1 #ifndef CTF_NOTIF_ITER_H
2 #define CTF_NOTIF_ITER_H
5 * Babeltrace - CTF notification iterator
7 * Copyright (c) 2015-2016 EfficiOS Inc. and Linux Foundation
8 * Copyright (c) 2015-2016 Philippe Proulx <pproulx@efficios.com>
10 * Permission is hereby granted, free of charge, to any person obtaining a copy
11 * of this software and associated documentation files (the "Software"), to deal
12 * in the Software without restriction, including without limitation the rights
13 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
14 * copies of the Software, and to permit persons to whom the Software is
15 * furnished to do so, subject to the following conditions:
17 * The above copyright notice and this permission notice shall be included in
18 * all copies or substantial portions of the Software.
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
23 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
24 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
25 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
32 #include <babeltrace/ctf-ir/trace.h>
33 #include <babeltrace/ctf-ir/fields.h>
34 #include <babeltrace/ctf-ir/event.h>
35 #include <babeltrace/graph/clock-class-priority-map.h>
36 #include <babeltrace/babeltrace-internal.h>
39 * @file ctf-notif-iter.h
41 * CTF notification iterator
43 * This is a common internal API used by CTF source plugins. It allows
44 * one to get notifications from a user-provided medium.
48 * Medium operations status codes.
50 enum bt_ctf_notif_iter_medium_status
{
54 * The medium function called by the notification iterator
55 * function reached the end of the file.
57 BT_CTF_NOTIF_ITER_MEDIUM_STATUS_EOF
= 1,
60 * There is no data available right now, try again later.
62 BT_CTF_NOTIF_ITER_MEDIUM_STATUS_AGAIN
= 11,
64 /** Invalid argument. */
65 BT_CTF_NOTIF_ITER_MEDIUM_STATUS_INVAL
= -2,
68 BT_CTF_NOTIF_ITER_MEDIUM_STATUS_ERROR
= -1,
70 /** Everything okay. */
71 BT_CTF_NOTIF_ITER_MEDIUM_STATUS_OK
= 0,
75 * CTF notification iterator API status code.
77 enum bt_ctf_notif_iter_status
{
81 * The medium function called by the notification iterator
82 * function reached the end of the file.
84 BT_CTF_NOTIF_ITER_STATUS_EOF
= BT_CTF_NOTIF_ITER_MEDIUM_STATUS_EOF
,
87 * There is no data available right now, try again later.
89 * Some condition resulted in the
90 * bt_ctf_notif_iter_medium_ops::request_bytes() user function not
91 * having access to any data now. You should retry calling the
92 * last called notification iterator function once the situation
95 BT_CTF_NOTIF_ITER_STATUS_AGAIN
= BT_CTF_NOTIF_ITER_MEDIUM_STATUS_AGAIN
,
97 /** Invalid argument. */
98 BT_CTF_NOTIF_ITER_STATUS_INVAL
= BT_CTF_NOTIF_ITER_MEDIUM_STATUS_INVAL
,
100 /** General error. */
101 BT_CTF_NOTIF_ITER_STATUS_ERROR
= BT_CTF_NOTIF_ITER_MEDIUM_STATUS_ERROR
,
103 /** Everything okay. */
104 BT_CTF_NOTIF_ITER_STATUS_OK
= 0,
110 * Those user functions are called by the notification iterator
111 * functions to request medium actions.
113 struct bt_ctf_notif_iter_medium_ops
{
115 * Returns the next byte buffer to be used by the binary file
116 * reader to deserialize binary data.
118 * This function \em must be defined.
120 * The purpose of this function is to return a buffer of bytes
121 * to the notification iterator, of a maximum of \p request_sz
122 * bytes. If this function cannot return a buffer of at least
123 * \p request_sz bytes, it may return a smaller buffer. In
124 * either cases, \p buffer_sz must be set to the returned buffer
127 * The returned buffer's ownership remains the medium, in that
128 * it won't be freed by the notification iterator functions. The
129 * returned buffer won't be modified by the notification
130 * iterator functions either.
132 * When this function is called for the first time for a given
133 * file, the offset within the file is considered to be 0. The
134 * next times this function is called, the returned buffer's
135 * byte offset within the complete file must be the previous
136 * offset plus the last returned value of \p buffer_sz by this
139 * This function must return one of the following statuses:
141 * - <b>#BT_CTF_NOTIF_ITER_MEDIUM_STATUS_OK</b>: Everything
142 * is okay, i.e. \p buffer_sz is set to a positive value
143 * reflecting the number of available bytes in the buffer
144 * starting at the address written in \p buffer_addr.
