-proposed mesh2 API draft

1 files changed, 357 insertions, 0 deletions

diff --git a/src/include/gnunet_mesh2_service.h b/src/include/gnunet_mesh2_service.h
new file mode 100644
index 000000000..b4631a8ab
--- /dev/null
+++ b/src/include/gnunet_mesh2_service.h
@@ -0,0 +1,357 @@
+/*
+     This file is part of GNUnet.
+     (C) 2009, 2010, 2011, 2012, 2013 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 include/gnunet_mesh_service.h
+ * @brief mesh service; establish tunnels to distant peers
+ * @author Christian Grothoff
+ */
+
+#ifndef GNUNET_MESH_SERVICE_H
+#define GNUNET_MESH_SERVICE_H
+
+#ifdef __cplusplus
+extern "C"
+{
+#if 0                           /* keep Emacsens' auto-indent happy */
+}
+#endif
+#endif
+
+#include "gnunet_util_lib.h"
+#include "gnunet_transport_service.h"
+
+/**
+ * Version number of GNUnet-mesh API.
+ */
+#define GNUNET_MESH_VERSION 0x00000001
+
+
+/**
+ * Opaque handle to the service.
+ */
+struct GNUNET_MESH_Handle;
+
+/**
+ * Opaque handle to a tunnel.
+ */
+struct GNUNET_MESH_Tunnel;
+
+
+/**
+ * Functions with this signature are called whenever a message is
+ * received.
+ *
+ * @param cls closure (set from GNUNET_MESH_connect)
+ * @param tunnel connection to the other end
+ * @param tunnel_ctx place to store local state associated with the tunnel
+ * @param sender who sent the message
+ * @param message the actual message
+ * @param atsi performance data for the connection
+ * @return GNUNET_OK to keep the connection open,
+ *         GNUNET_SYSERR to close it (signal serious error)
+ */
+typedef int (*GNUNET_MESH_MessageCallback) (void *cls,
+                                            struct GNUNET_MESH_Tunnel * tunnel,
+                                            void **tunnel_ctx,
+                                            const struct GNUNET_PeerIdentity *
+                                            sender,
+                                            const struct GNUNET_MessageHeader *
+                                            message,
+                                            const struct GNUNET_ATS_Information
+                                            * atsi);
+
+
+/**
+ * Message handler.  Each struct specifies how to handle on particular
+ * type of message received.
+ */
+struct GNUNET_MESH_MessageHandler
+{
+  /**
+   * Function to call for messages of "type".
+   */
+  GNUNET_MESH_MessageCallback callback;
+
+  /**
+   * Type of the message this handler covers.
+   */
+  uint16_t type;
+
+  /**
+   * Expected size of messages of this type.  Use 0 for variable-size.
+   * If non-zero, messages of the given type will be discarded if they
+   * do not have the right size.
+   */
+  uint16_t expected_size;
+
+};
+
+
+/**
+ * Method called whenever another peer has added us to a tunnel
+ * the other peer initiated.
+ * Only called (once) upon reception of data with a message type which was
+ * subscribed to in GNUNET_MESH_connect. A call to GNUNET_MESH_tunnel_destroy
+ * causes te tunnel to be ignored and no further notifications are sent about
+ * the same tunnel.
+ *
+ * @param cls closure
+ * @param tunnel new handle to the tunnel
+ * @param initiator peer that started the tunnel
+ * @param atsi performance information for the tunnel
+ * @return initial tunnel context for the tunnel
+ *         (can be NULL -- that's not an error)
+ */
+typedef void *(GNUNET_MESH_InboundTunnelNotificationHandler) (void *cls,
+                                                              struct
+                                                              GNUNET_MESH_Tunnel
+                                                              * tunnel,
+                                                              const struct
+                                                              GNUNET_PeerIdentity
+                                                              * initiator,
+                                                              const struct
+                                                              GNUNET_ATS_Information
+                                                              * atsi);
+
+
+/**
+ * Function called whenever an inbound tunnel is destroyed.  Should clean up
+ * any associated state.  This function is NOT called if the client has
+ * explicitly asked for the tunnel to be destroyed using
+ * GNUNET_MESH_tunnel_destroy. It must NOT call GNUNET_MESH_tunnel_destroy on
+ * the tunnel.
