Boston, MA 02111-1307, USA.
*/
-/**
+/**
* @file include/gnunet_multicast_service.h
* @brief multicast service; establish tunnels to distant peers
* @author Christian Grothoff
#include "gnunet_util_lib.h"
#include "gnunet_transport_service.h"
-/**
+/**
* Version number of GNUnet-multicast API.
*/
#define GNUNET_MULTICAST_VERSION 0x00000000
+/**
+ * Maximum size of a multicast message fragment.
+ */
+#define GNUNET_MULTICAST_FRAGMENT_MAX_SIZE 63 * 1024
-/**
+/**
* Opaque handle for a multicast group member.
*/
struct GNUNET_MULTICAST_Member;
-/**
+/**
* Handle for the origin of a multicast group.
*/
struct GNUNET_MULTICAST_Origin;
*/
GNUNET_MULTICAST_MESSAGE_LAST_FRAGMENT = 1 << 1,
- /**
+ /**
* OR'ed flags if message is not fragmented.
*/
GNUNET_MULTICAST_MESSAGE_NOT_FRAGMENTED
GNUNET_NETWORK_STRUCT_BEGIN
-/**
+/**
* Header of a multicast message fragment.
*
* This format is public as the replay mechanism must replay message fragments using the
struct GNUNET_MULTICAST_MessageHeader
{
- /**
+ /**
* Header for all multicast message fragments from the origin.
*/
struct GNUNET_MessageHeader header;
- /**
+ /**
* Number of hops this message fragment has taken since the origin.
*
* Helpful to determine shortest paths to the origin among honest peers for
*/
uint32_t hop_counter GNUNET_PACKED;
- /**
+ /**
* ECC signature of the message fragment.
*
* Signature must match the public key of the multicast group.
*/
- struct GNUNET_CRYPTO_EccSignature signature;
+ struct GNUNET_CRYPTO_EddsaSignature signature;
- /**
+ /**
* Purpose for the signature and size of the signed data.
*/
struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
- /**
+ /**
* Number of the message fragment, monotonically increasing.
*/
uint64_t fragment_id GNUNET_PACKED;
- /**
+ /**
* Byte offset of this @e fragment of the @e message.
*/
uint64_t fragment_offset GNUNET_PACKED;
- /**
+ /**
* Number of the message this fragment belongs to.
*
* Set in GNUNET_MULTICAST_origin_to_all().
*/
uint64_t message_id GNUNET_PACKED;
- /**
+ /**
* Counter that monotonically increases whenever a member parts the group.
*
* Set in GNUNET_MULTICAST_origin_to_all().
/**
* Flags for this message fragment.
*/
- enum GNUNET_MULTICAST_MessageFlags flags GNUNET_PACKED;
+ uint32_t flags GNUNET_PACKED;
/* Followed by message body. */
};
GNUNET_NETWORK_STRUCT_END
-GNUNET_NETWORK_STRUCT_BEGIN
-
-/**
- * Header of a request from a member to the origin.
- *
- * FIXME: this struct is going to be internal.
- */
-struct GNUNET_MULTICAST_RequestHeader
-{
- /**
- * Header for all requests from a member to the origin.
- */
- struct GNUNET_MessageHeader header;
-
- /**
- * Public key of the sending member.
- */
- struct GNUNET_CRYPTO_EccPublicKey member_key;
-
- /**
- * ECC signature of the request fragment.
- *
- * Signature must match the public key of the multicast group.
- */
- struct GNUNET_CRYPTO_EccSignature signature;
-
- /**
- * Purpose for the signature and size of the signed data.
- */
- struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
-
- /**
- * Number of the request fragment, monotonically increasing.
- */
- uint64_t fragment_id GNUNET_PACKED;
-
- /**
- * Byte offset of this @e fragment of the @e request.
- */
- uint64_t fragment_offset GNUNET_PACKED;
-
- /**
- * Number of the request this fragment belongs to.
- *
- * Set in GNUNET_MULTICAST_origin_to_all().
