X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=src%2Fpeerinfo%2Fpeerinfo_api.c;h=a0cb5c5c4a94323aba029ffcdb1d79393d0e6006;hb=320c2d50b722eeffc50cd6db0c5361886ee750b0;hp=5531ede977d8425fa3e8f000ef7b10c8d8ee0d7e;hpb=98ea57dd2236542414e52792672d8563c8ca4294;p=oweals%2Fgnunet.git diff --git a/src/peerinfo/peerinfo_api.c b/src/peerinfo/peerinfo_api.c index 5531ede97..a0cb5c5c4 100644 --- a/src/peerinfo/peerinfo_api.c +++ b/src/peerinfo/peerinfo_api.c @@ -1,10 +1,10 @@ /* This file is part of GNUnet. - (C) 2001, 2002, 2004, 2005, 2007, 2009 Christian Grothoff (and other contributing authors) + (C) 2001, 2002, 2004, 2005, 2007, 2009, 2010 Christian Grothoff (and other contributing authors) GNUnet is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published - by the Free Software Foundation; either version 2, or (at your + by the Free Software Foundation; either version 3, or (at your option) any later version. GNUnet is distributed in the hope that it will be useful, but @@ -25,390 +25,391 @@ */ #include "platform.h" #include "gnunet_client_lib.h" +#include "gnunet_container_lib.h" #include "gnunet_peerinfo_service.h" #include "gnunet_protocols.h" #include "gnunet_time_lib.h" #include "peerinfo.h" -#define ADD_PEER_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 30) - - -struct CAFContext -{ - struct GNUNET_CLIENT_Connection *client; - struct GNUNET_MessageHeader *msg; -}; +/** + * Function to call after transmission has succeeded. + * + * @param cls closure + * @param success GNUNET_OK if transmission worked, GNUNET_SYSERR on error + */ +typedef void (*TransmissionContinuation)(void *cls, + int success); -static size_t -copy_and_free (void *cls, size_t size, void *buf) +/** + * Entry in the transmission queue to PEERINFO service. + */ +struct TransmissionQueueEntry { - struct CAFContext *cc = cls; - struct GNUNET_MessageHeader *msg = cc->msg; - uint16_t msize; - - if (buf == NULL) - { -#if DEBUG_PEERINFO - GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, - _ - ("Failed to transmit message of type %u to `%s' service.\n"), - ntohs (msg->type), "peerinfo"); -#endif - GNUNET_free (msg); - GNUNET_CLIENT_disconnect (cc->client); - GNUNET_free (cc); - return 0; - } - msize = ntohs (msg->size); - GNUNET_assert (size >= msize); - memcpy (buf, msg, msize); - GNUNET_free (msg); - GNUNET_CLIENT_disconnect (cc->client); - GNUNET_free (cc); - return msize; -} + /** + * This is a linked list. + */ + struct TransmissionQueueEntry *next; + + /** + * This is a linked list. + */ + struct TransmissionQueueEntry *prev; + /** + * Function to call after request has been transmitted, or NULL (in which + * case we must consider sending the next entry immediately). + */ + TransmissionContinuation cont; + + /** + * Closure for 'cont'. + */ + void *cont_cls; + /** + * Timeout for the operation. + */ + struct GNUNET_TIME_Absolute timeout; -/** - * Add a host to the persistent list. - * - * @param cfg configuration to use - * @param sched scheduler to use - * @param peer identity of the peer - * @param hello the verified (!) HELLO message - */ -void -GNUNET_PEERINFO_add_peer (const struct GNUNET_CONFIGURATION_Handle *cfg, - struct GNUNET_SCHEDULER_Handle *sched, - const struct GNUNET_PeerIdentity *peer, - const struct GNUNET_HELLO_Message *hello) -{ - struct GNUNET_CLIENT_Connection *client; - struct PeerAddMessage *pam; - uint16_t hs; - struct CAFContext *cc; + /** + * Number of bytes of the request message (follows after this struct). + */ + size_t size; -#if DEBUG_PEERINFO - GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, - "Adding peer `%s' to peerinfo database\n", - GNUNET_i2s(peer)); -#endif - client = GNUNET_CLIENT_connect (sched, "peerinfo", cfg); - if (client == NULL) - { - GNUNET_log (GNUNET_ERROR_TYPE_WARNING, - _("Could not connect to `%s' service.