/* This file is part of GNUnet (C) 2004, 2005, 2006, 2007, 2009 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 option) any later version. GNUnet is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. 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. */ /** * @file datastore/gnunet-service-datastore.c * @brief Management for the datastore for files stored on a GNUnet node * @author Christian Grothoff */ #include "platform.h" #include "gnunet_util_lib.h" #include "gnunet_protocols.h" #include "plugin_datastore.h" #include "datastore.h" /** * How many messages do we queue at most per client? */ #define MAX_PENDING 1024 /** * How long are we at most keeping "expired" content * past the expiration date in the database? */ #define MAX_EXPIRE_DELAY GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 15) /** * Our datastore plugin. */ struct DatastorePlugin { /** * API of the transport as returned by the plugin's * initialization function. */ struct GNUNET_DATASTORE_PluginFunctions *api; /** * Short name for the plugin (i.e. "sqlite"). */ char *short_name; /** * Name of the library (i.e. "gnunet_plugin_datastore_sqlite"). */ char *lib_name; /** * Environment this transport service is using * for this plugin. */ struct GNUNET_DATASTORE_PluginEnvironment env; }; /** * Linked list of active reservations. */ struct ReservationList { /** * This is a linked list. */ struct ReservationList *next; /** * Client that made the reservation. */ struct GNUNET_SERVER_Client *client; /** * Number of bytes (still) reserved. */ uint64_t amount; /** * Number of items (still) reserved. */ uint64_t entries; /** * Reservation identifier. */ int32_t rid; }; /** * Our datastore plugin (NULL if not available). */ static struct DatastorePlugin *plugin; /** * Linked list of space reservations made by clients. */ static struct ReservationList *reservations; /** * Bloomfilter to quickly tell if we don't have the content. */ static struct GNUNET_CONTAINER_BloomFilter *filter; /** * Static counter to produce reservation identifiers. */ static int reservation_gen; /** * How much space are we allowed to use? */ static unsigned long long quota; /** * How much space are we using for the cache? * (space available for insertions that will be * instantly reclaimed by discarding less * important content --- or possibly whatever * we just inserted into the "cache"). */ static unsigned long long cache_size; /** * How much space have we currently reserved? */ static unsigned long long reserved; /** * Identity of the task that is used to delete * expired content. */ static GNUNET_SCHEDULER_TaskIdentifier expired_kill_task; /** * Our configuration. */ const struct GNUNET_CONFIGURATION_Handle *cfg; /** * Our scheduler. */ struct GNUNET_SCHEDULER_Handle *sched; /** * Function called once the transmit operation has * either failed or succeeded. * * @param cls closure * @param status GNUNET_OK on success, GNUNET_SYSERR on error */ typedef void (*TransmitContinuation)(void *cls, int status); struct TransmitCallbackContext { /** * The message that we're asked to transmit. */ struct GNUNET_MessageHeader *msg; /** * Client that we are transmitting to. */ struct GNUNET_SERVER_Client *client; /** * Function to call once msg has been transmitted * (or at least added to the buffer). */ TransmitContinuation tc; /** * Closure for tc. */ void *tc_cls; /** * GNUNET_YES if we are supposed to signal the server * completion of the client's request. */ int end; }; /** * Task that is used to remove expired entries from * the datastore. This task will schedule itself * again automatically to always delete all expired * content quickly. * * @param cls not used * @param tc task context */ static void