From: Christian Grothoff <christian@grothoff.org>
Date: Fri, 12 Mar 2010 12:36:50 +0000 (+0000)
Subject: enable stats get cancellation
X-Git-Tag: initial-import-from-subversion-38251~22497
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=61cfd3340e67672f351ab92dab7da72dca058c79;p=oweals%2Fgnunet.git

enable stats get cancellation
---

diff --git a/src/datastore/gnunet-service-datastore.c b/src/datastore/gnunet-service-datastore.c
index cededcca8..fac1ff1d0 100644
--- a/src/datastore/gnunet-service-datastore.c
+++ b/src/datastore/gnunet-service-datastore.c
@@ -1229,6 +1229,24 @@ unload_plugin (struct DatastorePlugin *plug)
 }
 
 
+/**
+ * Final task run after shutdown.  Unloads plugins and disconnects us from
+ * statistics.
+ */
+static void
+unload_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+  unload_plugin (plugin);
+  plugin = NULL;
+  if (filter != NULL)
+    {
+      GNUNET_CONTAINER_bloomfilter_free (filter);
+      filter = NULL;
+    }
+  GNUNET_ARM_stop_services (cfg, tc->sched, "statistics", NULL);
+}
+
+
 /**
  * Last task run during shutdown.  Disconnects us from
  * the transport and core.
@@ -1256,14 +1274,10 @@ cleaning_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 			       expired_kill_task);
       expired_kill_task = GNUNET_SCHEDULER_NO_TASK;
     }
-  unload_plugin (plugin);
-  plugin = NULL;
-  if (filter != NULL)
-    {
-      GNUNET_CONTAINER_bloomfilter_free (filter);
-      filter = NULL;
-    }
-  GNUNET_ARM_stop_services (cfg, tc->sched, "statistics", NULL);
+  GNUNET_SCHEDULER_add_continuation (sched,
+				     &unload_task,
+				     NULL,
+				     GNUNET_SCHEDULER_REASON_PREREQ_DONE);
 }
 
 
diff --git a/src/datastore/plugin_datastore_sqlite.c b/src/datastore/plugin_datastore_sqlite.c
index 2fc28e13e..9356b79ed 100644
--- a/src/datastore/plugin_datastore_sqlite.c
+++ b/src/datastore/plugin_datastore_sqlite.c
@@ -91,6 +91,7 @@
 #define BUSY_TIMEOUT_MS 250
 
 
+
 /**
  * Context for all functions in this plugin.
  */
@@ -125,6 +126,11 @@ struct Plugin
    * Handle to the statistics service.
    */
   struct GNUNET_STATISTICS_Handle *statistics;
+
+  /**
+   * Handle for pending get request.
+   */
+  struct GNUNET_STATISTICS_GetHandle *stat_get;
   
   /**
    * How much data are we currently storing
@@ -1559,6 +1565,15 @@ process_stat_in (void *cls,
 #endif
   return GNUNET_OK;
 }
+
+
+static void
+process_stat_done (void *cls,
+		   int success)
+{
+  struct Plugin *plugin = cls;
+  plugin->stat_get = NULL;
+}
 			 		 
 
 /**
@@ -1581,13 +1596,13 @@ libgnunet_plugin_datastore_sqlite_init (void *cls)
   plugin.statistics = GNUNET_STATISTICS_create (env->sched,
 						"sqlite",
 						env->cfg);
-  GNUNET_STATISTICS_get (plugin.statistics,
-			 "sqlite",
-			 QUOTA_STAT_NAME,
-			 GNUNET_TIME_UNIT_MINUTES,
-			 NULL,
-			 &process_stat_in,
-			 &plugin);
+  plugin.stat_get = GNUNET_STATISTICS_get (plugin.statistics,
+					   "sqlite",
+					   QUOTA_STAT_NAME,
+					   GNUNET_TIME_UNIT_MINUTES,
+					   &process_stat_done,
+					   &process_stat_in,
+					   &plugin);
   if (GNUNET_OK !=
       database_setup (env->cfg, &plugin))
     {
@@ -1626,6 +1641,11 @@ libgnunet_plugin_datastore_sqlite_done (void *cls)
   struct GNUNET_DATASTORE_PluginFunctions *api = cls;
   struct Plugin *plugin = api->cls;
 
+  if (plugin->stat_get != NULL)
+    {
+      GNUNET_STATISTICS_get_cancel (plugin->stat_get);
+      plugin->stat_get = NULL;
+    }
   fn = NULL;
   if (plugin->drop_on_shutdown)
     fn = GNUNET_strdup (plugin->fn);
diff --git a/src/include/gnunet_statistics_service.h b/src/include/gnunet_statistics_service.h
index 0fc84cfc3..5c166d43d 100644
--- a/src/include/gnunet_statistics_service.h
+++ b/src/include/gnunet_statistics_service.h
@@ -102,6 +102,11 @@ void GNUNET_STATISTICS_destroy (struct GNUNET_STATISTICS_Handle *h,
  */
 typedef void (*GNUNET_STATISTICS_Callback) (void *cls, int success);
 
