the hook callback shall return 0 in case of success.

the number of returned samples is now updated in the passed hook_info::count

include/villas/hook.h

@@ -97,6 +97,7 @@ struct hook_type {
 	enum hook_when when;	/**< The type of the hook as a bitfield */
 	hook_cb_t cb;		/**< The hook callback function as a function pointer. */
 	int priority;		/**< Default priority of this hook type. */
+	size_t size;		/**< Size of allocation for struct hook::_vd */
 };
 
 /** Descriptor for user defined hooks. See hooks[]. */
@@ -133,17 +134,6 @@ int hook_destroy(struct hook *h);
 /** Compare two hook functions with their priority. Used by list_sort() */
 int hook_cmp_priority(const void *a, const void *b);
 
-/** Allocate & deallocate private memory per hook.
- *
- * Hooks which use this function must be flagged with HOOL_STORAGE.
- *
- * @param h A pointer to the hook structure.
- * @param when Which event cause the hook to be executed?
- * @param len The size of hook prvate memory allocation.
- * @return A pointer to the allocated memory region or NULL after it was released.
- */
-void * hook_storage(struct hook *h, int when, size_t len, ctor_cb_t ctor, dtor_cb_t dtor);
-
 /** Parses an object of hooks
  *
  * Example:

lib/hooks/convert.c

@@ -48,7 +48,7 @@ static int hook_convert(struct hook *h, int when, struct hook_info *j)
 				}
 			}
 			
-			return j->count;
+			break;
 	}
 
 	return 0;

lib/hooks/fix_ts.c

@@ -34,7 +34,7 @@ int hook_fix_ts(struct hook *h, int when, struct hook_info *j)
 			j->samples[i]->ts.origin = now;
 	}
 
-	return j->count;
+	return 0;
 }
 
 static struct plugin p = {

lib/hooks/print.c

@@ -52,7 +52,7 @@ static int hook_print(struct hook *h, int when, struct hook_info *j)
 			break;
 	}
 
-	return j->count;
+	return 0;
 }
 
 static struct plugin p = {

lib/hooks/restart.c

@@ -33,7 +33,7 @@ static int hook_restart(struct hook *h, int when, struct hook_info *j)
 		h->prev = h->last;
 	}
 
-	return j->count;
+	return 0;
 }
 
 static struct plugin p = {

lib/hooks/shift.c

@@ -95,7 +95,7 @@ static int hook_shift(struct hook *h, int when, struct hook_info *j)
 				}
 			}
 
-			return j->count;
+			break;
 	}
 
 	return 0;

lib/hooks/skip_first.c

@@ -111,8 +111,8 @@ static int hook_skip_first(struct hook *h, int when, struct hook_info *j)
 				 * only the first 'ok' samples in 'smps[]' are accepted and further processed.
 				 */
 			}
-
-			return ok;
+			
+			j->count = ok;
 	}
 
 	return 0;

lib/hooks/stats.c

@@ -102,7 +102,7 @@ static int hook_stats(struct hook *h, int when, struct hook_info *j)
 			break;
 	}
 	
-	return j->count;
+	return 0;
 }
 
 struct stats_send {

lib/hooks/ts.c

@@ -19,7 +19,7 @@ static int hook_ts(struct hook *h, int when, struct hook_info *j)
 	for (int i = 0; i < j->count; i++)
 		j->samples[i]->ts.origin = j->samples[i]->ts.received;
 
-	return j->count;
+	return 0;
 }
 
 static struct plugin p = {