feat: Initial commit

Lab08/ex1.c

@@ -0,0 +1,28 @@
+
+int ticketNumber;
+int turnNumber;
+
+int atomicIncrement (int *var) {
+  int tmp = *var;
+  *var = tmp + 1;
+  return (tmp);
+}
+
+void init() {
+	ticketNumber = 0;
+	turnNumber = 0;
+}
+
+void lock() {
+	int ticket = atomicIncrement(&ticketNumber);
+
+	while (ticket != turnNumber);
+
+void unlock() {
+	atomicIncrement(turnNumber);
+}
+
+int main() {
+
+
+}

Lab08/ex2.c

@@ -0,0 +1,80 @@
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdio.h>
+
+typedef int * sem;
+
+sem sem_init() {
+	sem s = calloc(2, sizeof(int));
+	pipe(s);
+	return s;
+}
+
+void sem_lock(sem s) {
+	int tmp;
+	if (read(s[0], &tmp, 1)<0) exit(1);
+}
+
+void sem_multi_lock(sem s, int n) {
+	for (int i = 0; i < n; i++) sem_lock(s);
+}
+
+void sem_signal(sem s) {
+	if (write(s[1], "0", 1)<0) exit(1);
+}
+
+void A(sem sB, sem sC, sem sD) {
+	puts("A");
+	sem_signal(sB);
+	sem_signal(sC);
+	sem_signal(sD);
+}
+
+void single_proc(sem x, sem y, int N, char * name) {
+	sem_multi_lock(x, N);
+	puts(name);
+	sem_signal(y);
+}
+
+void C(sem sC, sem sE, sem sF) {
+	sem_lock(sC);
+	puts("C");
+	sem_signal(sE);
+	sem_signal(sF);
+}
+
+int main() {
+	sem sA, sB, sC, sD, sE, sF, sG, sH, sI;
+	sA = sem_init();
+	sB = sem_init();
+	sC = sem_init();
+	sD = sem_init();
+	sE = sem_init();
+	sF = sem_init();
+	sG = sem_init();
+	sH = sem_init();
+	sI = sem_init();
+	while(1) {
+		if (!fork()) {
+			A(sB,sC,sD);
+		} else if (!fork()) {
+			single_proc(sB, sI, 1, "B");	
+		} else if (!fork()) {
+			C(sC, sE, sF);
+		} else if (!fork()) {
+			single_proc(sD, sH, 1, "D");	
+		} else if (!fork()) {
+			single_proc(sE, sG, 1, "E");	
+		} else if (!fork()) {
+			single_proc(sF, sG, 1, "F");	
+		} else if (!fork()) {
+			single_proc(sG, sI, 2, "G");	
+		} else if (!fork()) {
+			single_proc(sH, sI, 1, "H");	
+		} else if (!fork()) {
+			single_proc(sI, sA, 3, "I");	
+		}
+		sem_lock(sA);
+		sleep(5);
+	}
+}

Lab08/ex4.c

@@ -0,0 +1,57 @@
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <pthread.h>
+#include <semaphore.h>
+
+sem_t *sems[6];
+
+typedef struct params {
+	int sPrev; 
+	int sNext;
+	int nPrev;
+	int nNext;
+	char * name;
+} *params_t;
+
+void* t_code(void * arg) {
+	params_t p = (params_t) arg;
+	while (1) {
+		for (int i = 0; i < p->nPrev; i++) sem_wait(sems[p->sPrev]);
+		puts(p->name);
+		sleep(3);
+		for (int i = 0; i < p->nNext; i++) sem_post(sems[p->sNext]);
+	}
+	free(p);
+}
+
+pthread_t* start_t(int sPrev, int sNext, int nPrev, int nNext, char * name) {
+	pthread_t *t;
+	params_t p = malloc(sizeof(struct params));
+	p->sPrev = sPrev;
+	p->sNext = sNext;
+	p->nPrev = nPrev;
+	p->nNext = nNext;
+	p->name = name;
+	pthread_create(t, NULL, t_code, (void *) p);
+	return t;
+}
+
+int main() {
+	for (int i = 0; i < 6; i++) {
+		sems[i] = malloc(sizeof(sem_t)); 
+		sem_init(sems[i], 0, 0);
+	}
+	sem_post(sems[0]);
+	start_t(0, 1, 1, 3, "A");
+	start_t(1, 2, 1, 1, "B");
+	start_t(1, 3, 1, 2, "C");
+	start_t(1, 4, 1, 1, "D");
+	start_t(3, 5, 1, 1, "E");
+	start_t(3, 5, 1, 1, "F");
+	start_t(5, 2, 1, 1, "G");
+	start_t(4, 2, 1, 1, "H");
+	start_t(2, 0, 3, 1, "I");
+
+	sleep(24);
+}