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diff --git a/src/fs/gnunet-service-fs_cp.h b/src/fs/gnunet-service-fs_cp.h
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+/*
+     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_cp.h
+ * @brief API to handle 'connected peers'
+ * @author Christian Grothoff
+ */
+#ifndef GNUNET_SERVICE_FS_CP_H
+#define GNUNET_SERVICE_FS_CP_H
+
+#include "fs.h"
+#include "gnunet-service-fs.h"
+
+
+/**
+ * Maximum number of outgoing messages we queue per peer.
+ *
+ * Performance measurements for 2 peer setup for 50 MB file
+ * (with MAX_DATASTORE_QUEUE = 1 and RETRY_PROBABILITY_INV = 1):
+ *
+ *   2: 1700 kb/s, 1372 kb/s
+ *   8: 2117 kb/s, 1284 kb/s, 1112 kb/s
+ *  16: 3500 kb/s, 3200 kb/s, 3388 kb/s
+ *  32: 3441 kb/s, 3163 kb/s, 3277 kb/s
+ * 128: 1700 kb/s; 2010 kb/s, 3383 kb/s, 1156 kb/s
+ *
+ * Conclusion: 16 seems to be a pretty good value (stable
+ * and high performance, no excessive memory use).
+ */
+#define MAX_QUEUE_PER_PEER 16
+
+/**
+ * Length of the P2P success tracker.  Note that having a very long
+ * list can also hurt performance.
+ */
+#define P2P_SUCCESS_LIST_SIZE 8
+
+/**
+ * Length of the CS-2-P success tracker.  Note that
+ * having a very long list can also hurt performance.
+ */
+#define CS2P_SUCCESS_LIST_SIZE 8
+
+
+/**
+ * Performance data kept for a peer.
+ */
+struct GSF_PeerPerformanceData
+{
+
+  /**
+   * Transport performance data.
+   */
+  struct GNUNET_ATS_Information *atsi;
+
+  /**
+   * List of the last clients for which this peer successfully
+   * answered a query.
+   */
+  struct GSF_LocalClient *last_client_replies[CS2P_SUCCESS_LIST_SIZE];
+
+  /**
+   * List of the last PIDs for which
+   * this peer successfully answered a query;
+   * We use 0 to indicate no successful reply.
+   */
+  GNUNET_PEER_Id last_p2p_replies[P2P_SUCCESS_LIST_SIZE];
+
+  /**
+   * Average delay between sending the peer a request and
+   * getting a reply (only calculated over the requests for
+   * which we actually got a reply).   Calculated
+   * as a moving average: new_delay = ((n-1)*last_delay+curr_delay) / n
+   */
+  struct GNUNET_TIME_Relative avg_reply_delay;
+
+  /**
+   * If we get content we already have from this peer, for how
+   * long do we block him?  Adjusted based on the fraction of
+   * redundant data we receive, between 1s and 1h.
+   */
+  struct GNUNET_TIME_Relative migration_delay;
+
+  /**
+   * Point in time until which this peer does not want us to migrate content
+   * to it.
+   */
+  struct GNUNET_TIME_Absolute migration_blocked_until;
+
+  /**
+   * Transmission times for the last MAX_QUEUE_PER_PEER
+   * requests for this peer.  Used as a ring buffer, current
+   * offset is stored in 'last_request_times_off'.  If the
+   * oldest entry is more recent than the 'avg_delay', we should
+   * not send any more requests right now.
+   */
+  struct GNUNET_TIME_Absolute last_request_times[MAX_QUEUE_PER_PEER];
+
+  /**
+   * How long does it typically take for us to transmit a message
+   * to this peer?  (delay between the request being issued and
+   * the callback being invoked).
+   */
+  struct GNUNET_LOAD_Value *transmission_delay;
+
+  /**
+   * Average priority of successful replies.  Calculated
+   * as a moving average: new_avg = ((n-1)*last_avg+curr_prio) / n
+   */
+  double avg_priority;
+
+  /**
+   * The peer's identity.
+   */
+  GNUNET_PEER_Id pid;
+
+  /**
+   * Trust rating for this peer
+   */
+  uint32_t trust;
+
+  /**
+   * Number of pending queries (replies are not counted)
+   */
+  unsigned int pending_queries;
+
+  /**
+   * Number of pending replies (queries are not counted)
+   */
+  unsigned int pending_replies;
+
+};
+
+
+/**
+ * Signature of function called on a connected peer.
