/*
This file is part of GNUnet.
Copyright (C)
GNUnet is free software: you can redistribute it and/or modify it
under the terms of the GNU Affero General Public License as published
by the Free Software Foundation, either version 3 of the License,
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
Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program. If not, see .
SPDX-License-Identifier: AGPL3.0-or-later
*/
/**
* @file rps/rps-sampler_common.c
* @brief Code common to client and service sampler
* @author Julius Bünger
*/
#include "platform.h"
#include "gnunet_util_lib.h"
#include "gnunet_statistics_service.h"
#include "rps-sampler_common.h"
#include "gnunet-service-rps_sampler_elem.h"
#include
#include
#include "rps-test_util.h"
#define LOG(kind, ...) GNUNET_log_from (kind, "rps-sampler_common", __VA_ARGS__)
/**
* @brief Context for a callback. Contains callback and closure.
*
* Meant to be an entry in an DLL.
*/
struct SamplerNotifyUpdateCTX
{
/**
* @brief The Callback to call on updates
*/
SamplerNotifyUpdateCB notify_cb;
/**
* @brief The according closure.
*/
void *cls;
/**
* @brief Next element in DLL.
*/
struct SamplerNotifyUpdateCTX *next;
/**
* @brief Previous element in DLL.
*/
struct SamplerNotifyUpdateCTX *prev;
};
/**
* Closure to _get_n_rand_peers_ready_cb()
*/
struct RPS_SamplerRequestHandle
{
/**
* DLL
*/
struct RPS_SamplerRequestHandle *next;
struct RPS_SamplerRequestHandle *prev;
/**
* Number of peers we are waiting for.
*/
uint32_t num_peers;
/**
* Number of peers we currently have.
*/
uint32_t cur_num_peers;
/**
* Pointer to the array holding the ids.
*/
struct GNUNET_PeerIdentity *ids;
/**
* Head and tail for the DLL to store the tasks for single requests
*/
struct GetPeerCls *gpc_head;
struct GetPeerCls *gpc_tail;
/**
* Sampler.
*/
struct RPS_Sampler *sampler;
/**
* Callback to be called when all ids are available.
*/
RPS_sampler_n_rand_peers_ready_cb callback;
/**
* Closure given to the callback
*/
void *cls;
};
/**
* Closure to _get_rand_peer_info()
*/
struct RPS_SamplerRequestHandleSingleInfo
{
/**
* DLL
*/
struct RPS_SamplerRequestHandleSingleInfo *next;
struct RPS_SamplerRequestHandleSingleInfo *prev;
/**
* Pointer to the id
*/
struct GNUNET_PeerIdentity *id;
/**
* Head and tail for the DLL to store the tasks for single requests
*/
struct GetPeerCls *gpc_head;
struct GetPeerCls *gpc_tail;
/**
* Sampler.
*/
struct RPS_Sampler *sampler;
/**
* Callback to be called when all ids are available.
*/
RPS_sampler_sinlge_info_ready_cb callback;
/**
* Closure given to the callback
*/
void *cls;
};
/**
* @brief Update the current estimate of the network size stored at the sampler
*
* Used for computing the condition when to return elements to the client
*
* Only used/useful with the client sampler
* (Maybe move to rps-sampler_client.{h|c} ?)
*
* @param sampler The sampler to update
* @param num_peers The estimated value
*/
void
RPS_sampler_update_with_nw_size (struct RPS_Sampler *sampler,
uint32_t num_peers)
{
sampler->num_peers_estim = num_peers;
}
/**
* @brief Set the probability that is needed at least with what a sampler
* element has to have observed all elements from the network.
*
* Only used/useful with the client sampler
* (Maybe move to rps-sampler_client.{h|c} ?)
*
* @param sampler
* @param desired_probability
*/
void
RPS_sampler_set_desired_probability (struct RPS_Sampler *sampler,
double desired_probability)
{
sampler->desired_probability = desired_probability;
}
/**
* @brief Set the deficiency factor.
*
* Only used/useful with the client sampler
* (Maybe move to rps-sampler_client.{h|c} ?)