145 * - <b>#BT_CTF_NOTIF_ITER_MEDIUM_STATUS_AGAIN</b>: No data is
146 * available right now. In this case, the notification
147 * iterator function called by the user returns
148 * #BT_CTF_NOTIF_ITER_STATUS_AGAIN, and it is the user's
149 * responsibility to make sure enough data becomes available
150 * before calling the \em same notification iterator
151 * function again to continue the decoding process.
152 * - <b>#BT_CTF_NOTIF_ITER_MEDIUM_STATUS_EOF</b>: The end of
153 * the file was reached, and no more data will ever be
154 * available for this file. In this case, the notification
155 * iterator function called by the user returns
156 * #BT_CTF_NOTIF_ITER_STATUS_EOF. This must \em not be
157 * returned when returning at least one byte of data to the
158 * caller, i.e. this must be returned when there's
159 * absolutely nothing left; should the request size be
160 * larger than what's left in the file, this function must
161 * return what's left, setting \p buffer_sz to the number of
162 * remaining bytes, and return
163 * #BT_CTF_NOTIF_ITER_MEDIUM_STATUS_EOF on the \em following
165 * - <b>#BT_CTF_NOTIF_ITER_MEDIUM_STATUS_ERROR</b>: A fatal
166 * error occured during this operation. In this case, the
167 * notification iterator function called by the user returns
168 * #BT_CTF_NOTIF_ITER_STATUS_ERROR.
170 * If #BT_CTF_NOTIF_ITER_MEDIUM_STATUS_OK is not returned, the
171 * values of \p buffer_sz and \p buffer_addr are \em ignored by
174 * @param request_sz Requested buffer size (bytes)
175 * @param buffer_addr Returned buffer address
176 * @param buffer_sz Returned buffer's size (bytes)
177 * @param data User data
178 * @returns Status code (see description above)
180 enum bt_ctf_notif_iter_medium_status (* request_bytes
)(
181 size_t request_sz
, uint8_t **buffer_addr
,
182 size_t *buffer_sz
, void *data
);
185 * Returns a stream instance (weak reference) for the given
188 * This is called after a packet header is read, and the
189 * corresponding stream class is found by the notification
192 * @param stream_class Stream class of the stream to get
193 * @param stream_id Stream (instance) ID of the stream
194 * to get (-1ULL if not available)
195 * @param data User data
196 * @returns Stream instance (weak reference) or
199 struct bt_ctf_stream
* (* get_stream
)(
200 struct bt_ctf_stream_class
*stream_class
,
201 uint64_t stream_id
, void *data
);
204 /** CTF notification iterator. */
205 struct bt_ctf_notif_iter
;
207 // TODO: Replace by the real thing
208 enum bt_ctf_notif_iter_notif_type
{
209 BT_CTF_NOTIF_ITER_NOTIF_NEW_PACKET
,
210 BT_CTF_NOTIF_ITER_NOTIF_END_OF_PACKET
,
211 BT_CTF_NOTIF_ITER_NOTIF_EVENT
,
214 struct bt_ctf_notif_iter_notif
{
215 enum bt_ctf_notif_iter_notif_type type
;
218 struct bt_ctf_notif_iter_notif_new_packet
{
219 struct bt_ctf_notif_iter_notif base
;
220 struct bt_ctf_packet
*packet
;
223 struct bt_ctf_notif_iter_notif_end_of_packet
{
224 struct bt_ctf_notif_iter_notif base
;
225 struct bt_ctf_packet
*packet
;
228 struct bt_ctf_notif_iter_notif_event
{
229 struct bt_ctf_notif_iter_notif base
;
230 struct bt_ctf_event
*event
;
234 * Creates a CTF notification iterator.
236 * Upon successful completion, the reference count of \p trace is
239 * @param trace Trace to read
240 * @param max_request_sz Maximum buffer size, in bytes, to
242 * bt_ctf_notif_iter_medium_ops::request_bytes()
244 * @param medops Medium operations
245 * @param medops_data User data (passed to medium operations)
246 * @returns New CTF notification iterator on
247 * success, or \c NULL on error
250 struct bt_ctf_notif_iter
*bt_ctf_notif_iter_create(struct bt_ctf_trace
*trace
,
251 size_t max_request_sz
, struct bt_ctf_notif_iter_medium_ops medops
,
255 * Destroys a CTF notification iterator, freeing all internal resources.
