uncrustify as demanded.
[oweals/gnunet.git] / src / datacache / plugin_datacache_heap.c
index 85cf9487ef801eb81f6fbbf171c9456f9232e1d0..face566a17a20af320dd7629924901f82faa6d0d 100644 (file)
@@ -1,22 +1,22 @@
 /*
      This file is part of GNUnet
-     (C) 2012 Christian Grothoff (and other contributing authors)
+     Copyright (C) 2012, 2015 GNUnet e.V.
 
-     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 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
-     General Public License for more details.
+     Affero 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.
-*/
+     You should have received a copy of the GNU Affero General Public License
+     along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+     SPDX-License-Identifier: AGPL3.0-or-later
+ */
 
 /**
  * @file datacache/plugin_datacache_heap.c
 #include "gnunet_util_lib.h"
 #include "gnunet_datacache_plugin.h"
 
-#define LOG(kind,...) GNUNET_log_from (kind, "datacache-heap", __VA_ARGS__)
-
-#define LOG_STRERROR_FILE(kind,op,fn) GNUNET_log_from_strerror_file (kind, "datacache-heap", op, fn)
+#define LOG(kind, ...) GNUNET_log_from(kind, "datacache-heap", __VA_ARGS__)
 
+#define LOG_STRERROR_FILE(kind, op, fn) GNUNET_log_from_strerror_file(kind, "datacache-heap", op, fn)
 
+#define NUM_HEAPS 24
 
 /**
  * Context for all functions in this plugin.
  */
-struct Plugin
-{
+struct Plugin {
   /**
    * Our execution environment.
    */
@@ -49,18 +48,16 @@ struct Plugin
   struct GNUNET_CONTAINER_MultiHashMap *map;
 
   /**
-   * Heap for expirations.
+   * Heaps sorted by distance.
    */
-  struct GNUNET_CONTAINER_Heap *heap;
-
+  struct GNUNET_CONTAINER_Heap *heaps[NUM_HEAPS];
 };
 
 
 /**
  * Entry in the hash map.
  */
-struct Value
-{
+struct Value {
   /**
    * Key for the entry.
    */
@@ -87,26 +84,29 @@ struct Value
   size_t size;
 
   /**
-   * Number of entries in 'path_info'.
+   * Number of entries in @e path_info.
    */
   unsigned int path_info_len;
 
+  /**
+   * How close is the hash to us? Determines which heap we are in!
+   */
+  uint32_t distance;
+
   /**
    * Type of the block.
    */
   enum GNUNET_BLOCK_Type type;
-
 };
 
 
-#define OVERHEAD (sizeof (struct Value) + 64)
+#define OVERHEAD (sizeof(struct Value) + 64)
 
 
 /**
- * Closure for 'put_cb'.
+ * Closure for #put_cb().
  */
-struct PutContext
-{
+struct PutContext {
   /**
    * Expiration time for the new value.
    */
@@ -117,18 +117,13 @@ struct PutContext
    */
   const char *data;
 
-  /**
-   * Heap from the plugin.
-   */
-  struct GNUNET_CONTAINER_Heap *heap;
-
   /**
    * Path information.
    */
   const struct GNUNET_PeerIdentity *path_info;
 
   /**
-   * Number of bytes in 'data'.
+   * Number of bytes in @e data.
    */
   size_t size;
 
@@ -138,12 +133,12 @@ struct PutContext
   enum GNUNET_BLOCK_Type type;
 
   /**
-   * Number of entries in 'path_info'.
+   * Number of entries in @e path_info.
    */
   unsigned int path_info_len;
 
   /**
-   * Value to set to GNUNET_YES if an equivalent block was found.
+   * Value to set to #GNUNET_YES if an equivalent block was found.
    */
   int found;
 };
@@ -153,44 +148,45 @@ struct PutContext
  * Function called during PUT to detect if an equivalent block
  * already exists.
  *
- * @param cls the 'struct PutContext'
+ * @param cls the `struct PutContext`
  * @param key the key for the value(s)
  * @param value an existing value
  * @return #GNUNET_YES if not found (to continue to iterate)
  */
 static int
-put_cb (void *cls,
-       const struct GNUNET_HashCode *key,
-       void *value)
+put_cb(void *cls,
+       const struct GNUNET_HashCode *key,
+       void *value)
 {
   struct PutContext *put_ctx = cls;
   struct Value *val = value;
 
