Initial revision
diff --git a/gtp/queue.h b/gtp/queue.h
new file mode 100644
index 0000000..076a3ef
--- /dev/null
+++ b/gtp/queue.h
@@ -0,0 +1,77 @@
+/* 
+ *  OpenGGSN - Gateway GPRS Support Node
+ *  Copyright (C) 2002 Mondru AB.
+ * 
+ *  The contents of this file may be used under the terms of the GNU
+ *  General Public License Version 2, provided that the above copyright
+ *  notice and this permission notice is included in all copies or
+ *  substantial portions of the software.
+ * 
+ *  The initial developer of the original code is
+ *  Jens Jakobsen <jj@openggsn.org>
+ * 
+ *  Contributor(s):
+ * 
+ */
+
+/*
+ * Queue.c
+ * Reliable delivery of signalling messages
+ */
+
+#ifndef _QUEUE_H
+#define _QUEUE_H
+
+#define QUEUE_DEBUG 0    /* Print debug information */
+
+#define QUEUE_SIZE 256 /* Size of retransmission queue */
+#define QUEUE_HASH_SIZE 65536 /* Size of hash table (2^16) */
+
+struct qmsg_t {           /* Holder for queued packets */
+  int state;              /* 0=empty, 1=full */
+  uint16_t seq;           /* The sequence number */
+  u_int8_t type;         /* The type of packet */
+  void *aid;              /* Application specific pointer */
+  union gtp_packet p;     /* The packet stored */
+  int l;                  /* Length of the packet */
+  struct sockaddr_in peer;/* Address packet was sent to / received from */
+  struct qmsg_t *seqnext; /* Pointer to next in sequence hash list */
+  int next;               /* Pointer to the next in queue. -1: Last */
+  int prev;               /* Pointer to the previous in queue. -1: First */
+  int this;               /* Pointer to myself */
+  time_t timeout;         /* When do we retransmit this packet? */
+  int retrans;            /* How many times did we retransmit this? */
+};
+
+struct queue_t {
+  struct qmsg_t qmsga[QUEUE_SIZE]; /* Array holding signalling messages */
+  void *hashseq[QUEUE_HASH_SIZE];    /* Hash array */
+  int next;               /* Next location in queue to use */
+  int first;              /* First packet in queue (oldest timeout) */
+  int last;               /* Last packet in queue (youngest timeout) */
+};
+
+
+/*  Allocates and initialises new queue structure */
+int queue_new(struct queue_t **queue);
+/*  Deallocates queue structure */
+int queue_free(struct queue_t *queue);
+/* Find a new queue element. Return EOF if allready full */
+int queue_newmsg(struct queue_t *queue, struct qmsg_t **qmsg,
+		 struct sockaddr_in *peer, uint16_t seq);
+/* Remove an element from the queue. */
+int queue_freemsg(struct queue_t *queue, struct qmsg_t *qmsg);
+/* Move an element to the back of the queue */
+int queue_back(struct queue_t *queue, struct qmsg_t *qmsg);
+/* Get the first element in the queue (oldest) */
+int queue_getfirst(struct queue_t *queue, struct qmsg_t **qmsg);
+/* Get the element with a particular sequence number */
+int queue_seqget(struct queue_t *queue, struct qmsg_t **qmsg,
+		 struct sockaddr_in  *peer, uint16_t seq);
+/* Free message based on sequence number */
+int queue_freemsg_seq(struct queue_t *queue, struct sockaddr_in *peer,
+		      uint16_t seq, uint8_t *type, void **aid);
+
+
+#endif	/* !_QUEUE_H */
+