2019-11-08 in class

midterm/processes/processes.c

@@ -11,7 +11,8 @@ struct process {
 	uint pid;
 	uint ppid;
 	char user[9];
-	float priority;
+	uint priority;
+	float cpu;
 	ulong resident_size;
 	ulong size;
 	ulong virtual_size;
@@ -24,6 +25,12 @@ struct processes {
 	struct process* procs;
 };
 
+struct query_result {
+	ulong size;
+	ulong i;
+	struct process** procs;
+};
+
 struct processes* new_processes() {
 	struct processes* p = malloc(sizeof(struct processes));
 	if (!p) {
@@ -54,8 +61,8 @@ int add_from_file(struct processes* ps, const char* filename) {
 	}
 
 	struct process p;
-	while (fscanf(f, "%u %u %8s %f %lu %lu %lu %15s\n", &p.pid, &p.ppid,
-			p.user, &p.priority,&p.resident_size, &p.size,
+	while (fscanf(f, "%u %u %8s %u %f %lu %lu %lu %15s\n", &p.pid, &p.ppid,
+			p.user, &p.priority, &p.cpu, &p.resident_size, &p.size,
 			&p.virtual_size, p.command) == 8) {
 
 		if (ps->size == ps->capacity) {
@@ -71,6 +78,82 @@ int add_from_file(struct processes* ps, const char* filename) {
 		ps->procs[ps->size] = p;
 		ps->size++;
 	}
+
+	fclose(f);
+	return 1;
 }
 
+void clear(struct processes* p) {
+	p->size = 0;
+	// may shrink p->procs here
+}
 
+struct query_result* search(struct processes* ps, const struct query* q) {
+	ulong capacity = INIT_CAP;
+	struct query_result* res = malloc(sizeof(struct query_result));
+	if (!res) {
+		return NULL;
+	}
+
+	res->size = 0;
+	res->i = 0;
+	res->procs = malloc(sizeof(struct process*) * capacity);
+	if (!res->procs) {
+		free(res);
+		return NULL;
+	}
+
+	for (ulong i = 0; i < ps->size; i++) {
+		int add;
+
+		struct process* p = &(ps->procs[i]);
+
+		add = (q->priority == 0 || (q->priority < 0 &&
+			(uint)(q->priority * -1) < p->priority) ||
+			(q->priority > 0 && (uint) q->priority == p->priority));
+		add = add && (q->rss == 0 || (q->rss < 0 &&
+			(ulong)(q->rss * -1) < p->resident_size) ||
+			(q->rss > 0 && (ulong) q->rss == p->resident_size));
+		add = (q->size == 0 || (q->size < 0 &&
+			(ulong)(q->size * -1) < p->size) ||
+			(q->size > 0 && (ulong) q->size == p->size));
+		add = (q->vsize == 0 || (q->vsize < 0 &&
+			(ulong)(q->vsize * -1) < p->virtual_size) ||
+			(q->vsize > 0 && (ulong) q->vsize == p->virtual_size));
+		add = (q->cpu_usage == 0 || (q->cpu_usage < 0 &&
+			q->cpu_usage * -1 < p->cpu) ||
+			(q->cpu_usage > 0 && q->cpu_usage == p->cpu));
+
+		if (add) {
+			res->procs[res->size] = p;
+			res->size++;
+			if (res->size == capacity) {
+				capacity *= 2;
+				struct process** new_procs = realloc(res->procs,
+					sizeof(struct process*) * capacity);
+				if (!new_procs) {
+					free(res->procs);
+					free(res);
+					return NULL;
+				}
+				res->procs = new_procs;
+			}
+		}
+	}
+
+	return res;
+}
+
+struct query_result* next(struct query_result* q) {
+	if (q->i == q->size) {
+		terminate_query(q);
+		return NULL;
+	}
+	q->i++;
+	return q;
+}
+
+void terminate_query(struct query_result* q) {
+	free(q->procs);
+	free(q);
+}