-  if ( (val->size == put_ctx->size) &&
-       (val->type == put_ctx->type) &&
-       (0 == memcmp (&val[1], put_ctx->data, put_ctx->size)) )
-  {
-    put_ctx->found = GNUNET_YES;
-    val->discard_time = GNUNET_TIME_absolute_max (val->discard_time,
-                                                 put_ctx->discard_time);
-    /* replace old path with new path */
-    GNUNET_array_grow (val->path_info,
-                      val->path_info_len,
-                      put_ctx->path_info_len);
-    memcpy (val->path_info,
-           put_ctx->path_info,
-           put_ctx->path_info_len * sizeof (struct GNUNET_PeerIdentity));
-    GNUNET_CONTAINER_heap_update_cost (put_ctx->heap,
-                                      val->hn,
-                                      val->discard_time.abs_value_us);
-    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-               "Got same value for key %s and type %d (size %u vs %u)\n",
-               GNUNET_h2s (key),
-               val->type,
-               (unsigned int) val->size,
-               (unsigned int) put_ctx->size);
-    return GNUNET_NO;
-  }
+  if ((val->size == put_ctx->size) &&
+      (val->type == put_ctx->type) &&
+      (0 == memcmp(&val[1],
+                   put_ctx->data,
+                   put_ctx->size)))
+    {
+      put_ctx->found = GNUNET_YES;
+      val->discard_time = GNUNET_TIME_absolute_max(val->discard_time,
+                                                   put_ctx->discard_time);
+      /* replace old path with new path */
+      GNUNET_array_grow(val->path_info,
+                        val->path_info_len,
+                        put_ctx->path_info_len);
+      GNUNET_memcpy(val->path_info,
+                    put_ctx->path_info,
+                    put_ctx->path_info_len * sizeof(struct GNUNET_PeerIdentity));
+      GNUNET_CONTAINER_heap_update_cost(val->hn,
+                                        val->discard_time.abs_value_us);
+      GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+                 "Got same value for key %s and type %d (size %u vs %u)\n",
+                 GNUNET_h2s(key),
+                 val->type,
+                 (unsigned int)val->size,
+                 (unsigned int)put_ctx->size);
+      return GNUNET_NO;
+    }
   return GNUNET_YES;
 }
 
@@ -200,73 +196,83 @@ put_cb (void *cls,
  *
  * @param cls closure (our `struct Plugin`)
  * @param key key to store data under
- * @param size number of bytes in data
+ * @param xor_distance how close is @a key to our PID?
+ * @param size number of bytes in @a data
  * @param data data to store
  * @param type type of the value
  * @param discard_time when to discard the value in any case
  * @param path_info_len number of entries in @a path_info
  * @param path_info a path through the network
  * @return 0 if duplicate, -1 on error, number of bytes used otherwise
+ * @return 0 if duplicate, -1 on error, number of bytes used otherwise
  */
 static ssize_t
-heap_plugin_put (void *cls, const struct GNUNET_HashCode * key, size_t size,
-                const char *data, enum GNUNET_BLOCK_Type type,
-                struct GNUNET_TIME_Absolute discard_time,
-                unsigned int path_info_len,
-                const struct GNUNET_PeerIdentity *path_info)
+heap_plugin_put(void *cls,
+                const struct GNUNET_HashCode *key,
+                uint32_t xor_distance,
+                size_t size,
+                const char *data,
+                enum GNUNET_BLOCK_Type type,
+                struct GNUNET_TIME_Absolute discard_time,
+                unsigned int path_info_len,
+                const struct GNUNET_PeerIdentity *path_info)
 {
   struct Plugin *plugin = cls;
   struct Value *val;
   struct PutContext put_ctx;
 
