/*
This file is part of GNUnet.
- (C) 2012, 2013 Christian Grothoff (and other contributing authors)
+ Copyright (C) 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
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 include/gnunet_psyc_service.h
- * @brief psyc service; high-level access to the PSYC protocol
+ * @brief PSYC service; high-level access to the PSYC protocol
* note that clients of this API are NOT expected to
* understand the PSYC message format, only the semantics!
+ * Parsing (and serializing) the PSYC stream format is done
+ * within the implementation of the libgnunetpsyc library,
+ * and this API deliberately exposes as little as possible
+ * of the actual data stream format to the application!
* @author Christian Grothoff
+ * @author Gabor X Toth
*
- * TODO:
- * - how to deal with very large channel state (i.e. channel
- * containing a movie); this might relate to the question
- * of how (when/etc.) we replay method calls; is only the
- * channel state persistent? What about a 'bounded'
- * channel history, how would we enable that?
- * - how to deal with seeking in large channel state (i.e.
- * skip to minute 45 in movie)
- * - need to change send operations to 'notify_transmit_ready'-style;
- * deal better with 'streaming' arguments while we're at it
+ * NOTE:
+ * - this API does not know about psyc's "root" and "places";
+ * there is no 'root' in GNUnet-Psyc as we're decentralized;
+ * 'places' and 'persons' are combined within the same
+ * abstraction, that of a "channel". Channels are identified
+ * and accessed in this API using a public/private key.
+ * Higher-level applications should use NAMES within GNS
+ * to obtain public keys, and the distinction between
+ * 'places' and 'persons' can then be made with the help
+ * of the naming system (and/or conventions).
+ * Channels are (as in PSYC) organized into a hierarchy; each
+ * channel master (the one with the private key) is then
+ * the operator of the multicast group (its Origin in
+ * the terminology of the multicast API).
+ * - The API supports passing large amounts of data using
+ * 'streaming' for the argument passed to a method. State
+ * and variables must fit into memory and cannot be streamed
+ * (thus, no passing of 4 GB of data in a variable;
+ * once we implement this, we might want to create a
+ * @c \#define for the maximum size of a variable).
+ * - PSYC defines standard variables, methods, etc. This
+ * library deliberately abstracts over all of these; a
+ * higher-level API should combine the naming system (GNS)
+ * and standard methods (message, join, part, warn,
+ * fail, error) and variables (action, color, time,
+ * tag, etc.). However, this API does take over the
+ * routing variables, specifically 'context' (channel),
+ * and 'source'. We only kind-of support 'target', as
+ * the target is either everyone in the group or the
+ * origin, and never just a single member of the group;
+ * for such individual messages, an application needs to
+ * construct an 'inbox' channel where the master (only)
+ * receives messages (but never forwards; private responses
+ * would be transmitted by joining the senders 'inbox'
+ * channel -- or a inbox#bob subchannel). The
+ * goal for all of this is to keep the abstractions in this
+ * API minimal: interaction with multicast, try \& slice,
+ * state/variable/channel management. Higher-level
+ * operations belong elsewhere (so maybe this API should
+ * be called 'PSYC-low', whereas a higher-level API
+ * implementing defaults for standard methods and
+ * variables might be called 'PSYC-std' or 'PSYC-high'.
*/
#ifndef GNUNET_PSYC_SERVICE_H
#endif
#include "gnunet_util_lib.h"
+#include "gnunet_env_lib.h"
#include "gnunet_multicast_service.h"
-
+//Mingw work around
+#ifdef MINGW
+ # ifndef UINT64_MAX
+ # define UINT64_MAX 0xffffffffffffffffULL
+ # endif
+#endif
/**
* Version number of GNUnet-PSYC API.
/**
- * Bits describing special properties of arguments.
+ * Policy flags for a channel.
*/
-enum GNUNET_PSYC_ArgumentFlags
+enum GNUNET_PSYC_ChannelFlags
{
/**
- * Argument is fixed size.
+ * Admission must be confirmed by the master.
*/
- GNUNET_PSYC_AF_FIXED_SIZE = 0,
+ GNUNET_PSYC_CHANNEL_ADMISSION_CONTROL = 1 << 0,
/**
- * Argument is variable-length
+ * Past messages are only available to slaves who were admitted at the time
+ * they were sent to the channel.
*/
- GNUNET_PSYC_AF_VARIABLE_SIZE = 1,
+ GNUNET_PSYC_CHANNEL_RESTRICTED_HISTORY = 1 << 1
+};
+
+/**
+ * PSYC channel policies.
+ */
+enum GNUNET_PSYC_Policy
+{
/**
- * Argument may be supplied incrementally to the callback
+ * Anyone can join the channel, without announcing his presence;
+ * all messages are always public and can be distributed freely.
+ * Joins may be announced, but this is not required.
*/
- GNUNET_PSYC_AF_STREAMABLE = 2,
+ GNUNET_PSYC_CHANNEL_ANONYMOUS = 0,
/**
- * Argument is variable-length, incrementally supplied
- * data stream.
+ * The master must approve membership to the channel, messages must only be
+ * distributed to current channel slaves. This includes the channel
+ * state as well as transient messages.
*/
- GNUNET_PSYC_AF_STREAM = 3,
+ GNUNET_PSYC_CHANNEL_PRIVATE
+ = GNUNET_PSYC_CHANNEL_ADMISSION_CONTROL
+ | GNUNET_PSYC_CHANNEL_RESTRICTED_HISTORY
+#if IDEAS_FOR_FUTURE
/**
- * Argument is zero-terminated character array.
+ * Anyone can freely join the channel (no approval required);
+ * however, messages must only be distributed to current channel
+ * slaves, so the master must still acknowledge that the slave
+ * joined before transient messages are delivered. As approval is
+ * guaranteed, the presistent channel state can be synchronized freely
+ * immediately, prior to master confirmation.
*/
- GNUNET_PSYC_AF_ZERO_TERMINATED_CHARARRAY = 4,
+ GNUNET_PSYC_CHANNEL_OPEN
+ = GNUNET_PSYC_CHANNEL_RESTRICTED_HISTORY,
/**
- * Argument is variable-length UTF-8 encoded, zero-terminated string.
+ * The master must approve joins to the channel, but past messages can be
+ * freely distributed to slaves.
*/
- GNUNET_PSYC_AF_UTF8 = 5,
+ GNUNET_PSYC_CHANNEL_CLOSED
+ = GNUNET_PSYC_CHANNEL_ADMISSION_CONTROL,
+#endif
+};
+
+enum GNUNET_PSYC_MessageFlags
+{
/**
- * Payload is an unsigned integer and might thus be encoded as an
- * integer when generating PSYC stream (useful if we want to
- * generate human-readable PSYC streams, instead of just always
- * using length-prefixed binary encodings). Note that it
- * is not sufficient to just test for this bit, as it is
- * also set for 'REAL' numbers!
+ * Default / no flags.
*/
- GNUNET_PSYC_AF_UNSIGNED_INTEGER = 8,
+ GNUNET_PSYC_MESSAGE_DEFAULT = 0,
/**
- * Payload is an unsigned integer and might thus be encoded as an
- * integer when generating PSYC stream (useful if we want to
- * generate human-readable PSYC streams, instead of just always
- * using length-prefixed binary encodings). Note that it
- * is not sufficient to just test for this bit, as it is
- * also set for 'REAL' numbers!
+ * Historic message, retrieved from PSYCstore.
*/
- GNUNET_PSYC_AF_SIGNED_INTEGER = 16,
+ GNUNET_PSYC_MESSAGE_HISTORIC = 1 << 0,
/**
- * Payload is a 'real' number (float or double). We save a bit here
- * as a number cannot be both SIGNED and UNSIGNED, so setting both
- * bits is fine to use for REALs.
