/*
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 .
*/
/**
* @file rps/gnunet-service-rps_sampler.c
* @brief sampler implementation
* @author Julius Bünger
*/
#include "platform.h"
#include "gnunet_util_lib.h"
#include "gnunet_statistics_service.h"
#include "rps.h"
#include "gnunet-service-rps_sampler.h"
#include "gnunet-service-rps_sampler_elem.h"
#include
#include
#include "rps-test_util.h"
#define LOG(kind, ...) GNUNET_log_from(kind,"rps-sampler",__VA_ARGS__)
// multiple 'clients'?
// TODO check for overflows
// TODO align message structs
// hist_size_init, hist_size_max
/***********************************************************************
* WARNING: This section needs to be reviewed regarding the use of
* functions providing (pseudo)randomness!
***********************************************************************/
// TODO care about invalid input of the caller (size 0 or less...)
/**
* Callback that is called from _get_rand_peer() when the PeerID is ready.
*
* @param cls the closure given alongside this function.
* @param id the PeerID that was returned
*/
typedef void
(*RPS_sampler_rand_peer_ready_cont) (void *cls,
const struct GNUNET_PeerIdentity *id);
/**
* Closure for #sampler_mod_get_rand_peer() and #sampler_get_rand_peer
*/
struct GetPeerCls
{
/**
* DLL
*/
struct GetPeerCls *next;
struct GetPeerCls *prev;
/**
* The #RPS_SamplerRequestHandle this single request belongs to.
*/
struct RPS_SamplerRequestHandle *req_handle;
/**
* The task for this function.
*/
struct GNUNET_SCHEDULER_Task *get_peer_task;
/**
* The callback
*/
RPS_sampler_rand_peer_ready_cont cont;
/**
* The closure to the callback @e cont
*/
void *cont_cls;
/**
* The address of the id to be stored at
*/
struct GNUNET_PeerIdentity *id;
};
/**
* Type of function used to differentiate between modified and not modified
* Sampler.
*/
typedef void
(*RPS_get_peers_type) (void *cls);
/**
* Get one random peer out of the sampled peers.
*
* We might want to reinitialise this sampler after giving the
* corrsponding peer to the client.
* Only used internally
*/
static void
sampler_get_rand_peer (void *cls);
/**
* Get one random peer out of the sampled peers.
*
* We might want to reinitialise this sampler after giving the
* corrsponding peer to the client.
*/
static void
sampler_mod_get_rand_peer (void *cls);
/**
* Sampler with its own array of SamplerElements
*/
struct RPS_Sampler
{
/**
* Number of sampler elements we hold.
*/
unsigned int sampler_size;
//size_t size;
/**
* All sampler elements in one array.
*/
struct RPS_SamplerElement **sampler_elements;
/**
* Maximum time a round takes
*
* Used in the context of RPS
*/
struct GNUNET_TIME_Relative max_round_interval;
/**
* Stores the function to return peers. Which one it is depends on whether
* the Sampler is the modified one or not.
*/
RPS_get_peers_type get_peers;
/**
* Head and tail for the DLL to store the #RPS_SamplerRequestHandle
*/
struct RPS_SamplerRequestHandle *req_handle_head;
struct RPS_SamplerRequestHandle *req_handle_tail;
#ifdef TO_FILE
/**
* File name to log to
*/
char *file_name;
#endif /* TO_FILE */
};
/**
* 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;
};
///**
// * Global sampler variable.
// */
//struct RPS_Sampler *sampler;
/**
* The minimal size for the extended sampler elements.
*/
static size_t min_size;
/**
* The maximal size the extended sampler elements should grow to.
*/
static size_t max_size;
/**
* The size the extended sampler elements currently have.
*/
//static size_t extra_size;
/**
* Inedex to the sampler element that is the next to be returned
*/
static uint32_t client_get_index;
/**
* Callback to _get_rand_peer() used by _get_n_rand_peers().
*
* Checks whether all n peers are available. If they are,
* give those back.
*/
static void
check_n_peers_ready (void *cls,
const struct GNUNET_PeerIdentity *id)
{
struct RPS_SamplerRequestHandle *req_handle = cls;
(void) id;
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);
req_handle->callback (req_handle->cls, req_handle->ids, req_handle->num_peers);
RPS_sampler_request_cancel (req_handle);
}
}
/**
* 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;
}
/**
* 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);
to_file (sampler->file_name,
"Shrinking sampler %d -> %d",
old_size,
new_size);
for (i = new_size ; i < old_size ; i++)
{
to_file (sampler->file_name,
"-%" PRIu32 ": %s",
i,
sampler->sampler_elements[i]->file_name);
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);
to_file (sampler->file_name,
"Growing sampler %d -> %d",
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 ();
to_file (sampler->file_name,
"+%" PRIu32 ": %s",
i,
sampler->sampler_elements[i]->file_name);
}
}
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);
}
/**
* Initialise a tuple of sampler elements.