*
* @param sampler
* @param desired_probability
*/
void
RPS_sampler_set_deficiency_factor (struct RPS_Sampler *sampler,
double deficiency_factor)
{
sampler->deficiency_factor = deficiency_factor;
}
/**
* @brief Add a callback that will be called when the next peer is inserted
* into the sampler
*
* @param sampler The sampler on which update it will be called
* @param notify_cb The callback
* @param cls Closure given to the callback
*
* @return The context containing callback and closure
*/
struct SamplerNotifyUpdateCTX *
sampler_notify_on_update (struct RPS_Sampler *sampler,
SamplerNotifyUpdateCB notify_cb,
void *cls)
{
struct SamplerNotifyUpdateCTX *notify_ctx;
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Inserting new context for notification\n");
notify_ctx = GNUNET_new (struct SamplerNotifyUpdateCTX);
notify_ctx->notify_cb = notify_cb;
notify_ctx->cls = cls;
GNUNET_CONTAINER_DLL_insert (sampler->notify_ctx_head,
sampler->notify_ctx_tail,
notify_ctx);
return notify_ctx;
}
/**
* Get the size of the sampler.
*
* @param sampler the sampler to return the size of.
* @return the size of the sampler
*/
unsigned int
RPS_sampler_get_size (struct RPS_Sampler *sampler)
{
return sampler->sampler_size;
}
/**
* @brief Notify about update of the sampler.
*
* Call the callbacks that are waiting for notification on updates to the
* sampler.
*
* @param sampler The sampler the updates are waiting for
*/
static void
notify_update (struct RPS_Sampler *sampler)
{
struct SamplerNotifyUpdateCTX *tmp_notify_head;
struct SamplerNotifyUpdateCTX *tmp_notify_tail;
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Calling callbacks waiting for update notification.\n");
tmp_notify_head = sampler->notify_ctx_head;
tmp_notify_tail = sampler->notify_ctx_tail;
sampler->notify_ctx_head = NULL;
sampler->notify_ctx_tail = NULL;
for (struct SamplerNotifyUpdateCTX *notify_iter = tmp_notify_head;
NULL != tmp_notify_head;
notify_iter = tmp_notify_head)
{
GNUNET_assert (NULL != notify_iter->notify_cb);
GNUNET_CONTAINER_DLL_remove (tmp_notify_head,
tmp_notify_tail,
notify_iter);
notify_iter->notify_cb (notify_iter->cls);
GNUNET_free (notify_iter);
}
}
/**
* Update every sampler element of this sampler with given peer
*
* @param sampler the sampler to update.
* @param id the PeerID that is put in the sampler
*/
void
RPS_sampler_update (struct RPS_Sampler *sampler,
const struct GNUNET_PeerIdentity *id)
{
for (uint32_t i = 0; i < sampler->sampler_size; i++)
{
RPS_sampler_elem_next (sampler->sampler_elements[i],
id);
}
notify_update (sampler);
}
/**
* Reinitialise all previously initialised sampler elements with the given value.
*
* Used to get rid of a PeerID.
*
* FIXME: This should also consider currently pending requests
* (Pending requests already collect peerids. As long as not all
* requested IDs have been collected, they are kept.
* Ideally, the @p id should be removed from all pending requests. This
* seems quite complicated.)
*
* @param sampler the sampler to reinitialise a sampler element in.
* @param id the id of the sampler elements to update.
*/
void
RPS_sampler_reinitialise_by_value (struct RPS_Sampler *sampler,
const struct GNUNET_PeerIdentity *id)
{
uint32_t i;
for (i = 0; i < sampler->sampler_size; i++)
{
if (0 == GNUNET_memcmp (id,
&(sampler->sampler_elements[i]->peer_id)))
{
LOG (GNUNET_ERROR_TYPE_DEBUG, "Reinitialising sampler\n");
RPS_sampler_elem_reinit (sampler->sampler_elements[i]);
}
}
}
/**
* Counts how many Samplers currently hold a given PeerID.
*
* @param sampler the sampler to count ids in.
* @param id the PeerID to count.
*
* @return the number of occurrences of id.
