1 files changed, 775 insertions, 0 deletions
diff --git a/src/fs/gnunet-service-fs_pe.c b/src/fs/gnunet-service-fs_pe.c
new file mode 100644
index 0000000..71b0fc0
--- /dev/null
+++ b/src/fs/gnunet-service-fs_pe.c
@@ -0,0 +1,775 @@
+/*
+     This file is part of GNUnet.
+     (C) 2011 Christian Grothoff (and other contributing authors)
+
+     GNUnet 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 3, or (at your
+     option) any later version.
+
+     GNUnet 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 GNUnet; see the file COPYING.  If not, write to the
+     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+     Boston, MA 02111-1307, USA.
+*/
+
+/**
+ * @file fs/gnunet-service-fs_pe.c
+ * @brief API to manage query plan
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include "gnunet-service-fs.h"
+#include "gnunet-service-fs_cp.h"
+#include "gnunet-service-fs_pe.h"
+#include "gnunet-service-fs_pr.h"
+
+
+/**
+ * List of GSF_PendingRequests this request plan
+ * participates with.
+ */
+struct PendingRequestList;
+
+/**
+ * Transmission plan for a peer.
+ */
+struct PeerPlan;
+
+
+/**
+ * DLL of request plans a particular pending request is
+ * involved with.
+ */
+struct GSF_RequestPlanReference
+{
+
+  /**
+   * This is a doubly-linked list.
+   */
+  struct GSF_RequestPlanReference *next;
+
+  /**
+   * This is a doubly-linked list.
+   */
+  struct GSF_RequestPlanReference *prev;
+
+  /**
+   * Associated request plan.
+   */
+  struct GSF_RequestPlan *rp;
+
+  /**
+   * Corresponding PendingRequestList.
+   */
+  struct PendingRequestList *prl;
+};
+
+
+/**
+ * List of GSF_PendingRequests this request plan
+ * participates with.
+ */
+struct PendingRequestList
+{
+
+  /**
+   * This is a doubly-linked list.
+   */
+  struct PendingRequestList *next;
+
+  /**
+   * This is a doubly-linked list.
+   */
+  struct PendingRequestList *prev;
+
+  /**
+   * Associated pending request.
+   */
+  struct GSF_PendingRequest *pr;
+
+  /**
+   * Corresponding GSF_RequestPlanReference.
+   */
+  struct GSF_RequestPlanReference *rpr;
+
+};
+
+
+/**
+ * Information we keep per request per peer.  This is a doubly-linked
+ * list (with head and tail in the 'struct GSF_PendingRequestData')
+ * with one entry in each heap of each 'struct PeerPlan'.  Each
+ * entry tracks information relevant for this request and this peer.
+ */
+struct GSF_RequestPlan
+{
+
+  /**
+   * This is a doubly-linked list.
+   */
+  struct GSF_RequestPlan *next;
+
+  /**
+   * This is a doubly-linked list.
+   */
+  struct GSF_RequestPlan *prev;
+
+  /**
+   * Heap node associated with this request and this peer.
+   */
+  struct GNUNET_CONTAINER_HeapNode *hn;
+
+  /**
+   * The transmission plan for a peer that this request is associated with.
+   */
+  struct PeerPlan *pp;
+
+  /**
+   * Head of list of associated pending requests.
+   */
+  struct PendingRequestList *prl_head;
+
+  /**
+   * Tail of list of associated pending requests.
+   */
+  struct PendingRequestList *prl_tail;
+
+  /**
+   * Earliest time we'd be happy to (re)transmit this request.
+   */
+  struct GNUNET_TIME_Absolute earliest_transmission;
+
+  /**
+   * When was the last time we transmitted this request to this peer? 0 for never.
+   */
+  struct GNUNET_TIME_Absolute last_transmission;
+
+  /**
+   * Current priority for this request for this target.
+   */
+  uint64_t priority;
+
+  /**
+   * How often did we transmit this request to this peer?
