1 /*
2 * Copyright 2020 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #define LOG_TAG "btm"
18
19 #include <cstdint>
20 #include "stack/btm/btm_int_types.h" // tBTM_CB
21 #include "stack/include/rfcdefs.h" // PORT_MAX_RFC_PORTS
22
23 extern tBTM_CB btm_cb;
24
25 /*******************************************************************************
26 *
27 * Function BTM_AllocateSCN
28 *
29 * Description Look through the Server Channel Numbers for a free one.
30 *
31 * Returns Allocated SCN number or 0 if none.
32 *
33 ******************************************************************************/
BTM_AllocateSCN(void)34 uint8_t BTM_AllocateSCN(void) {
35 uint8_t x;
36 BTM_TRACE_DEBUG("BTM_AllocateSCN");
37
38 // stack reserves scn 1 for HFP, HSP we still do the correct way
39 for (x = 1; x < PORT_MAX_RFC_PORTS; x++) {
40 if (!btm_cb.btm_scn[x]) {
41 btm_cb.btm_scn[x] = true;
42 return (x + 1);
43 }
44 }
45
46 return (0); /* No free ports */
47 }
48
49 /*******************************************************************************
50 *
51 * Function BTM_TryAllocateSCN
52 *
53 * Description Try to allocate a fixed server channel
54 *
55 * Returns Returns true if server channel was available
56 *
57 ******************************************************************************/
58
BTM_TryAllocateSCN(uint8_t scn)59 bool BTM_TryAllocateSCN(uint8_t scn) {
60 /* Make sure we don't exceed max port range.
61 * Stack reserves scn 1 for HFP, HSP we still do the correct way.
62 */
63 if ((scn >= PORT_MAX_RFC_PORTS) || (scn == 1) || (scn == 0)) return false;
64
65 /* check if this port is available */
66 if (!btm_cb.btm_scn[scn - 1]) {
67 btm_cb.btm_scn[scn - 1] = true;
68 return true;
69 }
70
71 return (false); /* Port was busy */
72 }
73
74 /*******************************************************************************
75 *
76 * Function BTM_FreeSCN
77 *
78 * Description Free the specified SCN.
79 *
80 * Returns true or false
81 *
82 ******************************************************************************/
BTM_FreeSCN(uint8_t scn)83 bool BTM_FreeSCN(uint8_t scn) {
84 BTM_TRACE_DEBUG("BTM_FreeSCN ");
85 if (scn <= PORT_MAX_RFC_PORTS && scn > 0) {
86 btm_cb.btm_scn[scn - 1] = false;
87 return (true);
88 } else {
89 return (false); /* Illegal SCN passed in */
90 }
91 }
92