*/
uint32_t
RPS_sampler_count_id (struct RPS_Sampler *sampler,
const struct GNUNET_PeerIdentity *id)
{
uint32_t count;
uint32_t i;
count = 0;
for (i = 0; i < sampler->sampler_size; i++)
{
if ((0 == GNUNET_memcmp (&sampler->sampler_elements[i]->peer_id, id))
&& (EMPTY != sampler->sampler_elements[i]->is_empty) )
count++;
}
return count;
}
/**
* Grow or shrink the size of the sampler.
*
* @param sampler the sampler to resize.
* @param new_size the new size of the sampler
*/
static void
sampler_resize (struct RPS_Sampler *sampler, unsigned int new_size)
{
unsigned int old_size;
uint32_t i;
// TODO check min and max size
old_size = sampler->sampler_size;
if (old_size > new_size)
{ /* Shrinking */
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Shrinking sampler %d -> %d\n",
old_size,
new_size);
for (i = new_size; i < old_size; i++)
{
RPS_sampler_elem_destroy (sampler->sampler_elements[i]);
}
GNUNET_array_grow (sampler->sampler_elements,
sampler->sampler_size,
new_size);
LOG (GNUNET_ERROR_TYPE_DEBUG,
"sampler->sampler_elements now points to %p\n",
sampler->sampler_elements);
}
else if (old_size < new_size)
{ /* Growing */
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Growing sampler %d -> %d\n",
old_size,
new_size);
GNUNET_array_grow (sampler->sampler_elements,
sampler->sampler_size,
new_size);
for (i = old_size; i < new_size; i++)
{ /* Add new sampler elements */
sampler->sampler_elements[i] = RPS_sampler_elem_create ();
}
}
else
{
LOG (GNUNET_ERROR_TYPE_DEBUG, "Size remains the same -- nothing to do\n");
return;
}
GNUNET_assert (sampler->sampler_size == new_size);
}
/**
* Grow or shrink the size of the sampler.
*
* @param sampler the sampler to resize.
* @param new_size the new size of the sampler
*/
void
RPS_sampler_resize (struct RPS_Sampler *sampler, unsigned int new_size)
{
GNUNET_assert (0 < new_size);
sampler_resize (sampler, new_size);
}
/**
* Empty the sampler.
*
* @param sampler the sampler to empty.
* @param new_size the new size of the sampler
*/
static void
sampler_empty (struct RPS_Sampler *sampler)
{
sampler_resize (sampler, 0);
}
/**
* Callback to _get_rand_peer() used by _get_n_rand_peers().
*
* Implements #RPS_sampler_rand_peer_ready_cont
*
* Checks whether all n peers are available. If they are,
* give those back.
* @param cls Closure
* @param id Peer ID
* @param probability The probability with which this sampler has seen all ids
* @param num_observed How many ids this sampler has observed
*/
static void
check_n_peers_ready (void *cls,
const struct GNUNET_PeerIdentity *id,
double probability,
uint32_t num_observed)
{
struct RPS_SamplerRequestHandle *req_handle = cls;
(void) id;
RPS_sampler_n_rand_peers_ready_cb tmp_cb;
struct GNUNET_PeerIdentity *peers;
uint32_t num_peers;
void *cb_cls;
(void) probability;
(void) num_observed;
req_handle->cur_num_peers++;
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Got %" PRIX32 ". of %" PRIX32 " peers\n",
req_handle->cur_num_peers, req_handle->num_peers);
if (req_handle->num_peers == req_handle->cur_num_peers)
{ /* All peers are ready -- return those to the client */
GNUNET_assert (NULL != req_handle->callback);
LOG (GNUNET_ERROR_TYPE_DEBUG,
"returning %" PRIX32 " peers to the client\n",
req_handle->num_peers);
/* Copy pointers and peers temporarily as they
* might be deleted from within the callback */
tmp_cb = req_handle->callback;
num_peers = req_handle->num_peers;
peers = GNUNET_new_array (num_peers, struct GNUNET_PeerIdentity);
GNUNET_memcpy (peers,
req_handle->ids,
num_peers * sizeof(struct GNUNET_PeerIdentity));
cb_cls = req_handle->cls;
RPS_sampler_request_cancel (req_handle);
req_handle = NULL;
tmp_cb (peers, num_peers, cb_cls);
GNUNET_free (peers);
}
}
/**
* Callback to _get_rand_peer() used by _get_rand_peer_info().
