summaryrefslogtreecommitdiffstats
path: root/cpukit/libmisc/capture/capture_buffer.h
blob: cd26544ee12003f32d973133034d9e32e9cca5a3 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
/* SPDX-License-Identifier: BSD-2-Clause */

/**
 * @file
 *
 * @brief Capture buffer
 *
 * This is a set of functions to control a variable length capture
 * record buffer.
 */

/*
 * COPYRIGHT (c) 2014.
 * On-Line Applications Research Corporation (OAR).
 *
 * Copyright 2016 Chris Johns <chrisj@rtems.org>.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef __CAPTURE_BUFFER_H_
#define __CAPTURE_BUFFER_H_

#include <stdlib.h>

/**@{*/
#ifdef __cplusplus
extern "C" {
#endif

/**
 * Capture buffer. There is one per CPU.
 */
typedef struct rtems_capture_buffer {
  uint8_t* buffer;       /**< The per cpu buffer. */
  size_t   size;         /**< The size of the buffer in bytes. */
  size_t   count;        /**< The number of used bytes in the buffer. */
  size_t   head;         /**< First record. */
  size_t   tail;         /**< Head == Tail for empty. */
  size_t   end;          /**< Buffer current end, it may move in. */
  size_t   max_rec;      /**< The largest record in the buffer. */
} rtems_capture_buffer;

static inline void
rtems_capture_buffer_flush (rtems_capture_buffer* buffer)
{
  buffer->end = buffer->size;
  buffer->head = buffer->tail =  0;
  buffer->count = 0;
  buffer->max_rec = 0;
}

static inline void
rtems_capture_buffer_create (rtems_capture_buffer* buffer, size_t size)
{
  buffer->buffer = malloc(size);
  buffer->size = size;
  rtems_capture_buffer_flush (buffer);
}

static inline void
rtems_capture_buffer_destroy (rtems_capture_buffer*  buffer)
{
  rtems_capture_buffer_flush (buffer);
  free (buffer->buffer);
  buffer->buffer = NULL;
}

static inline bool
rtems_capture_buffer_is_empty (rtems_capture_buffer* buffer)
{
   return buffer->count == 0;
}

static inline bool
rtems_capture_buffer_is_full (rtems_capture_buffer* buffer)
{
   return buffer->count == buffer->size;
}

static inline bool
rtems_capture_buffer_has_wrapped (rtems_capture_buffer* buffer)
{
  if (buffer->tail > buffer->head)
    return true;

  return false;
}

static inline void*
rtems_capture_buffer_peek (rtems_capture_buffer* buffer, size_t* size)
{
  if (rtems_capture_buffer_is_empty (buffer))
  {
    *size = 0;
    return NULL;
  }

  if (buffer->tail > buffer->head)
    *size = buffer->end - buffer->tail;
  else
    *size = buffer->head - buffer->tail;

  return &buffer->buffer[buffer->tail];
}

void* rtems_capture_buffer_allocate (rtems_capture_buffer* buffer, size_t size);

void* rtems_capture_buffer_free (rtems_capture_buffer* buffer, size_t size);

#ifdef __cplusplus
}
#endif

#endif