delete_expired (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc); /** * Iterate over the expired items stored in the datastore. * Delete all expired items; once we have processed all * expired items, re-schedule the "delete_expired" task. * * @param cls not used * @param next_cls closure to pass to the "next" function. * @param key key for the content * @param size number of bytes in data * @param data content stored * @param type type of the content * @param priority priority of the content * @param anonymity anonymity-level for the content * @param expiration expiration time for the content * @param uid unique identifier for the datum; * maybe 0 if no unique identifier is available * * @return GNUNET_SYSERR to abort the iteration, GNUNET_OK to continue * (continue on call to "next", of course), * GNUNET_NO to delete the item and continue (if supported) */ static int expired_processor (void *cls, void *next_cls, const GNUNET_HashCode * key, uint32_t size, const void *data, uint32_t type, uint32_t priority, uint32_t anonymity, struct GNUNET_TIME_Absolute expiration, uint64_t uid) { struct GNUNET_TIME_Absolute now; expired_kill_task = GNUNET_SCHEDULER_NO_TASK; if (key == NULL) { expired_kill_task = GNUNET_SCHEDULER_add_delayed (sched, GNUNET_NO, GNUNET_SCHEDULER_PRIORITY_IDLE, GNUNET_SCHEDULER_NO_TASK, MAX_EXPIRE_DELAY, &delete_expired, NULL); return GNUNET_SYSERR; } now = GNUNET_TIME_absolute_get (); if (expiration.value > now.value) { /* finished processing */ plugin->api->next_request (next_cls, GNUNET_YES); return GNUNET_SYSERR; } plugin->api->next_request (next_cls, GNUNET_NO); #if DEBUG_DATASTORE GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Deleting content that expired %llu ms ago\n", (unsigned long long) (now.value - expiration.value)); #endif GNUNET_CONTAINER_bloomfilter_remove (filter, key); return GNUNET_NO; /* delete */ } /** * Task that is used to remove expired entries from * the datastore. This task will schedule itself * again automatically to always delete all expired * content quickly. * * @param cls not used * @param tc task context */ static void delete_expired (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { plugin->api->iter_ascending_expiration (plugin->api->cls, 0, &expired_processor, NULL); } /** * An iterator over a set of items stored in the datastore. * * @param cls closure * @param next_cls closure to pass to the "next" function. * @param key key for the content * @param size number of bytes in data * @param data content stored * @param type type of the content * @param priority priority of the content * @param anonymity anonymity-level for the content * @param expiration expiration time for the content * @param uid unique identifier for the datum; * maybe 0 if no unique identifier is available * * @return GNUNET_SYSERR to abort the iteration, GNUNET_OK to continue * (continue on call to "next", of course), * GNUNET_NO to delete the item and continue (if supported) */ static int manage (void *cls, void *next_cls, const GNUNET_HashCode * key, uint32_t size, const void *data, uint32_t type, uint32_t priority, uint32_t anonymity, struct GNUNET_TIME_Absolute expiration, uint64_t uid) { unsigned long long *need = cls; if (NULL == key) { GNUNET_free (need); return GNUNET_SYSERR; } if (size + GNUNET_DATASTORE_ENTRY_OVERHEAD > *need) *need = 0; else *need -= size + GNUNET_DATASTORE_ENTRY_OVERHEAD; plugin->api->next_request (next_cls, (0 == *need) ? GNUNET_YES : GNUNET_NO); #if DEBUG_DATASTORE GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Deleting %llu bytes of low-priority content (still trying to recover %llu bytes)\n", size + GNUNET_DATASTORE_ENTRY_OVERHEAD, *need); #endif GNUNET_CONTAINER_bloomfilter_remove (filter, key); return GNUNET_NO; } /** * Manage available disk space by running tasks * that will discard content if necessary. This * function will be run whenever a request for * "need" bytes of storage could only be satisfied * by eating into the "cache" (and we want our cache * space back). * * @param need number of bytes of content that were * placed into the "cache" (and hence the * number of bytes that should be removed). */ static void manage_space (unsigned long long need) { unsigned long long *n; #if DEBUG_DATASTORE GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Asked to recover %llu bytes of cache space\n", need); #endif n = GNUNET_malloc (sizeof(unsigned long long)); *n = need; plugin->api->iter_low_priority (plugin->api->cls, 0, &manage, n); } /** * Function called to notify a client about the socket * begin ready to queue more data. "buf" will be * NULL and "size" zero if the socket was closed for * writing in the meantime. * * @param cls closure * @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_callback (void *cls, size_t size, void *buf) { struct TransmitCallbackContext *tcc = cls; size_t msize; msize = ntohs(tcc->msg->size); if (size == 0) { #if DEBUG_DATASTORE GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "Transmission failed.\n"); #endif if (tcc->tc != NULL) tcc->tc (tcc->tc_cls, GNUNET_SYSERR); if (GNUNET_YES == tcc->end) { GNUNET_SERVER_receive_done (tcc->client, GNUNET_SYSERR); } GNUNET_free (tcc->msg); GNUNET_free (tcc); return 0; } GNUNET_assert (size >= msize); memcpy (buf, tcc->msg, msize); if (tcc->tc != NULL) tcc->tc (tcc->tc_cls, GNUNET_OK); if (GNUNET_YES == tcc->end) { GNUNET_SERVER_receive_done (tcc->client, GNUNET_OK); } else { #if DEBUG_DATASTORE GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Response transmitted, more pending!\n"); #endif } GNUNET_free (tcc->msg); GNUNET_free (tcc); return msize; } /** * Transmit the given message to the client. * * @param client target of the message * @param msg message to transmit, will be freed! * @param end is this the last response (and we should * signal the server completion accodingly after * transmitting this message)? */ static void transmit (struct GNUNET_SERVER_Client *client, struct GNUNET_MessageHeader *msg, TransmitContinuation tc, void *tc_cls, int end) { struct TransmitCallbackContext *tcc; tcc = GNUNET_malloc (sizeof(struct TransmitCallbackContext)); tcc->msg = msg; tcc->client = client; tcc->tc = tc; tcc->tc_cls = tc_cls; tcc->end = end; if (NULL == GNUNET_SERVER_notify_transmit_ready (client, ntohs(msg->size), GNUNET_TIME_UNIT_FOREVER_REL, &transmit_callback, tcc)) { GNUNET_break (0); if (GNUNET_YES == end) { #if DEBUG_DATASTORE GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "Disconnecting client.\n"); #endif GNUNET_SERVER_receive_done (client, GNUNET_SYSERR); } if (NULL != tc) tc (tc_cls, GNUNET_SYSERR); GNUNET_free (msg); GNUNET_free (tcc); } } /** * Transmit a status code to the client. * * @param client receiver of the response * @param code status code * @param msg optional error message (can be NULL) */ static void transmit_status (struct GNUNET_SERVER_Client *client, int code, const char *msg) { struct StatusMessage *sm; size_t slen; #if DEBUG_DATASTORE GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmitting `%s' message with value %d and message `%s'\n", "STATUS", code, msg != NULL ? msg : "(none)"); #endif slen = (msg == NULL) ? 