*
* Implements #RPS_sampler_rand_peer_ready_cont
*
* @param cls Closure
* @param id Peer ID
* @param probability The probability with which this sampler has seen all ids
* @param num_observed How many ids this sampler has observed
*/
static void
check_peer_info_ready (void *cls,
const struct GNUNET_PeerIdentity *id,
double probability,
uint32_t num_observed)
{
struct RPS_SamplerRequestHandleSingleInfo *req_handle = cls;
(void) id;
RPS_sampler_sinlge_info_ready_cb tmp_cb;
struct GNUNET_PeerIdentity *peer;
void *cb_cls;
(void) probability;
(void) num_observed;
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Got single peer with additional info\n");
GNUNET_assert (NULL != req_handle->callback);
LOG (GNUNET_ERROR_TYPE_DEBUG,
"returning single peer with info to the client\n");
/* Copy pointers and peers temporarily as they
* might be deleted from within the callback */
tmp_cb = req_handle->callback;
peer = GNUNET_new (struct GNUNET_PeerIdentity);
GNUNET_memcpy (peer,
req_handle->id,
sizeof(struct GNUNET_PeerIdentity));
cb_cls = req_handle->cls;
RPS_sampler_request_single_info_cancel (req_handle);
req_handle = NULL;
tmp_cb (peer, cb_cls, probability, num_observed);
GNUNET_free (peer);
}
/**
* Get n random peers out of the sampled peers.
*
* We might want to reinitialise this sampler after giving the
* corrsponding peer to the client.
* Random with or without consumption?
*
* @param sampler the sampler to get peers from.
* @param cb callback that will be called once the ids are ready.
* @param cls closure given to @a cb
* @param num_peers the number of peers requested
*/
struct RPS_SamplerRequestHandle *
RPS_sampler_get_n_rand_peers (struct RPS_Sampler *sampler,
uint32_t num_peers,
RPS_sampler_n_rand_peers_ready_cb cb,
void *cls)
{
uint32_t i;
struct RPS_SamplerRequestHandle *req_handle;
struct GetPeerCls *gpc;
GNUNET_assert (0 != sampler->sampler_size);
if (0 == num_peers)
return NULL;
// TODO check if we have too much (distinct) sampled peers
req_handle = GNUNET_new (struct RPS_SamplerRequestHandle);
req_handle->num_peers = num_peers;
req_handle->cur_num_peers = 0;
req_handle->ids = GNUNET_new_array (num_peers, struct GNUNET_PeerIdentity);
req_handle->sampler = sampler;
req_handle->callback = cb;
req_handle->cls = cls;
GNUNET_CONTAINER_DLL_insert (sampler->req_handle_head,
sampler->req_handle_tail,
req_handle);
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Scheduling requests for %" PRIu32 " peers\n", num_peers);
for (i = 0; i < num_peers; i++)
{
gpc = GNUNET_new (struct GetPeerCls);
gpc->req_handle = req_handle;
gpc->req_single_info_handle = NULL;
gpc->cont = check_n_peers_ready;
gpc->cont_cls = req_handle;
gpc->id = &req_handle->ids[i];
GNUNET_CONTAINER_DLL_insert (req_handle->gpc_head,
req_handle->gpc_tail,
gpc);
// maybe add a little delay
gpc->get_peer_task = GNUNET_SCHEDULER_add_now (sampler->get_peers,
gpc);
}
return req_handle;
}
/**
* Get one random peer with additional information.
*
* @param sampler the sampler to get peers from.
* @param cb callback that will be called once the ids are ready.
