/*
This file is part of GNUnet
- (C) 2013 Christian Grothoff (and other contributing authors)
+ (C) 2013, 2014 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 2, or (at your
+ 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
Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.
*/
-
/**
* @file set/gnunet-service-set.h
* @brief common components for the implementation the different set operations
* @author Florian Dold
+ * @author Christian Grothoff
*/
-
#ifndef GNUNET_SERVICE_SET_H_PRIVATE
#define GNUNET_SERVICE_SET_H_PRIVATE
#include "platform.h"
-#include "gnunet_common.h"
+#include "gnunet_util_lib.h"
#include "gnunet_protocols.h"
#include "gnunet_applications.h"
-#include "gnunet_util_lib.h"
#include "gnunet_core_service.h"
-#include "gnunet_stream_lib.h"
+#include "gnunet_cadet_service.h"
#include "gnunet_set_service.h"
#include "set.h"
-#include "mq.h"
-/* FIXME: cfuchs */
-struct IntersectionState;
+/**
+ * Implementation-specific set state. Used as opaque pointer, and
+ * specified further in the respective implementation.
+ */
+struct SetState;
+/**
+ * Implementation-specific set operation. Used as opaque pointer, and
+ * specified further in the respective implementation.
+ */
+struct OperationState;
/**
- * Extra state required for set union.
+ * A set that supports a specific operation with other peers.
*/
-struct UnionState;
+struct Set;
+/**
+ * Information about an element element in the set. All elements are
+ * stored in a hash-table from their hash-code to their 'struct
+ * Element', so that the remove and add operations are reasonably
+ * fast.
+ */
+struct ElementEntry;
/**
- * A set that supports a specific operation
- * with other peers.
+ * Operation context used to execute a set operation.
*/
-struct Set
+struct Operation;
+
+
+/**
+ * Detail information about an operation.
+ */
+struct OperationSpecification
{
+
/**
- * Client that owns the set.
- * Only one client may own a set.
+ * The remove peer we evaluate the operation with.
*/
- struct GNUNET_SERVER_Client *client;
+ struct GNUNET_PeerIdentity peer;
/**
- * Message queue for the client
+ * Application ID for the operation, used to distinguish
+ * multiple operations of the same type with the same peer.
*/
- struct GNUNET_MQ_MessageQueue *client_mq;
+ struct GNUNET_HashCode app_id;
/**
- * Type of operation supported for this set
+ * Context message, may be NULL.
*/
- uint32_t operation; // use enum from API
+ struct GNUNET_MessageHeader *context_msg;
/**
- * Sets are held in a doubly linked list.
+ * Set associated with the operation, NULL until the spec has been
+ * associated with a set.
*/
- struct Set *next;
+ struct Set *set;
/**
- * Sets are held in a doubly linked list.
+ * Salt to use for the operation.
*/
- struct Set *prev;
+ uint32_t salt;
+
+ /**
+ * Remote peers element count
+ */
+ uint32_t remote_element_count;
+
+ /**
+ * ID used to identify an operation between service and client
+ */
+ uint32_t client_request_id;
+
+ /**
+ * The type of the operation.
+ */
+ enum GNUNET_SET_OperationType operation;
/**
- * Appropriate state for each type of
- * operation.
+ * When are elements sent to the client, and which elements are sent?
*/
- union {
- struct IntersectionState *i;
- struct UnionState *u;
- } state;
+ enum GNUNET_SET_ResultMode result_mode;
};
/**
- * A listener is inhabited by a client, and
- * waits for evaluation requests from remote peers.
+ * Signature of functions that create the implementation-specific
+ * state for a set supporting a specific operation.
+ *
+ * @return a set state specific to the supported operation
+ */
+typedef struct SetState *
+(*CreateImpl) (void);
+
+
+/**
+ * Signature of functions that implement the add/remove functionality
+ * for a set supporting a specific operation.
+ *
+ * @param set implementation-specific set state
+ * @param ee element message from the client
+ */
+typedef void
+(*AddRemoveImpl) (struct SetState *state,
+ struct ElementEntry *ee);
+
+
+/**
+ * Signature of functions that handle disconnection of the remote
+ * peer.
+ *
+ * @param op the set operation, contains implementation-specific data
+ */
+typedef void
+(*PeerDisconnectImpl) (struct Operation *op);
+
+
+/**
+ * Signature of functions that implement the destruction of the
+ * implementation-specific set state.
+ *
+ * @param state the set state, contains implementation-specific data
+ */
+typedef void
+(*DestroySetImpl) (struct SetState *state);
+
+
+/**
+ * Signature of functions that implement accepting a set operation.
+ *
+ * @param op operation that is created by accepting the operation,
+ * should be initialized by the implementation
+ */
+typedef void
+(*OpAcceptImpl) (struct Operation *op);
+
+
+/**
+ * Signature of functions that implement starting the evaluation of
+ * set operations.