- */
- uint64_t request_id GNUNET_PACKED;
-
- /**
- * Flags for this request.
- */
- enum GNUNET_MULTICAST_MessageFlags flags GNUNET_PACKED;
-
- /* Followed by request body. */
-};
-
-GNUNET_NETWORK_STRUCT_END
-
-
-GNUNET_NETWORK_STRUCT_BEGIN
-
-/**
- * Header of a join request sent to the origin or another member.
- *
- * FIXME: this struct is going to be internal.
- */
-struct GNUNET_MULTICAST_JoinRequest {
- /**
- * Header for the join request.
- */
- struct GNUNET_MessageHeader header;
-
- /**
- * ECC signature of the rest of the fields of the join request.
- *
- * Signature must match the public key of the joining member.
- */
- struct GNUNET_CRYPTO_EccSignature signature;
-
- /**
- * Purpose for the signature and size of the signed data.
- */
- struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
-
- /**
- * Public key of the target group.
- */
- struct GNUNET_CRYPTO_EccPublicKey group_key;
-
- /**
- * Public key of the joining member.
- */
- struct GNUNET_CRYPTO_EccPublicKey member_key;
-
- /**
- * Peer identity of the joining member.
- */
- struct GNUNET_PeerIdentity member_peer;
-
- /* Followed by request body. */
-};
-
-GNUNET_NETWORK_STRUCT_END
-
-/**
+/**
* Handle that identifies a join request.
*
* Used to match calls to #GNUNET_MULTICAST_JoinCallback to the
- * corresponding calls to GNUNET_MULTICAST_join_decision().
+ * corresponding calls to #GNUNET_MULTICAST_join_decision().
*/
struct GNUNET_MULTICAST_JoinHandle;
-/**
+/**
* Function to call with the decision made for a join request.
*
* Must be called once and only once in response to an invocation of the
* @param jh Join request handle.
* @param is_admitted #GNUNET_YES if joining is approved,
* #GNUNET_NO if it is disapproved
- * @param admitted_since Message ID the member is admitted since.
* @param relay_count Number of relays given.
* @param relays Array of suggested peers that might be useful relays to use
* when joining the multicast group (essentially a list of peers that
* application layer; this response is to be transmitted to the
* peer that issued the request even if admission is denied.
*/
-void
+struct GNUNET_MULTICAST_ReplayHandle *
GNUNET_MULTICAST_join_decision (struct GNUNET_MULTICAST_JoinHandle *jh,
int is_admitted,
- uint64_t admitted_since,
unsigned int relay_count,
const struct GNUNET_PeerIdentity *relays,
const struct GNUNET_MessageHeader *join_response);
-/**
+/**
* Method called whenever another peer wants to join the multicast group.
*
* Implementations of this function must call GNUNET_MULTICAST_join_decision()
*/
typedef void
(*GNUNET_MULTICAST_JoinCallback) (void *cls,
- const struct GNUNET_EccPublicKey *member_key,
+ const struct GNUNET_CRYPTO_EddsaPublicKey *member_key,
const struct GNUNET_MessageHeader *join_req,
struct GNUNET_MULTICAST_JoinHandle *jh);
-/**
+/**
* Handle to pass back for the answer of a membership test.
*/
struct GNUNET_MULTICAST_MembershipTestHandle;
-/**
+/**
* Call informing multicast about the decision taken for a membership test.
*
* @param mth Handle that was given for the query.
int result);
-/**
+/**
* Method called to test if a member was in the group at a particular time.
*
* It is called when a replay request is received to determine if the requested
*/
typedef void
(*GNUNET_MULTICAST_MembershipTestCallback) (void *cls,
- const struct GNUNET_CRYPTO_EccPublicKey *member_key,
+ const struct GNUNET_CRYPTO_EddsaPublicKey *member_key,
uint64_t message_id,
uint64_t group_generation,
struct GNUNET_MULTICAST_MembershipTestHandle *mth);
-/**
+/**
* Function called whenever a group member has transmitted a request
* to the origin (other than joining or leaving).