+   */
+  unsigned int transmission_counter;
+
+};
+
+
+/**
+ * Transmission plan for a peer.
+ */
+struct PeerPlan
+{
+  /**
+   * Heap with pending queries (struct GSF_RequestPlan), higher weights mean higher priority.
+   */
+  struct GNUNET_CONTAINER_Heap *priority_heap;
+
+  /**
+   * Heap with pending queries (struct GSF_RequestPlan), by transmission time, lowest first.
+   */
+  struct GNUNET_CONTAINER_Heap *delay_heap;
+
+  /**
+   * Map of queries to plan entries.  All entries in the priority_heap or delay_heap
+   * should be in the plan map.  Note that it IS possible for the plan map to have
+   * multiple entries for the same query.
+   */
+  struct GNUNET_CONTAINER_MultiHashMap *plan_map;
+
+  /**
+   * Current transmission request handle.
+   */
+  struct GSF_PeerTransmitHandle *pth;
+
+  /**
+   * Peer for which this is the plan.
+   */
+  struct GSF_ConnectedPeer *cp;
+
+  /**
+   * Current task for executing the plan.
+   */
+  GNUNET_SCHEDULER_TaskIdentifier task;
+};
+
+
+/**
+ * Hash map from peer identities to PeerPlans.
+ */
+static struct GNUNET_CONTAINER_MultiHashMap *plans;
+
+/**
+ * Sum of all transmission counters (equals total delay for all plan entries).
+ */
+static unsigned long long total_delay;
+
+/**
+ * Number of plan entries.
+ */
+static unsigned long long plan_count;
+
+
+/**
+ * Return the query (key in the plan_map) for the given request plan.
+ *
+ * @param rp a request plan
+ * @return the associated query
+ */
+static const GNUNET_HashCode *
+get_rp_key (struct GSF_RequestPlan *rp)
+{
+  return &GSF_pending_request_get_data_ (rp->prl_head->pr)->query;
+}
+
+
+/**
+ * Figure out when and how to transmit to the given peer.
+ *
+ * @param cls the 'struct GSF_ConnectedPeer' for transmission
+ * @param tc scheduler context
+ */
+static void
+schedule_peer_transmission (void *cls,
+                            const struct GNUNET_SCHEDULER_TaskContext *tc);
+
+
+/**
+ * Insert the given request plan into the heap with the appropriate weight.
+ *
+ * @param pp associated peer's plan
+ * @param rp request to plan
+ */
+static void
+plan (struct PeerPlan *pp, struct GSF_RequestPlan *rp)
+{
+#define N ((double)128.0)
+  /**
+   * Running average delay we currently impose.
+   */
+  static double avg_delay;
+
+  struct GSF_PendingRequestData *prd;
+  struct GNUNET_TIME_Relative delay;
+
+  GNUNET_assert (rp->pp == pp);
+  GNUNET_STATISTICS_set (GSF_stats,
+                         gettext_noop ("# average retransmission delay (ms)"),
+                         total_delay * 1000LL / plan_count, GNUNET_NO);
+  prd = GSF_pending_request_get_data_ (rp->prl_head->pr);
+
+  if (rp->transmission_counter < 8)
+    delay =
+        GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS,
+                                       rp->transmission_counter);
+  else if (rp->transmission_counter < 32)
+    delay =
+        GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS,
+                                       8 +
+                                       (1LL << (rp->transmission_counter - 8)));
+  else
+    delay =
+        GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS,
+                                       8 + (1LL << 24));
+  delay.rel_value =
+      GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
+                                delay.rel_value + 1);
+  /* Add 0.01 to avg_delay to avoid division-by-zero later */
+  avg_delay = (((avg_delay * (N - 1.0)) + delay.rel_value) / N) + 0.01;
+
+  /*
+   * For the priority, we need to consider a few basic rules:
+   * 1) if we just started requesting (delay is small), we should
+   * virtually always have a priority of zero.
