1 files changed, 109 insertions, 0 deletions
diff --git a/polyp/queue.c b/polyp/queue.c
new file mode 100644
index 00000000..9befd475
--- /dev/null
+++ b/polyp/queue.c
@@ -0,0 +1,109 @@
+/* $Id$ */
+
+/***
+  This file is part of polypaudio.
+ 
+  polypaudio is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published
+  by the Free Software Foundation; either version 2 of the License,
+  or (at your option) any later version.
+ 
+  polypaudio is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  General Public License for more details.
+ 
+  You should have received a copy of the GNU General Public License
+  along with polypaudio; if not, write to the Free Software
+  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+  USA.
+***/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <assert.h>
+#include <stdlib.h>
+
+#include "queue.h"
+
+struct queue_entry {
+    struct queue_entry *next;
+    void *data;
+};
+
+struct pa_queue {
+    struct queue_entry *front, *back;
+    unsigned length;
+};
+
+struct pa_queue* pa_queue_new(void) {
+    struct pa_queue *q = malloc(sizeof(struct pa_queue));
+    assert(q);
+    q->front = q->back = NULL;
+    q->length = 0;
+    return q;
+}
+
+void pa_queue_free(struct pa_queue* q, void (*destroy)(void *p, void *userdata), void *userdata) {
+    struct queue_entry *e;
+    assert(q);
+
+    e = q->front;
+    while (e) {
+        struct queue_entry *n = e->next;
+
+        if (destroy)
+            destroy(e->data, userdata);
+
+        free(e);
+        e = n;
+    }
+
+    free(q);
+}
+
+void pa_queue_push(struct pa_queue *q, void *p) {
+    struct queue_entry *e;
+
+    e = malloc(sizeof(struct queue_entry));
+
+    e->data = p;
+    e->next = NULL;
+
+    if (q->back)
+        q->back->next = e;
+    else {
+        assert(!q->front);
+        q->front = e;
+    }
+
+    q->back = e;
+    q->length++;
+}
+
+void* pa_queue_pop(struct pa_queue *q) {
+    void *p;
+    struct queue_entry *e;
+    assert(q);
+
+    if (!(e = q->front))
+        return NULL;
+
+    q->front = e->next;
+    if (q->back == e)
+        q->back = NULL;
+
+    p = e->data;
+    free(e);
+
+    q->length--;
+    
+    return p;
+}
+
+int pa_queue_is_empty(struct pa_queue *q) {
+    assert(q);
+    return q->length == 0;
+}