7 * Copyright 2010-2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
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:
16 * The above copyright notice and this permission notice shall be included in
17 * all copies or substantial portions of the Software.
22 #include <babeltrace/format.h>
24 typedef GQuark bt_event_name
;
26 /* Forward declarations */
27 struct babeltrace_iter
;
28 struct trace_collection
;
29 struct ctf_stream_event
;
31 struct babeltrace_saved_pos
;
32 struct bt_dependencies
;
38 BT_CB_ERROR_CONTINUE
= 3,
41 struct trace_collection_pos
{
43 BT_SEEK_TIME
, /* uses u.seek_time */
44 BT_SEEK_RESTORE
, /* uses u.restore */
51 struct babeltrace_saved_pos
*restore
;
56 struct ctf_stream_event
*event
;
57 struct ctf_stream
*stream
;
61 * babeltrace_iter_create - Allocate a trace collection iterator.
63 * begin_pos and end_pos are optional parameters to specify the position
64 * at which the trace collection should be seeked upon iterator
65 * creation, and the position at which iteration will start returning
68 * By default, if begin_pos is NULL, a BT_SEEK_CUR is performed at
69 * creation. By default, if end_pos is NULL, a BT_SEEK_END (end of
70 * trace) is the EOF criterion.
72 struct babeltrace_iter
*babeltrace_iter_create(struct trace_collection
*tc
,
73 struct trace_collection_pos
*begin_pos
,
74 struct trace_collection_pos
*end_pos
);
77 * babeltrace_iter_destroy - Free a trace collection iterator.
79 void babeltrace_iter_destroy(struct babeltrace_iter
*iter
);
82 * babeltrace_iter_next: Move trace collection position to the next event.
84 * Returns 0 on success, a negative value on error
86 int babeltrace_iter_next(struct babeltrace_iter
*iter
);
89 * babeltrace_iter_save_pos - Save the current trace collection position.
91 * The position returned by this function needs to be freed by
92 * babeltrace_iter_free_pos after use.
94 struct trace_collection_pos
*
95 babeltrace_iter_save_pos(struct babeltrace_iter
*iter
);
98 * babeltrace_iter_free_pos - Free the position.
100 void babeltrace_iter_free_pos(struct trace_collection_pos
*pos
);
103 * babeltrace_iter_seek: seek iterator to given position.
105 * Return EOF if position is after the last event of the trace collection.
106 * Return other negative value for other errors.
107 * Return 0 for success.
109 int babeltrace_iter_seek(struct babeltrace_iter
*iter
,
110 const struct trace_collection_pos
*pos
);
113 * babeltrace_iter_read_event: Read the iterator's current event data.
115 * @iter: trace collection iterator (input)
116 * @stream: stream containing event at current position (output)
117 * @event: current event (output)
118 * Return 0 on success, negative error value on error.
120 int babeltrace_iter_read_event(struct babeltrace_iter
*iter
,
121 struct ctf_stream
**stream
,
122 struct ctf_stream_event
**event
);
125 * Receives a variable number of strings as parameter, ended with NULL.
127 struct bt_dependencies
*babeltrace_dependencies_create(const char *first
, ...);
130 * struct bt_dependencies must be destroyed explicitly if not passed as
131 * parameter to a babeltrace_iter_add_callback().
133 void babeltrace_dependencies_destroy(struct bt_dependencies
*dep
);
136 * babeltrace_iter_add_callback: Add a callback to iterator.
138 * @iter: trace collection iterator (input)
139 * @event: event to target. 0 for all events.
140 * @private_data: private data pointer to pass to the callback
141 * @flags: specific flags controlling the behavior of this callback
144 * @callback: function pointer to call
145 * @depends: struct bt_dependency detailing the required computation results.
147 * @weak_depends: struct bt_dependency detailing the optional computation
148 * results that can be optionally consumed by this
150 * @provides: struct bt_dependency detailing the computation results
151 * provided by this callback.
154 * "depends", "weak_depends" and "provides" memory is handled by the
155 * babeltrace library after this call succeeds or fails. These objects
156 * can still be used by the caller until the babeltrace iterator is
157 * destroyed, but they belong to the babeltrace library.
159 * (note to implementor: we need to keep a gptrarray of struct
160 * bt_dependencies to "garbage collect" in struct babeltrace_iter, and
161 * dependencies need to have a refcount to handle the case where they
162 * would be passed to more than one iterator. Upon iterator detroy, we
163 * iterate on all the gc ptrarray and decrement the refcounts, freeing
165 * (note to implementor: we calculate the dependency graph when
166 * babeltrace_iter_read_event() is executed after a
167 * babeltrace_iter_add_callback(). Beware that it is valid to create/add
168 * callbacks/read/add more callbacks/read some more.)
170 int babeltrace_iter_add_callback(struct babeltrace_iter
*iter
,
171 bt_event_name event
, void *private_data
, int flags
,
172 enum bt_cb_ret (*callback
)(struct bt_ctf_data
*ctf_data
,
174 struct bt_dependencies
*depends
,
175 struct bt_dependencies
*weak_depends
,
176 struct bt_dependencies
*provides
);
179 * For flags parameter above.
182 BT_FLAGS_FREE_PRIVATE_DATA
= (1 << 0),
185 #endif /* _BABELTRACE_H */