0 : strlen(msg) + 1; sm = GNUNET_malloc (sizeof(struct StatusMessage) + slen); sm->header.size = htons(sizeof(struct StatusMessage) + slen); sm->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_STATUS); sm->status = htonl(code); if (slen > 0) memcpy (&sm[1], msg, slen); transmit (client, &sm->header, NULL, NULL, GNUNET_YES); } /** * Function called once the transmit operation has * either failed or succeeded. * * @param cls closure * @param status GNUNET_OK on success, GNUNET_SYSERR on error */ static void get_next(void *next_cls, int status) { if (status != GNUNET_OK) { GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("Failed to transmit an item to the client; aborting iteration.\n")); plugin->api->next_request (next_cls, GNUNET_YES); return; } plugin->api->next_request (next_cls, GNUNET_NO); } /** * Function that will transmit the given datastore entry * to the client. * * @param cls closure, pointer to the client (of type GNUNET_SERVER_Client). * @param next_cls closure to use to ask for the next item * @param key key for the content * @param size number of bytes in data * @param data content stored * @param type type of the content * @param priority priority of the content * @param anonymity anonymity-level for the content * @param expiration expiration time for the content * @param uid unique identifier for the datum; * maybe 0 if no unique identifier is available * * @return GNUNET_SYSERR to abort the iteration, GNUNET_OK to continue, * GNUNET_NO to delete the item and continue (if supported) */ static int transmit_item (void *cls, void *next_cls, const GNUNET_HashCode * key, uint32_t size, const void *data, uint32_t type, uint32_t priority, uint32_t anonymity, struct GNUNET_TIME_Absolute expiration, uint64_t uid) { struct GNUNET_SERVER_Client *client = cls; struct GNUNET_MessageHeader *end; struct DataMessage *dm; if (key == NULL) { /* transmit 'DATA_END' */ #if DEBUG_DATASTORE GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmitting `%s' message\n", "DATA_END"); #endif end = GNUNET_malloc (sizeof(struct GNUNET_MessageHeader)); end->size = htons(sizeof(struct GNUNET_MessageHeader)); end->type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_DATA_END); transmit (client, end, NULL, NULL, GNUNET_YES); GNUNET_SERVER_client_drop (client); return GNUNET_OK; } dm = GNUNET_malloc (sizeof(struct DataMessage) + size); dm->header.size = htons(sizeof(struct DataMessage) + size); dm->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_DATA); dm->rid = htonl(0); dm->size = htonl(size); dm->type = htonl(type); dm->priority = htonl(priority); dm->anonymity = htonl(anonymity); dm->expiration = GNUNET_TIME_absolute_hton(expiration); dm->uid = GNUNET_htonll(uid); dm->key = *key; memcpy (&dm[1], data, size); #if DEBUG_DATASTORE GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmitting `%s' message\n", "DATA"); #endif transmit (client, &dm->header, &get_next, next_cls, GNUNET_NO); return GNUNET_OK; } /** * Handle RESERVE-message. * * @param cls closure * @param client identification of the client * @param message the actual message */ static void handle_reserve (void *cls, struct GNUNET_SERVER_Client *client, const struct GNUNET_MessageHeader *message) { const struct ReserveMessage *msg = (const struct ReserveMessage*) message; struct ReservationList *e; unsigned long long used; unsigned long long req; uint64_t amount; uint32_t entries; #if DEBUG_DATASTORE GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Processing `%s' request\n", "RESERVE"); #endif amount = GNUNET_ntohll(msg->amount); entries = ntohl(msg->entries); used = plugin->api->get_size (plugin->api->cls) + reserved; req = amount + ((unsigned long long) GNUNET_DATASTORE_ENTRY_OVERHEAD) * entries; if (used + req > quota) { if (quota < used) used = quota; /* cheat a bit for error message (to avoid negative numbers) */ GNUNET_log (GNUNET_ERROR_TYPE_WARNING, _("Insufficient space (%llu bytes are available) to satisfy `%s' request for %llu