* @param cls closure given to @a cb
*/
struct RPS_SamplerRequestHandleSingleInfo *
RPS_sampler_get_rand_peer_info (struct RPS_Sampler *sampler,
RPS_sampler_sinlge_info_ready_cb cb,
void *cls)
{
struct RPS_SamplerRequestHandleSingleInfo *req_handle;
struct GetPeerCls *gpc;
GNUNET_assert (0 != sampler->sampler_size);
// TODO check if we have too much (distinct) sampled peers
req_handle = GNUNET_new (struct RPS_SamplerRequestHandleSingleInfo);
req_handle->id = GNUNET_malloc (sizeof(struct GNUNET_PeerIdentity));
req_handle->sampler = sampler;
req_handle->callback = cb;
req_handle->cls = cls;
GNUNET_CONTAINER_DLL_insert (sampler->req_handle_single_head,
sampler->req_handle_single_tail,
req_handle);
gpc = GNUNET_new (struct GetPeerCls);
gpc->req_handle = NULL;
gpc->req_single_info_handle = req_handle;
gpc->cont = check_peer_info_ready;
gpc->cont_cls = req_handle;
gpc->id = req_handle->id;
GNUNET_CONTAINER_DLL_insert (req_handle->gpc_head,
req_handle->gpc_tail,
gpc);
// maybe add a little delay
gpc->get_peer_task = GNUNET_SCHEDULER_add_now (sampler->get_peers,
gpc);
return req_handle;
}
/**
* Cancle a request issued through #RPS_sampler_n_rand_peers_ready_cb.
*
* @param req_handle the handle to the request
*/
void
RPS_sampler_request_cancel (struct RPS_SamplerRequestHandle *req_handle)
{
struct GetPeerCls *i;
while (NULL != (i = req_handle->gpc_head))
{
GNUNET_CONTAINER_DLL_remove (req_handle->gpc_head,
req_handle->gpc_tail,
i);
if (NULL != i->get_peer_task)
{
GNUNET_SCHEDULER_cancel (i->get_peer_task);
}
if (NULL != i->notify_ctx)
{
GNUNET_CONTAINER_DLL_remove (req_handle->sampler->notify_ctx_head,
req_handle->sampler->notify_ctx_tail,
i->notify_ctx);
GNUNET_free (i->notify_ctx);
i->notify_ctx = NULL;
}
GNUNET_free (i);
}
GNUNET_free (req_handle->ids);
req_handle->ids = NULL;
GNUNET_CONTAINER_DLL_remove (req_handle->sampler->req_handle_head,
req_handle->sampler->req_handle_tail,
req_handle);
GNUNET_free (req_handle);
}
/**
* Cancle a request issued through #RPS_sampler_sinlge_info_ready_cb.
*
* @param req_handle the handle to the request
*/
void
RPS_sampler_request_single_info_cancel (
struct RPS_SamplerRequestHandleSingleInfo *req_single_info_handle)
{
struct GetPeerCls *i;
while (NULL != (i = req_single_info_handle->gpc_head))
{
GNUNET_CONTAINER_DLL_remove (req_single_info_handle->gpc_head,
req_single_info_handle->gpc_tail,
i);
if (NULL != i->get_peer_task)
{
GNUNET_SCHEDULER_cancel (i->get_peer_task);
}
if (NULL != i->notify_ctx)
{
GNUNET_CONTAINER_DLL_remove (
req_single_info_handle->sampler->notify_ctx_head,
req_single_info_handle->sampler->
notify_ctx_tail,
i->notify_ctx);
GNUNET_free (i->notify_ctx);
i->notify_ctx = NULL;
}
GNUNET_free (i);
}
GNUNET_free (req_single_info_handle->id);
req_single_info_handle->id = NULL;
GNUNET_CONTAINER_DLL_remove (
req_single_info_handle->sampler->req_handle_single_head,
req_single_info_handle->sampler->
req_handle_single_tail,
req_single_info_handle);
GNUNET_free (req_single_info_handle);
}
/**
* Cleans the sampler.
*/
void
RPS_sampler_destroy (struct RPS_Sampler *sampler)
{
if (NULL != sampler->req_handle_head)
{
LOG (GNUNET_ERROR_TYPE_WARNING,
"There are still pending requests. Going to remove them.\n");
while (NULL != sampler->req_handle_head)
{
RPS_sampler_request_cancel (sampler->req_handle_head);
}
}
sampler_empty (sampler);
GNUNET_free (sampler);
}
/* end of rps-sampler_common.c */