Added queue structure

include/kernel.h

@@ -85,6 +85,14 @@ int store_active_context(struct process_context_t *context, size_t size);
 
 struct process_context_t *get_active_context();
 
+int open_port(int id);
+
+int close_port(int id);
+
 int send_message(int recipient, struct message_t *message);
 
+int receive_message(struct message_t *buffer);
+
+int request_message(struct message_t *buffer, void *temp);
+
 void panic(const char *message) __attribute__ ((noreturn));

include/priorityqueue.h

@@ -70,7 +70,7 @@ int construct_priority_queue(struct priority_queue_t *queue, int capacity);
  * @param queue 
  * @return void* 
  */
-void *extract_min(struct priority_queue_t *queue);
+void *priorityqueue_extract_min(struct priority_queue_t *queue);
 
 /**
  * @brief Inserts a new object onto the queue.
@@ -80,7 +80,7 @@ void *extract_min(struct priority_queue_t *queue);
  * @param priority
  * @return int 
  */
-int queue_insert(struct priority_queue_t *queue, void *value, int priority);
+int priorityqueue_insert(struct priority_queue_t *queue, void *value, int priority);
 
 /**
  * @brief Removes the object with a matching value from the queue.
@@ -89,4 +89,4 @@ int queue_insert(struct priority_queue_t *queue, void *value, int priority);
  * @param value 
  * @return int 
  */
-int queue_remove(struct priority_queue_t *queue, void *value);
+int priorityqueue_remove(struct priority_queue_t *queue, void *value);

include/queue.h

@@ -0,0 +1,53 @@
+#pragma once
+
+struct queue_node_t;
+
+/**
+ * @brief A last-in-first-out queue.
+ * 
+ */
+struct queue_t
+{
+    /**
+     * @brief The number of objects stored in this queue.
+     * 
+     */
+    unsigned int count;
+
+    /**
+     * @brief A link to the first node stored in this queue.
+     * 
+     */
+    struct queue_node_t *first;
+
+    /**
+     * @brief A link to the last node stored in this queue.
+     * 
+     */
+    struct queue_node_t *last;
+};
+
+/**
+ * @brief Inserts a new item at the end of the queue.
+ * 
+ * @param queue 
+ * @param ptr 
+ */
+void queue_insert(struct queue_t *queue, void *ptr);
+
+/**
+ * @brief Removes the next item from the queue and returns it.
+ * 
+ * @param queue 
+ * @return void* 
+ */
+void *queue_get_next(struct queue_t *queue);
+
+/**
+ * @brief Returns the next item on the queue without removing it.
+ * 
+ * @param queue 
+ * @return void* 
+ */
+void *queue_peek(struct queue_t *queue);
+

src/Makefile.am

@@ -1,5 +1,5 @@
 noinst_PROGRAMS = quark-kernel
-quark_kernel_SOURCES = kernel.c mmgr.c priorityqueue.c stdio.c string.c elf.c syscalls.c heap.c memmap.c avltree.c
+quark_kernel_SOURCES = kernel.c mmgr.c priorityqueue.c stdio.c string.c elf.c syscalls.c heap.c memmap.c avltree.c queue.c
 quark_kernel_LDADD = -lgcc
 quark_kernel_CFLAGS = -I$(top_srcdir)/include -ffreestanding -mgeneral-regs-only -O0 -Wall -ggdb
 quark_kernel_LDFLAGS = -nostdlib

src/kernel.c

@@ -214,7 +214,7 @@ int add_process(void *program_entry, int priority, physaddr_t address_space)
     new_process->page_table = address_space;
     new_process->state = initial_context;
     kernel.process_table = avl_insert(kernel.process_table, new_process->resource_id, new_process);
-    queue_insert(&kernel.priority_queue, new_process, new_process->priority);
+    priorityqueue_insert(&kernel.priority_queue, new_process, new_process->priority);
     kernel.next_pid++;
     return new_process->resource_id;
 }
@@ -223,9 +223,9 @@ struct process_context_t *next_process()
 {  
     if(kernel.active_process != NULL)
     {
-        queue_insert(&kernel.priority_queue, kernel.active_process, kernel.active_process->priority);
+        priorityqueue_insert(&kernel.priority_queue, kernel.active_process, kernel.active_process->priority);
     }
-    kernel.active_process = extract_min(&kernel.priority_queue);
+    kernel.active_process = priorityqueue_extract_min(&kernel.priority_queue);
     if(kernel.active_process != NULL)
     {
         paging_load_address_space(kernel.active_process->page_table);
@@ -247,7 +247,7 @@ int terminate_process(size_t process_id)
         kernel.active_process = NULL;
     }
     kernel.process_table = avl_remove(kernel.process_table, process_id);
-    queue_remove(&kernel.priority_queue, process);
+    priorityqueue_remove(&kernel.priority_queue, process);
     destroy_context(process->state);
     kfree(process);
     return S_OK;

src/priorityqueue.c

@@ -38,7 +38,7 @@ int construct_priority_queue(struct priority_queue_t *queue, int capacity)
     return S_OK;
 }
 
-void *extract_min(struct priority_queue_t *queue)
+void *priorityqueue_extract_min(struct priority_queue_t *queue)
 {
     if(queue->size == 0)
         return NULL;
@@ -49,7 +49,7 @@ void *extract_min(struct priority_queue_t *queue)
     return value;
 }
 
-int queue_insert(struct priority_queue_t *queue, void *value, int priority)
+int priorityqueue_insert(struct priority_queue_t *queue, void *value, int priority)
 {
     if(queue->size == queue->capacity)
         return S_OUT_OF_MEMORY;
@@ -65,7 +65,7 @@ int queue_insert(struct priority_queue_t *queue, void *value, int priority)
     return S_OK;
 }
 
-int queue_remove(struct priority_queue_t *queue, void *value)
+int priorityqueue_remove(struct priority_queue_t *queue, void *value)
 {
     for(size_t i = 0; i < queue->size; i++)
     {

src/queue.c

@@ -0,0 +1,53 @@
+#include "queue.h"
+#include "heap.h"
+
+struct queue_node_t
+{
+    /**
+     * @brief Pointer to the user-defined object this node refers to.
+     * 
+     */
+    void *ptr;
+
+    /**
+     * @brief Link to the next node in the queue.
+     * 
+     */
+    struct queue_node_t *next;
+};
+
+void queue_insert(struct queue_t *queue, void *ptr)
+{
+    struct queue_node_t *node = kmalloc(sizeof(struct queue_node_t));
+    node->ptr = ptr;
+    node->next = NULL;
+    if(queue->last == NULL)
+    {
+        queue->first = queue->last = node;
+    }
+    else
+    {
+        queue->last->next = node;
+        queue->last = node;
+    }
+    queue->count++;
+}
+
+void *queue_get_next(struct queue_t *queue)
+{
+    struct queue_node_t *node = queue->first;
+    queue->first = node->next;
+    if(queue->first == NULL)
+    {
+        queue->last = NULL;
+    }
+    queue->count--;
+    void *ptr = node->ptr;
+    kfree(node);
+    return ptr;
+}
+
+void *queue_peek(struct queue_t *queue)
+{
+    return queue->first->ptr;
+}