+   * 2) for requests with average latency, our priority should match
+   * the average priority observed on the network
+   * 3) even the longest-running requests should not be WAY out of
+   * the observed average (thus we bound by a factor of 2)
+   * 4) we add +1 to the observed average priority to avoid everyone
+   * staying put at zero (2 * 0 = 0...).
+   *
+   * Using the specific calculation below, we get:
+   *
+   * delay = 0 => priority = 0;
+   * delay = avg delay => priority = running-average-observed-priority;
+   * delay >> avg_delay => priority = 2 * running-average-observed-priority;
+   *
+   * which satisfies all of the rules above.
+   *
+   * Note: M_PI_4 = PI/4 = arctan(1)
+   */
+  rp->priority =
+      round ((GSF_current_priorities +
+              1.0) * atan (delay.rel_value / avg_delay)) / M_PI_4;
+  /* Note: usage of 'round' and 'atan' requires -lm */
+
+  if (rp->transmission_counter != 0)
+    delay.rel_value += TTL_DECREMENT;
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Considering (re)transmission number %u in %llu ms\n",
+              (unsigned int) rp->transmission_counter,
+              (unsigned long long) delay.rel_value);
+  rp->earliest_transmission = GNUNET_TIME_relative_to_absolute (delay);
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Earliest (re)transmission for `%s' in %us\n",
+              GNUNET_h2s (&prd->query), rp->transmission_counter);
+  GNUNET_assert (rp->hn == NULL);
+  if (GNUNET_TIME_absolute_get_remaining (rp->earliest_transmission).rel_value
+      == 0)
+    rp->hn = GNUNET_CONTAINER_heap_insert (pp->priority_heap, rp, rp->priority);
+  else
+    rp->hn =
+        GNUNET_CONTAINER_heap_insert (pp->delay_heap, rp,
+                                      rp->earliest_transmission.abs_value);
+  GNUNET_assert (GNUNET_YES ==
+                 GNUNET_CONTAINER_multihashmap_contains_value (pp->plan_map,
+                                                               get_rp_key (rp),
+                                                               rp));
+  if (GNUNET_SCHEDULER_NO_TASK != pp->task)
+    GNUNET_SCHEDULER_cancel (pp->task);
+  pp->task = GNUNET_SCHEDULER_add_now (&schedule_peer_transmission, pp);
+#undef N
+}
+
+
+/**
+ * Get the pending request with the highest TTL from the given plan.
+ *
+ * @param rp plan to investigate
+ * @return pending request with highest TTL
+ */
+struct GSF_PendingRequest *
+get_latest (const struct GSF_RequestPlan *rp)
+{
+  struct GSF_PendingRequest *ret;
+  struct PendingRequestList *prl;
+
+  prl = rp->prl_head;
+  ret = prl->pr;
+  prl = prl->next;
+  while (NULL != prl)
+  {
+    if (GSF_pending_request_get_data_ (prl->pr)->ttl.abs_value >
+        GSF_pending_request_get_data_ (ret)->ttl.abs_value)
+      ret = prl->pr;
+    prl = prl->next;
+  }
+  return ret;
+}
+
+
+/**
+ * Function called to get a message for transmission.
