/*
This file is part of GNUnet
- (C) 2013 Christian Grothoff (and other contributing authors)
+ Copyright (C) 2013, 2014 GNUnet e.V.
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
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.
+ Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ Boston, MA 02110-1301, 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_mesh2_service.h"
+#include "gnunet_cadet_service.h"
#include "gnunet_set_service.h"
#include "set.h"
-/* FIXME: cfuchs */
-struct IntersectionState;
-
-
-/* FIXME: cfuchs */
-struct IntersectionOperation;
+/**
+ * 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;
/**
- * State of a union operation being evaluated.
+ * 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 UnionEvaluateOperation;
+struct ElementEntry;
+/**
+ * Operation context used to execute a set operation.
+ */
+struct Operation;
/**
- * A set that supports a specific operation
- * with other peers.
+ * Detail information about an operation.
*/
-struct Set
+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_Handle *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;
/**
- * Appropriate state for each type of
- * operation.
+ * The type of the operation.
+ */
+ enum GNUNET_SET_OperationType 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;
};
/**
- * Detail information about an operation.
+ * 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, NULL on error
*/
-struct OperationSpecification
+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);
+
+
+typedef struct SetState *
+(*CopyStateImpl) (struct Set *op);
+
+
+/**
+ * Dispatch table for a specific set operation. Every set operation
+ * has to implement the callback in this struct.
+ */
+struct SetVT
{
/**
- * The type of the operation.
+ * Callback for the set creation.
*/
- enum GNUNET_SET_OperationType operation;
+ CreateImpl create;
/**
- * The remove peer we evaluate the operation with
+ * Callback for element insertion
*/
- struct GNUNET_PeerIdentity peer;
+ AddRemoveImpl add;
/**
- * Application ID for the operation, used to distinguish
- * multiple operations of the same type with the same peer.
+ * Callback for element removal.
*/
- struct GNUNET_HashCode app_id;
+ AddRemoveImpl remove;
/**
- * Context message, may be NULL.
+ * Callback for accepting a set operation request
*/
- struct GNUNET_MessageHeader *context_msg;
+ OpAcceptImpl accept;
/**
- * Salt to use for the operation.
+ * Callback for starting evaluation with a remote peer.
*/
- uint32_t salt;
+ OpEvaluateImpl evaluate;
/**
- * ID used to identify responses to a client.
+ * Callback for destruction of the set state.
*/
- uint32_t client_request_id;
+ DestroySetImpl destroy_set;
/**
- * Set associated with the operation, NULL until the spec has been associated
- * with a set.
+ * Callback for handling operation-specific messages.
*/
- struct Set *set;
+ MsgHandlerImpl msg_handler;
+
+ /**
+ * Callback for handling the remote peer's disconnect.
+ */
+ PeerDisconnectImpl peer_disconnect;
+
+ /**
+ * Callback for canceling an operation by its ID.
+ */
+ CancelImpl cancel;
+
+ CopyStateImpl copy_state;
};
/**
- * A listener is inhabited by a client, and
- * waits for evaluation requests from remote peers.
+ * MutationEvent gives information about changes
+ * to an element (removal / addition) in a set content.
*/
-struct Listener
+struct MutationEvent
{
/**
- * Listeners are held in a doubly linked list.
+ * First generation affected by this mutation event.
+ *
+ * If @a generation is 0, this mutation event is a list
+ * sentinel element.
*/
- struct Listener *next;
+ unsigned int generation;
/**
- * Listeners are held in a doubly linked list.
+ * If @a added is #GNUNET_YES, then this is a
+ * `remove` event, otherwise it is an `add` event.
*/
- struct Listener *prev;
+ int added;
+};
+
+/**
+ * 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
+{
/**
- * Client that owns the listener.
- * Only one client may own a listener.
+ * The actual element. The data for the element
+ * should be allocated at the end of this struct.
*/
- struct GNUNET_SERVER_Client *client;
+ struct GNUNET_SET_Element element;
/**
- * Message queue for the client
+ * Hash of the element. For set union: Will be used to derive the
+ * different IBF keys for different salts.
*/
- struct GNUNET_MQ_Handle *client_mq;
+ struct GNUNET_HashCode element_hash;
/**
- * The type of the operation.
+ * If @a mutations is not NULL, it contains
+ * a list of mutations, ordered by increasing generation.
+ * The list is terminated by a sentinel event with `generation`
+ * set to 0.
