Split sampler into common, sampler and client part

Now there is rps-sampler_client.{c|h} and
gnunet-service-rps_sampler.{c|h} to better reflect which parts are
really in the implementation of brahms (only the service) and which are
used in the client.
The parts both samplers share are now in rps-sampler_common.{c|h}.

1 files changed, 2 insertions, 646 deletions

diff --git a/src/rps/gnunet-service-rps_sampler.c b/src/rps/gnunet-service-rps_sampler.c
index 2cd4cb996..9629a29a1 100644
--- a/src/rps/gnunet-service-rps_sampler.c
+++ b/src/rps/gnunet-service-rps_sampler.c
@@ -26,6 +26,7 @@
 #include "gnunet_statistics_service.h"
 #include "rps.h"
 
+#include "rps-sampler_common.h"
 #include "gnunet-service-rps_sampler.h"
 #include "gnunet-service-rps_sampler_elem.h"
 
@@ -53,17 +54,6 @@
 // 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);
-
-
-/**
  * @brief Callback called each time a new peer was put into the sampler
  *
  * @param cls A possibly given closure
@@ -101,49 +91,6 @@ struct SamplerNotifyUpdateCTX
 
 
 /**
- * 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;
-
-  /**
-   * @brief Context to the given callback.
-   */
-  struct SamplerNotifyUpdateCTX *notify_ctx;
-
-  /**
-   * 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.
  */
@@ -162,61 +109,6 @@ 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;
-
-  struct SamplerNotifyUpdateCTX *notify_ctx_head;
-  struct SamplerNotifyUpdateCTX *notify_ctx_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
@@ -292,189 +184,6 @@ static uint32_t client_get_index;
 
 
 /**
- * @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;
-}
-
-
-/**
- * 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->ids, req_handle->num_peers, req_handle->cls);
-
-    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
@@ -514,119 +223,6 @@ RPS_sampler_init (size_t init_size,
 }
 
 /**
- * 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;
-}
-
-
-/**
- * @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)
-{
-  to_file (sampler->file_name,
-           "Got %s",
-           GNUNET_i2s_full (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.
- *
- * @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
@@ -658,7 +254,7 @@ sampler_get_rand_peer (void *cls)
 
     gpc->notify_ctx =
       sampler_notify_on_update (sampler,
-                                &sampler_mod_get_rand_peer,
+                                &sampler_get_rand_peer,
                                 gpc);
     return;
   }
@@ -673,244 +269,4 @@ sampler_get_rand_peer (void *cls)
 }
 
 
-/**
- * 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;
-  gpc->notify_ctx = 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->notify_ctx);
-    gpc->notify_ctx =
-      sampler_notify_on_update (sampler,
-                                &sampler_mod_get_rand_peer,
-                                gpc);
-    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)
-  {
-    // TODO remove this condition at least for the client sampler
-    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->notify_ctx);
-      gpc->notify_ctx =
-        sampler_notify_on_update (sampler,
-                                  &sampler_mod_get_rand_peer,
-                                  gpc);
-      return;
-    }
-  }
-  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->notify_ctx);
-    gpc->notify_ctx =
-      sampler_notify_on_update (sampler,
-                                &sampler_mod_get_rand_peer,
-                                gpc);
-    return;
-  }
-  /* 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,
-                              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->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);
-    }
-    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);
-    }
-    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 */