+ *
+ * @param cls closure
+ * @param buf_size number of bytes available in buf
+ * @param buf where to copy the message, NULL on error (peer disconnect)
+ * @return number of bytes copied to 'buf', can be 0 (without indicating an error)
+ */
+static size_t
+transmit_message_callback (void *cls, size_t buf_size, void *buf)
+{
+  struct PeerPlan *pp = cls;
+  struct GSF_RequestPlan *rp;
+  size_t msize;
+
+  pp->pth = NULL;
+  if (NULL == buf)
+  {
+    /* failed, try again... */
+    pp->task = GNUNET_SCHEDULER_add_now (&schedule_peer_transmission, pp);
+    GNUNET_STATISTICS_update (GSF_stats,
+                              gettext_noop
+                              ("# transmission failed (core has no bandwidth)"),
+                              1, GNUNET_NO);
+    return 0;
+  }
+  rp = GNUNET_CONTAINER_heap_peek (pp->priority_heap);
+  if (NULL == rp)
+  {
+    pp->task = GNUNET_SCHEDULER_add_now (&schedule_peer_transmission, pp);
+    return 0;
+  }
+  msize = GSF_pending_request_get_message_ (get_latest (rp), buf_size, buf);
+  if (msize > buf_size)
+  {
+    /* buffer to small (message changed), try again */
+    pp->task = GNUNET_SCHEDULER_add_now (&schedule_peer_transmission, pp);
+    return 0;
+  }
+  /* remove from root, add again elsewhere... */
+  GNUNET_assert (rp == GNUNET_CONTAINER_heap_remove_root (pp->priority_heap));
+  rp->hn = NULL;
+  rp->last_transmission = GNUNET_TIME_absolute_get ();
+  rp->transmission_counter++;
+  total_delay++;
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Executing plan %p executed %u times, planning retransmission\n",
+              rp, rp->transmission_counter);
+  plan (pp, rp);
+  GNUNET_STATISTICS_update (GSF_stats,
+                            gettext_noop
+                            ("# query messages sent to other peers"), 1,
+                            GNUNET_NO);
+  return msize;
+}
+
+
+/**
+ * Figure out when and how to transmit to the given peer.
+ *
+ * @param cls the 'struct PeerPlan'
+ * @param tc scheduler context
+ */
+static void
+schedule_peer_transmission (void *cls,
+                            const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+  struct PeerPlan *pp = cls;
+  struct GSF_RequestPlan *rp;
+  size_t msize;
+  struct GNUNET_TIME_Relative delay;
+
+  pp->task = GNUNET_SCHEDULER_NO_TASK;
+  if (pp->pth != NULL)
+  {
+    GSF_peer_transmit_cancel_ (pp->pth);
+    pp->pth = NULL;
+  }
+  /* move ready requests to priority queue */
+  while ((NULL != (rp = GNUNET_CONTAINER_heap_peek (pp->delay_heap))) &&
+         (GNUNET_TIME_absolute_get_remaining
+          (rp->earliest_transmission).rel_value == 0))
+  {
+    GNUNET_assert (rp == GNUNET_CONTAINER_heap_remove_root (pp->delay_heap));
+    rp->hn = GNUNET_CONTAINER_heap_insert (pp->priority_heap, rp, rp->priority);
+  }
+  if (0 == GNUNET_CONTAINER_heap_get_size (pp->priority_heap))
+  {
+    /* priority heap (still) empty, check for delay... */
+    rp = GNUNET_CONTAINER_heap_peek (pp->delay_heap);
+    if (NULL == rp)
+    {
+      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "No active requests for plan %p.\n",
+                  pp);
+      return;                   /* both queues empty */
+    }
+    delay = GNUNET_TIME_absolute_get_remaining (rp->earliest_transmission);
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                "Sleeping for %llu ms before retrying requests on plan %p.\n",
+                (unsigned long long) delay.rel_value, pp);
+    GNUNET_STATISTICS_set (GSF_stats, gettext_noop ("# delay heap timeout"),
+                           delay.rel_value, GNUNET_NO);
+
+    pp->task =
+        GNUNET_SCHEDULER_add_delayed (delay, &schedule_peer_transmission, pp);
+    return;
+  }
+  GNUNET_STATISTICS_update (GSF_stats, gettext_noop ("# query plans executed"),
+                            1, GNUNET_NO);
+  /* process from priority heap */
+  rp = GNUNET_CONTAINER_heap_peek (pp->priority_heap);
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Executing query plan %p\n", rp);
+  GNUNET_assert (NULL != rp);
+  msize = GSF_pending_request_get_message_ (get_latest (rp), 0, NULL);
+  pp->pth =
+      GSF_peer_transmit_ (pp->cp, GNUNET_YES, rp->priority,
+                          GNUNET_TIME_UNIT_FOREVER_REL, msize,
+                          &transmit_message_callback, pp);
+  GNUNET_assert (NULL != pp->pth);
+}
+
+
+/**
+ * Closure for 'merge_pr'.
