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-rw-r--r--libqpol/src/queue.c183
1 files changed, 183 insertions, 0 deletions
diff --git a/libqpol/src/queue.c b/libqpol/src/queue.c
new file mode 100644
index 0000000..18667d5
--- /dev/null
+++ b/libqpol/src/queue.c
@@ -0,0 +1,183 @@
+/**
+ * @file
+ *
+ * This file is a copy of queue.c from NSA's CVS repository.
+ *
+ * Author : Stephen Smalley, <sds@epoch.ncsc.mil>
+ */
+
+/* FLASK */
+
+/*
+ * Implementation of the double-ended queue type.
+ */
+
+#include <stdlib.h>
+#include "queue.h"
+
+queue_t queue_create(void)
+{
+ queue_t q;
+
+ q = (queue_t) malloc(sizeof(struct queue_info));
+ if (q == NULL)
+ return NULL;
+
+ q->head = q->tail = NULL;
+
+ return q;
+}
+
+int queue_insert(queue_t q, queue_element_t e)
+{
+ queue_node_ptr_t newnode;
+
+ if (!q)
+ return -1;
+
+ newnode = (queue_node_ptr_t) malloc(sizeof(struct queue_node));
+ if (newnode == NULL)
+ return -1;
+
+ newnode->element = e;
+ newnode->next = NULL;
+
+ if (q->head == NULL) {
+ q->head = q->tail = newnode;
+ } else {
+ q->tail->next = newnode;
+ q->tail = newnode;
+ }
+
+ return 0;
+}
+
+int queue_push(queue_t q, queue_element_t e)
+{
+ queue_node_ptr_t newnode;
+
+ if (!q)
+ return -1;
+
+ newnode = (queue_node_ptr_t) malloc(sizeof(struct queue_node));
+ if (newnode == NULL)
+ return -1;
+
+ newnode->element = e;
+ newnode->next = NULL;
+
+ if (q->head == NULL) {
+ q->head = q->tail = newnode;
+ } else {
+ newnode->next = q->head;
+ q->head = newnode;
+ }
+
+ return 0;
+}
+
+queue_element_t queue_remove(queue_t q)
+{
+ queue_node_ptr_t node;
+ queue_element_t e;
+
+ if (!q)
+ return NULL;
+
+ if (q->head == NULL)
+ return NULL;
+
+ node = q->head;
+ q->head = q->head->next;
+ if (q->head == NULL)
+ q->tail = NULL;
+
+ e = node->element;
+ free(node);
+
+ return e;
+}
+
+queue_element_t queue_head(queue_t q)
+{
+ if (!q)
+ return NULL;
+
+ if (q->head == NULL)
+ return NULL;
+
+ return q->head->element;
+}
+
+void queue_destroy(queue_t q)
+{
+ queue_node_ptr_t p, temp;
+
+ if (!q)
+ return;
+
+ p = q->head;
+ while (p != NULL) {
+ temp = p;
+ p = p->next;
+ free(temp);
+ }
+
+ free(q);
+}
+
+int queue_map(queue_t q, int (*f) (queue_element_t, void *), void *vp)
+{
+ queue_node_ptr_t p;
+ int ret;
+
+ if (!q)
+ return 0;
+
+ p = q->head;
+ while (p != NULL) {
+ ret = f(p->element, vp);
+ if (ret)
+ return ret;
+ p = p->next;
+ }
+ return 0;
+}
+
+void queue_map_remove_on_error(queue_t q, int (*f) (queue_element_t, void *), void (*g) (queue_element_t, void *), void *vp)
+{
+ queue_node_ptr_t p, last, temp;
+ int ret;
+
+ if (!q)
+ return;
+
+ last = NULL;
+ p = q->head;
+ while (p != NULL) {
+ ret = f(p->element, vp);
+ if (ret) {
+ if (last) {
+ last->next = p->next;
+ if (last->next == NULL)
+ q->tail = last;
+ } else {
+ q->head = p->next;
+ if (q->head == NULL)
+ q->tail = NULL;
+ }
+
+ temp = p;
+ p = p->next;
+ g(temp->element, vp);
+ free(temp);
+ } else {
+ last = p;
+ p = p->next;
+ }
+ }
+
+ return;
+}
+
+/* FLASK */