Link libgnunetblockgroup to libgnunetblock
[oweals/gnunet.git] / src / block / block.c
index bc597739e0dc215ce1dfb2f9e692d8e662e42f43..23caacd382f37a97d4c539361e1a1e213891abfa 100644 (file)
@@ -1,6 +1,6 @@
 /*
      This file is part of GNUnet.
-     (C) 2010 Christian Grothoff (and other contributing authors)
+     Copyright (C) 2010, 2017 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
@@ -14,8 +14,8 @@
 
      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.
+     Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+     Boston, MA 02110-1301, USA.
 */
 
 /**
@@ -25,6 +25,7 @@
  */
 #include "platform.h"
 #include "gnunet_util_lib.h"
+#include "gnunet_constants.h"
 #include "gnunet_signatures.h"
 #include "gnunet_block_lib.h"
 #include "gnunet_block_plugin.h"
@@ -37,9 +38,9 @@ struct Plugin
 {
   /**
    * Name of the shared library.
-   */ 
+   */
   char *library_name;
-  
+
   /**
    * Plugin API.
    */
@@ -53,38 +54,74 @@ struct Plugin
 struct GNUNET_BLOCK_Context
 {
   /**
-   * NULL-terminated array of our plugins.
+   * Array of our plugins.
    */
   struct Plugin **plugins;
 
+  /**
+   * Size of the 'plugins' array.
+   */
+  unsigned int num_plugins;
+
   /**
    * Our configuration.
-   */ 
+   */
   const struct GNUNET_CONFIGURATION_Handle *cfg;
 };
 
 
 /**
  * Mingle hash with the mingle_number to produce different bits.
- * 
+ *
  * @param in original hash code
  * @param mingle_number number for hash permutation
  * @param hc where to store the result.
  */
 void
-GNUNET_BLOCK_mingle_hash (const GNUNET_HashCode * in,
-                         int32_t mingle_number, 
-                         GNUNET_HashCode * hc)
+GNUNET_BLOCK_mingle_hash (const struct GNUNET_HashCode *in,
+                         uint32_t mingle_number,
+                          struct GNUNET_HashCode *hc)
 {
-  GNUNET_HashCode m;
+  struct GNUNET_HashCode m;
 
-  GNUNET_CRYPTO_hash (&mingle_number, 
-                     sizeof (int32_t), 
-                     &m);
-  GNUNET_CRYPTO_hash_xor (&m, in, hc);
+  GNUNET_CRYPTO_hash (&mingle_number,
+                      sizeof (uint32_t),
+                      &m);
+  GNUNET_CRYPTO_hash_xor (&m,
+                          in,
+                          hc);
 }
 
 
+/**
+ * Add a plugin to the list managed by the block library.
+ *
+ * @param cls the block context
+ * @param library_name name of the plugin
+ * @param lib_ret the plugin API
+ */
+static void
+add_plugin (void *cls,
+           const char *library_name,
+           void *lib_ret)
+{
+  struct GNUNET_BLOCK_Context *ctx = cls;
+  struct GNUNET_BLOCK_PluginFunctions *api = lib_ret;
+  struct Plugin *plugin;
+
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+             "Loading block plugin `%s'\n",
+              library_name);
+  plugin = GNUNET_new (struct Plugin);
+  plugin->api = api;
+  plugin->library_name = GNUNET_strdup (library_name);
+  GNUNET_array_append (ctx->plugins,
+                       ctx->num_plugins,
+                       plugin);
+}
+
+
+
 /**
  * Create a block context.  Loads the block plugins.
  *
@@ -95,50 +132,13 @@ struct GNUNET_BLOCK_Context *
 GNUNET_BLOCK_context_create (const struct GNUNET_CONFIGURATION_Handle *cfg)
 {
   struct GNUNET_BLOCK_Context *ctx;
-  struct GNUNET_BLOCK_PluginFunctions *api;
-  struct Plugin *plugin;
-  unsigned int num_plugins;
-  char *plugs;
-  char *pos;
-  char *libname;
 