+ */
+struct MergeContext
+{
+
+  struct GSF_PendingRequest *pr;
+
+  int merged;
+
+};
+
+
+/**
+ * Iterator that checks if an equivalent request is already
+ * present for this peer.
+ *
+ * @param cls closure
+ * @param query the query
+ * @param element request plan stored at the node
+ * @return GNUNET_YES if we should continue to iterate,
+ *         GNUNET_NO if not (merge success)
+ */
+static int
+merge_pr (void *cls, const GNUNET_HashCode * query, void *element)
+{
+  struct MergeContext *mpr = cls;
+  struct GSF_RequestPlan *rp = element;
+  struct GSF_PendingRequestData *prd;
+  struct GSF_RequestPlanReference *rpr;
+  struct PendingRequestList *prl;
+  struct GSF_PendingRequest *latest;
+
+  if (GNUNET_OK !=
+      GSF_pending_request_is_compatible_ (mpr->pr, rp->prl_head->pr))
+    return GNUNET_YES;
+  /* merge new request with existing request plan */
+  rpr = GNUNET_malloc (sizeof (struct GSF_RequestPlanReference));
+  prl = GNUNET_malloc (sizeof (struct PendingRequestList));
+  rpr->rp = rp;
+  rpr->prl = prl;
+  prl->rpr = rpr;
+  prl->pr = mpr->pr;
+  prd = GSF_pending_request_get_data_ (mpr->pr);
+  GNUNET_CONTAINER_DLL_insert (prd->rpr_head, prd->rpr_tail, rpr);
+  GNUNET_CONTAINER_DLL_insert (rp->prl_head, rp->prl_tail, prl);
+  mpr->merged = GNUNET_YES;
+  GNUNET_STATISTICS_update (GSF_stats, gettext_noop ("# requests merged"), 1,
+                            GNUNET_NO);
+  latest = get_latest (rp);
+  if (GSF_pending_request_get_data_ (latest)->ttl.abs_value <
+      prd->ttl.abs_value)
+  {
+    GNUNET_STATISTICS_update (GSF_stats, gettext_noop ("# requests refreshed"),
+                              1, GNUNET_NO);
+    rp->transmission_counter = 0;       /* reset */
+  }
+  return GNUNET_NO;
+}
+
+
+/**
+ * Create a new query plan entry.
+ *
+ * @param cp peer with the entry
+ * @param pr request with the entry
+ */
+void
+GSF_plan_add_ (struct GSF_ConnectedPeer *cp, struct GSF_PendingRequest *pr)
+{
+  struct GNUNET_PeerIdentity id;
+  struct PeerPlan *pp;
+  struct GSF_PendingRequestData *prd;
+  struct GSF_RequestPlan *rp;
+  struct GSF_RequestPlanReference *rpr;
+  struct PendingRequestList *prl;
+  struct MergeContext mpc;
+
+  GNUNET_assert (NULL != cp);
+  GSF_connected_peer_get_identity_ (cp, &id);
+  pp = GNUNET_CONTAINER_multihashmap_get (plans, &id.hashPubKey);
+  if (NULL == pp)
+  {
+    pp = GNUNET_malloc (sizeof (struct PeerPlan));
+    pp->plan_map = GNUNET_CONTAINER_multihashmap_create (128);
+    pp->priority_heap =
+        GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MAX);
+    pp->delay_heap =
+        GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
+    pp->cp = cp;
+    GNUNET_CONTAINER_multihashmap_put (plans, &id.hashPubKey, pp,
+                                       GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
+  }
+  mpc.merged = GNUNET_NO;
+  mpc.pr = pr;
+  GNUNET_CONTAINER_multihashmap_get_multiple (pp->plan_map,
+                                              &GSF_pending_request_get_data_
+                                              (pr)->query, &merge_pr, &mpc);
+  if (mpc.merged != GNUNET_NO)
+    return;
+  GNUNET_CONTAINER_multihashmap_get_multiple (pp->plan_map,
+                                              &GSF_pending_request_get_data_
+                                              (pr)->query, &merge_pr, &mpc);
+  if (mpc.merged != GNUNET_NO)
+    return;
+  plan_count++;
+  GNUNET_STATISTICS_update (GSF_stats, gettext_noop ("# query plan entries"), 1,
+                            GNUNET_NO);
+  prd = GSF_pending_request_get_data_ (pr);