   put_ctx.found = GNUNET_NO;
-  put_ctx.heap = plugin->heap;
   put_ctx.data = data;
   put_ctx.size = size;
   put_ctx.path_info = path_info;
   put_ctx.path_info_len = path_info_len;
   put_ctx.discard_time = discard_time;
   put_ctx.type = type;
-  GNUNET_CONTAINER_multihashmap_get_multiple (plugin->map,
-                                             key,
-                                             put_cb,
-                                             &put_ctx);
+  GNUNET_CONTAINER_multihashmap_get_multiple(plugin->map,
+                                             key,
+                                             &put_cb,
+                                             &put_ctx);
   if (GNUNET_YES == put_ctx.found)
     return 0;
-  val = GNUNET_malloc (sizeof (struct Value) + size);
-  memcpy (&val[1], data, size);
+  val = GNUNET_malloc(sizeof(struct Value) + size);
+  GNUNET_memcpy(&val[1],
+                data,
+                size);
   val->key = *key;
   val->type = type;
   val->discard_time = discard_time;
   val->size = size;
-  GNUNET_array_grow (val->path_info,
-                    val->path_info_len,
-                    path_info_len);
-  memcpy (val->path_info, path_info,
-         path_info_len * sizeof (struct GNUNET_PeerIdentity));
-  (void) GNUNET_CONTAINER_multihashmap_put (plugin->map,
-                                           &val->key,
-                                           val,
-                                           GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
-  val->hn = GNUNET_CONTAINER_heap_insert (plugin->heap,
-                                         val,
-                                         val->discard_time.abs_value_us);
+  if (xor_distance >= NUM_HEAPS)
+    val->distance = NUM_HEAPS - 1;
+  else
+    val->distance = xor_distance;
+  GNUNET_array_grow(val->path_info,
+                    val->path_info_len,
+                    path_info_len);
+  GNUNET_memcpy(val->path_info,
+                path_info,
+                path_info_len * sizeof(struct GNUNET_PeerIdentity));
+  (void)GNUNET_CONTAINER_multihashmap_put(plugin->map,
+                                          &val->key,
+                                          val,
+                                          GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
+  val->hn = GNUNET_CONTAINER_heap_insert(plugin->heaps[val->distance],
+                                         val,
+                                         val->discard_time.abs_value_us);
   return size + OVERHEAD;
 }
 
 
 /**
- * Closure for 'get_cb'.
+ * Closure for #get_cb().
  */
-struct GetContext
-{
+struct GetContext {
   /**
    * Function to call for each result.
    */
   GNUNET_DATACACHE_Iterator iter;
 
   /**
-   * Closure for 'iter'.
+   * Closure for @e iter.
    */
   void *iter_cls;
 
@@ -287,32 +293,35 @@ struct GetContext
  * Function called during GET to find matching blocks.
  * Only matches by type.
  *
- * @param cls the 'struct GetContext'
+ * @param cls the `struct GetContext`
  * @param key the key for the value(s)
  * @param value an existing value
- * @return GNUNET_YES to continue to iterate
+ * @return #GNUNET_YES to continue to iterate
  */
 static int
-get_cb (void *cls,
-       const struct GNUNET_HashCode *key,
-       void *value)
+get_cb(void *cls,
+       const struct GNUNET_HashCode *key,
+       void *value)
 {
   struct GetContext *get_ctx = cls;
   struct Value *val = value;
   int ret;
 
-  if ( (get_ctx->type != val->type) &&
-       (GNUNET_BLOCK_TYPE_ANY != get_ctx->type) )
+  if ((get_ctx->type != val->type) &&
+      (GNUNET_BLOCK_TYPE_ANY != get_ctx->type))
+    return GNUNET_OK;
+  if (0 ==
+      GNUNET_TIME_absolute_get_remaining(val->discard_time).rel_value_us)
     return GNUNET_OK;
   if (NULL != get_ctx->iter)
-    ret = get_ctx->iter (get_ctx->iter_cls,
-                        key,
-                        val->size,
-                        (const char *) &val[1],
-                        val->type,
-                      val->discard_time,
-                        val->path_info_len,
-                        val->path_info);
+    ret = get_ctx->iter(get_ctx->iter_cls,
+                        key,
+                        val->size,
+                        (const char *)&val[1],
+                        val->type,
+                        val->discard_time,
+                        val->path_info_len,
+                        val->path_info);
   else
     ret = GNUNET_YES;
   get_ctx->cnt++;
@@ -324,17 +333,19 @@ get_cb (void *cls,
  * Iterate over the results for a particular key
  * in the datastore.
  *
- * @param cls closure (our "struct Plugin")
+ * @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
+ * @param iter_cls closure for @a iter
  * @return the number of results found
  */
 static unsigned int
-heap_plugin_get (void *cls, const struct GNUNET_HashCode * key,
-                   enum GNUNET_BLOCK_Type type, GNUNET_DATACACHE_Iterator iter,
-                   void *iter_cls)
+heap_plugin_get(void *cls,
+                const struct GNUNET_HashCode *key,
+                enum GNUNET_BLOCK_Type type,
+                GNUNET_DATACACHE_Iterator iter,
+                void *iter_cls)
 {
   struct Plugin *plugin = cls;
   struct GetContext get_ctx;
@@ -343,10 +354,10 @@ heap_plugin_get (void *cls, const struct GNUNET_HashCode * key,
   get_ctx.iter = iter;
   get_ctx.iter_cls = iter_cls;
   get_ctx.cnt = 0;
-  GNUNET_CONTAINER_multihashmap_get_multiple (plugin->map,
-                                             key,
-                                             get_cb,
-                                             &get_ctx);
+  GNUNET_CONTAINER_multihashmap_get_multiple(plugin->map,
+                                             key,
+                                             &get_cb,
+                                             &get_ctx);
   return get_ctx.cnt;
 }
 