*
+ * FIXME: need to distinguish between origin cancelling a message (some fragments
+ * were sent, then the rest 'discarded') and the case where we got disconnected;
+ * right now, both would mean 'msg' is NULL, but they could be quite different...
+ * So the semantics from the receiver side of
+ * GNUNET_MULTICAST_member_to_origin_cancel() are not clear here. Maybe we
+ * should do something with the flags in this case?
+ *
* @param cls Closure (set from GNUNET_MULTICAST_origin_start).
* @param sender Identity of the sender.
* @param req Request to the origin.
*/
typedef void
(*GNUNET_MULTICAST_RequestCallback) (void *cls,
- const struct GNUNET_EccPublicKey *member_key,
+ const struct GNUNET_CRYPTO_EddsaPublicKey *member_key,
const struct GNUNET_MessageHeader *req,
enum GNUNET_MULTICAST_MessageFlags flags);
-/**
+/**
* Function called whenever a group member is receiving a message fragment from
* the origin.
*
* response of the @e origin (as given to GNUNET_MULTICAST_join_decision()) and
* then a second time with NULL to indicate that the connection failed for good.
*
+ * FIXME: need to distinguish between origin cancelling a message (some fragments
+ * were sent, then the rest 'discarded') and the case where we got disconnected;
+ * right now, both would mean 'msg' is NULL, but they could be quite different...
+ * So the semantics from the receiver side of
+ * GNUNET_MULTICAST_origin_to_all_cancel() are not clear here.
+ *
* @param cls Closure (set from GNUNET_MULTICAST_member_join())
* @param msg Message from the origin, NULL if the origin shut down
* (or we were kicked out, and we should thus call
const struct GNUNET_MessageHeader *msg);
-/**
+/**
* Function called with the result of an asynchronous operation.
*
* @see GNUNET_MULTICAST_replay_fragment()
- *
+ *
* @param result Result of the operation.
*/
typedef void
int result);
-/**
+/**
* Opaque handle to a replay request from the multicast service.
*/
struct GNUNET_MULTICAST_ReplayHandle;
-/**
+/**
* Functions with this signature are called whenever the multicast service needs
- * a message to be replayed.
+ * a message fragment to be replayed by fragment_id.
*
* Implementations of this function MUST call GNUNET_MULTICAST_replay() ONCE
* (with a message or an error); however, if the origin is destroyed or the
*/
typedef void
(*GNUNET_MULTICAST_ReplayFragmentCallback) (void *cls,
- const struct GNUNET_CRYPTO_EccPublicKey *member_key,
+ const struct GNUNET_CRYPTO_EddsaPublicKey *member_key,
uint64_t fragment_id,
uint64_t flags,
struct GNUNET_MULTICAST_ReplayHandle *rh);
-/**
+/**
* Functions with this signature are called whenever the multicast service needs
- * a message to be replayed.
+ * a message fragment to be replayed by message_id and fragment_offset.
*
* Implementations of this function MUST call GNUNET_MULTICAST_replay() ONCE
* (with a message or an error); however, if the origin is destroyed or the
*/
typedef void
(*GNUNET_MULTICAST_ReplayMessageCallback) (void *cls,
- const struct GNUNET_CRYPTO_EccPublicKey *member_key,
+ const struct GNUNET_CRYPTO_EddsaPublicKey *member_key,
uint64_t message_id,
uint64_t fragment_offset,
uint64_t flags,
struct GNUNET_MULTICAST_ReplayHandle *rh);
-/**
+/**
* Possible error codes during replay.
*/
enum GNUNET_MULTICAST_ReplayErrorCode
{
- /**
+ /**
* Everything is fine.
*/
GNUNET_MULTICAST_REC_OK = 0,
- /**
+ /**
* Message fragment not found in the message store.
