Refactored the phase optimization functionality into a separate module

core/net/mac/phase.c

@@ -0,0 +1,116 @@
+/*
+ * Copyright (c) 2010, Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the Institute nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * This file is part of the Contiki operating system.
+ *
+ * $Id: phase.c,v 1.1 2010/02/18 20:58:59 adamdunkels Exp $
+ */
+
+/**
+ * \file
+ *         Common functionality for phase optimization in duty cycling radio protocols
+ * \author
+ *         Adam Dunkels <adam@sics.se>
+ */
+
+#include "net/mac/phase.h"
+#include "net/rime/packetbuf.h"
+
+/*---------------------------------------------------------------------------*/
+void
+phase_register(const struct phase_list *list,
+                   const rimeaddr_t * neighbor, rtimer_clock_t time)
+{
+  struct phase *e;
+
+  /* If we have an entry for this neighbor already, we renew it. */
+  for(e = list_head(*list->list); e != NULL; e = e->next) {
+    if(rimeaddr_cmp(neighbor, &e->neighbor)) {
+      e->time = time;
+      break;
+    }
+  }
+  /* No matching phase was found, so we allocate a new one. */
+  if(e == NULL) {
+    e = memb_alloc(list->memb);
+    if(e == NULL) {
+      /* We could not allocate memory for this phase, so we drop
+         the last item on the list and reuse it for our phase. */
+      e = list_chop(*list->list);
+    }
+    rimeaddr_copy(&e->neighbor, neighbor);
+    e->time = time;
+    list_push(*list->list, e);
+  }
+}
+/*---------------------------------------------------------------------------*/
+void
+phase_wait(struct phase_list *list,
+           const rimeaddr_t *neighbor, rtimer_clock_t cycle_time,
+           rtimer_clock_t wait_before)
+{
+  struct phase *e;
+  
+  /* We go through the list of phases to find if we have recorded
+     an phase with this particular neighbor. If so, we can compute
+     the time for the next expected phase and setup a ctimer to
+     switch on the radio just before the phase. */
+  for(e = list_head(*list->list); e != NULL; e = e->next) {
+    const rimeaddr_t *neighbor = packetbuf_addr(PACKETBUF_ADDR_RECEIVER);
+
+    if(rimeaddr_cmp(neighbor, &e->neighbor)) {
+      rtimer_clock_t wait, now, expected;
+
+      /* We expect phases to happen every CYCLE_TIME time
+         units. The next expected phase is at time e->time +
+         CYCLE_TIME. To compute a relative offset, we subtract
+         with clock_time(). Because we are only interested in turning
+         on the radio within the CYCLE_TIME period, we compute the
+         waiting time with modulo CYCLE_TIME. */
+
+      now = RTIMER_NOW();
+      wait = (rtimer_clock_t)((e->time - now) & (cycle_time - 1));
+      if(wait < wait_before) {
+        wait += cycle_time;
+      }
+      expected = now + wait - wait_before;
+      if(!RTIMER_CLOCK_LT(expected, now)) {
+        /* Wait until the receiver is expected to be awake */
+        while(RTIMER_CLOCK_LT(RTIMER_NOW(), expected));
+      }
+    }
+  }
+}
+/*---------------------------------------------------------------------------*/
+void
+phase_init(struct phase_list *list)
+{
+  list_init(*list->list);
+  memb_init(list->memb);
+}
+/*---------------------------------------------------------------------------*/

core/net/mac/phase.h

@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 2010, Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the Institute nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * This file is part of the Contiki operating system.
+ *
+ * $Id: phase.h,v 1.1 2010/02/18 20:58:59 adamdunkels Exp $
+ */
+
+/**
+ * \file
+ *         Common functionality for phase optimization in duty cycling radio protocols
+ * \author
+ *         Adam Dunkels <adam@sics.se>
+ */
+
+#ifndef PHASE_H
+#define PHASE_H
+
+#include "net/rime/rimeaddr.h"
+#include "sys/rtimer.h"
+#include "lib/list.h"
+#include "lib/memb.h"
+
+struct phase {
+  struct phase *next;
+  rimeaddr_t neighbor;
+  rtimer_clock_t time;
+};
+
+struct phase_list {
+  list_t *list;
+  struct memb *memb;
+};
+
+#define PHASE_LIST(name, num) LIST(phase_list_list);                              \
+                              MEMB(phase_list_memb, struct phase, num);           \
+                              struct phase_list name = { &phase_list_list, &phase_list_memb }
+
+void phase_init(struct phase_list *list);
+void phase_wait(struct phase_list *list,  const rimeaddr_t *neighbor,
+                rtimer_clock_t cycle_time, rtimer_clock_t wait_before);
+void phase_register(const struct phase_list *list, const rimeaddr_t * neighbor,
+                    rtimer_clock_t time);
+
+
+#endif /* PHASE_H */