bytes\n"), quota - used, "RESERVE", req); if (cache_size < req) { /* TODO: document this in the FAQ; essentially, if this message happens, the insertion request could be blocked by less-important content from migration because it is larger than 1/8th of the overall available space, and we only reserve 1/8th for "fresh" insertions */ GNUNET_log (GNUNET_ERROR_TYPE_WARNING, _("The requested amount (%llu bytes) is larger than the cache size (%llu bytes)\n"), req, cache_size); transmit_status (client, 0, gettext_noop ("Insufficient space to satisfy request and " "requested amount is larger than cache size")); } else { transmit_status (client, 0, gettext_noop ("Insufficient space to satisfy request")); } return; } reserved += req; e = GNUNET_malloc (sizeof(struct ReservationList)); e->next = reservations; reservations = e; e->client = client; e->amount = amount; e->entries = entries; e->rid = ++reservation_gen; if (reservation_gen < 0) reservation_gen = 0; /* wrap around */ transmit_status (client, e->rid, NULL); } /** * Handle RELEASE_RESERVE-message. * * @param cls closure * @param client identification of the client * @param message the actual message */ static void handle_release_reserve (void *cls, struct GNUNET_SERVER_Client *client, const struct GNUNET_MessageHeader *message) { const struct ReleaseReserveMessage *msg = (const struct ReleaseReserveMessage*) message; struct ReservationList *pos; struct ReservationList *prev; struct ReservationList *next; int rid = ntohl(msg->rid); unsigned long long rem; #if DEBUG_DATASTORE GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Processing `%s' request\n", "RELEASE_RESERVE"); #endif next = reservations; prev = NULL; while (NULL != (pos = next)) { next = pos->next; if (rid == pos->rid) { if (prev == NULL) reservations = next; else prev->next = next; rem = pos->amount + ((unsigned long long) GNUNET_DATASTORE_ENTRY_OVERHEAD) * pos->entries; GNUNET_assert (reserved >= rem); reserved -= rem; #if DEBUG_DATASTORE GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Returning %llu remaining reserved bytes to storage pool\n", rem); #endif GNUNET_free (pos); transmit_status (client, GNUNET_OK, NULL); return; } prev = pos; } GNUNET_break (0); transmit_status (client, GNUNET_SYSERR, gettext_noop ("Could not find matching reservation")); } /** * Check that the given message is a valid data message. * * @return NULL if the message is not well-formed, otherwise the message */ static const struct DataMessage * check_data (const struct GNUNET_MessageHeader *message) { uint16_t size; uint32_t dsize; const struct DataMessage *dm; size = ntohs(message->size); if (size < sizeof(struct DataMessage)) { GNUNET_break (0); return NULL; } dm = (const struct DataMessage *) message; dsize = ntohl(dm->size); if (size != dsize + sizeof(struct DataMessage)) { GNUNET_break (0); return NULL; } return dm; } /** * Handle PUT-message. * * @param cls closure * @param client identification of the client * @param message the actual message */ static void handle_put (void *cls, struct GNUNET_SERVER_Client *client, const struct GNUNET_MessageHeader *message) { const struct DataMessage *dm = check_data (message); char *msg; int ret; int rid; struct ReservationList *pos; uint32_t size; #if DEBUG_DATASTORE GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Processing `%s' request\n", "PUT"); #endif if (ntohl(dm->type) == 0) { GNUNET_break (0); dm = NULL; } if (dm == NULL) { GNUNET_break (0); GNUNET_SERVER_receive_done (client, GNUNET_SYSERR); return; } rid = ntohl(dm->rid); size = ntohl(dm->size); if (rid > 0) { pos = reservations; while ( (NULL != pos) && (rid != pos->rid) ) pos = pos->next; GNUNET_break (pos != NULL); if (NULL != pos) { GNUNET_break (pos->entries > 0); GNUNET_break (pos->amount > size); pos->entries--; pos->amount -= size; reserved -= (size + GNUNET_DATASTORE_ENTRY_OVERHEAD); } } msg = NULL; ret = plugin->api->put (plugin->api->cls, &dm->key, size, &dm[1], ntohl(dm->type), ntohl(dm->priority), ntohl(dm->anonymity), GNUNET_TIME_absolute_ntoh(dm->expiration), &msg); if (GNUNET_OK == ret) GNUNET_CONTAINER_bloomfilter_add (filter, &dm->key); transmit_status (client, (GNUNET_SYSERR == ret) ? GNUNET_SYSERR : GNUNET_OK, msg); GNUNET_free_non_null (msg); if (quota - reserved - cache_size < plugin->api->get_size (plugin->api->cls)) manage_space (size + GNUNET_DATASTORE_ENTRY_OVERHEAD); } /** * Handle GET-message. * * @param cls closure * @param client identification of the client * @param message the actual message */ static void handle_get (void *cls, struct GNUNET_SERVER_Client *client, const struct GNUNET_MessageHeader *message) { const struct GetMessage *msg; uint16_t size; #if DEBUG_DATASTORE GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Processing `%s' request\n", "GET"); #endif size = ntohs(message->size); if ( (size != sizeof(struct GetMessage)) && (size != sizeof(struct GetMessage) - sizeof(GNUNET_HashCode)) ) { GNUNET_break (0); GNUNET_SERVER_receive_done (client, GNUNET_SYSERR); return; } msg = (const struct GetMessage*) message; if ( (size == sizeof(struct GetMessage)) && (GNUNET_YES != GNUNET_CONTAINER_bloomfilter_test (filter, &msg->key)) ) { /* don't bother database... */ #if DEBUG_DATASTORE GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Empty result set for `%s' request.\n", "GET"); #endif transmit_item (client, NULL, NULL, 0, NULL, 0, 0, 0, GNUNET_TIME_UNIT_ZERO_ABS, 0); return; } GNUNET_SERVER_client_keep (client); plugin->api->get (plugin->api->cls, ((size == sizeof(struct GetMessage)) ? &msg->key : NULL), NULL, ntohl(msg->type), &transmit_item, client); } /** * Handle UPDATE-message. * * @param cls closure * @param client identification of the client * @param message the actual message */ static void handle_update (void *cls, struct GNUNET_SERVER_Client *client, const struct GNUNET_MessageHeader *message) { const struct UpdateMessage *msg; int ret; char *emsg; #if DEBUG_DATASTORE GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Processing `%s' request\n", "UPDATE"); #endif msg = (const struct UpdateMessage*) message; emsg = NULL; ret = plugin->api->update (plugin->api->cls, GNUNET_ntohll(msg->uid), (int32_t) ntohl(msg->priority), GNUNET_TIME_absolute_ntoh(msg->expiration), &emsg); transmit_status (client, ret, emsg); GNUNET_free_non_null (emsg); } /** * Handle GET_RANDOM-message. * * @param cls closure * @param client identification of the client * @param message the actual message */ static void handle_get_random (void *cls, struct GNUNET_SERVER_Client *client, const struct GNUNET_MessageHeader *message) { #if DEBUG_DATASTORE GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Processing `%s' request\n", "GET_RANDOM"); #endif GNUNET_SERVER_client_keep (client); plugin->api->iter_migration_order (plugin->api->cls, 0, &transmit_item, client); } /** * Context for the 'remove_callback'. */ struct RemoveContext { /** * Client for whom we're doing the remvoing. */ struct GNUNET_SERVER_Client *client; /** * GNUNET_YES if we managed to remove something. */ int found; }; /** * Callback function that will cause the item that is passed * in to be deleted (by returning GNUNET_NO). */ static int remove_callback (void *cls, void *next_cls, const GNUNET_HashCode * key, uint32_t size, const void *data, uint32_t type, uint32_t priority, uint32_t anonymity, struct GNUNET_TIME_Absolute expiration, uint64_t uid) { struct RemoveContext *rc = cls; if (key == NULL) { #if DEBUG_DATASTORE GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "No further matches for `%s' request.