+ * Request from slave to master.
*/
- GNUNET_PSYC_AF_REAL_NUMBER = 24
+ GNUNET_PSYC_MESSAGE_REQUEST = 1 << 1,
+ /**
+ * Message can be delivered out of order.
+ */
+ GNUNET_PSYC_MESSAGE_ORDER_ANY = 1 << 2
};
/**
- * Argument descriptors are used to describe types that can be
- * embedded in a PSYC stream. For example, a "uint32_t" is
- * described as 4-byte, fixed-length data, whereas a movie
- * would be a variable-size, streaming argument.
+ * Values for the @a state_delta field of GNUNET_PSYC_MessageHeader.
*/
-struct GNUNET_PSYC_ArgumentDescriptor
+enum GNUNET_PSYC_StateDeltaValues
{
+ GNUNET_PSYC_STATE_RESET = 0,
+
+ GNUNET_PSYC_STATE_NOT_MODIFIED = UINT64_MAX
+};
- /**
- * Required length of the argument in bytes, zero for
- * variable-size arguments.
- */
- size_t arg_len;
+GNUNET_NETWORK_STRUCT_BEGIN
+
+/**
+ * A PSYC message.
+ *
+ * Used for single-fragment messages e.g. in a join request or response.
+ */
+struct GNUNET_PSYC_Message
+{
/**
- * Flags describing additional properties of the argument,
- * such as variable-size, streaming or 0-termination. This
- * argument is a bitfield.
+ * Message header with size and type information.
*/
- enum GNUNET_PSYC_ArgumentFlags flags;
+ struct GNUNET_MessageHeader header;
+ /* Followed by concatenated PSYC message parts:
+ * messages with GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_* types
+ */
};
/**
- * Convenience macro to define an argument descriptor for
- * some fixed-size C data type.
+ * Header of a PSYC message.
*
- * @param pt C data type (i.e. 'uint32_t')
+ * The PSYC service adds this when delivering the message to local clients,
+ * not present on the multicast layer.
*/
-#define GNUNET_PSYC_AD_C_TYPE(pt) { sizeof (pt), GNUNET_PSYC_AF_FIXED_SIZE }
+struct GNUNET_PSYC_MessageHeader
+{
+ /**
+ * Generic message header with size and type information.
+ */
+ struct GNUNET_MessageHeader header;
-/**
- * Convenience macro to define an argument descriptor for
- * some fixed-size unsigned integer type.
- *
- * @param it C integer data type (i.e. 'uint32_t')
- */
-#define GNUNET_PSYC_AD_C_UINT_TYPE(it) { sizeof (it), GNUNET_PSYC_AF_FIXED_SIZE | GNUNET_PSYC_AF_UNSIGNED_INTEGER }
+ /**
+ * Flags for this message fragment.
+ *
+ * @see enum GNUNET_PSYC_MessageFlags
+ */
+ uint32_t flags GNUNET_PACKED;
-/**
- * Argument descriptor for a 'uint8_t' argument.
- */
-#define GNUNET_PSYC_AD_UINT8 GNUNET_PSYC_AD_C_UINT_TYPE(uint8_t)
+ /**
+ * Number of the message this message part belongs to.
+ * Monotonically increasing from 1.
+ */
+ uint64_t message_id GNUNET_PACKED;
+
+ /**
+ * Byte offset of this @e fragment of the @e message.
+ * FIXME: use data_offset instead
+ */
+ uint64_t fragment_offset GNUNET_PACKED;
+
+ /**
+ * Sending slave's public key.
+ * Not set if the message is from the master.
+ */
+ struct GNUNET_CRYPTO_EcdsaPublicKey slave_key;
+
+ /* Followed by concatenated PSYC message parts:
+ * messages with GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_* types
+ */
+};
-/**
- * Argument descriptor for a 'uint16_t' argument.
- */
-#define GNUNET_PSYC_AD_UINT16 GNUNET_PSYC_AD_C_UINT_TYPE(uint16_t)
/**
- * Argument descriptor for a 'uint32_t' argument.
+ * The method of a message.
*/
-#define GNUNET_PSYC_AD_UINT32 GNUNET_PSYC_AD_C_UINT_TYPE(uint32_t)
+struct GNUNET_PSYC_MessageMethod
+{
+ /**
+ * Type: GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_METHOD
+ */
+ struct GNUNET_MessageHeader header;
+
+ /**
+ * OR'ed GNUNET_PSYC_MasterTransmitFlags
+ */
+ uint32_t flags GNUNET_PACKED;
+
+ /**
+ * Number of message IDs since the last message that contained state
+ * operations. @see enum GNUNET_PSYC_StateDeltaValues
+ */
+ uint64_t state_delta GNUNET_PACKED;
+
+ /* Followed by NUL-terminated method name. */
+};
+
/**
- * Argument descriptor for a 'uint64_t' argument.
+ * A modifier of a message.
*/
-#define GNUNET_PSYC_AD_UINT64 GNUNET_PSYC_AD_C_UINT_TYPE(uint64_t)
+struct GNUNET_PSYC_MessageModifier
+{
+ /**
+ * Type: GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_MODIFIER
+ */
+ struct GNUNET_MessageHeader header;
+
+ /**
+ * Size of value.
+ */
+ uint32_t value_size GNUNET_PACKED;
+
+ /**
+ * Size of name, including NUL terminator.
+ */
+ uint16_t name_size GNUNET_PACKED;
+
+ /**
+ * enum GNUNET_ENV_Operator
+ */
+ uint8_t oper;
+
+ /* Followed by NUL-terminated name, then the value. */
+};
+
+
+struct GNUNET_PSYC_CountersResultMessage
+{
+ /**
+ * Type: GNUNET_MESSAGE_TYPE_PSYC_RESULT_COUNTERS
+ */
+ struct GNUNET_MessageHeader header;
+
+ /**
+ * Status code for the operation.
+ */
+ uint32_t result_code GNUNET_PACKED;
+
+ /**
+ * Last message ID sent to the channel.
+ */
+ uint64_t max_message_id GNUNET_PACKED;
+};
+
/**
- * Convenience macro to define an argument descriptor for
- * a 0-terminated, variable-length UTF-8 string.
+ * Join request sent to a PSYC master.
*/
-#define GNUNET_PSYC_AD_UTF8 { 0, GNUNET_PSYC_AF_UTF8 }
-
+struct GNUNET_PSYC_JoinRequestMessage
+{
+ /**
+ * Type: GNUNET_MESSAGE_TYPE_PSYC_MASTER_JOIN_REQUEST
+ */
+ struct GNUNET_MessageHeader header;
+ /**
+ * Public key of the joining slave.
+ */
+ struct GNUNET_CRYPTO_EcdsaPublicKey slave_key;
-/* TODO: add more convenience macros for argument types later as needed */
+ /* Followed by struct GNUNET_MessageHeader join_request */
+};
/**
- * Abstract argument passed to a GNUNET_PSYC_Method.
+ * Join decision sent in reply to a join request.
*/
-struct GNUNET_PSYC_Argument
+struct GNUNET_PSYC_JoinDecisionMessage
{
+ /**
+ * Type: GNUNET_MESSAGE_TYPE_PSYC_JOIN_DECISION
+ */
+ struct GNUNET_MessageHeader header;
/**
- * Data of the argument.
+ * #GNUNET_YES if the slave was admitted.
*/
- const void *data;
+ int32_t is_admitted;
/**
- * Number of bytes in 'data', guaranteed to be the argument
- * descriptor 'arg_len' MINUS 'data_off' unless
- * GNUNET_PSYC_AF_VARIABLE_SIZE was set.
+ * Public key of the joining slave.
+ * Only set when the master is sending the decision,
+ * not set when a slave is receiving it.