+ *
+ * @param cls closure (set from GNUNET_MESH_connect)
+ * @param tunnel connection to the other end (henceforth invalid)
+ * @param tunnel_ctx place where local state associated
+ *                   with the tunnel is stored
+ */
+typedef void (GNUNET_MESH_TunnelEndHandler) (void *cls,
+                                             const struct GNUNET_MESH_Tunnel *
+                                             tunnel, void *tunnel_ctx);
+
+
+/**
+ * Connect to the mesh service.
+ *
+ * @param cfg configuration to use
+ * @param cls closure for the various callbacks that follow
+ *            (including handlers in the handlers array)
+ * @param new_tunnel function called when an *inbound* tunnel is created
+ * @param cleaner function called when an *inbound* tunnel is destroyed by the
+ *                remote peer, it is *not* called if GNUNET_MESH_tunnel_destroy
+ *                is called on the tunnel
+ * @param handlers callbacks for messages we care about, NULL-terminated
+ *                note that the mesh is allowed to drop notifications about
+ *                inbound messages if the client does not process them fast
+ *                enough (for this notification type, a bounded queue is used)
+ * @return handle to the mesh service NULL on error
+ *         (in this case, init is never called)
+ */
+struct GNUNET_MESH_Handle *
+GNUNET_MESH_connect (const struct GNUNET_CONFIGURATION_Handle *cfg, void *cls,
+                     GNUNET_MESH_InboundTunnelNotificationHandler new_tunnel,
+                     GNUNET_MESH_TunnelEndHandler cleaner,
+                     const struct GNUNET_MESH_MessageHandler *handlers);
+
+
+/**
+ * Disconnect from the mesh service. All tunnels will be destroyed. All tunnel
+ * disconnect callbacks will be called on any still connected peers, notifying
+ * about their disconnection. The registered inbound tunnel cleaner will be
+ * called should any inbound tunnels still exist.
+ *
+ * @param handle connection to mesh to disconnect
+ */
+void
+GNUNET_MESH_disconnect (struct GNUNET_MESH_Handle *handle);
+
+
+/**
+ * Create a new tunnel (we're initiator and will be allowed to add/remove peers
+ * and to broadcast).
+ *
+ * @param h mesh handle
+ * @param tunnel_ctx client's tunnel context to associate with the tunnel
+ * @param peer peer identity the tunnel should go to
+ * @return handle to the tunnel
+ */
+struct GNUNET_MESH_Tunnel *
+GNUNET_MESH_tunnel_create (struct GNUNET_MESH_Handle *h, 
+                           void *tunnel_ctx,
+                           const struct GNUNET_PeerIdentity *peer);
+
+
+/**
+ * Destroy an existing tunnel. The existing callback for the tunnel will NOT
+ * be called.
+ *
+ * @param tunnel tunnel handle
+ */
+void
+GNUNET_MESH_tunnel_destroy (struct GNUNET_MESH_Tunnel *tunnel);
+
+
+/**
+ * Turn on/off the buffering status of the tunnel.
+ * 
+ * @param tunnel Tunnel affected.
+ * @param buffer GNUNET_YES to turn buffering on (default),
+ *               GNUNET_NO otherwise.
+ */
+void
+GNUNET_MESH_tunnel_buffer (struct GNUNET_MESH_Tunnel *tunnel, int buffer);
+
+
+/**
+ * Handle for a transmission request.
+ */
+struct GNUNET_MESH_TransmitHandle;
+
+
+/**
+ * Ask the mesh to call "notify" once it is ready to transmit the
+ * given number of bytes to the specified tunnel.
+ * Only one call can be active at any time, to issue another request,
+ * wait for the callback or cancel the current request.
+ *
+ * @param tunnel tunnel to use for transmission
+ * @param cork is corking allowed for this transmission?
+ * @param maxdelay how long can the message wait?
+ * @param notify_size how many bytes of buffer space does notify want?