+ *
+ * @param cls closure
+ * @param peer identity of the peer
+ * @param cp handle to the connected peer record
+ * @param perf peer performance data
+ */
+typedef void (*GSF_ConnectedPeerIterator) (void *cls,
+                                           const struct GNUNET_PeerIdentity *
+                                           peer, struct GSF_ConnectedPeer * cp,
+                                           const struct GSF_PeerPerformanceData
+                                           * ppd);
+
+
+/**
+ * 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)
+ */
+typedef size_t (*GSF_GetMessageCallback) (void *cls, size_t buf_size,
+                                          void *buf);
+
+
+/**
+ * Signature of function called on a reservation success or failure.
+ *
+ * @param cls closure
+ * @param cp handle to the connected peer record
+ * @param success GNUNET_YES on success, GNUNET_NO on failure
+ */
+typedef void (*GSF_PeerReserveCallback) (void *cls,
+                                         struct GSF_ConnectedPeer * cp,
+                                         int success);
+
+
+/**
+ * Handle to cancel a transmission request.
+ */
+struct GSF_PeerTransmitHandle;
+
+
+/**
+ * A peer connected to us.  Setup the connected peer
+ * records.
+ *
+ * @param peer identity of peer that connected
+ * @param atsi performance data for the connection
+ * @param atsi_count number of records in 'atsi'
+ * @return handle to connected peer entry
+ */
+struct GSF_ConnectedPeer *
+GSF_peer_connect_handler_ (const struct GNUNET_PeerIdentity *peer,
+                           const struct GNUNET_ATS_Information *atsi,
+                           unsigned int atsi_count);
+
+
+/**
+ * Get a handle for a connected peer.
+ *
+ * @param peer peer's identity
+ * @return NULL if this peer is not currently connected
+ */
+struct GSF_ConnectedPeer *
+GSF_peer_get_ (const struct GNUNET_PeerIdentity *peer);
+
+
+/**
+ * Transmit a message to the given peer as soon as possible.
+ * If the peer disconnects before the transmission can happen,
+ * the callback is invoked with a 'NULL' buffer.
+ *
+ * @param cp target peer
+ * @param is_query is this a query (GNUNET_YES) or content (GNUNET_NO)
+ * @param priority how important is this request?
+ * @param timeout when does this request timeout (call gmc with error)
+ * @param size number of bytes we would like to send to the peer
+ * @param gmc function to call to get the message
+ * @param gmc_cls closure for gmc
+ * @return handle to cancel request
+ */
+struct GSF_PeerTransmitHandle *
+GSF_peer_transmit_ (struct GSF_ConnectedPeer *cp, int is_query,
+                    uint32_t priority, struct GNUNET_TIME_Relative timeout,
+                    size_t size, GSF_GetMessageCallback gmc, void *gmc_cls);
+
+
+/**
+ * Cancel an earlier request for transmission.
+ *
+ * @param pth request to cancel
+ */
+void
+GSF_peer_transmit_cancel_ (struct GSF_PeerTransmitHandle *pth);
+
+
+/**
+ * Report on receiving a reply; update the performance record of the given peer.
+ *
+ * @param cp responding peer (will be updated)
+ * @param request_time time at which the original query was transmitted
+ * @param request_priority priority of the original request
+ */
+void
+GSF_peer_update_performance_ (struct GSF_ConnectedPeer *cp,
+                              struct GNUNET_TIME_Absolute request_time,
+                              uint32_t request_priority);
+
+
+/**
+ * Report on receiving a reply in response to an initiating client.
+ * Remember that this peer is good for this client.
+ *
+ * @param cp responding peer (will be updated)
+ * @param initiator_client local client on responsible for query
+ */
+void
+GSF_peer_update_responder_client_ (struct GSF_ConnectedPeer *cp,
+                                   struct GSF_LocalClient *initiator_client);
+
+
+/**
+ * Report on receiving a reply in response to an initiating peer.
+ * Remember that this peer is good for this initiating peer.