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Planning transmission of query `%s' to peer `%s'\n",
+              GNUNET_h2s (&prd->query), GNUNET_i2s (&id));
+  rp = GNUNET_malloc (sizeof (struct GSF_RequestPlan));
+  rpr = GNUNET_malloc (sizeof (struct GSF_RequestPlanReference));
+  prl = GNUNET_malloc (sizeof (struct PendingRequestList));
+  rpr->rp = rp;
+  rpr->prl = prl;
+  prl->rpr = rpr;
+  prl->pr = pr;
+  GNUNET_CONTAINER_DLL_insert (prd->rpr_head, prd->rpr_tail, rpr);
+  GNUNET_CONTAINER_DLL_insert (rp->prl_head, rp->prl_tail, prl);
+  rp->pp = pp;
+  GNUNET_assert (GNUNET_YES ==
+                 GNUNET_CONTAINER_multihashmap_put (pp->plan_map,
+                                                    get_rp_key (rp), rp,
+                                                    GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE));
+  plan (pp, rp);
+}
+
+
+/**
+ * Notify the plan about a peer being no longer available;
+ * destroy all entries associated with this peer.
+ *
+ * @param cp connected peer
+ */
+void
+GSF_plan_notify_peer_disconnect_ (const struct GSF_ConnectedPeer *cp)
+{
+  struct GNUNET_PeerIdentity id;
+  struct PeerPlan *pp;
+  struct GSF_RequestPlan *rp;
+  struct GSF_PendingRequestData *prd;
+  struct PendingRequestList *prl;
+
+  GSF_connected_peer_get_identity_ (cp, &id);
+  pp = GNUNET_CONTAINER_multihashmap_get (plans, &id.hashPubKey);
+  if (NULL == pp)
+    return;                     /* nothing was ever planned for this peer */
+  GNUNET_assert (GNUNET_YES ==
+                 GNUNET_CONTAINER_multihashmap_remove (plans, &id.hashPubKey,
+                                                       pp));
+  if (NULL != pp->pth)
+    GSF_peer_transmit_cancel_ (pp->pth);
+  if (GNUNET_SCHEDULER_NO_TASK != pp->task)
+  {
+    GNUNET_SCHEDULER_cancel (pp->task);
+    pp->task = GNUNET_SCHEDULER_NO_TASK;
+  }
+  while (NULL != (rp = GNUNET_CONTAINER_heap_remove_root (pp->priority_heap)))
+  {
+    GNUNET_break (GNUNET_YES ==
+                  GNUNET_CONTAINER_multihashmap_remove (pp->plan_map,
+                                                        get_rp_key (rp), rp));
+    while (NULL != (prl = rp->prl_head))
+    {
+      GNUNET_CONTAINER_DLL_remove (rp->prl_head, rp->prl_tail, prl);
+      prd = GSF_pending_request_get_data_ (prl->pr);
+      GNUNET_CONTAINER_DLL_remove (prd->rpr_head, prd->rpr_tail, prl->rpr);
+      GNUNET_free (prl->rpr);
+      GNUNET_free (prl);
+    }
+    GNUNET_free (rp);
+  }
+  GNUNET_CONTAINER_heap_destroy (pp->priority_heap);
+  while (NULL != (rp = GNUNET_CONTAINER_heap_remove_root (pp->delay_heap)))
+  {
+    GNUNET_break (GNUNET_YES ==
+                  GNUNET_CONTAINER_multihashmap_remove (pp->plan_map,
+                                                        get_rp_key (rp), rp));
+    while (NULL != (prl = rp->prl_head))
+    {
+      GNUNET_CONTAINER_DLL_remove (rp->prl_head, rp->prl_tail, prl);
+      prd = GSF_pending_request_get_data_ (prl->pr);
+      GNUNET_CONTAINER_DLL_remove (prd->rpr_head, prd->rpr_tail, prl->rpr);
+      GNUNET_free (prl->rpr);
+      GNUNET_free (prl);
+    }
+    GNUNET_free (rp);
+  }
+  GNUNET_STATISTICS_set (GSF_stats, gettext_noop ("# query plan entries"),
+                         plan_count, GNUNET_NO);
+
+  GNUNET_CONTAINER_heap_destroy (pp->delay_heap);
+  GNUNET_CONTAINER_multihashmap_destroy (pp->plan_map);
+  GNUNET_free (pp);
+}
+
+/**
+ * Get the last transmission attempt time for the request plan list
+ * referenced by 'rpr_head', that was sent to 'sender'
+ *
+ * @param rpr_head request plan reference list to check.