\n"), "peerinfo"); - return; - } - hs = GNUNET_HELLO_size (hello); -#if DEBUG_PEERINFO - GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, - "Size of `%s' is %u bytes\n", - "HELLO", - (unsigned int) GNUNET_HELLO_size (hello)); -#endif - pam = GNUNET_malloc (sizeof (struct PeerAddMessage) + hs); - pam->header.size = htons (hs + sizeof (struct PeerAddMessage)); - pam->header.type = htons (GNUNET_MESSAGE_TYPE_PEERINFO_ADD); - memcpy (&pam->peer, peer, sizeof (struct GNUNET_PeerIdentity)); - memcpy (&pam[1], hello, hs); - cc = GNUNET_malloc (sizeof (struct CAFContext)); - cc->client = client; - cc->msg = &pam->header; - GNUNET_CLIENT_notify_transmit_ready (client, - ntohs (pam->header.size), - ADD_PEER_TIMEOUT, - GNUNET_NO, - ©_and_free, cc); -} +}; /** - * Context for the info handler. + * Handle to the peerinfo service. */ -struct GNUNET_PEERINFO_IteratorContext +struct GNUNET_PEERINFO_Handle { + /** + * Our configuration. + */ + const struct GNUNET_CONFIGURATION_Handle *cfg; /** - * Our connection to the PEERINFO service. + * Connection to the service. */ struct GNUNET_CLIENT_Connection *client; /** - * Function to call with information. + * Head of transmission queue. */ - GNUNET_PEERINFO_Processor callback; + struct TransmissionQueueEntry *tq_head; /** - * Closure for callback. + * Tail of transmission queue. */ - void *callback_cls; + struct TransmissionQueueEntry *tq_tail; /** - * When should we time out? + * Handle for the current transmission request, or NULL if none is pending. */ - struct GNUNET_TIME_Absolute timeout; + struct GNUNET_CLIENT_TransmitHandle *th; + + /** + * Set to GNUNET_YES if we are currently receiving replies from the + * service. + */ + int in_receive; }; /** - * Type of a function to call when we receive a message - * from the service. + * Connect to the peerinfo service. * - * @param cls closure - * @param msg message received, NULL on timeout or fatal error + * @param cfg configuration to use + * @return NULL on error (configuration related, actual connection + * establishment may happen asynchronously). */ -static void -info_handler (void *cls, const struct GNUNET_MessageHeader *msg) +struct GNUNET_PEERINFO_Handle * +GNUNET_PEERINFO_connect (const struct GNUNET_CONFIGURATION_Handle *cfg) { - struct GNUNET_PEERINFO_IteratorContext *ic = cls; - const struct InfoMessage *im; - const struct GNUNET_HELLO_Message *hello; - uint16_t ms; + struct GNUNET_CLIENT_Connection *client; + struct GNUNET_PEERINFO_Handle *ret; - if (msg == NULL) - { - GNUNET_log (GNUNET_ERROR_TYPE_WARNING, - _("Failed to receive response from `%s' service.\n"), - "peerinfo"); - ic->callback (ic->callback_cls, NULL, NULL, 1); - GNUNET_CLIENT_disconnect (ic->client); - GNUNET_free (ic); - return; - } - if (ntohs (msg->type) == GNUNET_MESSAGE_TYPE_PEERINFO_INFO_END) - { -#if DEBUG_PEERINFO - GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, - "Received end of list of peers from peerinfo database\n"); -#endif - ic->callback (ic->callback_cls, NULL, NULL, 0); - GNUNET_CLIENT_disconnect (ic->client); - GNUNET_free (ic); - return; - } - ms = ntohs (msg->size); - if ((ms < sizeof (struct InfoMessage)) || - (ntohs (msg->type) != GNUNET_MESSAGE_TYPE_PEERINFO_INFO)) - { - GNUNET_break (0); - ic->callback (ic->callback_cls, NULL, NULL, 2); - GNUNET_CLIENT_disconnect (ic->client); - GNUNET_free (ic); - return; + client = GNUNET_CLIENT_connect ("peerinfo", cfg); + if (client == NULL) + return NULL; + ret = GNUNET_malloc (sizeof (struct