+ *
+ * @param cp responding peer (will be updated)
+ * @param initiator_peer other peer responsible for query
+ */
+void
+GSF_peer_update_responder_peer_ (struct GSF_ConnectedPeer *cp,
+                                 const struct GSF_ConnectedPeer
+                                 *initiator_peer);
+
+
+/**
+ * Handle P2P "MIGRATION_STOP" message.
+ *
+ * @param cls closure, always NULL
+ * @param other the other peer involved (sender or receiver, NULL
+ *        for loopback messages where we are both sender and receiver)
+ * @param message the actual message
+ * @param atsi performance information
+ * @param atsi_count number of records in 'atsi'
+ * @return GNUNET_OK to keep the connection open,
+ *         GNUNET_SYSERR to close it (signal serious error)
+ */
+int
+GSF_handle_p2p_migration_stop_ (void *cls,
+                                const struct GNUNET_PeerIdentity *other,
+                                const struct GNUNET_MessageHeader *message,
+                                const struct GNUNET_ATS_Information *atsi,
+                                unsigned int atsi_count);
+
+
+/**
+ * Handle P2P "QUERY" message.  Only responsible for creating the
+ * request entry itself and setting up reply callback and cancellation
+ * on peer disconnect.  Does NOT execute the actual request strategy
+ * (planning) or local database operations.
+ *
+ * @param other the other peer involved (sender or receiver, NULL
+ *        for loopback messages where we are both sender and receiver)
+ * @param message the actual message
+ * @return pending request handle, NULL on error
+ */
+struct GSF_PendingRequest *
+GSF_handle_p2p_query_ (const struct GNUNET_PeerIdentity *other,
+                       const struct GNUNET_MessageHeader *message);
+
+
+/**
+ * Return the performance data record for the given peer
+ *
+ * @param cp peer to query
+ * @return performance data record for the peer
+ */
+struct GSF_PeerPerformanceData *
+GSF_get_peer_performance_data_ (struct GSF_ConnectedPeer *cp);
+
+
+/**
+ * Ask a peer to stop migrating data to us until the given point
+ * in time.
+ *
+ * @param cp peer to ask
+ * @param block_time until when to block
+ */
+void
+GSF_block_peer_migration_ (struct GSF_ConnectedPeer *cp,
+                           struct GNUNET_TIME_Absolute block_time);
+
+
+/**
+ * A peer disconnected from us.  Tear down the connected peer
+ * record.
+ *
+ * @param cls unused
+ * @param peer identity of peer that connected
+ */
+void
+GSF_peer_disconnect_handler_ (void *cls,
+                              const struct GNUNET_PeerIdentity *peer);
+
+
+/**
+ * Notification that a local client disconnected.  Clean up all of our
+ * references to the given handle.
+ *
+ * @param lc handle to the local client (henceforth invalid)
+ */
+void
+GSF_handle_local_client_disconnect_ (const struct GSF_LocalClient *lc);
+
+
+/**
+ * Notify core about a preference we have for the given peer
+ * (to allocate more resources towards it).  The change will
+ * be communicated the next time we reserve bandwidth with
+ * core (not instantly).
+ *
+ * @param cp peer to reserve bandwidth from
+ * @param pref preference change
+ */
+void
+GSF_connected_peer_change_preference_ (struct GSF_ConnectedPeer *cp,
+                                       uint64_t pref);
+
+
+/**
+ * Obtain the identity of a connected peer.
+ *
+ * @param cp peer to reserve bandwidth from
+ * @param id identity to set (written to)
+ */
+void
+GSF_connected_peer_get_identity_ (const struct GSF_ConnectedPeer *cp,
+                                  struct GNUNET_PeerIdentity *id);
+
+
+/**
+ * Iterate over all connected peers.
+ *
+ * @param it function to call for each peer
+ * @param it_cls closure for it
+ */
+void
+GSF_iterate_connected_peers_ (GSF_ConnectedPeerIterator it, void *it_cls);
+
+
+/**
+ * Initialize peer management subsystem.
+ */
+void
+GSF_connected_peer_init_ (void);
+
+
+/**
+ * Shutdown peer management subsystem.
+ */
+void
+GSF_connected_peer_done_ (void);
+
+
+#endif
+/* end of gnunet-service-fs_cp.h */