+ * @param sender the peer that we've sent the request to.
+ * @param result the timestamp to fill.
+ * @return GNUNET_YES if 'result' was changed, GNUNET_NO otherwise.
+ */
+int
+GSF_request_plan_reference_get_last_transmission_ (
+    struct GSF_RequestPlanReference *rpr_head, struct GSF_ConnectedPeer *sender,
+    struct GNUNET_TIME_Absolute *result)
+{
+  struct GSF_RequestPlanReference *rpr;
+  for (rpr = rpr_head; rpr; rpr = rpr->next)
+  {
+    if (rpr->rp->pp->cp == sender)
+    {
+      *result = rpr->rp->last_transmission;
+      return GNUNET_YES;
+    }
+  }
+  return GNUNET_NO;
+}
+
+/**
+ * Notify the plan about a request being done; destroy all entries
+ * associated with this request.
+ *
+ * @param pr request that is done
+ */
+void
+GSF_plan_notify_request_done_ (struct GSF_PendingRequest *pr)
+{
+  struct GSF_RequestPlan *rp;
+  struct GSF_PendingRequestData *prd;
+  struct GSF_RequestPlanReference *rpr;
+
+  prd = GSF_pending_request_get_data_ (pr);
+  while (NULL != (rpr = prd->rpr_head))
+  {
+    GNUNET_CONTAINER_DLL_remove (prd->rpr_head, prd->rpr_tail, rpr);
+    rp = rpr->rp;
+    GNUNET_CONTAINER_DLL_remove (rp->prl_head, rp->prl_tail, rpr->prl);
+    if (NULL == rp->prl_head)
+    {
+      GNUNET_CONTAINER_heap_remove_node (rp->hn);
+      plan_count--;
+      GNUNET_break (GNUNET_YES ==
+                    GNUNET_CONTAINER_multihashmap_remove (rp->pp->plan_map,
+                                                          &GSF_pending_request_get_data_
+                                                          (rpr->prl->pr)->query,
+                                                          rp));
+      GNUNET_free (rp);
+    }
+    GNUNET_free (rpr->prl);
+    GNUNET_free (rpr);
+  }
+  GNUNET_STATISTICS_set (GSF_stats, gettext_noop ("# query plan entries"),
+                         plan_count, GNUNET_NO);
+}
+
+
+/**
+ * Initialize plan subsystem.
+ */
+void
+GSF_plan_init ()
+{
+  plans = GNUNET_CONTAINER_multihashmap_create (256);
+}
+
+
+/**
+ * Shutdown plan subsystem.
+ */
+void
+GSF_plan_done ()
+{
+  GNUNET_assert (0 == GNUNET_CONTAINER_multihashmap_size (plans));
+  GNUNET_CONTAINER_multihashmap_destroy (plans);
+}
+
+
+
+/* end of gnunet-service-fs_pe.h */