*
* Either discarded if it is too old, or not arrived yet if this member has
*/
GNUNET_MULTICAST_REC_NOT_FOUND = 1,
- /**
+ /**
* Fragment ID counter was larger than the highest counter this
* replay function has ever encountered; thus it is likely the
* origin never sent it and we're at the HEAD of the multicast
*/
GNUNET_MULTICAST_REC_PAST_HEAD = 2,
- /**
+ /**
* Access is denied to the requested fragment, membership test did not pass.
*/
GNUNET_MULTICAST_REC_ACCESS_DENIED = 3,
- /**
+ /**
* Internal error (i.e. database error). Try some other peer.
*/
GNUNET_MULTICAST_REC_INTERNAL_ERROR = 4
};
-/**
+/**
* Replay a message fragment for the multicast group.
*
* @param rh Replay handle identifying which replay operation was requested.
* @param ec Error code.
*/
void
-GNUNET_MULTICAST_replay (struct GNUNET_MULTICAST_ReplayHandle *rh,
- const struct GNUNET_MessageHeader *msg,
- enum GNUNET_MULTICAST_ReplayErrorCode ec);
+GNUNET_MULTICAST_replay_response (struct GNUNET_MULTICAST_ReplayHandle *rh,
+ const struct GNUNET_MessageHeader *msg,
+ enum GNUNET_MULTICAST_ReplayErrorCode ec);
+
+
+/**
+ * Indicate the end of the replay session.
+ *
+ * Invalidates the replay handle.
+ *
+ * @param rh Replay session to end.
+ */
+void
+GNUNET_MULTICAST_replay_response_end (struct GNUNET_MULTICAST_ReplayHandle *rh);
+
/**
* Function called to provide data for a transmission for a replay.
* @see GNUNET_MULTICAST_replay2()
*/
typedef int
-(*GNUNET_MULTICAST_ReplayTransmitNotify)(void *cls,
- size_t *data_size,
- void *data);
+(*GNUNET_MULTICAST_ReplayTransmitNotify) (void *cls,
+ size_t *data_size,
+ void *data);
+
-/**
+/**
* Replay a message for the multicast group.
*
* @param rh Replay handle identifying which replay operation was requested.
* @param notify_cls Closure for @a notify.
*/
void
-GNUNET_MULTICAST_replay2 (struct GNUNET_MULTICAST_ReplayHandle *rh,
- GNUNET_MULTICAST_ReplayTransmitNotify notify,
- void *notify_cls);
+GNUNET_MULTICAST_replay_response2 (struct GNUNET_MULTICAST_ReplayHandle *rh,
+ GNUNET_MULTICAST_ReplayTransmitNotify notify,
+ void *notify_cls);
-/**
+/**
* Start a multicast group.
*
* Will advertise the origin in the P2P overlay network under the respective
* @param cfg Configuration to use.
* @param priv_key ECC key that will be used to sign messages for this
* multicast session; public key is used to identify the multicast group;
- * FIXME: we'll likely want to use NOT the p521 curve here, but a cheaper
- * one in the future.
- * @param last_fragment_id Last fragment ID to continue counting fragments from
- * when restarting the origin. 0 for a new group.
+ * @param next_fragment_id Next fragment ID to continue counting fragments from
+ * when restarting the origin. 1 for a new group.
* @param join_cb Function called to approve / disapprove joining of a peer.
- * @param test_cb Function multicast can use to test group membership.
- * @param replay_cb Function that can be called to replay a message.
+ * @param mem_test_cb Function multicast can use to test group membership.
+ * @param replay_frag_cb Function that can be called to replay a message fragment.
+ * @param replay_msg_cb Function that can be called to replay a message.
* @param request_cb Function called with message fragments from group members.