+ *
+ * If @a mutations is NULL, then this element exists in all generations
+ * of the respective set content this element belongs to.
*/
- enum GNUNET_SET_OperationType operation;
+ struct MutationEvent *mutations;
/**
- * Application ID for the operation, used to distinguish
- * multiple operations of the same type with the same peer.
+ * Number of elements in the array @a mutations.
*/
- struct GNUNET_HashCode app_id;
+ unsigned int mutations_size;
+
+ /**
+ * #GNUNET_YES if the element is a remote element, and does not belong
+ * to the operation's set.
+ */
+ int remote;
};
-/**
- * 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.
- */
-struct Incoming;
+struct Listener;
/**
- * Different types a tunnel can be.
+ * Operation context used to execute a set operation.
*/
-enum TunnelContextType {
+struct Operation
+{
+ /**
+ * V-Table for the operation belonging to the tunnel contest.
+ *
+ * Used for all operation specific operations after receiving the ops request
+ */
+ const struct SetVT *vt;
+
+ /**
+ * Channel to the peer.
+ */
+ struct GNUNET_CADET_Channel *channel;
+
+ /**
+ * Port this operation runs on.
+ */
+ struct Listener *listener;
+
+ /**
+ * Message queue for the channel.
+ */
+ 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.
+ */
+ struct GNUNET_SCHEDULER_Task *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;
+
/**
- * Tunnel is waiting for a set request from the tunnel,
- * or for the ack/nack of the client for a received request.
+ * #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.
*/
- CONTEXT_INCOMING,
+ int is_incoming;
/**
- * The tunnel performs a union operation.
+ * Generation in which the operation handle
+ * was created.
*/
- CONTEXT_OPERATION_UNION,
+ unsigned int generation_created;
/**
- * The tunnel performs an intersection operation.
+ * Incremented whenever (during shutdown) some component still
+ * needs to do something with this before the operation is freed.
+ * (Used as a reference counter, but only during termination.)
*/
- CONTEXT_OPERATION_INTERSECTION,
+ unsigned int keep;
};
/**
- * State associated with the tunnel, dependent on
- * tunnel type.
+ * SetContent stores the actual set elements,
+ * which may be shared by multiple generations derived
+ * from one set.
*/
-union TunnelContextData
+struct SetContent
{
/**
- * Valid for tag 'CONTEXT_INCOMING'
+ * Number of references to the content.
+ */
+ unsigned int refcount;
+
+ /**
+ * Maps `struct GNUNET_HashCode *` to `struct ElementEntry *`.
+ */
+ struct GNUNET_CONTAINER_MultiHashMap *elements;
+
+ unsigned int latest_generation;
+
+ /**
+ * Mutations requested by the client that we're
+ * unable to execute right now because we're iterating
+ * over the underlying hash map of elements.
*/
- struct Incoming *incoming;
+ struct PendingMutation *pending_mutations_head;
/**
- * Valid for tag 'CONTEXT_OPERATION_UNION'
+ * Mutations requested by the client that we're
+ * unable to execute right now because we're iterating
+ * over the underlying hash map of elements.
*/
- struct UnionEvaluateOperation *union_op;
+ struct PendingMutation *pending_mutations_tail;
/**
- * Valid for tag 'CONTEXT_OPERATION_INTERSECTION'
+ * Number of concurrently active iterators.
*/
- struct IntersectionEvaluateOperation *intersection_op;
+ int iterator_count;
};
-/**
- * Information about a tunnel we are connected to.
- * Used as tunnel context with mesh.
- */
-struct TunnelContext
+
+struct GenerationRange
{
/**
- * Type of the tunnel.
+ * First generation that is excluded.
*/
- enum TunnelContextType type;
+ unsigned int start;
/**
- * State associated with the tunnel, dependent on
- * tunnel type.
+ * Generation after the last excluded generation.
*/
- union TunnelContextData data;
+ unsigned int end;
};
+struct PendingMutation
+{
+ struct PendingMutation *prev;
+ struct PendingMutation *next;
-/**
- * Configuration of the local peer
- */
-extern const struct GNUNET_CONFIGURATION_Handle *configuration;
+ struct Set *set;
-extern struct GNUNET_MESH_Handle *mesh;
+ /**
+ * Message that describes the desired mutation.