*/
- size_t data_size;
+ struct GNUNET_CRYPTO_EcdsaPublicKey slave_key;
+ /* Followed by struct GNUNET_MessageHeader join_response */
+};
+
+
+enum GNUNET_PSYC_HistoryReplayFlags
+{
/**
- * Offset of 'data' in the overall argument,
- * always zero unless GNUNET_PSYC_AF_STREAMABLE was
- * set for the argument.
+ * Replay locally available messages.
*/
- uint64_t data_off;
+ GNUNET_PSYC_HISTORY_REPLAY_LOCAL = 0,
/**
- * Total number of bytes to be expected in 'data',
- * UINT64_MAX for 'unknown' (i.e. for "infinite"
- * streams).
+ * Replay messages from remote peers if not found locally.
*/
- uint64_t value_size;
+ GNUNET_PSYC_HISTORY_REPLAY_REMOTE = 1,
};
-/**
- * Method called from PSYC upon receiving a message indicating a call
- * to a 'method'. The arguments given will match those of the
- * respective argument descriptor. If some arguments were marked
- * as 'streaming', the function can return a value other than -1
- * to request "more" of the data for that argument. Note that all
- * non-streaming arguments will be replayed in full for each additional
- * invocation of the method. Using more than one streaming argument
- * is possible, in which case PSYC will ONLY advance the stream of the
- * argument for which the index was returned; the values of other
- * streaming arguments will be replayed at the current offset.
- *
- * Returning a value other than -1 or that of a streaming argument is
- * not allowed. Returning -1 does not indicate an error; it simply
- * indicates that the client wants to proceed with the next method
- * (and not see the rest of the data from any of the streaming
- * arguments).
- *
- * TODO: note that this API currently doesn't allow for seeking
- * in streaming data (very advanced feature)
- *
- * @param cls closure
- * @param full_method_name original method name from PSYC (may be more
- * specific than the registered method name due to try&slice matching)
- * @param sender who transmitted the message (origin, except for messages
- * from one of the members to the origin)
- * @param message_id unique message counter for this message
- * @param group_generation group generation counter for this message
- * @param argc number of arguments in argv
- * @param argv array of argc arguments to the method
- * @return -1 if we're finished with this method, index
- * of a streaming argument for which more data is
- * requested otherwise
- */
-typedef int (*GNUNET_PSYC_Method)(void *cls,
- const char *full_method_name,
- const struct GNUNET_PeerIdentity *sender,
- unsigned int argc,
- const struct GNUNET_PSYC_Argument *argv);
-
-
-/**
- * Descriptor for a PSYC method and its arguments. Here is how this
- * is expected to be used. Imagine we have a method with the
- * following signature:
- * <pre>
- * static void
- * logger (void *cls, uint32_t log_level, const char *log_message);
- * </pre>
- * where 'cls' is supposed to be a 'FILE *'.
- * Then for PSYC to call this method with 'stderr' for 'cls',
- * we would provide the following method descriptor:
- * <pre>
- * .method_name = "log";
- * .method = &wrap_logger;
- * .method_cls = stderr;
- * .argc = 2;
- * .argv = { GNUNET_PSYC_AD_UINT32, GNUNET_PSYC_AD_UTF8 };
- * </pre>
- * and define <tt>wrap_logger</tt> as follows:
- * <pre>
- * static void
- * wrap_logger (void *cls, const char full_method_name,
- * const struct GNUNET_PeerIdentity *sender,
- * unsigned int argc, const struct GNUNET_PSYC_Argument *argv)
- * {
- * uint32_t *log_level = argv[0].data;
- * const char *log_message = argv[1].data;
- * logger (cls, *log_level, log_message);
- * }
- * </pre>
- * Note that the PSYC library will take care of making sure
- * that 'argv[0].data_size == 4' and that the log message
- * is 0-terminated, as those requirements were specified
- * in the method descriptor for those arguments. Finally,
- * it is conceivable to generate the wrappers and method
- * descriptors automatically, as they are trivial.
- * <p>
- * Note that due to try & slice, the given full method name
- * might be more specific; for example, the given method
- * might be called for a request to "log_warning" instead
- * of just a request to "log".
- */
-struct GNUNET_PSYC_MethodDescriptor
+struct GNUNET_PSYC_HistoryRequestMessage
{
+ /**
+ * Type: GNUNET_MESSAGE_TYPE_PSYC_CHANNEL_HISTORY_REPLAY
+ */
+ struct GNUNET_MessageHeader header;
+
+ /**
+ * @see enum GNUNET_PSYC_HistoryReplayFlags
+ */
+ uint32_t flags GNUNET_PACKED;
+
+ /**
+ * ID for this operation.
+ */
+ uint64_t op_id GNUNET_PACKED;
+
+ uint64_t start_message_id GNUNET_PACKED;
+
+ uint64_t end_message_id GNUNET_PACKED;
+
+ uint64_t message_limit GNUNET_PACKED;
+
+ /* Followed by NUL-terminated method name prefix. */
+};
+
+struct GNUNET_PSYC_StateRequestMessage
+{
/**
- * Name of the method to be used in try-and-slice matching.
+ * Types:
+ * - GNUNET_MESSAGE_TYPE_PSYC_CHANNEL_STATE_GET
+ * - GNUNET_MESSAGE_TYPE_PSYC_CHANNEL_STATE_GET_PREFIX
*/
- const char *method_name;
+ struct GNUNET_MessageHeader header;
+
+ uint32_t reserved GNUNET_PACKED;
/**
- * Function to call. Note that if a more specific handler exists
- * as well, the more generic handler will not be invoked.
+ * ID for this operation.
*/
- GNUNET_PSYC_Method method;
+ uint64_t op_id GNUNET_PACKED;
+
+ /* Followed by NUL-terminated name. */
+};
+
+/**** service -> library ****/
+
+
+/**
+ * Answer from service to client about last operation.
+ */
+struct GNUNET_PSYC_OperationResultMessage
+{
/**
- * Closure for the method (this argument and the 'sender' argument
- * are both not included in 'argc').
+ * Types:
+ * - GNUNET_MESSAGE_TYPE_PSYC_RESULT_CODE
+ * - GNUNET_MESSAGE_TYPE_PSYC_CHANNEL_STATE_RESULT
*/
- void *method_cls;
+ struct GNUNET_MessageHeader header;
+
+ uint32_t reserved GNUNET_PACKED;
/**
- * Number of arguments to pass to the method (length of the 'ads'
- * array).
+ * Operation ID.
*/
- unsigned int argc;
+ uint64_t op_id GNUNET_PACKED;
/**
- * Array of 'argc' argument descriptors describing the arguments to
- * be passed to the method. Non-matching method calls will be
- * ignored (but logged). Note that the 'ads' of all methods with
- * the same method name prefix should be identical.
+ * Status code for the operation.
+ */
+ uint64_t result_code GNUNET_PACKED;
+
+ /* Followed by:
+ * - on error: NUL-terminated error message
+ * - on success: one of the following message types
+ *
+ * For a STATE_RESULT, one of:
+ * - GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_MODIFIER
+ * - GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_MOD_CONT
+ * - GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_END
*/
- const struct GNUNET_PSYC_ArgumentDescriptor *ads;
+};
+
+GNUNET_NETWORK_STRUCT_END
+
+
+#define GNUNET_PSYC_MODIFIER_MAX_PAYLOAD \
+ GNUNET_MULTICAST_FRAGMENT_MAX_PAYLOAD \
+ - sizeof (struct GNUNET_PSYC_MessageModifier)
+
+#define GNUNET_PSYC_MOD_CONT_MAX_PAYLOAD \
+ GNUNET_MULTICAST_FRAGMENT_MAX_PAYLOAD \
+ - sizeof (struct GNUNET_MessageHeader)
+
+#define GNUNET_PSYC_DATA_MAX_PAYLOAD \
+ GNUNET_MULTICAST_FRAGMENT_MAX_PAYLOAD \
+ - sizeof (struct GNUNET_MessageHeader)
+
+/**
+ * PSYC message part processing states.