*
* @param init_size the size the sampler is initialised with
* @param max_round_interval maximum time a round takes
* @return a handle to a sampler that consists of sampler elements.
*/
struct RPS_Sampler *
RPS_sampler_init (size_t init_size,
struct GNUNET_TIME_Relative max_round_interval)
{
struct RPS_Sampler *sampler;
/* Initialise context around extended sampler */
min_size = 10; // TODO make input to _samplers_init()
max_size = 1000; // TODO make input to _samplers_init()
sampler = GNUNET_new (struct RPS_Sampler);
#ifdef TO_FILE
sampler->file_name = create_file ("sampler-");
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Initialised sampler %s\n",
sampler->file_name);
#endif /* TO_FILE */
sampler->max_round_interval = max_round_interval;
sampler->get_peers = sampler_get_rand_peer;
//sampler->sampler_elements = GNUNET_new_array(init_size, struct GNUNET_PeerIdentity);
//GNUNET_array_grow (sampler->sampler_elements, sampler->sampler_size, min_size);
RPS_sampler_resize (sampler, init_size);
client_get_index = 0;
//GNUNET_assert (init_size == sampler->sampler_size);
return sampler;
}
/**
* Initialise a modified tuple of sampler elements.
*
* @param init_size the size the sampler is initialised with
* @param max_round_interval maximum time a round takes
* @return a handle to a sampler that consists of sampler elements.
*/
struct RPS_Sampler *
RPS_sampler_mod_init (size_t init_size,
struct GNUNET_TIME_Relative max_round_interval)
{
struct RPS_Sampler *sampler;
sampler = RPS_sampler_init (init_size, max_round_interval);
sampler->get_peers = sampler_mod_get_rand_peer;
#ifdef TO_FILE
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Initialised modified sampler %s\n",
sampler->file_name);
to_file (sampler->file_name,
"This is a modified sampler");
#endif /* TO_FILE */
return sampler;
}
/**
* A fuction to update every sampler in the given list
*
* @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)
{
uint32_t i;
to_file (sampler->file_name,
"Got %s",
GNUNET_i2s_full (id));
for (i = 0; i < sampler->sampler_size; i++)
{
RPS_sampler_elem_next (sampler->sampler_elements[i],
id);
}
}
/**
* Reinitialise all previously initialised sampler elements with the given value.
*
* Used to get rid of a PeerID.
*
* @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_CRYPTO_cmp_peer_identity(id,
&(sampler->sampler_elements[i]->peer_id)) )
{
LOG (GNUNET_ERROR_TYPE_DEBUG, "Reinitialising sampler\n");
to_file (sampler->sampler_elements[i]->file_name,
"--- non-active");
RPS_sampler_elem_reinit (sampler->sampler_elements[i]);
}
}
}
/**
* Get one random peer out of the sampled peers.
*
* We might want to reinitialise this sampler after giving the
* corrsponding peer to the client.
* Only used internally
*/
static void
sampler_get_rand_peer (void *cls)
{
struct GetPeerCls *gpc = cls;
uint32_t r_index;
struct RPS_Sampler *sampler;
gpc->get_peer_task = NULL;
sampler = gpc->req_handle->sampler;
/**;
* Choose the r_index of the peer we want to return
* at random from the interval of the gossip list
*/
r_index = GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_STRONG,
sampler->sampler_size);
if (EMPTY == sampler->sampler_elements[r_index]->is_empty)
{
//LOG (GNUNET_ERROR_TYPE_DEBUG,
// "Not returning randomly selected, empty PeerID. - Rescheduling.\n");
/* FIXME no active wait - get notified, when new id arrives?
* Might also be a freshly emptied one. Others might still contain ids.
* Counter?
*/
gpc->get_peer_task =
GNUNET_SCHEDULER_add_delayed (
GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 1),
&sampler_get_rand_peer,
cls);
return;
}
GNUNET_CONTAINER_DLL_remove (gpc->req_handle->gpc_head,
gpc->req_handle->gpc_tail,
gpc);
*gpc->id = sampler->sampler_elements[r_index]->peer_id;
gpc->cont (gpc->cont_cls, gpc->id);
GNUNET_free (gpc);
}
/**
* Get one random peer out of the sampled peers.