@@ -355,31 +366,157 @@ heap_plugin_get (void *cls, const struct GNUNET_HashCode * key,
  * Delete the entry with the lowest expiration value
  * from the datacache right now.
  *
- * @param cls closure (our "struct Plugin")
+ * @param cls closure (our `struct Plugin`)
  * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
  */
 static int
-heap_plugin_del (void *cls)
+heap_plugin_del(void *cls)
 {
   struct Plugin *plugin = cls;
   struct Value *val;
 
-  val = GNUNET_CONTAINER_heap_remove_root (plugin->heap);
+  for (unsigned int i = 0; i < NUM_HEAPS; i++)
+    {
+      val = GNUNET_CONTAINER_heap_remove_root(plugin->heaps[i]);
+      if (NULL != val)
+        break;
+    }
   if (NULL == val)
     return GNUNET_SYSERR;
-  GNUNET_assert (GNUNET_YES ==
-                GNUNET_CONTAINER_multihashmap_remove (plugin->map,
-                                                      &val->key,
-                                                      val));
-  plugin->env->delete_notify (plugin->env->cls,
-                             &val->key,
-                             val->size + OVERHEAD);
-  GNUNET_free_non_null (val->path_info);
-  GNUNET_free (val);
+  GNUNET_assert(GNUNET_YES ==
+                GNUNET_CONTAINER_multihashmap_remove(plugin->map,
+                                                     &val->key,
+                                                     val));
+  plugin->env->delete_notify(plugin->env->cls,
+                             &val->key,
+                             val->size + OVERHEAD);
+  GNUNET_free_non_null(val->path_info);
+  GNUNET_free(val);
   return GNUNET_OK;
 }
 
 
+/**
+ * Return a random value from the datastore.
+ *
+ * @param cls closure (our `struct Plugin`)
+ * @param iter maybe NULL (to just count)
+ * @param iter_cls closure for @a iter
+ * @return the number of results found
+ */
+static unsigned int
+heap_plugin_get_random(void *cls,
+                       GNUNET_DATACACHE_Iterator iter,
+                       void *iter_cls)
+{
+  struct Plugin *plugin = cls;
+  struct GetContext get_ctx;
+
+  get_ctx.type = GNUNET_BLOCK_TYPE_ANY;
+  get_ctx.iter = iter;
+  get_ctx.iter_cls = iter_cls;
+  get_ctx.cnt = 0;
+  GNUNET_CONTAINER_multihashmap_get_random(plugin->map,
+                                           &get_cb,
+                                           &get_ctx);
+  return get_ctx.cnt;
+}
+
+
+/**
+ * Closure for #find_closest().
+ */
+struct GetClosestContext {
+  struct Value **values;
+
+  unsigned int num_results;
+
+  const struct GNUNET_HashCode *key;
+};
+
+
+static int
+find_closest(void *cls,
+             const struct GNUNET_HashCode *key,
+             void *value)
+{
+  struct GetClosestContext *gcc = cls;
+  struct Value *val = value;
+  unsigned int j;
+
+  if (1 != GNUNET_CRYPTO_hash_cmp(key,
+                                  gcc->key))
+    return GNUNET_OK; /* useless */
+  j = gcc->num_results;
+  for (unsigned int i = 0; i < gcc->num_results; i++)
+    {
+      if (NULL == gcc->values[i])
+        {
+          j = i;
+          break;
+        }
+      if (1 == GNUNET_CRYPTO_hash_cmp(&gcc->values[i]->key,
+                                      key))
+        {
+          j = i;
+          break;
+        }
+    }
+  if (j == gcc->num_results)
+    return GNUNET_OK;
+  gcc->values[j] = val;
+  return GNUNET_OK;
+}
+
+
+/**
+ * Iterate over the results that are "close" to a particular key in
+ * the datacache.  "close" is defined as numerically larger than @a
+ * key (when interpreted as a circular address space), with small
+ * distance.
+ *
+ * @param cls closure (internal context for the plugin)
+ * @param key area of the keyspace to look into
+ * @param num_results number of results that should be returned to @a iter
+ * @param iter maybe NULL (to just count)
+ * @param iter_cls closure for @a iter
+ * @return the number of results found
+ */
+static unsigned int
+heap_plugin_get_closest(void *cls,
+                        const struct GNUNET_HashCode *key,
+                        unsigned int num_results,
+                        GNUNET_DATACACHE_Iterator iter,
+                        void *iter_cls)
+{
+  struct Plugin *plugin = cls;
+  struct Value *values[num_results];
+  struct GetClosestContext gcc = {
+    .values = values,
+    .num_results = num_results,
+    .key = key
+  };
+
+  GNUNET_CONTAINER_multihashmap_iterate(plugin->map,
+                                        &find_closest,
+                                        &gcc);
+  for (unsigned int i = 0; i < num_results; i++)
+    {
+      if (NULL == values[i])
+        return i;
+      iter(iter_cls,
+           &values[i]->key,
+           values[i]->size,
+           (void *)&values[i][1],
+           values[i]->type,
+           values[i]->discard_time,
+           values[i]->path_info_len,
+           values[i]->path_info);
+    }
+  return num_results;
+}
+
+
 /**
  * Entry point for the plugin.
  *
@@ -387,23 +524,27 @@ heap_plugin_del (void *cls)
  * @return the plugin's closure (our `struct Plugin`)
  */
 void *
-libgnunet_plugin_datacache_heap_init (void *cls)
+libgnunet_plugin_datacache_heap_init(void *cls)
 {
   struct GNUNET_DATACACHE_PluginEnvironment *env = cls;
   struct GNUNET_DATACACHE_PluginFunctions *api;
   struct Plugin *plugin;
 