+ */
+enum GNUNET_PSYC_MessageState
+{
+ GNUNET_PSYC_MESSAGE_STATE_START = 0,
+ GNUNET_PSYC_MESSAGE_STATE_HEADER = 1,
+ GNUNET_PSYC_MESSAGE_STATE_METHOD = 2,
+ GNUNET_PSYC_MESSAGE_STATE_MODIFIER = 3,
+ GNUNET_PSYC_MESSAGE_STATE_MOD_CONT = 4,
+ GNUNET_PSYC_MESSAGE_STATE_DATA = 5,
+ GNUNET_PSYC_MESSAGE_STATE_END = 6,
+ GNUNET_PSYC_MESSAGE_STATE_CANCEL = 7,
+ GNUNET_PSYC_MESSAGE_STATE_ERROR = 8,
};
/**
- * Handle for the origin of a psyc group.
+ * Handle that identifies a join request.
+ *
+ * Used to match calls to #GNUNET_PSYC_JoinCallback to the
+ * corresponding calls to GNUNET_PSYC_join_decision().
*/
-struct GNUNET_PSYC_Origin;
+struct GNUNET_PSYC_JoinHandle;
/**
- * Start a psyc group. Will create a multicast group identified by
- * the given public key. Messages recevied from group members will be
- * given to the respective handler methods. If a new member wants to
- * join a group, the "join" method handler will be invoked; the join
- * handler must then generate a "join" message to approve the joining
- * of the new member. The origin can also change group membership
- * without explicit requests. Note that PSYC doesn't itself "understand"
- * join or leave messages, the respective methods must call other
- * PSYC functions to inform PSYC about the meaning of the respective
- * events.
+ * Method called from PSYC upon receiving a message.
*
- * @param cfg configuration to use (to connect to PSYC service)
- * @param method_count number of methods in 'methods' array
- * @param methods functions to invoke on messages received from members,
- * typcially at least contains functions for 'join' and 'leave'.
- * @param priv_key ECC key that will be used to sign messages for this
- * psyc session; public key is used to identify the
- * psyc group; FIXME: we'll likely want to use
- * NOT the p521 curve here, but a cheaper one in the future
- * @param join_policy what is the membership policy of the group?
- * @return handle for the origin, NULL on error
+ * @param cls Closure.
+ * @param message_id Sequence number of the message.
+ * @param flags OR'ed GNUNET_PSYC_MessageFlags
+ * @param msg Message part, one of the following types:
*/
-struct GNUNET_PSYC_Origin *
-GNUNET_PSYC_origin_start (const struct GNUNET_CONFIGURATION_Handle *cfg,
- unsigned int method_count,
- const struct GNUNET_PSYC_MethodDescriptor *methods,
- const struct GNUNET_CRYPTO_EccPrivateKey *priv_key,
- enum GNUNET_MULTICAST_JoinPolicy join_policy);
+typedef void
+(*GNUNET_PSYC_MessageCallback) (void *cls,
+ uint64_t message_id,
+ uint32_t flags,
+ const struct GNUNET_PSYC_MessageHeader *msg);
/**
- * Update channel state. The state of a channel must fit into the
- * memory of each member (and the origin); large values that require
- * streaming must only be passed as streaming arguments to methods.
- * State updates might not be transmitted to group members until
- * the next call to 'GNUNET_PSYC_origin_broadcast_call_method'.
+ * Method called from PSYC upon receiving part of a message.
*
- * @param origin handle to the psyc group / channel
- * @param full_state_name name of the field in the channel state to change
- * @param data_size number of bytes in data
- * @param data new state value
+ * @param cls
+ * Closure.
+ * @param slave_key
+ * Public key of the slave sending the message.
+ * Only set for channel master.
+ * @param message_id
+ * Sequence number of the message.
+ * @param flags
+ * OR'ed GNUNET_PSYC_MessageFlags
+ * @param data_offset
+ * Byte offset of data, only set if @a msg has a type
+ * #GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_DATA
+ * @param msg Message part, one of the following types:
+ * - #GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_HEADER
+ * - #GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_METHOD
+ * - #GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_MODIFIER
+ * - #GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_MOD_CONT
+ * - #GNUNET_MESSAGE_TYPE_PSYC_MESSAGE_DATA
+ * or NULL if an error occurred while receiving a message.
*/
-void
-GNUNET_PSYC_origin_update_state (struct GNUNET_PSYC_Origin *origin,
- const char *full_state_name,
- size_t data_size,
- const void *data);
+typedef void
+(*GNUNET_PSYC_MessagePartCallback) (void *cls,
+ const struct GNUNET_CRYPTO_EcdsaPublicKey *slave_key,
+ uint64_t message_id,
+ uint32_t flags,
+ uint64_t data_offset,
+ const struct GNUNET_MessageHeader *msg);
+
+
+/**
+ * Method called from PSYC upon receiving a join request.
+ *
+ * @param cls
+ * Closure.
+ * @param slave_key
+ * Public key of the slave requesting join.
+ * @param join_msg
+ * Join message sent along with the request.
+ * @param jh
+ * Join handle to use with GNUNET_PSYC_join_decision()
+ */
+typedef void
+(*GNUNET_PSYC_JoinRequestCallback) (void *cls,
+ const struct GNUNET_PSYC_JoinRequestMessage *req,
+ const struct GNUNET_CRYPTO_EcdsaPublicKey *slave_key,
+ const struct GNUNET_PSYC_Message *join_msg,
+ struct GNUNET_PSYC_JoinHandle *jh);
/**
- * Data needed to construct a PSYC message to call a method.
+ * 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
+ * #GNUNET_PSYC_JoinCallback.
+ *
+ * @param jh Join request handle.
+ * @param is_admitted
+ * #GNUNET_YES if the join is approved,
+ * #GNUNET_NO if it is disapproved,
+ * #GNUNET_SYSERR if we cannot answer the request.
+ * @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
+ * are already part of the multicast group and might thus be willing
+ * to help with routing). If empty, only this local peer (which must
+ * be the multicast origin) is a good candidate for building the
+ * multicast tree. Note that it is unnecessary to specify our own
+ * peer identity in this array.
+ * @param join_resp Application-dependent join response message to send along
+ * with the decision.
+ *
+ * @return #GNUNET_OK on success,
+ * #GNUNET_SYSERR if @a join_resp is too large.
*/
-struct GNUNET_PSYC_CallData
+int
+GNUNET_PSYC_join_decision (struct GNUNET_PSYC_JoinHandle *jh,
+ int is_admitted,
+ uint32_t relay_count,
+ const struct GNUNET_PeerIdentity *relays,
+ const struct GNUNET_PSYC_Message *join_resp);
+
+
+/**
+ * Handle for the master of a PSYC channel.
+ */
+struct GNUNET_PSYC_Master;
+
+
+/**
+ * Function called after connected to the PSYC service
+ * and the channel master started.
+ *
+ * Also called when reconnected to the service
+ * after the connection closed unexpectedly.
+ *
+ * @param cls
+ * Closure.
+ * @param result
+ * #GNUNET_YES if there were already messages sent to the channel,
+ * #GNUNET_NO if the message history is empty,
+ * #GNUNET_SYSERR on error.
+ * @param max_message_id
+ * Last message ID sent to the channel.
+ */
+typedef void
+(*GNUNET_PSYC_MasterStartCallback) (void *cls, int result,
+ uint64_t max_message_id);
+
+
+/**
+ * Start a PSYC master channel.
+ *
+ * Will start a multicast group identified by the given ECC key. Messages
+ * received from group members will be given to the respective handler methods.