GNUNET_PEERINFO_Handle)); + ret->client = client; + ret->cfg = cfg; + return ret; +} + + +/** + * Disconnect from the peerinfo service. Note that all iterators must + * have completed or have been cancelled by the time this function is + * called (otherwise, calling this function is a serious error). + * Furthermore, if 'GNUNET_PEERINFO_add_peer' operations are still + * pending, they will be cancelled silently on disconnect. + * + * @param h handle to disconnect + */ +void +GNUNET_PEERINFO_disconnect (struct GNUNET_PEERINFO_Handle *h) +{ + struct TransmissionQueueEntry *tqe; + + while (NULL != (tqe = h->tq_head)) + { + GNUNET_CONTAINER_DLL_remove (h->tq_head, + h->tq_tail, + tqe); + if (tqe->cont != NULL) + tqe->cont (tqe->cont_cls, GNUNET_SYSERR); + GNUNET_free (tqe); } - im = (const struct InfoMessage *) msg; - hello = NULL; - if (ms > sizeof (struct InfoMessage) + sizeof (struct GNUNET_MessageHeader)) + if (h->th != NULL) { - hello = (const struct GNUNET_HELLO_Message *) &im[1]; - if (ms != sizeof (struct InfoMessage) + GNUNET_HELLO_size (hello)) - { - GNUNET_break (0); - ic->callback (ic->callback_cls, NULL, NULL, 2); - GNUNET_CLIENT_disconnect (ic->client); - GNUNET_free (ic); - return; - } + GNUNET_CLIENT_notify_transmit_ready_cancel (h->th); + h->th = NULL; } -#if DEBUG_PEERINFO - GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, - "Received information about peer `%s' from peerinfo database\n", - GNUNET_i2s (&im->peer)); -#endif -#if DEBUG_PEERINFO - GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, - "Size of `%s' is %u bytes\n", - "HELLO", - (hello == NULL) ? 0 : (unsigned int) GNUNET_HELLO_size (hello)); -#endif - ic->callback (ic->callback_cls, &im->peer, hello, ntohl (im->trust)); - GNUNET_CLIENT_receive (ic->client, - &info_handler, - ic, - GNUNET_TIME_absolute_get_remaining (ic->timeout)); + GNUNET_CLIENT_disconnect (h->client, GNUNET_NO); + GNUNET_free (h); } /** - * Call a method for each known matching host and change - * its trust value. The method will be invoked once for - * each host and then finally once with a NULL pointer. - * Note that the last call can be triggered by timeout or - * by simply being done; however, the trust argument will - * be set to zero if we are done and to 1 if we timed out. + * Check if we have a request pending in the transmission queue and are + * able to transmit it right now. If so, schedule transmission. * - * @param cfg configuration to use - * @param sched scheduler to use - * @param peer restrict iteration to this peer only (can be NULL) - * @param trust_delta how much to change the trust in all matching peers - * @param timeout how long to wait until timing out - * @param callback the method to call for each peer - * @param callback_cls closure for callback - * @return NULL on error, otherwise an iterator context + * @param h handle to the service */ -struct GNUNET_PEERINFO_IteratorContext * -GNUNET_PEERINFO_iterate (const struct GNUNET_CONFIGURATION_Handle *cfg, - struct GNUNET_SCHEDULER_Handle *sched, - const struct GNUNET_PeerIdentity *peer, - int trust_delta, - struct GNUNET_TIME_Relative timeout, - GNUNET_PEERINFO_Processor callback, - void *callback_cls) +static void +trigger_transmit (struct GNUNET_PEERINFO_Handle *h); + + +/** + * Close the existing connection to PEERINFO and reconnect. + * + * @param h handle to the service + */ +static void +reconnect (struct GNUNET_PEERINFO_Handle *h) { - struct GNUNET_CLIENT_Connection *client; - struct ListAllPeersMessage *lapm; - struct ListPeerMessage *lpm; - struct GNUNET_PEERINFO_IteratorContext *ihc; + GNUNET_CLIENT_disconnect (h->client, GNUNET_SYSERR); + h->th = NULL; + h->client = GNUNET_CLIENT_connect ("peerinfo", h->cfg); + GNUNET_assert (h->client != NULL); +} - client = GNUNET_CLIENT_connect (sched, "peerinfo", cfg); - if (client == NULL) + +/** + * Transmit the request at the head of the transmission queue + * and trigger continuation (if any). + * + * @param cls the 'struct GNUNET_PEERINFO_Handle' (with the queue) + * @param size size of the buffer (0 on error) + * @param buf where to copy the message + * @return number of bytes copied to buf + */ +static size_t +do_transmit (void *cls, size_t size, void *buf) +{ + struct GNUNET_PEERINFO_Handle *h = cls; + struct TransmissionQueueEntry *tqe = h->tq_head; + size_t ret; + + h->th = NULL; + if (buf == NULL) { - GNUNET_log (GNUNET_ERROR_TYPE_WARNING, - _("Could not connect to `%s' service.\n"), "peerinfo"); - return NULL; + GNUNET_log (GNUNET_ERROR_TYPE_WARNING | GNUNET_ERROR_TYPE_BULK, + _("Failed to transmit message to `%s' service.\n"), + "PEERINFO"); + if (tqe != NULL) + GNUNET_CONTAINER_DLL_remove (h->tq_head, + h->tq_tail, + tqe); + reconnect (h); + trigger_transmit (h); + if (tqe != NULL) + { + if (tqe->cont != NULL) + tqe->cont (tqe->cont_cls, GNUNET_SYSERR); + GNUNET_free (tqe); + } + return 0; } + /* If it can be NULL above, it can be NULL here to... */ + if (tqe == NULL) + return 0; + + ret = tqe->size; + GNUNET_assert (size >= ret); + memcpy (buf, &tqe[1], ret); #if DEBUG_PEERINFO GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, - "Requesting list of peers from peerinfo database\n"); + "Transmitting request of size %u to `%s' service.\n", + ret, + "PEERINFO"); #endif - if (peer == NULL) - { - ihc = GNUNET_malloc (sizeof (struct GNUNET_PEERINFO_IteratorContext) + - sizeof (struct ListAllPeersMessage)); - lapm = (struct ListAllPeersMessage *) &ihc[1]; - lapm->header.size = htons (sizeof (struct ListAllPeersMessage)); - lapm->header.type = htons (GNUNET_MESSAGE_TYPE_PEERINFO_GET_ALL); - lapm->trust_change = htonl (trust_delta); - } + GNUNET_CONTAINER_DLL_remove (h->tq_head, + h->tq_tail, + tqe); + if (tqe->cont != NULL) + tqe->cont (tqe->cont_cls, GNUNET_OK); else - { - ihc = GNUNET_malloc (sizeof (struct GNUNET_PEERINFO_IteratorContext) + - sizeof (struct ListPeerMessage)); - lpm = (struct ListPeerMessage *) &ihc[1]; - lpm->header.size = htons (sizeof (struct ListPeerMessage)); - lpm->header.type = htons (GNUNET_MESSAGE_TYPE_PEERINFO_GET); - lpm->trust_change = htonl (trust_delta); - memcpy (&lpm->peer, peer, sizeof (struct GNUNET_PeerIdentity)); - } - ihc->client = client; - ihc->callback = callback; - ihc->callback_cls = callback_cls; - ihc->timeout = GNUNET_TIME_relative_to_absolute (timeout); - if (GNUNET_OK != - GNUNET_CLIENT_transmit_and_get_response (client, - (const struct GNUNET_MessageHeader*) &ihc[1], - timeout, + trigger_transmit (h); + GNUNET_free (tqe); + return ret; +} + + +/** + * Check if we have a request pending in the transmission queue and are + * able to transmit it right now. If so, schedule transmission. + * + * @param h handle to the service + */ +static void +trigger_transmit (struct GNUNET_PEERINFO_Handle *h) +{ + struct TransmissionQueueEntry *tqe; + + if (NULL == (tqe = h->tq_head)) + return NULL; + if (h->th != NULL) + return NULL; + if (h->in_receive == GNUNET_YES) + return NULL; + h->th = GNUNET_CLIENT_notify_transmit_ready (h->client, + tqe->size, + GNUNET_TIME_absolute_get_remaining (tqe->timeout), GNUNET_YES, - &info_handler, - ihc)) - { - GNUNET_break (0); - GNUNET_CLIENT_disconnect (ihc->client); - GNUNET_free (ihc); - return NULL; - } - return ihc; + &do_transmit, h); } /** - * Cancel an iteration over peer information. + * Add a host to the persistent list. This method operates in + * semi-reliable mode: if the transmission is not completed by + * the time 'GNUNET_PEERINFO_disconnect' is called, it will be + * aborted. Furthermore, if a second HELLO is added for the + * same peer before the first one was transmitted, PEERINFO may + * merge the two HELLOs prior to transmission to the service. * - * @param ic context of the iterator to cancel + * @param h handle to the peerinfo service + * @param hello the verified (!) HELLO message */ void -GNUNET_PEERINFO_iterate_cancel (struct GNUNET_PEERINFO_IteratorContext *ic) +GNUNET_PEERINFO_add_peer (struct GNUNET_PEERINFO_Handle *h, + const struct GNUNET_HELLO_Message *hello) { - GNUNET_CLIENT_disconnect (ic->client); - GNUNET_free (ic); + uint16_t hs = GNUNET_HELLO_size (hello); + struct TransmissionQueueEntry *tqe; + +#if DEBUG_PEERINFO + struct GNUNET_PeerIdentity peer; + GNUNET_assert (GNUNET_OK == GNUNET_HELLO_get_id (hello, &peer)); + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Adding peer `%s' to PEERINFO database (%u bytes of `%s')\n", + GNUNET_i2s(&peer), + hs, + "HELLO"); +#endif + tqe = GNUNET_malloc (sizeof (struct TransmissionQueueEntry) + hs); + tqe->size = hs; + tqe->timeout = GNUNET_TIME_UNIT_FOREVER_ABS; + memcpy (&tqe[1], hello, hs); + GNUNET_CONTAINER_DLL_insert_after (h->tq_head, + h->tq_tail, + h->tq_tail, + tqe); + trigger_transmit (h); } /** - * Context for the info handler. + * Context for an iteration request. */ -struct GNUNET_PEERINFO_NotifyContext +struct GNUNET_PEERINFO_IteratorContext { - /** - * Our connection to the PEERINFO service. + * Handle to the PEERINFO service. */ - struct GNUNET_CLIENT_Connection *client; + struct GNUNET_PEERINFO_Handle *h; /** - * Function to call with information. + * Function to call with the results. */ GNUNET_PEERINFO_Processor callback; /** - * Closure for callback. + * Closure for 'callback'. */ void *callback_cls; /** - * Handle to our initial request for message transmission to - * the peerinfo service. + * Our entry in the transmission queue. */ - struct GNUNET_CLIENT_TransmitHandle *init; + struct TransmissionQueueEntry *tqe; /** - * Configuration. + * Task responsible for timeout. */ - const struct GNUNET_CONFIGURATION_Handle *cfg; + GNUNET_SCHEDULER_TaskIdentifier timeout_task; /** - * Scheduler. + * Timeout for the operation. */ - struct GNUNET_SCHEDULER_Handle *sched; -}; - - -/** - * Send a request to the peerinfo service to start being - * notified about all changes to peer information. - * - * @param nc our context - */ -static void -request_notifications (struct GNUNET_PEERINFO_NotifyContext *nc); - + struct GNUNET_TIME_Absolute timeout; -/** - * Read notifications from the client handle and pass them - * to the callback. - * - * @param nc our context - */ -static void -receive_notifications (struct GNUNET_PEERINFO_NotifyContext *nc); + /** + * Are we now receiving? + */ + int in_receive; +}; /** - * Receive a peerinfo information message, process it and - * go for more. + * Type of a function to call when we receive a message + * from the service. * * @param cls closure * @param msg message received, NULL on timeout or fatal error */ static void -process_notification (void *cls, - const struct - GNUNET_MessageHeader * msg) +peerinfo_handler (void *cls, const struct GNUNET_MessageHeader *msg) { - struct GNUNET_PEERINFO_NotifyContext *nc = cls; + struct GNUNET_PEERINFO_IteratorContext *ic = cls; const struct InfoMessage *im; const struct GNUNET_HELLO_Message *hello; uint16_t ms; + ic->h->in_receive = GNUNET_NO; if (msg == NULL) { - GNUNET_CLIENT_disconnect (nc->client); - nc->client = GNUNET_CLIENT_connect (nc->sched, "peerinfo", nc->cfg); - request_notifications (nc); + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + _("Failed to receive response from `%s' service.