-  plugin = GNUNET_malloc (sizeof (struct Plugin));
-  plugin->map = GNUNET_CONTAINER_multihashmap_create (1024,  /* FIXME: base on quota! */
-                                                     GNUNET_YES);
-  plugin->heap = GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
+  plugin = GNUNET_new(struct Plugin);
+  plugin->map = GNUNET_CONTAINER_multihashmap_create(1024,   /* FIXME: base on quota! */
+                                                     GNUNET_YES);
+  for (unsigned int i = 0; i < NUM_HEAPS; i++)
+    plugin->heaps[i] = GNUNET_CONTAINER_heap_create(GNUNET_CONTAINER_HEAP_ORDER_MIN);
   plugin->env = env;
-  api = GNUNET_malloc (sizeof (struct GNUNET_DATACACHE_PluginFunctions));
+  api = GNUNET_new(struct GNUNET_DATACACHE_PluginFunctions);
   api->cls = plugin;
   api->get = &heap_plugin_get;
   api->put = &heap_plugin_put;
   api->del = &heap_plugin_del;
-  LOG (GNUNET_ERROR_TYPE_INFO, _("Heap datacache running\n"));
+  api->get_random = &heap_plugin_get_random;
+  api->get_closest = &heap_plugin_get_closest;
+  LOG(GNUNET_ERROR_TYPE_INFO,
+      _("Heap datacache running\n"));
   return api;
 }
 
@@ -415,25 +556,28 @@ libgnunet_plugin_datacache_heap_init (void *cls)
  * @return NULL
  */
 void *
-libgnunet_plugin_datacache_heap_done (void *cls)
+libgnunet_plugin_datacache_heap_done(void *cls)
 {
   struct GNUNET_DATACACHE_PluginFunctions *api = cls;
   struct Plugin *plugin = api->cls;
   struct Value *val;
 
-  while (NULL != (val = GNUNET_CONTAINER_heap_remove_root (plugin->heap)))
-  {
-    GNUNET_assert (GNUNET_YES ==
-                  GNUNET_CONTAINER_multihashmap_remove (plugin->map,
-                                                        &val->key,
-                                                        val));
-    GNUNET_free_non_null (val->path_info);
-    GNUNET_free (val);
-  }
-  GNUNET_CONTAINER_heap_destroy (plugin->heap);
-  GNUNET_CONTAINER_multihashmap_destroy (plugin->map);
-  GNUNET_free (plugin);
-  GNUNET_free (api);
+  for (unsigned int i = 0; i < NUM_HEAPS; i++)
+    {
+      while (NULL != (val = GNUNET_CONTAINER_heap_remove_root(plugin->heaps[i])))
+        {
+          GNUNET_assert(GNUNET_YES ==
+                        GNUNET_CONTAINER_multihashmap_remove(plugin->map,
+                                                             &val->key,
+                                                             val));
+          GNUNET_free_non_null(val->path_info);
+          GNUNET_free(val);
+        }
+      GNUNET_CONTAINER_heap_destroy(plugin->heaps[i]);
+    }
+  GNUNET_CONTAINER_multihashmap_destroy(plugin->map);
+  GNUNET_free(plugin);
+  GNUNET_free(api);
   return NULL;
 }