+ * If a new member wants to join a group, the "join" method handler will be
+ * invoked; the join handler must then generate a "join" message to approve the
+ * joining of the new member. The channel can also change group membership
+ * without explicit requests. Note that PSYC doesn't itself "understand" join
+ * or part messages, the respective methods must call other PSYC functions to
+ * inform PSYC about the meaning of the respective events.
+ *
+ * @param cfg Configuration to use (to connect to PSYC service).
+ * @param channel_key ECC key that will be used to sign messages for this
+ * PSYC session. The public key is used to identify the PSYC channel.
+ * Note that end-users will usually not use the private key directly, but
+ * rather look it up in GNS for places managed by other users, or select
+ * a file with the private key(s) when setting up their own channels
+ * FIXME: we'll likely want to use NOT the p521 curve here, but a cheaper
+ * one in the future.
+ * @param policy Channel policy specifying join and history restrictions.
+ * Used to automate join decisions.
+ * @param master_start_cb Function to invoke after the channel master started.
+ * @param join_request_cb Function to invoke when a slave wants to join.
+ * @param message_cb Function to invoke on message parts sent to the channel
+ * and received from slaves
+ * @param cls Closure for @a method and @a join_cb.
+ *
+ * @return Handle for the channel master, NULL on error.
+ */
+struct GNUNET_PSYC_Master *
+GNUNET_PSYC_master_start (const struct GNUNET_CONFIGURATION_Handle *cfg,
+ const struct GNUNET_CRYPTO_EddsaPrivateKey *channel_key,
+ enum GNUNET_PSYC_Policy policy,
+ GNUNET_PSYC_MasterStartCallback master_start_cb,
+ GNUNET_PSYC_JoinRequestCallback join_request_cb,
+ GNUNET_PSYC_MessageCallback message_cb,
+ GNUNET_PSYC_MessagePartCallback message_part_cb,
+ void *cls);
+
+
+/**
+ * Function called to provide data for a transmission via PSYC.
+ *
+ * Note that returning #GNUNET_YES 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_PSYC_master_transmit_resume().
+ * #GNUNET_YES if this completes the transmission (all data supplied)
+ */
+typedef int
+(*GNUNET_PSYC_TransmitNotifyData) (void *cls,
+ uint16_t *data_size,
+ void *data);
+
+/**
+ * Function called to provide a modifier for a transmission via PSYC.
+ *
+ * Note that returning #GNUNET_YES 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 modifier's name and value.
+ * The function must copy at most @a data_size bytes to @a data.
+ * When this callback is first called for a modifier, @a data should
+ * contain: "name\0value". If the whole value does not fit, subsequent
+ * calls to this function should write continuations of the value to
+ * @a data.
+ * @param[out] oper Where to write the operator of the modifier.
+ * Only needed during the first call to this callback at the beginning
+ * of the modifier. In case of subsequent calls asking for value
+ * continuations @a oper is set to #NULL.
+ * @param[out] full_value_size Where to write the full size of the value.
+ * Only needed during the first call to this callback at the beginning
+ * of the modifier. In case of subsequent calls asking for value
+ * continuations @a value_size is set to #NULL.
+ * @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 for the modifier's value (the name must be always returned
+ * during the first call to this callback).
+ * If 0 is returned in @a data_size the transmission is paused,
+ * and can be resumed with GNUNET_PSYC_master_transmit_resume().
+ * #GNUNET_YES if this completes the modifier (the whole value is supplied).
+ */
+typedef int
+(*GNUNET_PSYC_TransmitNotifyModifier) (void *cls,
+ uint16_t *data_size,
+ void *data,
+ uint8_t *oper,
+ uint32_t *full_value_size);
+
+/**
+ * Flags for transmitting messages to a channel by the master.
+ */
+enum GNUNET_PSYC_MasterTransmitFlags
{
+ GNUNET_PSYC_MASTER_TRANSMIT_NONE = 0,
/**
- * Name of the function to call. This name may be more specific
- * than the registered method name due to try&slice matching.
+ * Whether this message should reset the channel state,
+ * i.e. remove all previously stored state variables.
*/
- const char *full_method_name;
+
+ GNUNET_PSYC_MASTER_TRANSMIT_STATE_RESET = 1 << 0,
/**
- * Number of arguments to pass (other than closure and sender),
- * length of the 'argv' array.
+ * Whether this message contains any state modifiers.
*/
- unsigned int argc;
+ GNUNET_PSYC_MASTER_TRANSMIT_STATE_MODIFY = 1 << 1,
/**
- * Arguments to pass to the function.
+ * Add PSYC header variable with the hash of the current channel state.
*/
- const struct GNUNET_PSYC_Argument *argv;
+ GNUNET_PSYC_MASTER_TRANSMIT_STATE_HASH = 1 << 2,
+ /**
+ * Whether we need to increment the group generation counter after
+ * transmitting this message.
+ */
+ GNUNET_PSYC_MASTER_TRANSMIT_INC_GROUP_GEN = 1 << 3
};
/**
- * Send a message to call a method to all members in the psyc group.
+ * Handle for a pending PSYC transmission operation.
+ */
+struct GNUNET_PSYC_MasterTransmitHandle;
+
+
+/**
+ * Send a message to call a method to all members in the PSYC channel.
+ *
+ * @param master Handle to the PSYC channel.
+ * @param method_name Which method should be invoked.
+ * @param notify_mod Function to call to obtain modifiers.
+ * @param notify_data Function to call to obtain fragments of the data.
+ * @param notify_cls Closure for @a notify_mod and @a notify_data.
+ * @param flags Flags for the message being transmitted.
+ * @return Transmission handle, NULL on error (i.e. more than one request queued).
+ */
+struct GNUNET_PSYC_MasterTransmitHandle *
+GNUNET_PSYC_master_transmit (struct GNUNET_PSYC_Master *master,
+ const char *method_name,
+ GNUNET_PSYC_TransmitNotifyModifier notify_mod,
+ GNUNET_PSYC_TransmitNotifyData notify_data,
+ void *notify_cls,
+ enum GNUNET_PSYC_MasterTransmitFlags flags);
+
+
+/**
+ * Resume transmission to the channel.
*
- * @param origin handle to the psyc group
- * @param increment_group_generation GNUNET_YES if we need to increment
- * the group generation counter after transmitting this message
- * @param call_data data needed to determine how to call which method
- * @param message_id set to the unique message ID that was generated for
- * this message
- * @param group_generation set to the group generation used for this
- * message
- * FIXME: change to notify_transmit_ready-style to wait for ACKs?
- * that'd also help with streaming arguments!
- * => need to change multicast API first as well!
+ * @param th Handle of the request that is being resumed.
*/
void
-GNUNET_PSYC_origin_broadcast_call_method (struct GNUNET_PSYC_Origin *origin,
- int increment_group_generation,
- const struct GNUNET_PSYC_CallData *call_data,
- uint64_t *message_id,
- uint64_t *group_generation);
+GNUNET_PSYC_master_transmit_resume (struct GNUNET_PSYC_MasterTransmitHandle *th);
/**
- * End a psyc group.
+ * Abort transmission request to channel.
*
- * @param origin psyc group to terminate
+ * @param th Handle of the request that is being aborted.
*/
void
-GNUNET_PSYC_origin_end (struct GNUNET_PSYC_Origin *origin);
+GNUNET_PSYC_master_transmit_cancel (struct GNUNET_PSYC_MasterTransmitHandle *th);
/**
- * Handle to access PSYC group operations for all members.
+ * Stop a PSYC master channel.
+ *
+ * @param master
+ * PSYC channel master to stop.
+ * @param keep_active
+ * Keep place active after last application disconnected.
+ * @param stop_cb
+ * Function called after the master stopped
+ * and disconnected from the psyc service.