+ * @param notify function to call when buffer space is available;
+ *        will be called with NULL on timeout or if the overall queue
+ *        for this peer is larger than queue_size and this is currently
+ *        the message with the lowest priority
+ * @param notify_cls closure for notify
+ * @return non-NULL if the notify callback was queued,
+ *         NULL if we can not even queue the request (insufficient
+ *         memory); if NULL is returned, "notify" will NOT be called.
+ */
+struct GNUNET_MESH_TransmitHandle *
+GNUNET_MESH_notify_transmit_ready (struct GNUNET_MESH_Tunnel *tunnel, int cork,
+                                   struct GNUNET_TIME_Relative maxdelay,
+                                   size_t notify_size,
+                                   GNUNET_CONNECTION_TransmitReadyNotify notify,
+                                   void *notify_cls);
+
+
+/**
+ * Cancel the specified transmission-ready notification.
+ *
+ * @param th handle that was returned by "notify_transmit_ready".
+ */
+void
+GNUNET_MESH_notify_transmit_ready_cancel (struct GNUNET_MESH_TransmitHandle
+                                          *th);
+
+
+/**
+ * Method called to retrieve information about each tunnel the mesh peer
+ * is aware of.
+ *
+ * @param cls Closure.
+ * @param tunnel_number Tunnel number.
+ * @param origin that started the tunnel (owner).
+ * @param target other endpoint of the tunnel
+ */
+typedef void (*GNUNET_MESH_TunnelsCB) (void *cls,
+                                       uint32_t tunnel_number,
+                                       const struct GNUNET_PeerIdentity *origin,
+                                       const struct GNUNET_PeerIdentity *target);
+
+
+/**
+ * Method called to retrieve information about a specific tunnel the mesh peer
+ * is aware of, including all transit nodes.
+ *
+ * @param cls Closure.
+ * @param peer Peer in the tunnel's tree.
+ * @param parent Parent of the current peer. All 0 when peer is root.
+ */
+typedef void (*GNUNET_MESH_TunnelCB) (void *cls,
+                                      const struct GNUNET_PeerIdentity *peer,
+                                      const struct GNUNET_PeerIdentity *parent);
+
+
+/**
+ * Request information about the running mesh peer.
+ * The callback will be called for every tunnel known to the service,
+ * listing all active peers that blong to the tunnel.
+ *
+ * If called again on the same handle, it will overwrite the previous
+ * callback and cls. To retrieve the cls, monitor_cancel must be
+ * called first.
+ *
+ * WARNING: unstable API, likely to change in the future!
+ *
+ * @param h Handle to the mesh peer.
+ * @param callback Function to call with the requested data.
+ * @param callback_cls Closure for @c callback.
+ */
+void
+GNUNET_MESH_get_tunnels (struct GNUNET_MESH_Handle *h,
+                         GNUNET_MESH_TunnelsCB callback,
+                         void *callback_cls);
+
+
+/**
+ * Request information about a specific tunnel of the running mesh peer.
+ *
+ * WARNING: unstable API, likely to change in the future!
+ *
+ * @param h Handle to the mesh peer.
+ * @param initiator ID of the owner of the tunnel.
+ * @param tunnel_number Tunnel number.
+ * @param callback Function to call with the requested data.
+ * @param callback_cls Closure for @c callback.
+ */
+void
+GNUNET_MESH_show_tunnel (struct GNUNET_MESH_Handle *h,
+                         struct GNUNET_PeerIdentity *initiator,
+                         uint32_t tunnel_number,
+                         GNUNET_MESH_TunnelCB callback,
+                         void *callback_cls);
+
+
+/**
+ * Cancel a monitor request. The monitor callback will not be called.
+ *
+ * WARNING: unstable API, likely to change in the future!
+ *
+ * @param h Mesh handle.
+ *
+ * @return Closure given to GNUNET_MESH_monitor, if any.
+ */
+void *
+GNUNET_MESH_get_tunnels_cancel (struct GNUNET_MESH_Handle *h);
+
+
+#if 0                           /* keep Emacsens' auto-indent happy */
+{
+#endif
+#ifdef __cplusplus
+}
+#endif
+
+/* ifndef GNUNET_MESH_SERVICE_H */
+#endif
+/* end of gnunet_mesh_service.h */