-  ctx = GNUNET_malloc (sizeof (struct GNUNET_BLOCK_Context));
+  ctx = GNUNET_new (struct GNUNET_BLOCK_Context);
   ctx->cfg = cfg;
-  num_plugins = 0;
-  if (GNUNET_OK ==
-      GNUNET_CONFIGURATION_get_value_string (cfg,
-                                             "block", "PLUGINS", &plugs))
-    {
-      GNUNET_log (GNUNET_ERROR_TYPE_INFO,
-                  _("Loading block plugins `%s'\n"), plugs);
-      pos = strtok (plugs, " ");
-      while (pos != NULL)
-        {
-         GNUNET_asprintf (&libname, "libgnunet_plugin_block_%s", pos);
-         api = GNUNET_PLUGIN_load (libname, NULL);
-         if (api == NULL)
-           {
-             GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-                         _("Failed to load block plugin `%s'\n"),
-                         pos);
-             GNUNET_free (libname);
-           }
-         else
-           {
-             plugin = GNUNET_malloc (sizeof (struct Plugin));
-             plugin->api = api;
-             plugin->library_name = libname;
-             GNUNET_array_append (ctx->plugins,
-                                  num_plugins,
-                                  plugin);
-           }
-          pos = strtok (NULL, " ");
-        }
-      GNUNET_free (plugs);
-    }
-  GNUNET_array_append (ctx->plugins,
-                      num_plugins,
-                      NULL);
+  GNUNET_PLUGIN_load_all ("libgnunet_plugin_block_",
+                          NULL,
+                          &add_plugin,
+                          ctx);
   return ctx;
 }
 
@@ -154,21 +154,99 @@ GNUNET_BLOCK_context_destroy (struct GNUNET_BLOCK_Context *ctx)
   unsigned int i;
   struct Plugin *plugin;
 
-  i = 0;
-  while (NULL != (plugin = ctx->plugins[i]))
-    {
-      GNUNET_break (NULL == 
-                   GNUNET_PLUGIN_unload (plugin->library_name,
-                                         plugin->api));
-      GNUNET_free (plugin->library_name);
-      GNUNET_free (plugin);
-      i++;
-    }
+  for (i = 0; i < ctx->num_plugins; i++)
+  {
+    plugin = ctx->plugins[i];
+    GNUNET_break (NULL ==
+                  GNUNET_PLUGIN_unload (plugin->library_name,
+                                        plugin->api));
+    GNUNET_free (plugin->library_name);
+    GNUNET_free (plugin);
+  }
   GNUNET_free (ctx->plugins);
   GNUNET_free (ctx);
 }
 
 
+/**
+ * Serialize state of a block group.
+ *
+ * @param bg group to serialize
+ * @param[out] nonce set to the nonce of the @a bg
+ * @param[out] raw_data set to the serialized state
+ * @param[out] raw_data_size set to the number of bytes in @a raw_data
+ * @return #GNUNET_OK on success, #GNUNET_NO if serialization is not
+ *         supported, #GNUNET_SYSERR on error
+ */
+int
+GNUNET_BLOCK_group_serialize (struct GNUNET_BLOCK_Group *bg,
+                              uint32_t *nonce,
+                              void **raw_data,
+                              size_t *raw_data_size)
+{
+  *nonce = 0;
+  *raw_data = NULL;
+  *raw_data_size = 0;
+  if (NULL == bg)
+    return GNUNET_NO;
+  if (NULL == bg->serialize_cb)
+    return GNUNET_NO;
+  return bg->serialize_cb (bg,
+                           nonce,
+                           raw_data,
+                           raw_data_size);
+}
+
+
+/**
+ * Destroy resources used by a block group.
+ *
+ * @param bg group to destroy, NULL is allowed
+ */
+void
+GNUNET_BLOCK_group_destroy (struct GNUNET_BLOCK_Group *bg)
+{
+  if (NULL == bg)
+    return;
+  bg->destroy_cb (bg);
+}
+
+
+/**
+ * Try merging two block groups.  Afterwards, @a bg1 should remain
+ * valid and contain the rules from both @a bg1 and @bg2, and
+ * @a bg2 should be destroyed (as part of this call).  The latter
+ * should happen even if merging is not supported.
+ *
+ * @param[in,out] bg1 first group to merge, is updated
+ * @param bg2 second group to merge, is destroyed
+ * @return #GNUNET_OK on success,
+ *         #GNUNET_NO if merge failed due to different nonce
+ *         #GNUNET_SYSERR if merging is not supported
+ */
+int
+GNUNET_BLOCK_group_merge (struct GNUNET_BLOCK_Group *bg1,
+                          struct GNUNET_BLOCK_Group *bg2)
+{
+  int ret;
+
+  if (NULL == bg2)
+    return GNUNET_OK;
+  if (NULL == bg1)
+  {
+    bg2->destroy_cb (bg2);
+    return GNUNET_OK;
+  }
+  if (NULL == bg1->merge_cb)
+    return GNUNET_SYSERR;
+  GNUNET_assert (bg1->merge_cb == bg1->merge_cb);
+  ret = bg1->merge_cb (bg1,
+                       bg2);
+  bg2->destroy_cb (bg2);
+  return ret;
+}
+
+
 /**
  * Find a plugin for the given type.
  *
@@ -181,61 +259,106 @@ find_plugin (struct GNUNET_BLOCK_Context *ctx,
             enum GNUNET_BLOCK_Type type)
 {
   struct Plugin *plugin;
-  unsigned int i;
   unsigned int j;
 