257 * The registered trace's reference count is decremented.
259 * @param notif_iter CTF notification iterator
262 void bt_ctf_notif_iter_destroy(struct bt_ctf_notif_iter
*notif_iter
);
265 * Returns the next notification from a CTF notification iterator.
267 * Upon successful completion, #BT_CTF_NOTIF_ITER_STATUS_OK is
268 * returned, and the next notification is written to \p notif.
269 * In this case, the caller is responsible for calling
270 * bt_notification_put() on the returned notification.
272 * If this function returns #BT_CTF_NOTIF_ITER_STATUS_AGAIN, the caller
273 * should make sure that data becomes available to its medium, and
274 * call this function again, until another status is returned.
276 * @param notif_iter CTF notification iterator
277 * @param cc_prio_map Clock class priority map to use when
278 * creating an event notification
279 * @param notification Returned notification if the function's
280 * return value is #BT_CTF_NOTIF_ITER_STATUS_OK
281 * @returns One of #bt_ctf_notif_iter_status values
284 enum bt_ctf_notif_iter_status
bt_ctf_notif_iter_get_next_notification(
285 struct bt_ctf_notif_iter
*notit
,
286 struct bt_clock_class_priority_map
*cc_prio_map
,
287 struct bt_notification
**notification
);
290 * Returns the first packet header and context fields. This function
291 * never needs to call the `get_stream()` medium operation because
292 * it does not create packet or event objects.
294 * @param notif_iter CTF notification iterator
295 * @param packet_header_field Packet header field (\c NULL if there's
296 * no packet header field)
297 * @param packet_context_field Packet context field (\c NULL if there's
298 * no packet context field)
299 * @returns One of #bt_ctf_notif_iter_status values
302 enum bt_ctf_notif_iter_status
bt_ctf_notif_iter_get_packet_header_context_fields(
303 struct bt_ctf_notif_iter
*notit
,
304 struct bt_ctf_field
**packet_header_field
,
305 struct bt_ctf_field
**packet_context_field
);
308 void bt_ctf_notif_iter_set_medops_data(struct bt_ctf_notif_iter
*notit
,
312 const char *bt_ctf_notif_iter_medium_status_string(
313 enum bt_ctf_notif_iter_medium_status status
)
316 case BT_CTF_NOTIF_ITER_MEDIUM_STATUS_EOF
:
317 return "BT_CTF_NOTIF_ITER_MEDIUM_STATUS_EOF";
318 case BT_CTF_NOTIF_ITER_MEDIUM_STATUS_AGAIN
:
319 return "BT_CTF_NOTIF_ITER_MEDIUM_STATUS_AGAIN";
320 case BT_CTF_NOTIF_ITER_MEDIUM_STATUS_INVAL
:
321 return "BT_CTF_NOTIF_ITER_MEDIUM_STATUS_INVAL";
322 case BT_CTF_NOTIF_ITER_MEDIUM_STATUS_ERROR
:
323 return "BT_CTF_NOTIF_ITER_MEDIUM_STATUS_ERROR";
324 case BT_CTF_NOTIF_ITER_MEDIUM_STATUS_OK
:
325 return "BT_CTF_NOTIF_ITER_MEDIUM_STATUS_OK";
332 const char *bt_ctf_notif_iter_status_string(
333 enum bt_ctf_notif_iter_status status
)
336 case BT_CTF_NOTIF_ITER_STATUS_EOF
:
337 return "BT_CTF_NOTIF_ITER_STATUS_EOF";
338 case BT_CTF_NOTIF_ITER_STATUS_AGAIN
:
339 return "BT_CTF_NOTIF_ITER_STATUS_AGAIN";
340 case BT_CTF_NOTIF_ITER_STATUS_INVAL
:
341 return "BT_CTF_NOTIF_ITER_STATUS_INVAL";
342 case BT_CTF_NOTIF_ITER_STATUS_ERROR
:
343 return "BT_CTF_NOTIF_ITER_STATUS_ERROR";
344 case BT_CTF_NOTIF_ITER_STATUS_OK
:
345 return "BT_CTF_NOTIF_ITER_STATUS_OK";
351 #endif /* CTF_NOTIF_ITER_H */