal;
+    // if (PhilosopherList[leftPhilosopher].state == EATING)
+    //     return false;
+    // if (PhilosopherList[rightPhilosopher].state == EATING)
+    //     return false;
+    for (int i = 0; i < philosopherTotal; i++)
+        if (PhilosopherList[i].state == EATING)
+            return false;
     return true;
 }
 

TestDining.sh

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