--- /dev/null
+/*
+ This file is part of GNUnet
+ (C) 2006, 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 3, 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 datacache/plugin_datacache_postgres.c
+ * @brief postgres for an implementation of a database backend for the datacache
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include "gnunet_util_lib.h"
+#include "plugin_datacache.h"
+#include <postgresql/libpq-fe.h>
+
+#define DEBUG_POSTGRES GNUNET_NO
+
+
+
+/**
+ * Context for all functions in this plugin.
+ */
+struct Plugin
+{
+ /**
+ * Our execution environment.
+ */
+ struct GNUNET_DATACACHE_PluginEnvironment *env;
+
+ /**
+ * Native Postgres database handle.
+ */
+ PGconn *dbh;
+
+};
+
+
+/**
+ * Check if the result obtained from Postgres has
+ * the desired status code. If not, log an error, clear the
+ * result and return GNUNET_SYSERR.
+ *
+ * @return GNUNET_OK if the result is acceptable
+ */
+static int
+check_result (struct Plugin *plugin,
+ PGresult * ret,
+ int expected_status,
+ const char *command, const char *args, int line)
+{
+ if (ret == NULL)
+ {
+ GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
+ "datastore-postgres",
+ "Postgres failed to allocate result for `%s:%s' at %d\n",
+ command, args, line);
+ return GNUNET_SYSERR;
+ }
+ if (PQresultStatus (ret) != expected_status)
+ {
+ GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
+ "datastore-postgres",
+ _("`%s:%s' failed at %s:%d with error: %s"),
+ command, args, __FILE__, line, PQerrorMessage (plugin->dbh));
+ PQclear (ret);
+ return GNUNET_SYSERR;
+ }
+ return GNUNET_OK;
+}
+
+
+/**
+ * Run simple SQL statement (without results).
+ */
+static int
+pq_exec (struct Plugin *plugin,
+ const char *sql, int line)
+{
+ PGresult *ret;
+ ret = PQexec (plugin->dbh, sql);
+ if (GNUNET_OK != check_result (plugin,
+ ret,
+ PGRES_COMMAND_OK, "PQexec", sql, line))
+ return GNUNET_SYSERR;
+ PQclear (ret);
+ return GNUNET_OK;
+}
+
+
+/**
+ * Prepare SQL statement.
+ */
+static int
+pq_prepare (struct Plugin *plugin,
+ const char *name, const char *sql, int nparms, int line)
+{
+ PGresult *ret;
+ ret = PQprepare (plugin->dbh, name, sql, nparms, NULL);
+ if (GNUNET_OK !=
+ check_result (plugin,
+ ret, PGRES_COMMAND_OK, "PQprepare", sql, line))
+ return GNUNET_SYSERR;
+ PQclear (ret);
+ return GNUNET_OK;
+}
+
+
+/**
+ * @brief Get a database handle
+ * @return GNUNET_OK on success, GNUNET_SYSERR on error
+ */
+static int
+init_connection (struct Plugin *plugin)
+{
+ char *conninfo;
+ PGresult *ret;
+
+ /* Open database and precompile statements */
+ conninfo = NULL;
+ GNUNET_CONFIGURATION_get_value_string (plugin->env->cfg,
+ "datacache-postgres",
+ "CONFIG",
+ &conninfo);
+ plugin->dbh = PQconnectdb (conninfo == NULL ? "" : conninfo);
+ GNUNET_free_non_null (conninfo);
