/*
This file is part of GNUnet
- (C) 2009, 2010 Christian Grothoff (and other contributing authors)
+ (C) 2011 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
* @brief API to retrieve the current network size estimate,
* also to register for notifications whenever a new
* network size estimate is calculated.
- *
* @author Nathan Evans
+ * @defgroup nse network size estimation service
+ * @{
*/
#ifdef __cplusplus
#endif
#endif
-#include "gnunet_common.h"
-#include "gnunet_configuration_lib.h"
-#include "gnunet_scheduler_lib.h"
+#include "gnunet_util_lib.h"
/**
* Version of the network size estimation API.
*/
#define GNUNET_NSE_VERSION 0x00000000
-/**
- * Interval for sending network size estimation flood requests.
- * Number is in milliseconds.
- * This needs to be a factor of the number milliseconds in
- * a day, as the base time used is midnight each day offset
- * by this amount.
- *
- * There are 86400000 milliseconds in a day.
- */
-#define GNUNET_NSE_INTERVAL 3600000 /* Once per hour */
-
-/**
- * Number of bits
- */
-#define GNUNET_NSE_BITS
-
/**
* Handle for the network size estimation service.
*/
struct GNUNET_NSE_Handle;
-
/**
* Callback to call when network size estimate is updated.
*
* @param cls closure
- * @param estimate the value of the current network size estimate
- * @param std_dev standard deviation (rounded down to nearest integer)
- * of the size estimation values seen
- * @return GNUNET_OK to continue, GNUNET_SYSERR to abort iteration
+ * @param timestamp time when the estimate was received from the server (or created by the server)
+ * @param logestimate the log(Base 2) value of the current network size estimate
+ * @param std_dev standard deviation for the estimate
+ *
*/
-typedef int
-(*GNUNET_NSE_Callback) (void *cls, double estimate, double std_dev);
+typedef void (*GNUNET_NSE_Callback) (void *cls,
+ struct GNUNET_TIME_Absolute timestamp,
+ double logestimate, double std_dev);
+
+
+/**
+ * Convert the logarithmic estimated returned to the 'GNUNET_NSE_Callback'
+ * into an absolute estimate in terms of the number of peers in the network.
+ *
+ * @param loge logarithmic estimate
+ * @return absolute number of peers in the network (estimated)
+ */
+#define GNUNET_NSE_log_estimate_to_n(loge) pow(2.0, (loge))
+
/**
* Connect to the network size estimation service.
*
* @param cfg the configuration to use
* @param func funtion to call with network size estimate
- * @param func_cls closure to pass for network size estimate callback
- *
- * @return handle to use
+ * @param func_cls closure to pass to @a func
+ * @return handle to use in #GNUNET_NSE_disconnect to stop NSE from invoking the callbacks
*/
struct GNUNET_NSE_Handle *
GNUNET_NSE_connect (const struct GNUNET_CONFIGURATION_Handle *cfg,
* Disconnect from network size estimation service
*
* @param h handle to destroy
- *
*/
void
GNUNET_NSE_disconnect (struct GNUNET_NSE_Handle *h);
}
#endif
+/** @} */ /* end of group nse */
+
#endif /* GNUNET_NSE_SERVICE_H_ */