include/babeltrace/babeltrace.h

   1 #ifndef _BABELTRACE_H
   2 #define _BABELTRACE_H
   3
   4 /*
   5  * BabelTrace API
   6  *
   7  * Copyright 2010-2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   8  *
   9  * Permission is hereby granted, free of charge, to any person obtaining a copy
  10  * of this software and associated documentation files (the "Software"), to deal
  11  * in the Software without restriction, including without limitation the rights
  12  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  13  * copies of the Software, and to permit persons to whom the Software is
  14  * furnished to do so, subject to the following conditions:
  15  *
  16  * The above copyright notice and this permission notice shall be included in
  17  * all copies or substantial portions of the Software.
  18  */
  19
  20 #include <babeltrace/context.h>
  21 #include <babeltrace/format.h>
  22 #include <babeltrace/iterator.h>
  23 #include <babeltrace/trace-collection.h>
  24 #include <babeltrace/trace-handle.h>
  25 #include <babeltrace/ctf/events.h>
  26
  27 /* Forward declarations */
  28 struct bt_iter;
  29 struct ctf_stream_event;
  30 struct ctf_stream;
  31 struct bt_dependencies;
  32
  33 enum bt_cb_ret {
  34         BT_CB_OK                = 0,
  35         BT_CB_OK_STOP           = 1,
  36         BT_CB_ERROR_STOP        = 2,
  37         BT_CB_ERROR_CONTINUE    = 3,
  38 };
  39
  40 /*
  41  * Receives a variable number of strings as parameter, ended with NULL.
  42  */
  43 struct bt_dependencies *babeltrace_dependencies_create(const char *first, ...);
  44
  45 /*
  46  * struct bt_dependencies must be destroyed explicitly if not passed as
  47  * parameter to a bt_iter_add_callback().
  48  */
  49 void babeltrace_dependencies_destroy(struct bt_dependencies *dep);
  50
  51 /*
  52  * bt_iter_add_callback: Add a callback to iterator.
  53  *
  54  * @iter: trace collection iterator (input)
  55  * @event: event to target. 0 for all events.
  56  * @private_data: private data pointer to pass to the callback
  57  * @flags: specific flags controlling the behavior of this callback
  58  *         (or'd).
  59  *
  60  * @callback: function pointer to call
  61  * @depends: struct bt_dependency detailing the required computation results.
  62  *           Ends with 0.
  63  * @weak_depends: struct bt_dependency detailing the optional computation
  64  *                results that can be optionally consumed by this
  65  *                callback.
  66  * @provides: struct bt_dependency detailing the computation results
  67  *            provided by this callback.
  68  *            Ends with 0.
  69  *
  70  * "depends", "weak_depends" and "provides" memory is handled by the
  71  * babeltrace library after this call succeeds or fails. These objects
  72  * can still be used by the caller until the babeltrace iterator is
  73  * destroyed, but they belong to the babeltrace library.
  74  *
  75  * (note to implementor: we need to keep a gptrarray of struct
  76  * bt_dependencies to "garbage collect" in struct bt_iter, and
  77  * dependencies need to have a refcount to handle the case where they
  78  * would be passed to more than one iterator. Upon iterator detroy, we
  79  * iterate on all the gc ptrarray and decrement the refcounts, freeing
  80  * if we reach 0.)
  81  * (note to implementor: we calculate the dependency graph when
  82  * bt_iter_read_event() is executed after a
  83  * bt_iter_add_callback(). Beware that it is valid to create/add
  84  * callbacks/read/add more callbacks/read some more.)
  85  */
  86 int bt_iter_add_callback(struct bt_iter *iter,
  87                 bt_intern_str event, void *private_data, int flags,
  88                 enum bt_cb_ret (*callback)(struct bt_ctf_event *ctf_data,
  89                                            void *caller_data),
  90                 struct bt_dependencies *depends,
  91                 struct bt_dependencies *weak_depends,
  92                 struct bt_dependencies *provides);
  93
  94 /*
  95  * For flags parameter above.
  96  */
  97 enum {
  98         BT_FLAGS_FREE_PRIVATE_DATA      = (1 << 0),
  99 };
 100
 101 #endif /* _BABELTRACE_H */