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 =
38 static_cast<ringbuffer_t*>(osi_calloc(sizeof(ringbuffer_t)));
39
40 p->base = static_cast<uint8_t*>(osi_calloc(size));
41 p->head = p->tail = p->base;
42 p->total = p->available = size;
43
44 return p;
45 }
46
ringbuffer_free(ringbuffer_t * rb)47 void ringbuffer_free(ringbuffer_t* rb) {
48 if (rb != NULL) osi_free(rb->base);
49 osi_free(rb);
50 }
51
ringbuffer_available(const ringbuffer_t * rb)52 size_t ringbuffer_available(const ringbuffer_t* rb) {
53 log::assert_that(rb != nullptr, "assert failed: rb != nullptr");
54 return rb->available;
55 }
56
ringbuffer_size(const ringbuffer_t * rb)57 size_t ringbuffer_size(const ringbuffer_t* rb) {
58 log::assert_that(rb != nullptr, "assert failed: rb != nullptr");
59 return rb->total - rb->available;
60 }
61
ringbuffer_insert(ringbuffer_t * rb,const uint8_t * p,size_t length)62 size_t ringbuffer_insert(ringbuffer_t* rb, const uint8_t* p, size_t length) {
63 log::assert_that(rb != nullptr, "assert failed: rb != nullptr");
64 log::assert_that(p != nullptr, "assert failed: p != nullptr");
65
66 if (length > ringbuffer_available(rb)) length = ringbuffer_available(rb);
67
68 for (size_t i = 0; i != length; ++i) {
69 *rb->tail++ = *p++;
70 if (rb->tail >= (rb->base + rb->total)) rb->tail = rb->base;
71 }
72
73 rb->available -= length;
74 return length;
75 }
76
ringbuffer_delete(ringbuffer_t * rb,size_t length)77 size_t ringbuffer_delete(ringbuffer_t* rb, size_t length) {
78 log::assert_that(rb != nullptr, "assert failed: rb != nullptr");
79
80 if (length > ringbuffer_size(rb)) length = ringbuffer_size(rb);
81
82 rb->head += length;
83 if (rb->head >= (rb->base + rb->total)) rb->head -= rb->total;
84
85 rb->available += length;
86 return length;
87 }
88
ringbuffer_peek(const ringbuffer_t * rb,off_t offset,uint8_t * p,size_t length)89 size_t ringbuffer_peek(const ringbuffer_t* rb, off_t offset, uint8_t* p,
90 size_t length) {
91 log::assert_that(rb != nullptr, "assert failed: rb != nullptr");
92 log::assert_that(p != nullptr, "assert failed: p != nullptr");
93 log::assert_that(offset >= 0, "assert failed: offset >= 0");
94 log::assert_that((size_t)offset <= ringbuffer_size(rb),
95 "assert failed: (size_t)offset <= ringbuffer_size(rb)");
96
97 uint8_t* b = ((rb->head - rb->base + offset) % rb->total) + rb->base;
98 const size_t bytes_to_copy = (offset + length > ringbuffer_size(rb))
99 ? ringbuffer_size(rb) - offset
100 : length;
101
102 for (size_t copied = 0; copied < bytes_to_copy; ++copied) {
103 *p++ = *b++;
104 if (b >= (rb->base + rb->total)) b = rb->base;
105 }
106
107 return bytes_to_copy;
108 }
109
ringbuffer_pop(ringbuffer_t * rb,uint8_t * p,size_t length)110 size_t ringbuffer_pop(ringbuffer_t* rb, uint8_t* p, size_t length) {
111 log::assert_that(rb != nullptr, "assert failed: rb != nullptr");
112 log::assert_that(p != nullptr, "assert failed: p != nullptr");
113
114 const size_t copied = ringbuffer_peek(rb, 0, p, length);
115 rb->head += copied;
116 if (rb->head >= (rb->base + rb->total)) rb->head -= rb->total;
117
118 rb->available += copied;
119 return copied;
120 }
121