\n"), + "PEERINFO"); + reconnect (ic->h); + trigger_transmit (ic->h); + if (ic->timeout_task != GNUNET_SCHEDULER_NO_TASK) + GNUNET_SCHEDULER_cancel (ic->timeout_task); + if (ic->callback != NULL) + ic->callback (ic->callback_cls, NULL, NULL); + GNUNET_free (ic); + return; + } + if (ntohs (msg->type) == GNUNET_MESSAGE_TYPE_PEERINFO_INFO_END) + { +#if DEBUG_PEERINFO + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Received end of list of peers from `%s' service\n", + "PEERINFO"); +#endif + trigger_transmit (ic->h); + if (ic->timeout_task != GNUNET_SCHEDULER_NO_TASK) + GNUNET_SCHEDULER_cancel (ic->timeout_task); + if (ic->callback != NULL) + ic->callback (ic->callback_cls, NULL, NULL); + GNUNET_free (ic); return; } ms = ntohs (msg->size); @@ -416,156 +417,226 @@ process_notification (void *cls, (ntohs (msg->type) != GNUNET_MESSAGE_TYPE_PEERINFO_INFO)) { GNUNET_break (0); - GNUNET_CLIENT_disconnect (nc->client); - nc->client = GNUNET_CLIENT_connect (nc->sched, "peerinfo", nc->cfg); - request_notifications (nc); + reconnect (ic->h); + trigger_transmit (ic->h); + if (ic->timeout_task != GNUNET_SCHEDULER_NO_TASK) + GNUNET_SCHEDULER_cancel (ic->timeout_task); + if (ic->callback != NULL) + ic->callback (ic->callback_cls, NULL, NULL); + GNUNET_free (ic); return; } im = (const struct InfoMessage *) msg; + GNUNET_break (0 == ntohl (im->reserved)); hello = NULL; if (ms > sizeof (struct InfoMessage) + sizeof (struct GNUNET_MessageHeader)) { hello = (const struct GNUNET_HELLO_Message *) &im[1]; if (ms != sizeof (struct InfoMessage) + GNUNET_HELLO_size (hello)) { - GNUNET_break (0); - GNUNET_CLIENT_disconnect (nc->client); - nc->client = GNUNET_CLIENT_connect (nc->sched, "peerinfo", nc->cfg); - request_notifications (nc); + GNUNET_break (0); + reconnect (ic->h); + trigger_transmit (ic->h); + if (ic->timeout_task != GNUNET_SCHEDULER_NO_TASK) + GNUNET_SCHEDULER_cancel (ic->timeout_task); + if (ic->callback != NULL) + ic->callback (ic->callback_cls, NULL, NULL); + GNUNET_free (ic); return; } } #if DEBUG_PEERINFO GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, - "Received information about peer `%s' from peerinfo database\n", - GNUNET_i2s (&im->peer)); + "Received %u bytes of `%s' information about peer `%s' from `%s' service\n", + (hello == NULL) ? 0 : (unsigned int) GNUNET_HELLO_size (hello), + "HELLO", + GNUNET_i2s (&im->peer), + "PEERINFO"); #endif - nc->callback (nc->callback_cls, &im->peer, hello, ntohl (im->trust)); - receive_notifications (nc); + ic->h->in_receive = GNUNET_YES; + if (ic->callback != NULL) + ic->callback (ic->callback_cls, &im->peer, hello); + GNUNET_CLIENT_receive (ic->h->client, + &peerinfo_handler, + ic, + GNUNET_TIME_absolute_get_remaining (ic->timeout)); } /** - * Read notifications from the client handle and pass them - * to the callback. + * We've transmitted the iteration request. Now get ready to process + * the results (or handle transmission error). * - * @param nc our context + * @param cls the 'struct GNUNET_PEERINFO_IteratorContext' + * @param transmit_success GNUNET_OK if transmission worked */ static void -receive_notifications (struct GNUNET_PEERINFO_NotifyContext *nc) +iterator_start_receive (void *cls, + int transmit_success) { - GNUNET_CLIENT_receive (nc->client, - &process_notification, - nc, - GNUNET_TIME_UNIT_FOREVER_REL); -} - - -/** - * Transmit our init-notify request, start receiving. - * - * @param cls closure (our 'struct GNUNET_PEERINFO_NotifyContext') - * @param size number of bytes available in buf - * @param buf where the callee should