xref: /freebsd/contrib/processor-trace/libipt/internal/include/pt_section_file.h (revision f81cdf24ba5436367377f7c8e8f51f6df2a75ca7)
1 /*
2  * Copyright (c) 2013-2019, 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_SECTION_FILE_H
30 #define PT_SECTION_FILE_H
31 
32 #include <stdio.h>
33 #include <stdint.h>
34 
35 #if defined(FEATURE_THREADS)
36 #  include <threads.h>
37 #endif /* defined(FEATURE_THREADS) */
38 
39 struct pt_section;
40 
41 
42 /* File-based section mapping information. */
43 struct pt_sec_file_mapping {
44 	/* The FILE pointer. */
45 	FILE *file;
46 
47 	/* The begin and end of the section as offset into @file. */
48 	long begin, end;
49 
50 #if defined(FEATURE_THREADS)
51 	/* A lock protecting read access to this file.
52 	 *
53 	 * Since we need to first set the file position indication before
54 	 * we can read, there's a race on the file position.
55 	 */
56 	mtx_t lock;
57 #endif /* defined(FEATURE_THREADS) */
58 };
59 
60 
61 /* Map a section based on file operations.
62  *
63  * The caller has already opened the file for reading.
64  *
65  * On success, sets @section's mapping, unmap, and read pointers.
66  *
67  * Returns zero on success, a negative error code otherwise.
68  * Returns -pte_internal if @section or @file are NULL.
69  * Returns -pte_invalid if @section can't be mapped.
70  */
71 extern int pt_sec_file_map(struct pt_section *section, FILE *file);
72 
73 /* Unmap a section based on file operations.
74  *
75  * On success, clears @section's mapping, unmap, and read pointers.
76  *
77  * Returns zero on success, a negative error code otherwise.
78  * Returns -pte_internal if @section is NULL.
79  * Returns -pte_internal if @section has not been mapped.
80  */
81 extern int pt_sec_file_unmap(struct pt_section *section);
82 
83 /* Read memory from a file based section.
84  *
85  * Reads at most @size bytes from @section at @offset into @buffer.
86  *
87  * Returns the number of bytes read on success, a negative error code otherwise.
88  * Returns -pte_invalid if @section or @buffer are NULL.
89  * Returns -pte_nomap if @offset is beyond the end of the section.
90  */
91 extern int pt_sec_file_read(const struct pt_section *section, uint8_t *buffer,
92 			    uint16_t size, uint64_t offset);
93 
94 /* Compute the memory size of a section based on file operations.
95  *
96  * On success, provides the amount of memory used for mapping @section in bytes
97  * in @size.
98  *
99  * Returns zero on success, a negative error code otherwise.
100  * Returns -pte_internal if @section or @size is NULL.
101  * Returns -pte_internal if @section has not been mapped.
102  */
103 extern int pt_sec_file_memsize(const struct pt_section *section,
104 			       uint64_t *size);
105 
106 #endif /* PT_SECTION_FILE_H */
107