Add bt_notification_heap interface

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

diff --git a/plugins/ctf/common/notif-iter/notif-heap.h b/plugins/ctf/common/notif-iter/notif-heap.h
new file mode 100644 (file)
index 0000000..1c877e9
--- /dev/null
+++ b/plugins/ctf/common/notif-iter/notif-heap.h
@@ -0,0 +1,91 @@
+#ifndef BT_NOTIFICATION_PRIO_HEAP_H
+#define BT_NOTIFICATION_PRIO_HEAP_H
+
+/*
+ * Babeltrace - Priority Heap
+ *
+ * Copyright (c) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * Copyright (c) 2016 Jérémie Galarneau <jeremie.galarneau@efficios.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <stddef.h>
+#include <stdbool.h>
+#include <babeltrace/plugin/notification/notification.h>
+#include <babeltrace/babeltrace-internal.h>
+
+/**
+ * bt_notification_time_compare - Compare two notifications' timestamps
+ *
+ * Compare two notifications in the time domain. Return true if 'a' happened
+ * prior to 'b'. In the case where both notifications are deemed to have
+ * happened at the same time, an implementation-defined critarion shall be
+ * used to order the notifications. This criterion shall ensure a consistent
+ * ordering over multiple runs.
+ */
+typedef bool (bt_notification_time_compare_func)(
+               struct bt_notification *a, struct bt_notification *b);
+
+/**
+ * bt_notification_heap_create - create a new bt_notification heap.
+ *
+ * @comparator: Function to use for notification comparisons.
+ *
+ * Returns a new notification heap, NULL on error.
+ */
+extern struct bt_notification_heap *bt_notification_heap_create(
+               bt_notification_time_compare_func comparator);
+
+/**
+ * bt_notification_heap_insert - insert an element into the heap
+ *
+ * @heap: the heap to be operated on
+ * @notification: the notification to add
+ *
+ * Insert a notification into the heap.
+ *
+ * Returns 0 on success, a negative value on error.
+ */
+extern int bt_notification_heap_insert(struct bt_notification_heap *heap,
+               struct bt_notification *notification);
+
+/**
+ * bt_notification_heap_peek - return the element on top of the heap.
+ *
+ * @heap: the heap to be operated on
+ *
+ * Returns the top element of the heap, without performing any modification
+ * to the heap structure. Returns NULL if the heap is empty. The returned
+ * notification must be bt_put() by the caller.
+ */
+extern struct bt_notification *bt_notification_heap_peek(
+               struct bt_notification_heap *heap);
+
+/**
+ * bt_notification_heap_pop - remove the element sitting on top of the heap.
+ * @heap: the heap to be operated on
+ *
+ * Returns the top element of the heap. The element is removed from the
+ * heap. Returns NULL if the heap is empty. The returned notification must be
+ * bt_put() by the caller.
+ */
+extern void *bt_notification_heap_pop(struct bt_notification_heap *heap);
+
+#endif /* BT_NOTIFICATION_PRIO_HEAP_H */