write the message - * @return number of bytes written to buf - */ -static size_t -transmit_notify_request (void *cls, - size_t size, - void *buf) -{ - struct GNUNET_PEERINFO_NotifyContext *nc = cls; - struct GNUNET_MessageHeader hdr; + struct GNUNET_PEERINFO_IteratorContext *ic = cls; - nc->init = NULL; - if (buf == NULL) + if (GNUNET_OK != transmit_success) { - GNUNET_CLIENT_disconnect (nc->client); - nc->client = GNUNET_CLIENT_connect (nc->sched, "peerinfo", nc->cfg); - request_notifications (nc); - return 0; - } - GNUNET_assert (size >= sizeof (struct GNUNET_MessageHeader)); - hdr.size = htons (sizeof (struct GNUNET_MessageHeader)); - hdr.type = htons (GNUNET_MESSAGE_TYPE_PEERINFO_NOTIFY); - memcpy (buf, &hdr, sizeof (struct GNUNET_MessageHeader)); - receive_notifications (nc); - return sizeof (struct GNUNET_MessageHeader); + GNUNET_log (GNUNET_ERROR_TYPE_WARNING, + _("Failed to transmit iteration request to `%s' service (%d).\n"), + "PEERINFO", + transmit_success); + if (ic->timeout_task != GNUNET_SCHEDULER_NO_TASK) + { + GNUNET_SCHEDULER_cancel (ic->timeout_task); + ic->timeout_task = GNUNET_SCHEDULER_NO_TASK; + } + reconnect (ic->h); + trigger_transmit (ic->h); + if (ic->callback != NULL) + ic->callback (ic->callback_cls, NULL, NULL); + GNUNET_free (ic); + return; + } +#if DEBUG_PEERINFO + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Waiting for response from `%s' service.\n", + "PEERINFO"); +#endif + ic->h->in_receive = GNUNET_YES; + ic->in_receive = GNUNET_YES; + ic->tqe = NULL; + GNUNET_CLIENT_receive (ic->h->client, + &peerinfo_handler, + ic, + GNUNET_TIME_absolute_get_remaining (ic->timeout)); } /** - * Send a request to the peerinfo service to start being - * notified about all changes to peer information. + * Peerinfo iteration request has timed out. * - * @param nc our context + * @param cls the 'struct GNUNET_PEERINFO_IteratorContext*' + * @param tc scheduler context */ static void -request_notifications (struct GNUNET_PEERINFO_NotifyContext *nc) +signal_timeout (void *cls, + const struct GNUNET_SCHEDULER_TaskContext *tc) { - GNUNET_assert (NULL == nc->init); - nc->init =GNUNET_CLIENT_notify_transmit_ready (nc->client, - sizeof (struct GNUNET_MessageHeader), - GNUNET_TIME_UNIT_FOREVER_REL, - GNUNET_YES, - &transmit_notify_request, - nc); + struct GNUNET_PEERINFO_IteratorContext *ic = cls; + + GNUNET_log (GNUNET_ERROR_TYPE_WARNING | GNUNET_ERROR_TYPE_BULK, + _("Timeout transmitting iteration request to `%s' service.\n"), + "PEERINFO"); + ic->timeout_task = GNUNET_SCHEDULER_NO_TASK; + if (! ic->in_receive) + GNUNET_CONTAINER_DLL_remove (ic->h->tq_head, + ic->h->tq_tail, + ic->tqe); + reconnect (ic->h); + ic->callback (ic->callback_cls, NULL, NULL); + ic->callback = NULL; + GNUNET_free_non_null (ic->tqe); + GNUNET_free (ic); } /** - * Call a method whenever our known information about peers - * changes. Initially calls the given function for all known - * peers and then only signals changes. + * Call a method for each known matching host and change its trust + * value. The callback method will be invoked once for each matching + * host and then finally once with a NULL pointer. After that final + * invocation, the iterator context must no longer be used. * - * @param cfg configuration to use - * @param sched scheduler to use + * Instead of calling this function with 'peer == NULL' it is often + * better to use 'GNUNET_PEERINFO_notify'. + * + * @param h handle to the peerinfo service + * @param peer restrict iteration to this peer only (can be NULL) + * @param timeout how long to wait until timing out * @param callback the method to call for each peer * @param callback_cls closure