1 /******************************************************************************
2 *
3 * Copyright 2015 Google Inc.
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at:
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 *
17 ******************************************************************************/
18
19 #include "osi/include/ringbuffer.h"
20
21 #include <bluetooth/log.h>
22 #include <stdlib.h>
23
24 #include "osi/include/allocator.h"
25
26 using namespace bluetooth;
27
28 struct ringbuffer_t {
29 size_t total;
30 size_t available;
31 uint8_t* base;
32 uint8_t* head;
33 uint8_t* tail;
34 };
35
ringbuffer_init(const size_t size)36 ringbuffer_t* ringbuffer_init(const size_t size) {
37 ringbuffer_t* p = static_cast<ringbuffer_t*>(osi_calloc(sizeof(ringbuffer_t)));
38
39 p->base = static_cast<uint8_t*>(osi_calloc(size));
40 p->head = p->tail = p->base;
41 p->total = p->available = size;
42
43 return p;
44 }
45
ringbuffer_free(ringbuffer_t * rb)46 void ringbuffer_free(ringbuffer_t* rb) {
47 if (rb != NULL) {
48 osi_free(rb->base);
49 }
50 osi_free(rb);
51 }
52
ringbuffer_available(const ringbuffer_t * rb)53 size_t ringbuffer_available(const ringbuffer_t* rb) {
54 log::assert_that(rb != nullptr, "assert failed: rb != nullptr");
55 return rb->available;
56 }
57
ringbuffer_size(const ringbuffer_t * rb)58 size_t ringbuffer_size(const ringbuffer_t* rb) {
59 log::assert_that(rb != nullptr, "assert failed: rb != nullptr");
60 return rb->total - rb->available;
61 }
62
ringbuffer_insert(ringbuffer_t * rb,const uint8_t * p,size_t length)63 size_t ringbuffer_insert(ringbuffer_t* rb, const uint8_t* p, size_t length) {
64 log::assert_that(rb != nullptr, "assert failed: rb != nullptr");
65 log::assert_that(p != nullptr, "assert failed: p != nullptr");
66
67 if (length > ringbuffer_available(rb)) {
68 length = ringbuffer_available(rb);
69 }
70
71 for (size_t i = 0; i != length; ++i) {
72 *rb->tail++ = *p++;
73 if (rb->tail >= (rb->base + rb->total)) {
74 rb->tail = rb->base;
75 }
76 }
77
78 rb->available -= length;
79 return length;
80 }
81
ringbuffer_delete(ringbuffer_t * rb,size_t length)82 size_t ringbuffer_delete(ringbuffer_t* rb, size_t length) {
83 log::assert_that(rb != nullptr, "assert failed: rb != nullptr");
84
85 if (length > ringbuffer_size(rb)) {
86 length = ringbuffer_size(rb);
87 }
88
89 rb->head += length;
90 if (rb->head >= (rb->base + rb->total)) {
91 rb->head -= rb->total;
92 }
93
94 rb->available += length;
95 return length;
96 }
97
ringbuffer_peek(const ringbuffer_t * rb,off_t offset,uint8_t * p,size_t length)98 size_t ringbuffer_peek(const ringbuffer_t* rb, off_t offset, uint8_t* p, size_t length) {
99 log::assert_that(rb != nullptr, "assert failed: rb != nullptr");
100 log::assert_that(p != nullptr, "assert failed: p != nullptr");
101 log::assert_that(offset >= 0, "assert failed: offset >= 0");
102 log::assert_that((size_t)offset <= ringbuffer_size(rb),
103 "assert failed: (size_t)offset <= ringbuffer_size(rb)");
104
105 uint8_t* b = ((rb->head - rb->base + offset) % rb->total) + rb->base;
106 const size_t bytes_to_copy =
107 (offset + length > ringbuffer_size(rb)) ? ringbuffer_size(rb) - offset : length;
108
109 for (size_t copied = 0; copied < bytes_to_copy; ++copied) {
110 *p++ = *b++;
111 if (b >= (rb->base + rb->total)) {
112 b = rb->base;
113 }
114 }
115
116 return bytes_to_copy;
117 }
118
ringbuffer_pop(ringbuffer_t * rb,uint8_t * p,size_t length)119 size_t ringbuffer_pop(ringbuffer_t* rb, uint8_t* p, size_t length) {
120 log::assert_that(rb != nullptr, "assert failed: rb != nullptr");
121 log::assert_that(p != nullptr, "assert failed: p != nullptr");
122
123 const size_t copied = ringbuffer_peek(rb, 0, p, length);
124 rb->head += copied;
125 if (rb->head >= (rb->base + rb->total)) {
126 rb->head -= rb->total;
127 }
128
129 rb->available += copied;
130 return copied;
131 }
132