+ * @param stop_cls
+ * Closure for @a part_cb.
*/
-struct GNUNET_PSYC_Group;
+void
+GNUNET_PSYC_master_stop (struct GNUNET_PSYC_Master *master,
+ int keep_active,
+ GNUNET_ContinuationCallback stop_cb,
+ void *stop_cls);
/**
- * Convert 'origin' to a 'group' handle to access the 'group' APIs.
- *
- * @param origin origin handle
- * @return group handle, valid for as long as 'origin' is valid
- */
-struct GNUNET_PSYC_Group *
-GNUNET_PSYC_origin_get_group (struct GNUNET_PSYC_Origin *origin);
+ * Handle for a PSYC channel slave.
+ */
+struct GNUNET_PSYC_Slave;
/**
- * Add a member to the group. Note that this will NOT generate any
- * PSYC traffic, it will merely update the local data base to modify
- * how we react to 'membership test' queries. The origin still needs to
- * explicitly transmit a 'leave' message to notify other group members
- * and they then also must still call this function in their respective
- * methods handling the 'leave' message. This way, how 'join' and 'leave'
- * operations are exactly implemented is still up to the application;
- * for example, there might be a 'leave_all' message to kick out everyone.
+ * Function called after the slave connected to the PSYC service.
*
- * Note that group members are explicitly trusted to perform these
- * operations correctly; not doing so correctly will result in either
- * denying members access or offering access to group data to
- * non-members.
+ * Also called when reconnected to the service
+ * after the connection closed unexpectedly.
+ *
+ * @param cls
+ * Closure.
+ * @param result
+ * #GNUNET_YES if there were already messages sent to the channel,
+ * #GNUNET_NO if the message history is empty,
+ * #GNUNET_SYSERR on error.
+ * @param max_message_id
+ * Last message ID sent to the channel.
+ */
+typedef void
+(*GNUNET_PSYC_SlaveConnectCallback) (void *cls, int result,
+ uint64_t max_message_id);
+
+
+/**
+ * Method called to inform about the decision in response to a join request.
+ *
+ * If @a is_admitted is not #GNUNET_YES, then sending messages to the channel is
+ * not possible, but earlier history can be still queried.
+ *
+ * @param cls Closure.
+ * @param is_admitted #GNUNET_YES or #GNUNET_NO or #GNUNET_SYSERR
+ * @param join_msg Application-dependent join message from the origin.
+ */
+typedef void
+(*GNUNET_PSYC_JoinDecisionCallback) (void *cls,
+ const struct GNUNET_PSYC_JoinDecisionMessage *dcsn,
+ int is_admitted,
+ const struct GNUNET_PSYC_Message *join_msg);
+
+
+/**
+ * Join a PSYC channel.
+ *
+ * The entity joining is always the local peer. The user must immediately use
+ * the GNUNET_PSYC_slave_transmit() functions to transmit a @e join_msg to the
+ * channel; if the join request succeeds, the channel state (and @e recent
+ * method calls) will be replayed to the joining member. There is no explicit
+ * notification on failure (as the channel may simply take days to approve,
+ * and disapproval is simply being ignored).
+ *
+ * @param cfg Configuration to use.
+ * @param channel_key ECC public key that identifies the channel we wish to join.
+ * @param slave_key ECC private-public key pair that identifies the slave, and
+ * used by multicast to sign the join request and subsequent unicast
+ * requests sent to the master.
+ * @param origin Peer identity of the origin.
+ * @param relay_count Number of peers in the @a relays array.
+ * @param relays Peer identities of members of the multicast group, which serve
+ * as relays and used to join the group at.
+ * @param message_cb Function to invoke on message parts received from the
+ * channel, typically at least contains method handlers for @e join and
+ * @e part.
+ * @param slave_connect_cb Function invoked once we have connected to the
+ * PSYC service.
+ * @param join_decision_cb Function invoked once we have received a join
+ * decision.
+ * @param cls Closure for @a message_cb and @a slave_joined_cb.
+ * @param method_name Method name for the join request.
+ * @param env Environment containing transient variables for the request, or NULL.
+ * @param data Payload for the join message.
+ * @param data_size Number of bytes in @a data.
+ *
+ * @return Handle for the slave, NULL on error.
+ */
+struct GNUNET_PSYC_Slave *
+GNUNET_PSYC_slave_join (const struct GNUNET_CONFIGURATION_Handle *cfg,
+ const struct GNUNET_CRYPTO_EddsaPublicKey *channel_key,
+ const struct GNUNET_CRYPTO_EcdsaPrivateKey *slave_key,
+ const struct GNUNET_PeerIdentity *origin,
+ uint32_t relay_count,
+ const struct GNUNET_PeerIdentity *relays,
+ GNUNET_PSYC_MessageCallback message_cb,
+ GNUNET_PSYC_MessagePartCallback message_part_cb,
+ GNUNET_PSYC_SlaveConnectCallback slave_connect_cb,
+ GNUNET_PSYC_JoinDecisionCallback join_decision_cb,
+ void *cls,
+ const struct GNUNET_PSYC_Message *join_msg);
+
+
+/**
+ * Part a PSYC channel.
+ *
+ * Will terminate the connection to the PSYC service. Polite clients should
+ * first explicitly send a part request (via GNUNET_PSYC_slave_transmit()).
+ *
+ * @param slave
+ * Slave handle.
+ * @param keep_active
+ * Keep place active after last application disconnected.
+ * @param part_cb
+ * Function called after the slave parted the channel
+ * and disconnected from the psyc service.
+ * @param part_cls
+ * Closure for @a part_cb.
+ */
+void
+GNUNET_PSYC_slave_part (struct GNUNET_PSYC_Slave *slave,
+ int keep_active,
+ GNUNET_ContinuationCallback part_cb,
+ void *part_cls);
+
+
+/**
+ * Flags for transmitting messages to the channel master by a slave.
+ */
+enum GNUNET_PSYC_SlaveTransmitFlags
+{
+ GNUNET_PSYC_SLAVE_TRANSMIT_NONE = 0
+};
+
+
+/**
+ * Handle for a pending PSYC transmission operation.
+ */
+struct GNUNET_PSYC_SlaveTransmitHandle;
+
+
+/**
+ * Request a message to be sent to the channel master.
+ *
+ * @param slave Slave handle.
+ * @param method_name Which (PSYC) method should be invoked (on host).
+ * @param notify_mod Function to call to obtain modifiers.
+ * @param notify_data Function to call to obtain fragments of the data.
+ * @param notify_cls Closure for @a notify.
+ * @param flags Flags for the message being transmitted.
+ * @return Transmission handle, NULL on error (i.e. more than one request queued).
+ */
+struct GNUNET_PSYC_SlaveTransmitHandle *
+GNUNET_PSYC_slave_transmit (struct GNUNET_PSYC_Slave *slave,
+ const char *method_name,
+ GNUNET_PSYC_TransmitNotifyModifier notify_mod,
+ GNUNET_PSYC_TransmitNotifyData notify_data,
+ void *notify_cls,
+ enum GNUNET_PSYC_SlaveTransmitFlags flags);
+
+
+/**
+ * Resume transmission to the master.
+ *
+ * @param th Handle of the request that is being resumed.
+ */
+void
+GNUNET_PSYC_slave_transmit_resume (struct GNUNET_PSYC_SlaveTransmitHandle *th);
+
+
+/**
+ * Abort transmission request to master.
+ *
+ * @param th Handle of the request that is being aborted.
+ */
+void
+GNUNET_PSYC_slave_transmit_cancel (struct GNUNET_PSYC_SlaveTransmitHandle *th);
+
+
+/**
+ * Handle to access PSYC channel operations for both the master and slaves.
+ */
+struct GNUNET_PSYC_Channel;
+
+
+/**
+ * Convert a channel @a master to a @e channel handle to access the @e channel
+ * APIs.
