include/babeltrace/plugin/notification/iterator.h

   1 #ifndef BABELTRACE_PLUGIN_NOTIFICATION_ITERATOR_H
   2 #define BABELTRACE_PLUGIN_NOTIFICATION_ITERATOR_H
   3
   4 /*
   5  * BabelTrace - Plug-in Notification Iterator
   6  *
   7  * Copyright 2015 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   8  *
   9  * Author: Jérémie Galarneau <jeremie.galarneau@efficios.com>
  10  *
  11  * Permission is hereby granted, free of charge, to any person obtaining a copy
  12  * of this software and associated documentation files (the "Software"), to deal
  13  * in the Software without restriction, including without limitation the rights
  14  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  15  * copies of the Software, and to permit persons to whom the Software is
  16  * furnished to do so, subject to the following conditions:
  17  *
  18  * The above copyright notice and this permission notice shall be included in
  19  * all copies or substantial portions of the Software.
  20  *
  21  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  22  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  23  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  24  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  25  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  26  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  27  * SOFTWARE.
  28  */
  29
  30 #include <stdint.h>
  31
  32 #ifdef __cplusplus
  33 extern "C" {
  34 #endif
  35
  36 struct bt_notification;
  37 struct bt_notification_iterator;
  38
  39 /**
  40  * Status code. Errors are always negative.
  41  */
  42 enum bt_notification_iterator_status {
  43         /** No error, okay. */
  44         BT_NOTIFICATION_ITERATOR_STATUS_OK = 0,
  45         /** Invalid arguments. */
  46         BT_NOTIFICATION_ITERATOR_STATUS_INVAL = -1,
  47         /** General error. */
  48         BT_NOTIFICATION_ITERATOR_STATUS_ERROR = -2,
  49         /** Unsupported iterator feature. */
  50         BT_NOTIFICATION_ITERATOR_STATUS_UNSUPPORTED = -3,
  51
  52 };
  53
  54 /**
  55  * Notification iterator seek reference.
  56  */
  57 enum bt_notification_iterator_seek_type {
  58         /** Seek at a time relative to the beginning of the trace. */
  59         BT_NOTIFICATION_ITERATOR_SEEK_TYPE_BEGIN = 0,
  60
  61         /** Seek at a time relative to the current position. */
  62         BT_NOTIFICATION_ITERATOR_SEEK_TYPE_CURRENT = 1,
  63
  64         /** Seek at a time relative to the end of the trace. */
  65         BT_NOTIFICATION_ITERATOR_SEEK_TYPE_END = 1,
  66 };
  67
  68 /**
  69  * Get current notification at iterator's position.
  70  *
  71  * This functions will <b>not</b> advance the cursor's position.
  72  * The returned notification's reference count is already incremented.
  73  *
  74  * @param iterator      Iterator instance
  75  * @returns             Returns a bt_notification instance
  76  *
  77  * @see bt_put()
  78  */
  79 extern struct bt_notification *bt_notification_iterator_get_notification(
  80                 struct bt_notification_iterator *iterator);
  81
  82 /**
  83  * Advance the iterator's position forward.
  84  *
  85  * This function can be called repeatedly to iterate through the iterator's
  86  * associated trace.
  87  *
  88  * @param iterator      Iterator instance
  89  * @returns             Returns a bt_notification instance
  90  *
  91  * @see bt_notification_iterator_get_notification()
  92  */
  93 extern enum bt_notification_iterator_status
  94 bt_notification_iterator_next(struct bt_notification_iterator *iterator);
  95
  96 /**
  97  * Seek iterator to position.
  98  *
  99  * Sets the iterator's position for the trace associated with the iterator.
 100  * The new position is computed by adding \p time to the position specified
 101  * by \p whence.
 102  *
 103  * @param iterator      Iterator instance
 104  * @param whence        One of #bt_notification_iterator_seek_type values.
 105  * @returns             One of #bt_notification_iterator_status values;
 106  *                      if \iterator does not support seeking,
 107  *                      #BT_NOTIFICATION_ITERATOR_STATUS_UNSUPPORTED is
 108  *                      returned.
 109  *
 110  * @see bt_notification_iterator_get_notification()
 111  */
 112 extern enum bt_notification_iterator_status *bt_notification_iterator_seek(
 113                 struct bt_notification_iterator *iterator, int whence,
 114                 int64_t time);
 115
 116 extern struct bt_component *bt_notification_iterator_get_component(
 117                 struct bt_notification_iterator *iterator);
 118
 119 #ifdef __cplusplus
 120 }
 121 #endif
 122
 123 #endif /* BABELTRACE_PLUGIN_NOTIFICATION_ITERATOR_H */