* @param message_cb Function called with the message fragments sent to the
* network by GNUNET_MULTICAST_origin_to_all(). These message fragments
*/
struct GNUNET_MULTICAST_Origin *
GNUNET_MULTICAST_origin_start (const struct GNUNET_CONFIGURATION_Handle *cfg,
- const struct GNUNET_CRYPTO_EccPrivateKey *priv_key,
- uint64_t last_fragment_id,
+ const struct GNUNET_CRYPTO_EddsaPrivateKey *priv_key,
+ uint64_t next_fragment_id,
GNUNET_MULTICAST_JoinCallback join_cb,
- GNUNET_MULITCAST_MembershipTestCallback test_cb,
- GNUNET_MULITCAST_ReplayCallback replay_cb,
+ GNUNET_MULTICAST_MembershipTestCallback mem_test_cb,
+ GNUNET_MULTICAST_ReplayFragmentCallback replay_frag_cb,
+ GNUNET_MULTICAST_ReplayMessageCallback replay_msg_cb,
GNUNET_MULTICAST_RequestCallback request_cb,
GNUNET_MULTICAST_MessageCallback message_cb,
void *cls);
/**
- * Function called to provide data for a transmission from the origin to all members.
+ * Function called to provide data for a transmission from the origin to all
+ * members.
+ *
+ * Note that returning #GNUNET_OK or #GNUNET_SYSERR (but not #GNUNET_NO)
+ * invalidates the respective transmission handle.
+ *
+ * @param cls Closure.
+ * @param[in,out] data_size Initially set to the number of bytes available in
+ * @a data, should be set to the number of bytes written to data.
+ * @param[out] data Where to write the body of the message to give to the
+ * method. The function must copy at most @a data_size bytes to @a data.
+ * @return #GNUNET_SYSERR on error (fatal, aborts transmission)
+ * #GNUNET_NO on success, if more data is to be transmitted later.
+ * Should be used if @a data_size was not big enough to take all the
+ * data. If 0 is returned in @a data_size the transmission is paused,
+ * and can be resumed with GNUNET_MULTICAST_origin_to_all_resume().
+ * #GNUNET_YES if this completes the transmission (all data supplied)
*/
typedef int
-(*GNUNET_MULTICAST_OriginTransmitNotify)(void *cls,
- size_t *data_size,
- void *data);
+(*GNUNET_MULTICAST_OriginTransmitNotify) (void *cls,
+ size_t *data_size,
+ void *data);
-/**
+/**
* Handle for a request to send a message to all multicast group members
* (from the origin).
*/
struct GNUNET_MULTICAST_OriginMessageHandle;
-/**
+/**
* Send a message to the multicast group.
*
* @param origin Handle to the multicast group.
* @param message_id Application layer ID for the message. Opaque to multicast.
* @param group_generation Group generation of the message. Documented in
* GNUNET_MULTICAST_MessageHeader.
- * @param size Number of bytes to transmit.
- * FIXME: Needed? The end of the message can be flagged with a last fragment flag.
* @param notify Function to call to get the message.
* @param notify_cls Closure for @a notify.
* @return NULL on error (i.e. request already pending).
GNUNET_MULTICAST_origin_to_all (struct GNUNET_MULTICAST_Origin *origin,
uint64_t message_id,
uint64_t group_generation,
- size_t size,
GNUNET_MULTICAST_OriginTransmitNotify notify,
void *notify_cls);
-/**
+
+/**
+ * Resume message transmission to multicast group.
+ *
+ * @param mh Request to cancel.
+ */
+void
+GNUNET_MULTICAST_origin_to_all_resume (struct GNUNET_MULTICAST_OriginMessageHandle *mh);
+
+
+/**
* Cancel request for message transmission to multicast group.
*
* @param mh Request to cancel.
GNUNET_MULTICAST_origin_to_all_cancel (struct GNUNET_MULTICAST_OriginMessageHandle *mh);
-/**
+/**
* Stop a multicast group.
*
* @param origin Multicast group to stop.
GNUNET_MULTICAST_origin_stop (struct GNUNET_MULTICAST_Origin *origin);
-/**
+/**
* Join a multicast group.