+ *
+ * @param master Channel master handle.
+ * @return Channel handle, valid for as long as @a master is valid.
+ */
+struct GNUNET_PSYC_Channel *
+GNUNET_PSYC_master_get_channel (struct GNUNET_PSYC_Master *master);
+
+
+/**
+ * Convert @a slave to a @e channel handle to access the @e channel APIs.
+ *
+ * @param slave Slave handle.
+ * @return Channel handle, valid for as long as @a slave is valid.
+ */
+struct GNUNET_PSYC_Channel *
+GNUNET_PSYC_slave_get_channel (struct GNUNET_PSYC_Slave *slave);
+
+
+/**
+ * Add a slave to the channel's membership list.
*
- * @param group group handle
- * @param member which peer to add
- * @param message_id message ID for the message that changed the membership
- * @param group_generation the generation ID where the change went into effect
+ * Note that this will NOT generate any PSYC traffic, it will merely update the
+ * local database to modify how we react to <em>membership test</em> queries.
+ * The channel master still needs to explicitly transmit a @e join message to
+ * notify other channel members and they then also must still call this function
+ * in their respective methods handling the @e join message. This way, how @e
+ * join and @e part operations are exactly implemented is still up to the
+ * application; for example, there might be a @e part_all method to kick out
+ * everyone.
+ *
+ * Note that channel slaves are explicitly trusted to execute such methods
+ * correctly; not doing so correctly will result in either denying other slaves
+ * access or offering access to channel data to non-members.
+ *
+ * @param channel
+ * Channel handle.
+ * @param slave_key
+ * Identity of channel slave to add.
+ * @param announced_at
+ * ID of the message that announced the membership change.
+ * @param effective_since
+ * Addition of slave is in effect since this message ID.
+ * @param result_cb
+ * Function to call with the result of the operation.
+ * The @e result_code argument is #GNUNET_OK on success, or
+ * #GNUNET_SYSERR on error. In case of an error, the @e data argument
+ * can contain an optional error message.
+ * @param cls
+ * Closure for @a result_cb.
*/
void
-GNUNET_PSYC_group_member_admit (struct GNUNET_PSYC_Group *group,
- const struct GNUNET_PeerIdentity *member,
- uint64_t message_id,
- uint64_t group_generation);
+GNUNET_PSYC_channel_slave_add (struct GNUNET_PSYC_Channel *channel,
+ const struct GNUNET_CRYPTO_EcdsaPublicKey *slave_key,
+ uint64_t announced_at,
+ uint64_t effective_since,
+ GNUNET_ResultCallback result_cb,
+ void *cls);
/**
- * Remove a member from the group. Note that this will NOT generate any
- * PSYC traffic, it will merely update the local data base to modify
- * how we react to 'membership test' queries. The origin still needs to
- * explicitly transmit a 'leave' message to notify other group members
- * and they then also must still call this function in their respective
- * methods handling the 'leave' message. This way, how 'join' and 'leave'
- * operations are exactly implemented is still up to the application;
- * for example, there might be a 'leave_all' message to kick out everyone.
+ * Remove a slave from the channel's membership list.
+ *
+ * Note that this will NOT generate any PSYC traffic, it will merely update the
+ * local database to modify how we react to <em>membership test</em> queries.
+ * The channel master still needs to explicitly transmit a @e part message to
+ * notify other channel members and they then also must still call this function
+ * in their respective methods handling the @e part message. This way, how
+ * @e join and @e part operations are exactly implemented is still up to the
+ * application; for example, there might be a @e part_all message to kick out
+ * everyone.
*
- * Note that group members are explicitly trusted to perform these
+ * Note that channel members are explicitly trusted to perform these
* operations correctly; not doing so correctly will result in either
- * denying members access or offering access to group data to
+ * denying members access or offering access to channel data to
* non-members.
*
- * @param group group handle
- * @param member which peer to remove
- * @param message_id message ID for the message that changed the membership
- * @param group_generation the generation ID where the change went into effect
+ * @param channel
+ * Channel handle.
+ * @param slave_key
+ * Identity of channel slave to remove.
+ * @param announced_at
+ * ID of the message that announced the membership change.
+ * @param result_cb
+ * Function to call with the result of the operation.
+ * The @e result_code argument is #GNUNET_OK on success, or
+ * #GNUNET_SYSERR on error. In case of an error, the @e data argument
+ * can contain an optional error message.
+ * @param cls
+ * Closure for @a result_cb.
*/
void
-GNUNET_PSYC_group_member_kick (struct GNUNET_PSYC_Group *group,
- const struct GNUNET_PeerIdentity *member,
- uint64_t message_id,
- uint64_t group_generation);
+GNUNET_PSYC_channel_slave_remove (struct GNUNET_PSYC_Channel *channel,
+ const struct GNUNET_CRYPTO_EcdsaPublicKey
+ *slave_key,
+ uint64_t announced_at,
+ GNUNET_ResultCallback result_cb,
+ void *cls);
/**
- * Function called to inform a member about state values for a channel.
- *
- * @param cls closure
- * @param full_state_name full name of the state
- * @param data_size number of bytes in 'data'
- * @param data raw data of the state
+ * History request handle.
*/
-typedef void (*GNUNET_PSYC_StateCallback)(void *cls,
- const char *full_state_name,
- size_t data_size,
- const void *data);
+struct GNUNET_PSYC_HistoryRequest;
/**
- * Descriptor for an event handler handling PSYC state updates.
+ * Request to replay a part of the message history of the channel.
+ *
+ * Historic messages (but NOT the state at the time) will be replayed (given to
+ * the normal method handlers) if available and if access is permitted.
+ *
+ * @param channel
+ * Which channel should be replayed?
+ * @param start_message_id
+ * Earliest interesting point in history.
+ * @param end_message_id
+ * Last (inclusive) interesting point in history.
+ * @param method_prefix
+ * Retrieve only messages with a matching method prefix.
+ * @param flags
+ * OR'ed enum GNUNET_PSYC_HistoryReplayFlags
+ * @param result_cb
+ * Function to call when the requested history has been fully replayed.
+ * Once this function has been called, the client must not call
+ * GNUNET_PSYC_channel_history_replay_cancel() anymore.
+ * @param cls
+ * Closure for the callbacks.
+ *
+ * @return Handle to cancel history replay operation.
*/
-struct GNUNET_PSYC_StateHandler
-{
+struct GNUNET_PSYC_HistoryRequest *
+GNUNET_PSYC_channel_history_replay (struct GNUNET_PSYC_Channel *channel,
+ uint64_t start_message_id,
+ uint64_t end_message_id,
+ const char *method_prefix,
+ uint32_t flags,
+ GNUNET_PSYC_MessageCallback message_cb,
+ GNUNET_PSYC_MessagePartCallback message_part_cb,
+ GNUNET_ResultCallback result_cb,
+ void *cls);
- /**
- * Name of the state this handler calls about, used in try-and-slice matching.
- */
- const char *state_name;
- /**
- * Function to call whenever the respective state changes.
- */
- GNUNET_PSYC_StateCallback event_handler;
+/**
+ * Request to replay the latest messages from the message history of the channel.
+ *
+ * Historic messages (but NOT the state at the time) will be replayed (given to
+ * the normal method handlers) if available and if access is permitted.
+ *
+ * @param channel
+ * Which channel should be replayed?
+ * @param message_limit
+ * Maximum number of messages to replay.
+ * @param flags
+ * OR'ed enum GNUNET_PSYC_HistoryReplayFlags
+ * @param finish_cb
+ * Function to call when the requested history has been fully replayed
+ * (counting message IDs might not suffice, as some messages might be
+ * secret and thus the listener would not know the story is finished
+ * without being told explicitly)o once this function has been called, the
+ * client must not call GNUNET_PSYC_channel_history_replay_cancel() anymore.