+ *
+ * @param op operation that is created, should be initialized to
+ * begin the evaluation
+ * @param opaque_context message to be transmitted to the listener
+ * to convince him to accept, may be NULL
+ */
+typedef void
+(*OpEvaluateImpl) (struct Operation *op,
+ const struct GNUNET_MessageHeader *opaque_context);
+
+
+/**
+ * Signature of functions that implement the message handling for
+ * the different set operations.
+ *
+ * @param op operation state
+ * @param msg received message
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR to
+ * destroy the operation and the tunnel
+ */
+typedef int
+(*MsgHandlerImpl) (struct Operation *op,
+ const struct GNUNET_MessageHeader *msg);
+
+
+/**
+ * Signature of functions that implement operation cancellation
+ *
+ * @param op operation state
+ */
+typedef void
+(*CancelImpl) (struct Operation *op);
+
+
+/**
+ * Dispatch table for a specific set operation. Every set operation
+ * has to implement the callback in this struct.
*/
-struct Listener
+struct SetVT
{
/**
- * Listeners are held in a doubly linked list.
+ * Callback for the set creation.
*/
- struct Listener *next;
+ CreateImpl create;
/**
- * Listeners are held in a doubly linked list.
+ * Callback for element insertion
*/
- struct Listener *prev;
+ AddRemoveImpl add;
/**
- * Client that owns the set.
- * Only one client may own a set.
+ * Callback for element removal.
*/
- struct GNUNET_SERVER_Client *client;
+ AddRemoveImpl remove;
/**
- * Message queue for the client
+ * Callback for accepting a set operation request
*/
- struct GNUNET_MQ_MessageQueue *client_mq;
+ OpAcceptImpl accept;
/**
- * Type of operation supported for this set
+ * Callback for starting evaluation with a remote peer.
*/
- enum GNUNET_SET_OperationType operation;
+ OpEvaluateImpl evaluate;
/**
- * Application id of intereset for this listener.
+ * Callback for destruction of the set state.
*/
- struct GNUNET_HashCode app_id;
+ DestroySetImpl destroy_set;
+
+ /**
+ * Callback for handling operation-specific messages.
+ */
+ MsgHandlerImpl msg_handler;
+
+ /**
+ * Callback for handling the remote peer's disconnect.
+ */
+ PeerDisconnectImpl peer_disconnect;
+
+ /**
+ * Callback for canceling an operation by its ID.
+ */
+ CancelImpl cancel;
};
/**
- * Peer that has connected to us, but is not yet evaluating a set operation.
- * Once the peer has sent a request, and the client has
- * accepted or rejected it, this information will be deleted.
+ * Information about an element element in the set. All elements are
+ * stored in a hash-table from their hash-code to their `struct
+ * Element`, so that the remove and add operations are reasonably
+ * fast.
*/
-struct Incoming
+struct ElementEntry
{
/**
- * Incoming peers are held in a linked list
+ * The actual element. The data for the element
+ * should be allocated at the end of this struct.
*/
- struct Incoming *next;
+ struct GNUNET_SET_Element element;
/**
- * Incoming peers are held in a linked list
+ * Hash of the element. For set union: Will be used to derive the
+ * different IBF keys for different salts.
*/
- struct Incoming *prev;
+ struct GNUNET_HashCode element_hash;
/**
- * Identity of the peer that connected to us
+ * Generation the element was added by the client.
+ * Operations of earlier generations will not consider the element.
*/
- struct GNUNET_PeerIdentity peer;
+ unsigned int generation_added;
/**
- * Socket connected to the peer
+ * Generation the element was removed by the client.
+ * Operations of later generations will not consider the element.
+ * Only valid if @e removed is #GNUNET_YES.
*/
- struct GNUNET_STREAM_Socket *socket;
+ unsigned int generation_removed;
/**
- * Message queue for the peer
+ * #GNUNET_YES if the element has been removed in some generation.
*/
- struct GNUNET_MQ_MessageQueue *mq;
+ int removed;
/**
- * App code, set once the peer has
- * requested an operation
+ * #GNUNET_YES if the element is a remote element, and does not belong
+ * to the operation's set.
*/
- struct GNUNET_HashCode app_id;
+ int remote;
+};
+
+/**
+ * Operation context used to execute a set operation.
+ */
+struct Operation
+{
/**
- * Context message, set once the peer
- * has requested an operation.
+ * V-Table for the operation belonging to the tunnel contest.
+ *
+ * Used for all operation specific operations after receiving the ops request
*/
- struct GNUNET_MessageHeader *context_msg;
+ const struct SetVT *vt;
/**
- * Salt the peer has requested to use for the
- * operation
+ * Tunnel to the peer.
*/
- uint16_t salt;
+ struct GNUNET_CADET_Channel *channel;
/**
- * Operation the other peer wants to do
+ * Message queue for the tunnel.
*/
- enum GNUNET_SET_OperationType operation;
+ struct GNUNET_MQ_Handle *mq;
+
+ /**
+ * Detail information about the set operation, including the set to
+ * use. When 'spec' is NULL, the operation is not yet entirely
+ * initialized.