-  i = 0;
-  while (NULL != (plugin = ctx->plugins[i]))
+  for (unsigned i = 0; i < ctx->num_plugins; i++)
+  {
+    plugin = ctx->plugins[i];
+    j = 0;
+    while (0 != (plugin->api->types[j]))
     {
-      j = 0;
-      while (0 != (plugin->api->types[j]))
-       {
-         if (type == plugin->api->types[j])
-           return plugin->api;
-         j++;
-       }
-      i++;
+      if (type == plugin->api->types[j])
+        return plugin->api;
+      j++;
     }
+  }
   return NULL;
 }
 
 
+/**
+ * Create a new block group.
+ *
+ * @param ctx block context in which the block group is created
+ * @param type type of the block for which we are creating the group
+ * @param nonce random value used to seed the group creation
+ * @param raw_data optional serialized prior state of the group, NULL if unavailable/fresh
+ * @param raw_data_size number of bytes in @a raw_data, 0 if unavailable/fresh
+ * @return block group handle, NULL if block groups are not supported
+ *         by this @a type of block (this is not an error)
+ */
+struct GNUNET_BLOCK_Group *
+GNUNET_BLOCK_group_create (struct GNUNET_BLOCK_Context *ctx,
+                           enum GNUNET_BLOCK_Type type,
+                           uint32_t nonce,
+                           const void *raw_data,
+                           size_t raw_data_size,
+                           ...)
+{
+  struct GNUNET_BLOCK_PluginFunctions *plugin;
+  struct GNUNET_BLOCK_Group *bg;
+  va_list ap;
+
+  plugin = find_plugin (ctx,
+                        type);
+  if (NULL == plugin->create_group)
+    return NULL;
+  va_start (ap,
+            raw_data_size);
+  bg = plugin->create_group (plugin->cls,
+                             type,
+                             nonce,
+                             raw_data,
+                             raw_data_size,
+                             ap);
+  va_end (ap);
+  return bg;
+}
+
+
 /**
  * Function called to validate a reply or a request.  For
  * request evaluation, simply pass "NULL" for the reply_block.
- * Note that it is assumed that the reply has already been 
+ * Note that it is assumed that the reply has already been
  * matched to the key (and signatures checked) as it would
  * be done with the "get_key" function.
  *
  * @param ctx block contxt
  * @param type block type
+ * @param block block group to use
+ * @param eo control flags
  * @param query original query (hash)
- * @param bf pointer to bloom filter associated with query; possibly updated (!)
- * @param bf_mutator mutation value for bf
  * @param xquery extended query data (can be NULL, depending on type)
- * @param xquery_size number of bytes in xquery
+ * @param xquery_size number of bytes in @a xquery
  * @param reply_block response to validate
- * @param reply_block_size number of bytes in reply block
+ * @param reply_block_size number of bytes in @a reply_block
  * @return characterization of result
  */
 enum GNUNET_BLOCK_EvaluationResult
 GNUNET_BLOCK_evaluate (struct GNUNET_BLOCK_Context *ctx,
-                      enum GNUNET_BLOCK_Type type,
-                      const GNUNET_HashCode *query,
-                      struct GNUNET_CONTAINER_BloomFilter **bf,
-                      int32_t bf_mutator,
-                      const void *xquery,
-                      size_t xquery_size,
-                      const void *reply_block,
-                      size_t reply_block_size)
+                       enum GNUNET_BLOCK_Type type,
+                       struct GNUNET_BLOCK_Group *group,
+                       enum GNUNET_BLOCK_EvaluationOptions eo,
+                       const struct GNUNET_HashCode *query,
+                       const void *xquery,
+                       size_t xquery_size,
+                       const void *reply_block,
+                       size_t reply_block_size)
 {
-  struct GNUNET_BLOCK_PluginFunctions *plugin = find_plugin (ctx, type);
+  struct GNUNET_BLOCK_PluginFunctions *plugin = find_plugin (ctx,
+                                                             type);
 