+ if (NULL == plugin->dbh)
+ {
+ /* FIXME: warn about out-of-memory? */
+ return GNUNET_SYSERR;
+ }
+ if (PQstatus (plugin->dbh) != CONNECTION_OK)
+ {
+ GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR,
+ "datacache-postgres",
+ _("Unable to initialize Postgres: %s"),
+ PQerrorMessage (plugin->dbh));
+ PQfinish (plugin->dbh);
+ plugin->dbh = NULL;
+ return GNUNET_SYSERR;
+ }
+ ret = PQexec (plugin->dbh,
+ "CREATE TEMPORARY `TABLE gn090dc ("
+ " type INTEGER NOT NULL DEFAULT 0,"
+ " discard_time BIGINT NOT NULL DEFAULT 0,"
+ " key BYTEA NOT NULL DEFAULT '',"
+ " value BYTEA NOT NULL DEFAULT '')" "WITH OIDS");
+ if ( (ret == NULL) ||
+ ( (PQresultStatus (ret) != PGRES_COMMAND_OK) &&
+ (0 != strcmp ("42P07", /* duplicate table */
+ PQresultErrorField
+ (ret,
+ PG_DIAG_SQLSTATE)))))
+ {
+ check_result (plugin,
+ ret, PGRES_COMMAND_OK, "CREATE TABLE", "gn090dc", __LINE__);
+ PQfinish (plugin->dbh);
+ plugin->dbh = NULL;
+ return GNUNET_SYSERR;
+ }
+ if (PQresultStatus (ret) == PGRES_COMMAND_OK)
+ {
+ if ((GNUNET_OK !=
+ pq_exec (plugin, "CREATE INDEX idx_key ON gn090dc (key)", __LINE__)) ||
+ (GNUNET_OK !=
+ pq_exec (plugin, "CREATE INDEX idx_dt ON gn090 (discard_time)",
+ __LINE__)) )
+ {
+ PQclear (ret);
+ PQfinish (plugin->dbh);
+ plugin->dbh = NULL;
+ return GNUNET_SYSERR;
+ }
+ }
+ PQclear (ret);
+#if 1
+ ret = PQexec (plugin->dbh,
+ "ALTER TABLE gn090dc ALTER value SET STORAGE EXTERNAL");
+ if (GNUNET_OK !=
+ check_result (plugin,
+ ret, PGRES_COMMAND_OK,
+ "ALTER TABLE", "gn090dc", __LINE__))
+ {
+ PQfinish (plugin->dbh);
+ plugin->dbh = NULL;
+ return GNUNET_SYSERR;
+ }
+ PQclear (ret);
+ ret = PQexec (plugin->dbh,
+ "ALTER TABLE gn090dc ALTER key SET STORAGE PLAIN");
+ if (GNUNET_OK !=
+ check_result (plugin,
+ ret, PGRES_COMMAND_OK,
+ "ALTER TABLE", "gn090dc", __LINE__))
+ {
+ PQfinish (plugin->dbh);
+ plugin->dbh = NULL;
+ return GNUNET_SYSERR;
+ }
+ PQclear (ret);
+#endif
+ if ((GNUNET_OK !=
+ pq_prepare (plugin,
+ "getkt",
+ "SELECT discard_time,type,value FROM gn090dc "
+ "WHERE hash=$1 type=$2 ",
+ 2,
+ __LINE__)) ||
+ (GNUNET_OK !=
+ pq_prepare (plugin,
+ "getk",
+ "SELECT discard_time,type,value FROM gn090dc "
+ "WHERE hash=$1",
+ 1,
+ __LINE__)) ||
+ (GNUNET_OK !=
+ pq_prepare (plugin,
+ "getm",
+ "SELECT length(value),oid FROM gn090dc"
+ "ORDER BY discard_time ASC LIMIT 1",
+ 0,
+ __LINE__)) ||
+ (GNUNET_OK !=
+ pq_prepare (plugin,
+ "delrow",
+ "DELETE FROM gn090dc WHERE oid=$1",
+ 1,
+ __LINE__)) ||
+ (GNUNET_OK !=
+ pq_prepare (plugin,
+ "put",
+ "INSERT INTO gn090dc (type, discard_time, key, value) "
+ "VALUES ($1, $2, $3, $4)",
+ 4,
+ __LINE__)) )
+ {
+ PQfinish (plugin->dbh);
+ plugin->dbh = NULL;
+ return GNUNET_SYSERR;
+ }
+ return GNUNET_OK;
+}
+
+
+/**
+ * Delete the row identified by the given rowid (qid
+ * in postgres).