+ * May only be a GNUNET_MESSAGE_TYPE_SET_ADD or
+ * GNUNET_MESSAGE_TYPE_SET_REMOVE.
+ */
+ struct GNUNET_MessageHeader *mutation_message;
+};
/**
- * Create a new set supporting the union operation
- *
- * @return the newly created set
+ * A set that supports a specific operation with other peers.
*/
-struct Set *
-_GSS_union_set_create (void);
+struct Set
+{
+ /**
+ * Sets are held in a doubly linked list (in `sets_head` and `sets_tail`).
+ */
+ struct Set *next;
-/**
- * Evaluate a union operation with
- * a remote peer.
- *
- * @param spec specification of the operation the evaluate
- * @param tunnel tunnel already connected to the partner peer
- * @param set the set to evaluate the operation with
- * @return a handle to the operation
- */
-struct UnionEvaluateOperation *
-_GSS_union_evaluate (struct OperationSpecification *spec,
- struct GNUNET_MESH_Tunnel *tunnel);
+ /**
+ * 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;
-/**
- * Add the element from the given element message to the set.
- *
- * @param m message with the element
- * @param set set to add the element to
- */
-void
-_GSS_union_add (struct GNUNET_SET_ElementMessage *m, struct Set *set);
+ /**
+ * 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;
-/**
- * Remove the element given in the element message from the set.
- * Only marks the element as removed, so that older set operations can still exchange it.
- *
- * @param m message with the element
- * @param set set to remove the element from
- */
-void
-_GSS_union_remove (struct GNUNET_SET_ElementMessage *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;
+
+ /**
+ * Evaluate operations are held in a linked list.
+ */
+ struct Operation *ops_head;
+
+ /**
+ * Evaluate operations are held in a linked list.
+ */
+ struct Operation *ops_tail;
+
+ /**
+ * Current generation, that is, number of previously executed
+ * operations and lazy copies on the underlying set content.
+ */
+ unsigned int current_generation;
+
+ /**
+ * List of generations we have to exclude, due to lazy copies.
+ */
+ struct GenerationRange *excluded_generations;
+
+ /**
+ * Number of elements in array @a excluded_generations.
+ */
+ unsigned int excluded_generations_size;
+
+ /**
+ * 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;
+
+ /**
+ * Generation we're currently iteration over.
+ */
+ unsigned int iter_generation;
+
+ /**
+ * Content, possibly shared by multiple sets,
+ * and thus reference counted.
+ */
+ struct SetContent *content;
+};
+
+
+extern struct GNUNET_STATISTICS_Handle *_GSS_statistics;
/**
- * Destroy a set that supports the union operation
+ * 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 set the set to destroy, must be of type GNUNET_SET_OPERATION_UNION
+ * @param op operation to destroy
+ * @param gc #GNUNET_YES to perform garbage collection on the set
*/
void
-_GSS_union_set_destroy (struct Set *set);
+_GSS_operation_destroy (struct Operation *op,
+ int gc);
/**
- * Accept an union operation request from a remote peer
+ * Get the table with implementing functions for set union.
*
- * @param spec all necessary information about the operation
- * @param tunnel open tunnel to the partner's peer
- * @return operation
+ * @return the operation specific VTable
*/
-struct UnionEvaluateOperation *
-_GSS_union_accept (struct OperationSpecification *spec,
- struct GNUNET_MESH_Tunnel *tunnel);
+const struct SetVT *
+_GSS_union_vt (void);
/**
- * Destroy a union operation, and free all resources
- * associated with it.
+ * Get the table with implementing functions for set intersection.
*
- * @param eo the union operation to destroy
+ * @return the operation specific VTable
*/
-void
-_GSS_union_operation_destroy (struct UnionEvaluateOperation *eo);
+const struct SetVT *
+_GSS_intersection_vt (void);
-/**
- * Dispatch messages for a union operation.
- *
- * @param cls closure
- * @param tunnel mesh tunnel
- * @param tunnel_ctx tunnel context
- * @param mh message to process
- * @return ???
- */
int
-_GSS_union_handle_p2p_message (void *cls,
- struct GNUNET_MESH_Tunnel *tunnel,
- void **tunnel_ctx,
- const struct GNUNET_MessageHeader *mh);
+_GSS_is_element_of_set (struct ElementEntry *ee,
+ struct Set *set);
+
+int
+_GSS_is_element_of_operation (struct ElementEntry *ee,
+ struct Operation *op);
#endif