xref: /freebsd/contrib/processor-trace/libipt/internal/include/pt_sync.h (revision 8df8b2d3e51d1b816201d8a1fe8bc29fe192e562)
1 /*
2  * Copyright (c) 2014-2018, Intel Corporation
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions are met:
6  *
7  *  * Redistributions of source code must retain the above copyright notice,
8  *    this list of conditions and the following disclaimer.
9  *  * Redistributions in binary form must reproduce the above copyright notice,
10  *    this list of conditions and the following disclaimer in the documentation
11  *    and/or other materials provided with the distribution.
12  *  * Neither the name of Intel Corporation nor the names of its contributors
13  *    may be used to endorse or promote products derived from this software
14  *    without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
20  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #ifndef PT_SYNC_H
30 #define PT_SYNC_H
31 
32 #include <stdint.h>
33 
34 struct pt_config;
35 
36 
37 /* Synchronize onto the trace stream.
38  *
39  * Search for the next synchronization point in forward or backward direction
40  * starting at @pos using the trace configuration @config.
41  *
42  * On success, stores a pointer to the next synchronization point in @sync.
43  *
44  * Returns zero on success, a negative error code otherwise.
45  *
46  * Returns -pte_internal if @sync, @pos, or @config is NULL.
47  * Returns -pte_nosync if @pos lies outside of @config's buffer.
48  * Returns -pte_eos if no further synchronization point is found.
49  */
50 extern int pt_sync_forward(const uint8_t **sync, const uint8_t *pos,
51 			   const struct pt_config *config);
52 extern int pt_sync_backward(const uint8_t **sync, const uint8_t *pos,
53 			    const struct pt_config *config);
54 
55 /* Manually synchronize onto the trace stream.
56  *
57  * Validate that @pos is within the bounds of @config's trace buffer and that
58  * there is a synchronization point at @pos.
59  *
60  * On success, stores @pos in @sync.
61  *
62  * Returns zero on success, a negative error code otherwise.
63  *
64  * Returns -pte_eos if @pos is outside of @config's trace buffer.
65  * Returns -pte_internal if @sync, @pos, or @config is NULL.
66  * Returns -pte_bad_packet if there is no PSB at @pos.
67  */
68 extern int pt_sync_set(const uint8_t **sync, const uint8_t *pos,
69 		       const struct pt_config *config);
70 
71 #endif /* PT_SYNC_H */
72