for callback - * @return NULL on error + * @return iterator context */ -struct GNUNET_PEERINFO_NotifyContext * -GNUNET_PEERINFO_notify (const struct GNUNET_CONFIGURATION_Handle *cfg, - struct GNUNET_SCHEDULER_Handle *sched, - GNUNET_PEERINFO_Processor callback, - void *callback_cls) +struct GNUNET_PEERINFO_IteratorContext * +GNUNET_PEERINFO_iterate (struct GNUNET_PEERINFO_Handle *h, + const struct GNUNET_PeerIdentity *peer, + struct GNUNET_TIME_Relative timeout, + GNUNET_PEERINFO_Processor callback, + void *callback_cls) { - struct GNUNET_PEERINFO_NotifyContext *nc; - struct GNUNET_CLIENT_Connection *client; + struct GNUNET_MessageHeader *lapm; + struct ListPeerMessage *lpm; + struct GNUNET_PEERINFO_IteratorContext *ic; + struct TransmissionQueueEntry *tqe; - client = GNUNET_CLIENT_connect (sched, "peerinfo", cfg); - if (client == NULL) - { - GNUNET_log (GNUNET_ERROR_TYPE_WARNING, - _("Could not connect to `%s' service.\n"), "peerinfo"); - return NULL; + if (peer == NULL) + { +#if DEBUG_PEERINFO + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Requesting list of peers from PEERINFO service\n"); +#endif + tqe = GNUNET_malloc (sizeof (struct TransmissionQueueEntry) + + sizeof (struct GNUNET_MessageHeader)); + tqe->size = sizeof (struct GNUNET_MessageHeader); + lapm = (struct GNUNET_MessageHeader *) &tqe[1]; + lapm->size = htons (sizeof (struct GNUNET_MessageHeader)); + lapm->type = htons (GNUNET_MESSAGE_TYPE_PEERINFO_GET_ALL); + } + else + { +#if DEBUG_PEERINFO + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Requesting information on peer `%4s' from PEERINFO service\n", + GNUNET_i2s (peer)); +#endif + tqe = GNUNET_malloc (sizeof (struct TransmissionQueueEntry) + + sizeof (struct ListPeerMessage)); + tqe->size = sizeof (struct ListPeerMessage); + lpm = (struct ListPeerMessage *) &tqe[1]; + lpm->header.size = htons (sizeof (struct ListPeerMessage)); + lpm->header.type = htons (GNUNET_MESSAGE_TYPE_PEERINFO_GET); + memcpy (&lpm->peer, peer, sizeof (struct GNUNET_PeerIdentity)); } - nc = GNUNET_malloc (sizeof (struct GNUNET_PEERINFO_NotifyContext)); - nc->sched = sched; - nc->cfg = cfg; - nc->client = client; - nc->callback = callback; - nc->callback_cls = callback_cls; - request_notifications (nc); - return nc; + ic = GNUNET_malloc (sizeof (struct GNUNET_PEERINFO_IteratorContext)); + ic->h = h; + ic->tqe = tqe; + ic->callback = callback; + ic->callback_cls = callback_cls; + ic->timeout = GNUNET_TIME_relative_to_absolute (timeout); + ic->timeout_task = GNUNET_SCHEDULER_add_delayed (timeout, + &signal_timeout, + ic); + tqe->timeout = ic->timeout; + tqe->cont = &iterator_start_receive; + tqe->cont_cls = ic; + tqe->timeout = ic->timeout; + GNUNET_CONTAINER_DLL_insert_after (h->tq_head, + h->tq_tail, + h->tq_tail, + tqe); + trigger_transmit (h); + return ic; } + /** - * Stop notifying about changes. + * Cancel an iteration over peer information. * - * @param nc context to stop notifying + * @param ic context of the iterator to cancel */ void -GNUNET_PEERINFO_notify_cancel (struct GNUNET_PEERINFO_NotifyContext *nc) +GNUNET_PEERINFO_iterate_cancel (struct GNUNET_PEERINFO_IteratorContext *ic) { - if (NULL != nc->init) + if (ic->timeout_task != GNUNET_SCHEDULER_NO_TASK) { - GNUNET_CLIENT_notify_transmit_ready_cancel (nc->init); - nc->init = NULL; + GNUNET_SCHEDULER_cancel (ic->timeout_task); + ic->timeout_task = GNUNET_SCHEDULER_NO_TASK; } - GNUNET_CLIENT_disconnect (nc->client); - GNUNET_free (nc); + ic->callback = NULL; + if (ic->in_receive) + return; /* need to finish processing */ + GNUNET_CONTAINER_DLL_remove (ic->h->tq_head, + ic->h->tq_tail, + ic->tqe); + GNUNET_free (ic->tqe); + GNUNET_free (ic); }