*
* This reinitialises the queried sampler element.
*/
static void
sampler_mod_get_rand_peer (void *cls)
{
struct GetPeerCls *gpc = cls;
struct RPS_SamplerElement *s_elem;
struct GNUNET_TIME_Relative last_request_diff;
struct RPS_Sampler *sampler;
gpc->get_peer_task = NULL;
sampler = gpc->req_handle->sampler;
LOG (GNUNET_ERROR_TYPE_DEBUG, "Single peer was requested\n");
/* Cycle the #client_get_index one step further */
client_get_index = (client_get_index + 1) % sampler->sampler_size;
s_elem = sampler->sampler_elements[client_get_index];
*gpc->id = s_elem->peer_id;
GNUNET_assert (NULL != s_elem);
if (EMPTY == s_elem->is_empty)
{
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Sampler_mod element empty, rescheduling.\n");
GNUNET_assert (NULL == gpc->get_peer_task);
gpc->get_peer_task =
GNUNET_SCHEDULER_add_delayed (sampler->max_round_interval,
&sampler_mod_get_rand_peer,
cls);
return;
}
/* Check whether we may use this sampler to give it back to the client */
if (GNUNET_TIME_UNIT_FOREVER_ABS.abs_value_us != s_elem->last_client_request.abs_value_us)
{
last_request_diff =
GNUNET_TIME_absolute_get_difference (s_elem->last_client_request,
GNUNET_TIME_absolute_get ());
/* We're not going to give it back now if it was
* already requested by a client this round */
if (last_request_diff.rel_value_us < sampler->max_round_interval.rel_value_us)
{
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Last client request on this sampler was less than max round interval ago -- scheduling for later\n");
///* How many time remains untile the next round has started? */
//inv_last_request_diff =
// GNUNET_TIME_absolute_get_difference (last_request_diff,
// sampler->max_round_interval);
// add a little delay
/* Schedule it one round later */
GNUNET_assert (NULL == gpc->get_peer_task);
gpc->get_peer_task =
GNUNET_SCHEDULER_add_delayed (sampler->max_round_interval,
&sampler_mod_get_rand_peer,
cls);
return;
}
else if (2 < s_elem->num_peers)
{
LOG (GNUNET_ERROR_TYPE_DEBUG,
"This s_elem saw less than two peers -- scheduling for later\n");
GNUNET_assert (NULL == gpc->get_peer_task);
gpc->get_peer_task =
GNUNET_SCHEDULER_add_delayed (sampler->max_round_interval,
&sampler_mod_get_rand_peer,
cls);
}
/* More reasons to wait could be added here */
}
GNUNET_STATISTICS_set (stats,
"# client sampler element input",
s_elem->num_peers,
GNUNET_NO);
GNUNET_STATISTICS_set (stats,
"# client sampler element change",
s_elem->num_change,
GNUNET_NO);
RPS_sampler_elem_reinit (s_elem);
s_elem->last_client_request = GNUNET_TIME_absolute_get ();
GNUNET_CONTAINER_DLL_remove (gpc->req_handle->gpc_head,
gpc->req_handle->gpc_tail,
gpc);
gpc->cont (gpc->cont_cls, gpc->id);
GNUNET_free (gpc);
}
/**
* 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 for_client #GNUNET_YES if result is used for client,
* #GNUNET_NO if used internally
* @param num_peers the number of peers requested
*/
struct RPS_SamplerRequestHandle *
RPS_sampler_get_n_rand_peers (struct RPS_Sampler *sampler,
RPS_sampler_n_rand_peers_ready_cb cb,
void *cls, uint32_t num_peers)
{
GNUNET_assert (0 != sampler->sampler_size);
if (0 == num_peers)
return NULL;
// TODO check if we have too much (distinct) sampled peers
uint32_t i;
struct RPS_SamplerRequestHandle *req_handle;
struct GetPeerCls *gpc;
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->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;
}
/**
* 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);
}
GNUNET_free (i);
}
GNUNET_free (req_handle->ids);
GNUNET_CONTAINER_DLL_remove (req_handle->sampler->req_handle_head,
req_handle->sampler->req_handle_tail,
req_handle);
GNUNET_free (req_handle);
}
/**
* 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_CRYPTO_cmp_peer_identity (&sampler->sampler_elements[i]->peer_id, id)
&& EMPTY != sampler->sampler_elements[i]->is_empty)
count++;
}
return count;
}
/**
* 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 gnunet-service-rps.c */