Massive backlog of changes

include/priorityqueue.h

@@ -1,11 +1,31 @@
 #pragma once
 
-#include "pageallocator.h"
-#include "kernel.h"
-#include <stddef.h>
+/**
+ * @brief An pair consisting of a priority and a pointer to be stored in 
+ * a priority queue.
+ * 
+ */
+struct priority_queue_node_t
+{
+    /**
+     * @brief A pointer to some user-defined object.
+     * 
+     */
+    void *value;
+
+    /**
+     * @brief The priority of the associated object. Only the object with the
+     * lowest priority is directly accessible from a priority queue.
+     * 
+     */
+    int priority;
+};
 
 /**
- * @brief 
+ * @brief A priority queue. Each object in the queue contains a priority and
+ * a pointer to some user-defined value, and a priority. Operations on the
+ * queue consist of insertion and deletion of objects, and extraction of the
+ * object with the lowest priority.
  * 
  */
 struct priority_queue_t
@@ -14,45 +34,59 @@ struct priority_queue_t
      * @brief A pointer to the heap described by this structure.
      * 
      */
-    struct process_t **heap;
+    struct priority_queue_node_t *heap;
 
     /**
      * @brief The current number of elements stored in the heap.
      * 
      */
-    size_t size;
+    int size;
 
     /**
      * @brief The maximum number of elements that the heap can currently hold.
      * 
      */
-    size_t capacity;
+    int capacity;
 };
 
-int construct_priority_queue(struct priority_queue_t *queue, struct page_stack_t *page_stack);
-
 /**
- * @brief 
+ * @brief Initializes the given queue struct.
+ * 
+ * The queue's underlying heap is allocated
  * 
  * @param queue 
- * @return struct process_t* 
- */
-struct process_t *extract_min(struct priority_queue_t *queue);
-
-/**
- * @brief 
- * 
- * @param queue 
- * @param process 
  * @return int 
  */
-int queue_insert(struct priority_queue_t *queue, struct process_t *process);
+int construct_priority_queue(struct priority_queue_t *queue, int capacity);
 
 /**
- * @brief 
+ * @brief Extracts the object with the lowest priority off the given queue.
+ * 
+ * The object is removed from the queue, and a pointer to its userdata is
+ * returned. If the queue is empty, this function returns NULL and the queue
+ * is unaffected. If multiple objects with the same priority are stored on the
+ * queue, this function will extract the object lest-recently inserted.
  * 
  * @param queue 
- * @param process 
+ * @return void* 
+ */
+void *extract_min(struct priority_queue_t *queue);
+
+/**
+ * @brief Inserts a new object onto the queue.
+ * 
+ * @param queue 
+ * @param value 
+ * @param priority
  * @return int 
  */
-int queue_remove(struct priority_queue_t *queue, struct process_t *process);
+int queue_insert(struct priority_queue_t *queue, void *value, int priority);
+
+/**
+ * @brief Removes the object with a matching value from the queue.
+ * 
+ * @param queue 
+ * @param value 
+ * @return int 
+ */
+int queue_remove(struct priority_queue_t *queue, void *value);