-  if (plugin == NULL)
+  if (NULL == plugin)
     return GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED;
   return plugin->evaluate (plugin->cls,
-                          type, query, bf, bf_mutator,
-                          xquery, xquery_size, reply_block, reply_block_size);
+                           type,
+                           group,
+                           eo,
+                           query,
+                           xquery,
+                           xquery_size,
+                           reply_block,
+                           reply_block_size);
 }
 
 
@@ -245,24 +368,55 @@ GNUNET_BLOCK_evaluate (struct GNUNET_BLOCK_Context *ctx,
  * @param ctx block context
  * @param type block type
  * @param block block to get the key for
- * @param block_size number of bytes in block
+ * @param block_size number of bytes in @a block
  * @param key set to the key (query) for the given block
- * @return GNUNET_OK on success, GNUNET_SYSERR if type not supported
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR if type not supported
  *         (or if extracting a key from a block of this type does not work)
  */
 int
 GNUNET_BLOCK_get_key (struct GNUNET_BLOCK_Context *ctx,
-                     enum GNUNET_BLOCK_Type type,
-                     const void *block,
-                     size_t block_size,
-                     GNUNET_HashCode *key)
+                      enum GNUNET_BLOCK_Type type,
+                      const void *block,
+                      size_t block_size,
+                      struct GNUNET_HashCode *key)
 {
-  struct GNUNET_BLOCK_PluginFunctions *plugin = find_plugin (ctx, type);
+  struct GNUNET_BLOCK_PluginFunctions *plugin = find_plugin (ctx,
+                                                             type);
 
   if (plugin == NULL)
     return GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED;
   return plugin->get_key (plugin->cls,
-                         type, block, block_size, key);
+                          type,
+                          block,
+                          block_size,
+                          key);
+}
+
+
+/**
+ * Update block group to filter out the given results.  Note that the
+ * use of a hash for seen results implies that the caller magically
+ * knows how the specific block engine hashes for filtering
+ * duplicates, so this API may not always apply.
+ *
+ * @param bf_mutator mutation value to use
+ * @param seen_results results already seen
+ * @param seen_results_count number of entries in @a seen_results
+ * @return #GNUNET_SYSERR if not supported, #GNUNET_OK on success
+ */
+int
+GNUNET_BLOCK_group_set_seen (struct GNUNET_BLOCK_Group *bg,
+                             const struct GNUNET_HashCode *seen_results,
+                             unsigned int seen_results_count)
+{
+  if (NULL == bg)
+    return GNUNET_OK;
+  if (NULL == bg->mark_seen_cb)
+    return GNUNET_SYSERR;
+  bg->mark_seen_cb (bg,
+                    seen_results,
+                    seen_results_count);
+  return GNUNET_OK;
 }