*
* The entity joining is always the local peer. Further information about the
* @a message_cb is invoked with a (failure) response and then with NULL. If
* the join succeeds, outstanding (state) messages and ongoing multicast
* messages will be given to the @a message_cb until the member decides to part
- * the group. The @a test_cb and @a replay_cb functions may be called at
+ * the group. The @a mem_test_cb and @a replay_cb functions may be called at
* anytime by the multicast service to support relaying messages to other
* members of the group.
*
* @a relay (might, for example, contain a user, bind user
* identity/pseudonym to peer identity, application-level message to
* origin, etc.).
- * @param max_known_fragment_id Largest known message fragment ID to the replay
- * service; all messages with IDs larger than this ID will be replayed if
- * possible (lower IDs will be considered known and thus only
- * be replayed upon explicit request).
- * FIXME: needed? can be optional or moved to a separate function.
* @param join_cb Function called to approve / disapprove joining of a peer.
- * @param test_cb Function multicast can use to test group membership.
- * @param replay_cb Function that can be called to replay messages
- * this peer already knows from this group; NULL if this
+ * @param mem_test_cb Function multicast can use to test group membership.
+ * @param replay_frag_cb Function that can be called to replay message fragments
+ * this peer already knows from this group. NULL if this
+ * client is unable to support replay.
+ * @param replay_msg_cb Function that can be called to replay message fragments
+ * this peer already knows from this group. NULL if this
* client is unable to support replay.
* @param message_cb Function to be called for all message fragments we
* receive from the group, excluding those our @a replay_cb
*/
struct GNUNET_MULTICAST_Member *
GNUNET_MULTICAST_member_join (const struct GNUNET_CONFIGURATION_Handle *cfg,
- const struct GNUNET_CRYPTO_EccPublicKey *group_key,
- const struct GNUNET_CRYPTO_EccPrivateKey *member_key,
+ const struct GNUNET_CRYPTO_EddsaPublicKey *group_key,
+ const struct GNUNET_CRYPTO_EddsaPrivateKey *member_key,
const struct GNUNET_PeerIdentity *origin,
- size_t relay_count,
+ uint32_t relay_count,
const struct GNUNET_PeerIdentity *relays,
const struct GNUNET_MessageHeader *join_request,
- uint64_t max_known_fragment_id,
GNUNET_MULTICAST_JoinCallback join_cb,
- GNUNET_MULITCAST_MembershipTestCallback test_cb,
- GNUNET_MULITCAST_ReplayCallback replay_cb,
+ GNUNET_MULTICAST_MembershipTestCallback mem_test_cb,
+ GNUNET_MULTICAST_ReplayFragmentCallback replay_frag_cb,
+ GNUNET_MULTICAST_ReplayMessageCallback replay_msg_cb,
GNUNET_MULTICAST_MessageCallback message_cb,
void *cls);
-
-/**
+/**
* Handle for a replay request.
*/
struct GNUNET_MULTICAST_MemberReplayHandle;
-/**
+/**
* Request a fragment to be replayed by fragment ID.
*
* Useful if messages below the @e max_known_fragment_id given when joining are
* @param member Membership handle.
* @param fragment_id ID of a message fragment that this client would like to
see replayed.
- * @param flags Additional flags for the replay request. It is used & defined
- * by the replay callback.
- * @param message_cb Function to be called for the replayed message.
- * @param message_cb_cls Closure for @a message_cb.
+ * @param flags Additional flags for the replay request. It is used and defined
+ * by the replay callback. FIXME: which replay callback? FIXME: use enum?
+ * FIXME: why not pass reply cb here?
* @return Replay request handle, NULL on error.
*/
struct GNUNET_MULTICAST_MemberReplayHandle *
GNUNET_MULTICAST_member_replay_fragment (struct GNUNET_MULTICAST_Member *member,
uint64_t fragment_id,
- uint64_t flags)
+ uint64_t flags);
-/**
+
+/**
* Request a message fr to be replayed.
*
* Useful if messages below the @e max_known_fragment_id given when joining are
* needed and not known to the client.