+ * @param cls
+ * Closure for the callbacks.
+ *
+ * @return Handle to cancel history replay operation.
+ */
+struct GNUNET_PSYC_HistoryRequest *
+GNUNET_PSYC_channel_history_replay_latest (struct GNUNET_PSYC_Channel *channel,
+ uint64_t message_limit,
+ const char *method_prefix,
+ uint32_t flags,
+ GNUNET_PSYC_MessageCallback message_cb,
+ GNUNET_PSYC_MessagePartCallback message_part_cb,
+ GNUNET_ResultCallback result_cb,
+ void *cls);
- /**
- * Closure for the 'event_handler' function.
- */
- void *event_handler_cls;
- /**
- * Description of the kind of state that the handler expects to see.
- * Non-matching state updates will be ignored (but logged). Note
- * that the state_types of all states with the same state name prefix
- * should be identical.
- */
- struct GNUNET_PSYC_ArgumentDescriptor state_type;
+void
+GNUNET_PSYC_channel_history_replay_cancel (struct GNUNET_PSYC_Channel *channel,
+ struct GNUNET_PSYC_HistoryRequest *hr);
-};
+
+/**
+ * Function called to inform a member about stored state values for a channel.
+ *
+ * If @a full_value_size > value_size then this function is called multiple
+ * times until the whole value arrived.
+ *
+ * @param cls
+ * Closure.
+ * @param name
+ * Name of the state variable.
+ * NULL if there are no more state variables to be returned.
+ * @param value
+ * Value of the state variable.
+ * @param value_size
+ * Number of bytes in @a value.
+ * @param full_value_size
+ * Number of bytes in the full value, including continuations.
+ * Only set for the first part of a variable,
+ * in case of a continuation it is 0.
+ */
+typedef void
+(*GNUNET_PSYC_StateVarCallback) (void *cls,
+ const struct GNUNET_MessageHeader *mod,
+ const char *name,
+ const void *value,
+ uint32_t value_size,
+ uint32_t full_value_size);
/**
- * Join a psyc group. The entity joining is always the local peer.
- * This will send a 'join_msg' to the origin; if it succeeds, the
- * channel state will be replayed to the joining member and the 'join'
- * method will be invoked to show that we joined successfully. There
- * is no explicit notification on failure (as the origin may simply
- * take days to approve, and disapproval is simply being ignored).
- *
- * Note that we also specify the message to transmit to origin on
- * 'leave' here, as a sudden crash might otherwise not permit sending
- * a 'nice' leave message. TODO: we might want an API to change
- * the 'leave' message later during the session.
- *
- * @param cfg configuration to use
- * @param pub_key ECC key that identifies the group
- * @param method_count number of methods in 'methods' array
- * @param methods functions to invoke on messages received from the origin,
- * typcially at least contains functions for 'join' and 'leave'.
- * @param state_count number of state handlers
- * @param state_handlers array of state event handlers
- * @param join_data method to invoke on origin to trigger joining;
- * use NULL to send nothing (useful for anonymous groups that permit anyone);
- arguments to give to join method, must not include streaming args
- * @param leave_data method to invoke on origin on leaving;
- * use NULL to send nothing (useful for anonymous groups that permit anyone);
- arguments to give to leave method, must not include streaming args
- * @return handle for the member, NULL on error
- */
-struct GNUNET_PSYC_Member *
-GNUNET_PSYC_member_join (const struct GNUNET_CONFIGURATION_Handle *cfg,
- const struct GNUNET_CRYPTO_EccPublicKey *pub_key,
- unsigned int method_count,
- const struct GNUNET_PSYC_MethodDescriptor *methods,
- unsigned int state_count,
- struct GNUNET_PSYC_StateHandler *state_handlers,
- const struct GNUNET_PSYC_CallData *join_data,
- const struct GNUNET_PSYC_CallData *leave_data);
-
-
-/**
- * Request a message to be send to the origin.
- *
- * @param member membership handle
- * @param request_data which method should be invoked on origin (and how)
- *
- * FIXME: change to notify_transmit_ready-style to wait for ACKs
- * and to enable streaming arguments!
+ * State request handle.
*/
-void
-GNUNET_PSYC_member_send_to_origin (struct GNUNET_PSYC_Member *member,
- const struct GNUNET_PSYC_CallData *request_data);
+struct GNUNET_PSYC_StateRequest;
/**
- * Call the given state callback on all matching states in the channel
- * state. The callback is invoked synchronously on all matching
- * states (as the state is fully replicated in the library in this
- * process; channel states should be small, large data is to be passed
- * as streaming data to methods).
+ * Retrieve the best matching channel state variable.
+ *
+ * If the requested variable name is not present in the state, the nearest
+ * less-specific name is matched; for example, requesting "_a_b" will match "_a"
+ * if "_a_b" does not exist.
*
- * @param member membership handle
- * @param state_name name of the state to query (full name
- * might be longer, this is only the prefix that must match)
- * @param cb function to call on the matching state values
- * @param cb_cls closure for 'cb'
+ * @param channel
+ * Channel handle.
+ * @param full_name
+ * Full name of the requested variable.
+ * The actual variable returned might have a shorter name.
+ * @param var_cb
+ * Function called once when a matching state variable is found.
+ * Not called if there's no matching state variable.
+ * @param result_cb
+ * Function called after the operation finished.
+ * (i.e. all state variables have been returned via @a state_cb)
+ * @param cls
+ * Closure for the callbacks.
*/
-int
-GNUNET_PSYC_member_state_get (struct GNUNET_PSYC_Member *member,
- const char *state_name,
- GNUNET_PSYC_StateCallback cb,
- void *cb_cls);
+struct GNUNET_PSYC_StateRequest *
+GNUNET_PSYC_channel_state_get (struct GNUNET_PSYC_Channel *channel,
+ const char *full_name,
+ GNUNET_PSYC_StateVarCallback var_cb,
+ GNUNET_ResultCallback result_cb,
+ void *cls);
/**
- * Leave a mutlicast group. Will terminate the connection to the PSYC
- * service, which will send the 'leave' method that was prepared
- * earlier to the origin. This function must not be called on a
- * 'member' that was obtained from GNUNET_PSYC_origin_get_group.
+ * Return all channel state variables whose name matches a given prefix.
+ *
+ * A name matches if it starts with the given @a name_prefix, thus requesting
+ * the empty prefix ("") will match all values; requesting "_a_b" will also
+ * return values stored under "_a_b_c".
+ *
+ * The @a state_cb is invoked on all matching state variables asynchronously, as
+ * the state is stored in and retrieved from the PSYCstore,
+ *
+ * @param channel
+ * Channel handle.
+ * @param name_prefix
+ * Prefix of the state variable name to match.
+ * @param var_cb
+ * Function called once when a matching state variable is found.
+ * Not called if there's no matching state variable.
+ * @param result_cb
+ * Function called after the operation finished.
+ * (i.e. all state variables have been returned via @a state_cb)
+ * @param cls
+ * Closure for the callbacks.
+ */
+struct GNUNET_PSYC_StateRequest *
+GNUNET_PSYC_channel_state_get_prefix (struct GNUNET_PSYC_Channel *channel,
+ const char *name_prefix,
+ GNUNET_PSYC_StateVarCallback var_cb,
+ GNUNET_ResultCallback result_cb,
+ void *cls);
+
+/**
+ * Cancel a state request operation.
*
- * @param member membership handle
+ * @param sr
+ * Handle for the operation to cancel.
*/
void
-GNUNET_PSYC_member_leave (struct GNUNET_PSYC_Member *member);
+GNUNET_PSYC_channel_state_get_cancel (struct GNUNET_PSYC_StateRequest *sr);
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