+ *
+ * @return GNUNET_OK on success
+ */
+static int
+delete_by_rowid (struct Plugin *plugin,
+ unsigned int rowid)
+{
+ const char *paramValues[] = { (const char *) &rowid };
+ int paramLengths[] = { sizeof (rowid) };
+ const int paramFormats[] = { 1 };
+ PGresult *ret;
+
+ ret = PQexecPrepared (plugin->dbh,
+ "delrow",
+ 1, paramValues, paramLengths, paramFormats, 1);
+ if (GNUNET_OK !=
+ check_result (plugin,
+ ret, PGRES_COMMAND_OK, "PQexecPrepared", "delrow",
+ __LINE__))
+ {
+ return GNUNET_SYSERR;
+ }
+ PQclear (ret);
+ return GNUNET_OK;
+}
+
+
+/**
+ * Store an item in the datastore.
+ *
+ * @param cls closure (our "struct Plugin")
+ * @param key key to store data under
+ * @param size number of bytes in data
+ * @param data data to store
+ * @param type type of the value
+ * @param discard_time when to discard the value in any case
+ * @return 0 on error, number of bytes used otherwise
+ */
+static uint32_t
+postgres_plugin_put (void *cls,
+ const GNUNET_HashCode * key,
+ uint32_t size,
+ const char *data,
+ enum GNUNET_BLOCK_Type type,
+ struct GNUNET_TIME_Absolute discard_time)
+{
+ struct Plugin *plugin = cls;
+ PGresult *ret;
+ uint32_t btype = htonl (type);
+ uint64_t bexpi = GNUNET_TIME_absolute_hton (discard_time).value__;
+ const char *paramValues[] = {
+ (const char *) &btype,
+ (const char *) &bexpi,
+ (const char *) key,
+ (const char *) data
+ };
+ int paramLengths[] = {
+ sizeof (btype),
+ sizeof (bexpi),
+ sizeof (GNUNET_HashCode),
+ size
+ };
+ const int paramFormats[] = { 1, 1, 1, 1 };
+
+ ret = PQexecPrepared (plugin->dbh,
+ "put", 4, paramValues, paramLengths, paramFormats, 1);
+ if (GNUNET_OK != check_result (plugin, ret,
+ PGRES_COMMAND_OK,
+ "PQexecPrepared", "put", __LINE__))
+ return GNUNET_SYSERR;
+ PQclear (ret);
+ return size;
+}
+
+
+/**
+ * Iterate over the results for a particular key
+ * in the datastore.
+ *
+ * @param cls closure (our "struct Plugin")
+ * @param key
+ * @param type entries of which type are relevant?
+ * @param iter maybe NULL (to just count)
+ * @param iter_cls closure for iter
+ * @return the number of results found
+ */
+static unsigned int
+postgres_plugin_get (void *cls,
+ const GNUNET_HashCode * key,
+ enum GNUNET_BLOCK_Type type,
+ GNUNET_DATACACHE_Iterator iter,
+ void *iter_cls)
+{
+ struct Plugin *plugin = cls;
+ uint32_t btype = htonl (type);
+ const char *paramValues[] = {
+ (const char *) key,
+ (const char *) &btype,
+ };
+ int paramLengths[] = {
+ sizeof (GNUNET_HashCode),
+ sizeof (btype),
+ };
+ const int paramFormats[] = { 1, 1 };
+ struct GNUNET_TIME_Absolute expiration_time;
+ uint32_t size;
+ unsigned int cnt;
+ unsigned int i;
+ PGresult *res;
+
+ cnt = 0;
+ res = PQexecPrepared (plugin->dbh,
+ (type == 0) ? "getk" : "getkt",
+ (type == 0) ? 1 : 2,
+ paramValues,
+ paramLengths,
+ paramFormats,
+ 1);
+ if (GNUNET_OK != check_result (plugin,
+ res,
+ PGRES_TUPLES_OK,
+ "PQexecPrepared",
+ (type == 0) ? "getk" : "getkt",
+ __LINE__))
+ {