+/**
+ * Handle that can be used to cancel a statistics 'get' operation.
+ */
+struct GNUNET_STATISTICS_GetHandle;
+
 /**
  * Get statistic from the peer.
  *
@@ -113,8 +118,9 @@ typedef void (*GNUNET_STATISTICS_Callback) (void *cls, int success);
  * @param cont continuation to call when done (can be NULL)
  * @param proc function to call on each value
  * @param cls closure for proc and cont
+ * @return NULL on error
  */
-void
+struct GNUNET_STATISTICS_GetHandle *
 GNUNET_STATISTICS_get (struct GNUNET_STATISTICS_Handle *handle,
                        const char *subsystem,
                        const char *name,
@@ -122,6 +128,17 @@ GNUNET_STATISTICS_get (struct GNUNET_STATISTICS_Handle *handle,
                        GNUNET_STATISTICS_Callback cont,
                        GNUNET_STATISTICS_Iterator proc, void *cls);
 
+
+/**
+ * Cancel a 'get' request.  Must be called before the 'cont' 
+ * function is called.
+ *
+ * @param gh handle of the request to cancel
+ */
+void
+GNUNET_STATISTICS_get_cancel (struct GNUNET_STATISTICS_GetHandle *gh);
+
+
 /**
  * Set statistic value for the peer.  Will always use our
  * subsystem (the argument used when "handle" was created).
diff --git a/src/statistics/gnunet-statistics.c b/src/statistics/gnunet-statistics.c
index f51452699..e996bb728 100644
--- a/src/statistics/gnunet-statistics.c
+++ b/src/statistics/gnunet-statistics.c
@@ -140,8 +140,9 @@ run (void *cls,
       ret = 1;
       return;
     }
-  GNUNET_STATISTICS_get (h,
-                         subsystem, name, GET_TIMEOUT, &cleanup, &printer, h);
+  if (NULL == GNUNET_STATISTICS_get (h,
+				     subsystem, name, GET_TIMEOUT, &cleanup, &printer, h))
+    cleanup (h, GNUNET_SYSERR);
 }
 
 /**
diff --git a/src/statistics/statistics_api.c b/src/statistics/statistics_api.c
index 86950ad4c..e9ebe7fa6 100644
--- a/src/statistics/statistics_api.c
+++ b/src/statistics/statistics_api.c
@@ -25,6 +25,7 @@
  */
 #include "platform.h"
 #include "gnunet_client_lib.h"
+#include "gnunet_container_lib.h"
 #include "gnunet_protocols.h"
 #include "gnunet_server_lib.h"
 #include "gnunet_statistics_service.h"
@@ -48,13 +49,24 @@ enum ActionType
 /**
  * Linked list of things we still need to do.
  */
-struct ActionItem
+struct GNUNET_STATISTICS_GetHandle
 {
+
+  /**
+   * This is a doubly linked list.
+   */
+  struct GNUNET_STATISTICS_GetHandle *next;
+
   /**
-   * This is a linked list.
+   * This is a doubly linked list.
    */
-  struct ActionItem *next;
+  struct GNUNET_STATISTICS_GetHandle *prev;
 
+  /**
+   * Main statistics handle.
+   */
+  struct GNUNET_STATISTICS_Handle *sh;
+ 
   /**
    * What subsystem is this action about? (can be NULL)
    */
@@ -147,19 +159,19 @@ struct GNUNET_STATISTICS_Handle
    * Head of the linked list of pending actions (first action
    * to be performed).
    */
-  struct ActionItem *action_head;
+  struct GNUNET_STATISTICS_GetHandle *action_head;
 
   /**
    * Tail of the linked list of actions (for fast append).
    */
-  struct ActionItem *action_tail;
+  struct GNUNET_STATISTICS_GetHandle *action_tail;
 
   /**
    * Action we are currently busy with (action request has been
    * transmitted, we're now receiving the response from the
    * service).
    */
-  struct ActionItem *current;
+  struct GNUNET_STATISTICS_GetHandle *current;
 
   /**
    * Should this handle auto-destruct once all actions have
@@ -195,7 +207,7 @@ try_connect (struct GNUNET_STATISTICS_Handle *ret)
  * Free memory associated with the given action item.
  */
 static void
-free_action_item (struct ActionItem *ai)
+free_action_item (struct GNUNET_STATISTICS_GetHandle *ai)
 {
   GNUNET_free_non_null (ai->subsystem);
   GNUNET_free_non_null (ai->name);
@@ -203,9 +215,6 @@ free_action_item (struct ActionItem *ai)
 }
 