\n", "REMOVE"); #endif if (GNUNET_YES == rc->found) transmit_status (rc->client, GNUNET_OK, NULL); else transmit_status (rc->client, GNUNET_NO, _("Content not found")); GNUNET_SERVER_client_drop (rc->client); GNUNET_free (rc); return GNUNET_OK; /* last item */ } rc->found = GNUNET_YES; #if DEBUG_DATASTORE GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Item %llu matches `%s' request.\n", (unsigned long long) uid, "REMOVE"); #endif GNUNET_CONTAINER_bloomfilter_remove (filter, key); plugin->api->next_request (next_cls, GNUNET_YES); return GNUNET_NO; } /** * Handle REMOVE-message. * * @param cls closure * @param client identification of the client * @param message the actual message */ static void handle_remove (void *cls, struct GNUNET_SERVER_Client *client, const struct GNUNET_MessageHeader *message) { const struct DataMessage *dm = check_data (message); GNUNET_HashCode vhash; struct RemoveContext *rc; #if DEBUG_DATASTORE GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Processing `%s' request\n", "REMOVE"); #endif if (dm == NULL) { GNUNET_break (0); GNUNET_SERVER_receive_done (client, GNUNET_SYSERR); return; } rc = GNUNET_malloc (sizeof(struct RemoveContext)); GNUNET_SERVER_client_keep (client); rc->client = client; GNUNET_CRYPTO_hash (&dm[1], ntohl(dm->size), &vhash); GNUNET_SERVER_client_keep (client); plugin->api->get (plugin->api->cls, &dm->key, &vhash, ntohl(dm->type), &remove_callback, rc); } /** * Handle DROP-message. * * @param cls closure * @param client identification of the client * @param message the actual message */ static void handle_drop (void *cls, struct GNUNET_SERVER_Client *client, const struct GNUNET_MessageHeader *message) { #if DEBUG_DATASTORE GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Processing `%s' request\n", "DROP"); #endif plugin->api->drop (plugin->api->cls); GNUNET_SERVER_receive_done (client, GNUNET_OK); } /** * List of handlers for the messages understood by this * service. */ static struct GNUNET_SERVER_MessageHandler handlers[] = { {&handle_reserve, NULL, GNUNET_MESSAGE_TYPE_DATASTORE_RESERVE, sizeof(struct ReserveMessage) }, {&handle_release_reserve, NULL, GNUNET_MESSAGE_TYPE_DATASTORE_RELEASE_RESERVE, sizeof(struct ReleaseReserveMessage) }, {&handle_put, NULL, GNUNET_MESSAGE_TYPE_DATASTORE_PUT, 0 }, {&handle_update, NULL, GNUNET_MESSAGE_TYPE_DATASTORE_UPDATE, sizeof (struct UpdateMessage) }, {&handle_get, NULL, GNUNET_MESSAGE_TYPE_DATASTORE_GET, 0 }, {&handle_get_random, NULL, GNUNET_MESSAGE_TYPE_DATASTORE_GET_RANDOM, sizeof(struct GNUNET_MessageHeader) }, {&handle_remove, NULL, GNUNET_MESSAGE_TYPE_DATASTORE_REMOVE, 0 }, {&handle_drop, NULL, GNUNET_MESSAGE_TYPE_DATASTORE_DROP, sizeof(struct GNUNET_MessageHeader) }, {NULL, NULL, 0, 0} }; /** * Load the datastore plugin. */ static struct DatastorePlugin * load_plugin () { struct DatastorePlugin *ret; char *libname; char *name; if (GNUNET_OK != GNUNET_CONFIGURATION_get_value_string (cfg, "DATASTORE", "DATABASE", &name)) { GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("No `%s' specified for `%s' in configuration!\n"), "DATABASE", "DATASTORE"); return NULL; } ret = GNUNET_malloc (sizeof(struct DatastorePlugin)); ret->env.cfg = cfg; ret->env.sched = sched; GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("Loading `%s' datastore plugin\n"), name); GNUNET_asprintf (&libname, "libgnunet_plugin_datastore_%s", name); ret->short_name = name; ret->lib_name = libname; ret->api = GNUNET_PLUGIN_load (libname, &ret->env); if (ret->api == NULL) { GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("Failed to load datastore plugin for `%s'\n"), name); GNUNET_free (ret->short_name); GNUNET_free (libname); GNUNET_free (ret); return NULL; } return ret; } /** * Function called when the service shuts * down. Unloads our datastore plugin. * * @param plug plugin to unload */ static void unload_plugin (struct DatastorePlugin *plug) { #if DEBUG_DATASTORE GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Datastore service is unloading plugin...