+#if DEBUG_POSTGRES
+ GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
+ "datacache-postgres",
+ "Ending iteration (postgres error)\n");
+#endif
+ return 0;
+ }
+
+ if (0 == (cnt = PQntuples (res)))
+ {
+ /* no result */
+#if DEBUG_POSTGRES
+ GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
+ "datacache-postgres",
+ "Ending iteration (no more results)\n");
+#endif
+ PQclear (res);
+ return 0;
+ }
+ if ( (3 != PQnfields (res)) ||
+ (sizeof (uint64_t) != PQfsize (res, 0)) ||
+ (sizeof (uint32_t) != PQfsize (res, 1)))
+ {
+ GNUNET_break (0);
+ PQclear (res);
+ return 0;
+ }
+ for (i=0;i<cnt;i++)
+ {
+ expiration_time.value = GNUNET_ntohll (*(uint64_t *) PQgetvalue (res, i, 0));
+ type = ntohl (*(uint32_t *) PQgetvalue (res, i, 1));
+ size = PQgetlength (res, i, 2);
+#if DEBUG_POSTGRES
+ GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
+ "datacache-postgres",
+ "Found result of size %u bytes and type %u in database\n",
+ (unsigned int) size,
+ (unsigned int) type);
+#endif
+ if (GNUNET_SYSERR ==
+ iter (iter_cls,
+ expiration_time,
+ key,
+ size,
+ PQgetvalue (res, i, 2),
+ (enum GNUNET_BLOCK_Type) type))
+ {
+#if DEBUG_POSTGRES
+ GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
+ "datacache-postgres",
+ "Ending iteration (client error)\n");
+#endif
+ PQclear (res);
+ return cnt;
+ }
+ }
+ PQclear (res);
+ return cnt;
+}
+
+
+/**
+ * Delete the entry with the lowest expiration value
+ * from the datacache right now.
+ *
+ * @param cls closure (our "struct Plugin")
+ * @return GNUNET_OK on success, GNUNET_SYSERR on error
+ */
+static int
+postgres_plugin_del (void *cls)
+{
+
+ GNUNET_break (0);
+ return GNUNET_SYSERR;
+}
+
+
+/**
+ * Entry point for the plugin.
+ *
+ * @param cls closure (the "struct GNUNET_DATACACHE_PluginEnvironmnet")
+ * @return the plugin's closure (our "struct Plugin")
+ */
+void *
+libgnunet_plugin_datacache_postgres_init (void *cls)
+{
+ struct GNUNET_DATACACHE_PluginEnvironment *env = cls;
+ struct GNUNET_DATACACHE_PluginFunctions *api;
+ struct Plugin *plugin;
+
+ plugin = GNUNET_malloc (sizeof (struct Plugin));
+ plugin->env = env;
+
+ if (GNUNET_OK !=
+ init_connection (plugin))
+ {
+ GNUNET_free (plugin);
+ return NULL;
+ }
+
+ api = GNUNET_malloc (sizeof (struct GNUNET_DATACACHE_PluginFunctions));
+ api->cls = plugin;
+ api->get = &postgres_plugin_get;
+ api->put = &postgres_plugin_put;
+ api->del = &postgres_plugin_del;
+ GNUNET_log_from (GNUNET_ERROR_TYPE_INFO,
+ "datacache-postgres",
+ _("Postgres datacache running\n"));
+ return api;
+}
+
+
+/**
+ * Exit point from the plugin.
+ *
+ * @param cls closure (our "struct Plugin")
+ * @return NULL
+ */
+void *
+libgnunet_plugin_datacache_postgres_done (void *cls)
+{
+ struct GNUNET_DATACACHE_PluginFunctions *api = cls;
+ struct Plugin *plugin = api->cls;
+
+ GNUNET_free (plugin);
+ GNUNET_free (api);
+ return NULL;
+}
+
+
+
+/* end of plugin_datacache_postgres.c */
+
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