*
* @param member Membership handle.
- * @param fragment_id ID of a message fragment that this client would like to
- see replayed.
- * @param message_id ID of a message that this client would like to see
- * replayed. Typically only one of the @a fragment_id and @a message_id
- * is given. Specifying a @a message_id would return the last fragment
- * of the message, which allows requesting the preceding fragments of the
- * message by looking at the @e fragment_delta header field.
+ * @param message_id ID of the message this client would like to see replayed.
+ * @param fragment_offset Offset of the fragment within the message to replay.
* @param flags Additional flags for the replay request. It is used & defined
- * by the replay callback. E.g. the PSYC service would use this to
- * implement state synchronization.
+ * by the replay callback.
* @param result_cb Function to be called for the replayed message.
- * @param result_cb_cls Closure for @a message_cb.
+ * @param result_cb_cls Closure for @a result_cb.
* @return Replay request handle, NULL on error.
*/
struct GNUNET_MULTICAST_MemberReplayHandle *
void *result_cb_cls);
-/**
+/**
* Cancel a replay request.
*
* @param rh Request to cancel.
GNUNET_MULTICAST_member_replay_cancel (struct GNUNET_MULTICAST_MemberReplayHandle *rh);
-/**
+/**
* Part a multicast group.
*
* Disconnects from all group members and invalidates the @a member handle.
*
* An application-dependent part message can be transmitted beforehand using
- * GNUNET_MULTICAST_member_to_origin())
+ * #GNUNET_MULTICAST_member_to_origin())
*
* @param member Membership handle.
*/
/**
* Function called to provide data for a transmission from a member to the origin.
+ *
+ * Note that returning #GNUNET_OK or #GNUNET_SYSERR (but not #GNUNET_NO)
+ * invalidates the respective transmission handle.
+ *
+ * @param cls Closure.
+ * @param[in,out] data_size Initially set to the number of bytes available in
+ * @a data, should be set to the number of bytes written to data.
+ * @param[out] data Where to write the body of the message to give to the
+ * method. The function must copy at most @a data_size bytes to @a data.
+ * @return #GNUNET_SYSERR on error (fatal, aborts transmission)
+ * #GNUNET_NO on success, if more data is to be transmitted later.
+ * Should be used if @a data_size was not big enough to take all the
+ * data. If 0 is returned in @a data_size the transmission is paused,
+ * and can be resumed with GNUNET_MULTICAST_member_to_origin_resume().
+ * #GNUNET_YES if this completes the transmission (all data supplied)
*/
typedef int
-(*GNUNET_MULTICAST_MemberTransmitNotify)(void *cls,
- size_t *data_size,
- void *data);
+(*GNUNET_MULTICAST_MemberTransmitNotify) (void *cls,
+ size_t *data_size,
+ void *data);
-/**
+/**
* Handle for a message to be delivered from a member to the origin.
*/
struct GNUNET_MULTICAST_MemberRequestHandle;
-/**
+/**
* Send a message to the origin of the multicast group.
- *
+ *
* @param member Membership handle.
* @param message_id Application layer ID for the message. Opaque to multicast.
- * @param size Number of bytes we want to send to origin.
* @param notify Callback to call to get the message.
* @param notify_cls Closure for @a notify.
* @return Handle to cancel request, NULL on error (i.e. request already pending).
struct GNUNET_MULTICAST_MemberRequestHandle *
GNUNET_MULTICAST_member_to_origin (struct GNUNET_MULTICAST_Member *member,
uint64_t message_id,
- size_t size,
GNUNET_MULTICAST_MemberTransmitNotify notify,
void *notify_cls);
-/**
+/**
+ * Resume message transmission to origin.
+ *
+ * @param rh Request to cancel.
+ */
+void
+GNUNET_MULTICAST_member_to_origin_resume (struct GNUNET_MULTICAST_MemberRequestHandle *rh);
+
+
+/**
* Cancel request for message transmission to origin.
*
* @param rh Request to cancel.