 
-
-
-
 /**
  * Schedule the next action to be performed.
  */
@@ -218,7 +227,7 @@ static void schedule_action (struct GNUNET_STATISTICS_Handle *h);
 static void
 finish (struct GNUNET_STATISTICS_Handle *h, int code)
 {
-  struct ActionItem *pos = h->current;
+  struct GNUNET_STATISTICS_GetHandle *pos = h->current;
   h->current = NULL;
   schedule_action (h);
   if (pos->cont != NULL)
@@ -264,17 +273,17 @@ process_message (struct GNUNET_STATISTICS_Handle *h,
 #endif
   if (GNUNET_OK !=
       h->current->proc (h->current->cls,
-                        service,
-                        name,
-                        GNUNET_ntohll (smsg->value),
-                        0 !=
-                        (ntohl (smsg->uid) & GNUNET_STATISTICS_PERSIST_BIT)))
+			service,
+			name,
+			GNUNET_ntohll (smsg->value),
+			0 !=
+			(ntohl (smsg->uid) & GNUNET_STATISTICS_PERSIST_BIT)))
     {
 #if DEBUG_STATISTICS
       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-                  "Processing of remaining statistics aborted by client.\n");
+		  "Processing of remaining statistics aborted by client.\n");
 #endif
-      h->current->aborted = GNUNET_YES;
+      h->current->aborted = GNUNET_YES;    
     }
   return GNUNET_OK;
 }
@@ -495,9 +504,9 @@ void
 GNUNET_STATISTICS_destroy (struct GNUNET_STATISTICS_Handle *h,
 			   int sync_first)
 {
-  struct ActionItem *pos;
-  struct ActionItem *next;
-  struct ActionItem *prev;
+  struct GNUNET_STATISTICS_GetHandle *pos;
+  struct GNUNET_STATISTICS_GetHandle *next;
+  struct GNUNET_STATISTICS_GetHandle *prev;
   struct GNUNET_TIME_Relative timeout;
 
   if (sync_first)
@@ -606,10 +615,9 @@ schedule_action (struct GNUNET_STATISTICS_Handle *h)
 	}
       return;
     }
-  h->action_head = h->action_head->next;
-  if (NULL == h->action_head)
-    h->action_tail = NULL;
-  h->current->next = NULL;
+  GNUNET_CONTAINER_DLL_remove (h->action_head,
+			       h->action_tail,
+			       h->current);
   timeout = GNUNET_TIME_absolute_get_remaining (h->current->timeout);
   if (NULL ==
       (h->th = GNUNET_CLIENT_notify_transmit_ready (h->client,
@@ -628,19 +636,14 @@ schedule_action (struct GNUNET_STATISTICS_Handle *h)
 
 
 static void
-insert_ai (struct GNUNET_STATISTICS_Handle *h, struct ActionItem *ai)
+insert_ai (struct GNUNET_STATISTICS_Handle *h, struct GNUNET_STATISTICS_GetHandle *ai)
 {
-  if (h->action_tail == NULL)
-    {
-      h->action_head = ai;
-      h->action_tail = ai;
-      schedule_action (h);
-    }
-  else
-    {
-      h->action_tail->next = ai;
-      h->action_tail = ai;
-    }
+  GNUNET_CONTAINER_DLL_insert_after (h->action_head,
+				     h->action_tail,
+				     h->action_tail,
+				     ai);				     
+  if (h->action_head == ai)
+    schedule_action (h);
 }
 
 
@@ -655,8 +658,9 @@ insert_ai (struct GNUNET_STATISTICS_Handle *h, struct ActionItem *ai)
  * @param cont continuation to call when done (can be NULL)
  * @param proc function to call on each value
  * @param cls closure for cont and proc
+ * @return NULL on error
  */
-void
+struct GNUNET_STATISTICS_GetHandle *
 GNUNET_STATISTICS_get (struct GNUNET_STATISTICS_Handle *handle,
                        const char *subsystem,
                        const char *name,
@@ -666,7 +670,7 @@ GNUNET_STATISTICS_get (struct GNUNET_STATISTICS_Handle *handle,
 {
   size_t slen1;
   size_t slen2;
-  struct ActionItem *ai;
+  struct GNUNET_STATISTICS_GetHandle *ai;
 