\n"); #endif GNUNET_break (NULL == GNUNET_PLUGIN_unload (plug->lib_name, plug->api)); GNUNET_free (plug->lib_name); GNUNET_free (plug->short_name); GNUNET_free (plug); } /** * Last task run during shutdown. Disconnects us from * the transport and core. */ static void cleaning_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { unload_plugin (plugin); plugin = NULL; } /** * Function that removes all active reservations made * by the given client and releases the space for other * requests. * * @param cls closure * @param client identification of the client */ static void cleanup_reservations (void *cls, struct GNUNET_SERVER_Client * client) { struct ReservationList *pos; struct ReservationList *prev; struct ReservationList *next; prev = NULL; pos = reservations; while (NULL != pos) { next = pos->next; if (pos->client == client) { if (prev == NULL) reservations = next; else prev->next = next; reserved -= pos->amount + pos->entries * GNUNET_DATASTORE_ENTRY_OVERHEAD; GNUNET_free (pos); } else { prev = pos; } pos = next; } } /** * Process datastore requests. * * @param cls closure * @param s scheduler to use * @param server the initialized server * @param c configuration to use */ static void run (void *cls, struct GNUNET_SCHEDULER_Handle *s, struct GNUNET_SERVER_Handle *server, const struct GNUNET_CONFIGURATION_Handle *c) { char *fn; unsigned int bf_size; sched = s; cfg = c; if (GNUNET_OK != GNUNET_CONFIGURATION_get_value_number (cfg, "DATASTORE", "QUOTA", "a)) { GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("No `%s' specified for `%s' in configuration!\n"), "QUOTA", "DATASTORE"); return; } cache_size = quota / 8; /* Or should we make this an option? */ bf_size = quota / 32; /* 8 bit per entry, 1 bit per 32 kb in DB */ fn = NULL; if ( (GNUNET_OK != GNUNET_CONFIGURATION_get_value_filename (cfg, "DATASTORE", "BLOOMFILTER", &fn)) || (GNUNET_OK != GNUNET_DISK_directory_create_for_file (fn)) ) { GNUNET_log (GNUNET_ERROR_TYPE_WARNING, _("Could not use specified filename `%s' for bloomfilter.\n"), fn != NULL ? fn : ""); GNUNET_free_non_null (fn); fn = NULL; } filter = GNUNET_CONTAINER_bloomfilter_load (fn, bf_size, 5); /* approx. 3% false positives at max use */ GNUNET_free_non_null (fn); if (filter == NULL) { GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("Failed to initialize bloomfilter.\n")); return; } plugin = load_plugin (); if (NULL == plugin) { GNUNET_CONTAINER_bloomfilter_free (filter); return; } GNUNET_SERVER_disconnect_notify (server, &cleanup_reservations, NULL); GNUNET_SERVER_add_handlers (server, handlers); expired_kill_task = GNUNET_SCHEDULER_add_delayed (sched, GNUNET_NO, GNUNET_SCHEDULER_PRIORITY_IDLE, GNUNET_SCHEDULER_NO_TASK, GNUNET_TIME_UNIT_ZERO, &delete_expired, NULL); GNUNET_SCHEDULER_add_delayed (sched, GNUNET_YES, GNUNET_SCHEDULER_PRIORITY_IDLE, GNUNET_SCHEDULER_NO_TASK, GNUNET_TIME_UNIT_FOREVER_REL, &cleaning_task, NULL); } /** * The main function for the datastore service. * * @param argc number of arguments from the command line * @param argv command line arguments * @return 0 ok, 1 on error */ int main (int argc, char *const *argv) { int ret; ret = (GNUNET_OK == GNUNET_SERVICE_run (argc, argv, "datastore", &run, NULL, NULL, NULL)) ? 0 : 1; return ret; } /* end of gnunet-service-datastore.c */