+ */
+ struct OperationSpecification *spec;
+
+ /**
+ * Operation-specific operation state. Note that the exact
+ * type depends on this being a union or intersection operation
+ * (and thus on @e vt).
+ */
+ struct OperationState *state;
+
+ /**
+ * Evaluate operations are held in a linked list.
+ */
+ struct Operation *next;
+
+ /**
+ * Evaluate operations are held in a linked list.
+ */
+ struct Operation *prev;
+
+ /**
+ * The identity of the requesting peer. Needs to
+ * be stored here as the op spec might not have been created yet.
+ */
+ struct GNUNET_PeerIdentity peer;
+
+ /**
+ * Timeout task, if the incoming peer has not been accepted
+ * after the timeout, it will be disconnected.
+ */
+ GNUNET_SCHEDULER_TaskIdentifier timeout_task;
+
+ /**
+ * Unique request id for the request from a remote peer, sent to the
+ * client, which will accept or reject the request. Set to '0' iff
+ * the request has not been suggested yet.
+ */
+ uint32_t suggest_id;
+
+ /**
+ * #GNUNET_YES if this is not a "real" set operation yet, and we still
+ * need to wait for the other peer to give us more details.
+ */
+ int is_incoming;
+
+ /**
+ * Generation in which the operation handle
+ * was created.
+ */
+ unsigned int generation_created;
/**
- * Unique request id for the request from
- * a remote peer.
+ * Set to #GNUNET_YES if the set service should not free the
+ * operation, as it is still needed (e.g. in some scheduled task).
*/
- uint32_t request_id;
+ int keep;
};
/**
- * Configuration of the local peer
+ * A set that supports a specific operation with other peers.
*/
-extern const struct GNUNET_CONFIGURATION_Handle *configuration;
+struct Set
+{
+ /**
+ * Sets are held in a doubly linked list (in `sets_head` and `sets_tail`).
+ */
+ struct Set *next;
-/**
- * Disconnect a client and free all resources
- * that the client allocated (e.g. Sets or Listeners)
- *
- * @param client the client to disconnect
- */
-void
-_GSS_client_disconnect (struct GNUNET_SERVER_Client *client);
+ /**
+ * Sets are held in a doubly linked list.
+ */
+ struct Set *prev;
+ /**
+ * Client that owns the set. Only one client may own a set,
+ * and there can only be one set per client.
+ */
+ struct GNUNET_SERVER_Client *client;
-struct Set *
-_GSS_union_set_create (void);
+ /**
+ * Message queue for the client.
+ */
+ struct GNUNET_MQ_Handle *client_mq;
+ /**
+ * Virtual table for this set. Determined by the operation type of
+ * this set.
+ *
+ * Used only for Add/remove of elements and when receiving an incoming
+ * operation from a remote peer.
+ */
+ const struct SetVT *vt;
-void
-_GSS_union_evaluate (struct EvaluateMessage *m, struct Set *set);
+ /**
+ * Implementation-specific state.
+ */
+ struct SetState *state;
+ /**
+ * Current state of iterating elements for the client.
+ * NULL if we are not currently iterating.
+ */
+ struct GNUNET_CONTAINER_MultiHashMapIterator *iter;
-void
-_GSS_union_add (struct ElementMessage *m, struct Set *set);
+ /**
+ * Maps `struct GNUNET_HashCode *` to `struct ElementEntry *`.
+ */
+ struct GNUNET_CONTAINER_MultiHashMap *elements;
+ /**
+ * Evaluate operations are held in a linked list.
+ */
+ struct Operation *ops_head;
-void
-_GSS_union_remove (struct ElementMessage *m, struct Set *set);
+ /**
+ * Evaluate operations are held in a linked list.
+ */
+ struct Operation *ops_tail;
+
+ /**
+ * Current generation, that is, number of previously executed
+ * operations on this set
+ */
+ unsigned int current_generation;
+ /**
+ * Type of operation supported for this set
+ */
+ enum GNUNET_SET_OperationType operation;
+
+ /**
+ * Each @e iter is assigned a unique number, so that the client
+ * can distinguish iterations.
+ */
+ uint16_t iteration_id;
+
+};
+
+/**
+ * Destroy the given operation. Call the implementation-specific
+ * cancel function of the operation. Disconnects from the remote
+ * peer. Does not disconnect the client, as there may be multiple
+ * operations per set.
+ *
+ * @param op operation to destroy
+ * @param gc #GNUNET_YES to perform garbage collection on the set
+ */
void
-_GSS_union_accept (struct AcceptMessage *m, struct Set *set,
- struct Incoming *incoming);
+_GSS_operation_destroy (struct Operation *op,
+ int gc);
+
+
+/**
+ * Get the table with implementing functions for set union.
+ *
+ * @return the operation specific VTable
+ */
+const struct SetVT *
+_GSS_union_vt (void);
+
+
+/**
+ * Get the table with implementing functions for set intersection.
+ *
+ * @return the operation specific VTable
+ */
+const struct SetVT *
+_GSS_intersection_vt (void);
#endif