   GNUNET_assert (handle != NULL);
   GNUNET_assert (proc != NULL);
@@ -679,9 +683,7 @@ GNUNET_STATISTICS_get (struct GNUNET_STATISTICS_Handle *handle,
                   strlen (subsystem) ? subsystem : "*",
                   strlen (name) ? name : "*");
 #endif
-      if (cont != NULL)
-	cont (cls, GNUNET_SYSERR);
-      return;
+      return NULL;
     }
   if (subsystem == NULL)
     subsystem = "";
@@ -691,7 +693,8 @@ GNUNET_STATISTICS_get (struct GNUNET_STATISTICS_Handle *handle,
   slen2 = strlen (name);
   GNUNET_assert (slen1 + slen2 + sizeof (struct GNUNET_MessageHeader) <
                  GNUNET_SERVER_MAX_MESSAGE_SIZE);
-  ai = GNUNET_malloc (sizeof (struct ActionItem));
+  ai = GNUNET_malloc (sizeof (struct GNUNET_STATISTICS_GetHandle));
+  ai->sh = handle;
   ai->subsystem = GNUNET_strdup (subsystem);
   ai->name = GNUNET_strdup (name);
   ai->cont = cont;
@@ -701,6 +704,32 @@ GNUNET_STATISTICS_get (struct GNUNET_STATISTICS_Handle *handle,
   ai->type = ACTION_GET;
   ai->msize = slen1 + slen2 + sizeof (struct GNUNET_MessageHeader);
   insert_ai (handle, ai);
+  return ai;
+}
+
+
+/**
+ * Cancel a 'get' request.  Must be called before the 'cont' 
+ * function is called.
+ *
+ * @param gh handle of the request to cancel
+ */
+void
+GNUNET_STATISTICS_get_cancel (struct GNUNET_STATISTICS_GetHandle *gh)
+{
+  if (gh->sh->current == gh)
+    {
+      gh->aborted = GNUNET_YES;
+    }
+  else
+    {
+      GNUNET_CONTAINER_DLL_remove (gh->sh->action_head,
+				   gh->sh->action_tail,
+				   gh);
+      GNUNET_free (gh->name);
+      GNUNET_free (gh->subsystem);
+      GNUNET_free (gh);
+    }
 }
 
 
@@ -710,7 +739,7 @@ add_setter_action (struct GNUNET_STATISTICS_Handle *h,
                    int make_persistent,
                    uint64_t value, enum ActionType type)
 {
-  struct ActionItem *ai;
+  struct GNUNET_STATISTICS_GetHandle *ai;
   size_t slen;
   size_t nlen;
   size_t nsize;
@@ -727,7 +756,8 @@ add_setter_action (struct GNUNET_STATISTICS_Handle *h,
       GNUNET_break (0);
       return;
     }
-  ai = GNUNET_malloc (sizeof (struct ActionItem));
+  ai = GNUNET_malloc (sizeof (struct GNUNET_STATISTICS_GetHandle));
+  ai->sh = h;
   ai->subsystem = GNUNET_strdup (h->subsystem);
   ai->name = GNUNET_strdup (name);
   ai->timeout = GNUNET_TIME_relative_to_absolute (SET_TRANSMIT_TIMEOUT);
diff --git a/src/statistics/test_statistics_api.c b/src/statistics/test_statistics_api.c
index 8a4a5e911..d7eb90b4d 100644
--- a/src/statistics/test_statistics_api.c
+++ b/src/statistics/test_statistics_api.c
@@ -83,8 +83,9 @@ static void
 next (void *cls, int success)
 {
   GNUNET_assert (success == GNUNET_OK);
-  GNUNET_STATISTICS_get (h, NULL, "test-2",
-                         GNUNET_TIME_UNIT_SECONDS, &next_fin, &check_2, cls);
+  GNUNET_break (NULL !=
+		GNUNET_STATISTICS_get (h, NULL, "test-2",
+				       GNUNET_TIME_UNIT_SECONDS, &next_fin, &check_2, cls));
 }
 
 static void
@@ -100,8 +101,9 @@ run (void *cls,
   GNUNET_STATISTICS_set (h, "test-2", 2, GNUNET_NO);
   GNUNET_STATISTICS_set (h, "test-3", 2, GNUNET_NO);
   GNUNET_STATISTICS_update (h, "test-3", 1, GNUNET_YES);
-  GNUNET_STATISTICS_get (h, NULL, "test-1",
-                         GNUNET_TIME_UNIT_SECONDS, &next, &check_1, cls);
+  GNUNET_break (NULL != 
+		GNUNET_STATISTICS_get (h, NULL, "test-1",
+				       GNUNET_TIME_UNIT_SECONDS, &next, &check_1, cls));
 }
 
 static void
@@ -112,8 +114,9 @@ run_more (void *cls,
 	  const struct GNUNET_CONFIGURATION_Handle *cfg)
 {
   h = GNUNET_STATISTICS_create (sched, "test-statistics-api", cfg);
-  GNUNET_STATISTICS_get (h, NULL, "test-3",
-                         GNUNET_TIME_UNIT_SECONDS, &next_fin, &check_3, cls);
+  GNUNET_break (NULL !=
+		GNUNET_STATISTICS_get (h, NULL, "test-3",
+				       GNUNET_TIME_UNIT_SECONDS, &next_fin, &check_3, cls));
 }
 
 static int