fix sadness

[ppos.git] / queue / queue.c

diff --git a/queue/queue.c b/queue/queue.c
index 949e461138be84c972487adcd98addb9a8a9aa5b..2aed9eb54cae7f70b4021011226bf4b40adeba7c 100644 (file)
--- a/queue/queue.c
+++ b/queue/queue.c
@@ -3,3 +3,217 @@
 // Versão 2.0 -- Junho de 2025
 
 // Implementação do TAD fila genérica
+
+/* PEDRO HENRIQUE FRIEDRICH RAMOS : GRR20243133 */
+
+#include "queue.h"
+#include <stdio.h>
+#include <stdlib.h>
+
+struct node_t
+{
+  void *item;
+  struct node_t *next;
+};
+
+struct queue_t
+{
+  struct node_t *head;
+  struct node_t *tail;
+  struct node_t *iterator;
+  int size;
+};
+
+static inline struct node_t *
+node_create (void)
+{
+  return calloc (1, sizeof (struct node_t));
+}
+
+static inline void
+node_destroy (struct node_t *node)
+{
+  free (node);
+}
+
+struct queue_t *
+queue_create (void)
+{
+  return calloc (1, sizeof (struct queue_t));
+}
+
+int
+queue_destroy (struct queue_t *queue)
+{
+  struct node_t *n, *next;
+
+  if (!queue)
+    return ERROR;
+
+  n = queue->head;
+
+  while (n)
+    {
+      next = n->next;
+      node_destroy (n);
+      n = next;
+    }
+
+  free (queue);
+  return NOERROR;
+}
+
+int
+queue_add (struct queue_t *queue, void *item)
+{
+  struct node_t *n;
+
+  if (!queue || !item)
+    return ERROR;
+
+  if (!(n = node_create ()))
+    return ERROR;
+
+  n->item = item;
+  ++queue->size;
+
+  if (!queue->head)
+    {
+      queue->head = queue->tail = queue->iterator = n;
+      return NOERROR;
+    }
+
+  queue->tail = queue->tail->next = n;
+  return NOERROR;
+}
+
+int
+queue_del (struct queue_t *queue, void *item)
+{
+  struct node_t *n, *prev;
+
+  if (!queue || !item)
+    return ERROR;
+
+  if (!(n = queue->head))
+    return ERROR;
+
+  prev = NULL;
+
+  while (n && n->item != item)
+    {
+      prev = n;
+      n = n->next;
+    }
+
+  if (!n) /* not found */
+    return ERROR;
+
+  if (prev)
+    prev->next = n->next;
+
+  if (queue->head == n)
+    queue->head = n->next;
+
+  if (queue->tail == n)
+    queue->tail = prev;
+
+  if (queue->iterator == n)
+    queue->iterator = n->next;
+
+  --queue->size;
+  node_destroy (n);
+  return NOERROR;
+}
+
+bool
+queue_has (struct queue_t *queue, void *item)
+{
+  struct node_t *n;
+
+  if (!queue || !item)
+    return false;
+
+  if (!(n = queue->head))
+    return false;
+
+  while (n->item != item && (n = n->next))
+    ;
+
+  return n != NULL;
+}
+
+int
+queue_size (struct queue_t *queue)
+{
+  if (!queue)
+    return ERROR;
+
+  return queue->size;
+}
+
+void *
+queue_head (struct queue_t *queue)
+{
+  if (!queue || !queue->head)
+    return NULL;
+
+  queue->iterator = queue->head;
+
+  return queue->head->item;
+}
+
+void *
+queue_next (struct queue_t *queue)
+{
+  if (!queue || !queue->iterator)
+    return NULL;
+
+  queue->iterator = queue->iterator->next;
+
+  if (!queue->iterator)
+    return NULL;
+
+  return queue->iterator->item;
+}
+
+void *
+queue_item (struct queue_t *queue)
+{
+  if (!queue || !queue->iterator)
+    return NULL;
+
+  return queue->iterator->item;
+}
+
+void
+queue_print (char *name, struct queue_t *queue, void (func) (void *))
+{
+  struct node_t *n;
+
+  if (!name)
+    return;
+
+  printf ("%s: ", name);
+
+  if (!queue)
+    {
+      puts ("undef");
+      return;
+    }
+
+  fputs ("[ ", stdout);
+
+  for (n = queue->head; n; n = n->next)
+    {
+      if (func)
+        func (n->item);
+
+      else
+        fputs ("undef", stdout);
+
+      putchar (' ');
+    }
+
+  printf ("] (%d items)\n", queue->size);
+}