1 /*
2  * Copyright 2018 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 #include <iomanip>
18 #include <sstream>
19 #include <type_traits>
20 
21 #include "avrcp_packet.h"
22 
23 namespace bluetooth {
24 namespace avrcp {
25 
MakeBuilder(CType type,uint8_t subunit_type,uint8_t subunit_id,Opcode opcode,std::unique_ptr<::bluetooth::PacketBuilder> payload)26 std::unique_ptr<PacketBuilder> PacketBuilder::MakeBuilder(
27     CType type, uint8_t subunit_type, uint8_t subunit_id, Opcode opcode,
28     std::unique_ptr<::bluetooth::PacketBuilder> payload) {
29   std::unique_ptr<PacketBuilder> builder = std::unique_ptr<PacketBuilder>(
30       new PacketBuilder(type, subunit_type, subunit_id, opcode));
31 
32   builder->payload_ = std::move(payload);
33 
34   return builder;
35 }
36 
size() const37 size_t PacketBuilder::size() const {
38   // The size of the header for an Packet is 3
39   return payload_->size() + Packet::kMinSize();
40 }
41 
Serialize(const std::shared_ptr<::bluetooth::Packet> & pkt)42 bool PacketBuilder::Serialize(const std::shared_ptr<::bluetooth::Packet>& pkt) {
43   ReserveSpace(pkt, size());
44 
45   // Push the header for the packet
46   PushHeader(pkt);
47 
48   // Push the payload for the packet
49   return payload_->Serialize(pkt);
50 }
51 
PushHeader(const std::shared_ptr<::bluetooth::Packet> & pkt)52 void PacketBuilder::PushHeader(
53     const std::shared_ptr<::bluetooth::Packet>& pkt) {
54   AddPayloadOctets1(pkt, static_cast<uint8_t>(c_type_));
55   AddPayloadOctets1(pkt, (subunit_type_ << 3) | subunit_id_);
56   AddPayloadOctets1(pkt, static_cast<uint8_t>(opcode_));
57 }
58 
PushCompanyId(const std::shared_ptr<::bluetooth::Packet> & pkt,uint32_t company_id)59 bool PacketBuilder::PushCompanyId(
60     const std::shared_ptr<::bluetooth::Packet>& pkt, uint32_t company_id) {
61   company_id = base::ByteSwap(company_id);
62   for (int i = 0; i < 3; i++) {
63     company_id >>= 8;
64     AddPayloadOctets1(pkt, company_id & 0xFF);
65   }
66 
67   return true;
68 }
69 
Parse(std::shared_ptr<::bluetooth::Packet> pkt)70 std::shared_ptr<Packet> Packet::Parse(
71     std::shared_ptr<::bluetooth::Packet> pkt) {
72   return std::shared_ptr<Packet>(new Packet(pkt));
73 }
74 
GetCType() const75 CType Packet::GetCType() const {
76   auto value = *begin() & 0x0F;
77   return static_cast<CType>(value);
78 }
79 
GetSubunitType() const80 uint8_t Packet::GetSubunitType() const {
81   return *(begin() + static_cast<size_t>(1)) >> 3;
82 }
83 
GetSubunitId() const84 uint8_t Packet::GetSubunitId() const {
85   return *(begin() + static_cast<size_t>(1)) & 0b00000111;
86 }
87 
GetOpcode() const88 Opcode Packet::GetOpcode() const {
89   auto value = *(begin() + static_cast<size_t>(2));
90   return static_cast<Opcode>(value);
91 }
92 
IsValid() const93 bool Packet::IsValid() const { return size() >= kMinSize(); }
94 
ToString() const95 std::string Packet::ToString() const {
96   std::stringstream ss;
97   ss << "avrcp::Packet: " << std::endl;
98   ss << "  └ cType = " << GetCType() << std::endl;
99   ss << "  └ Subunit Type = " << loghex(GetSubunitType()) << std::endl;
100   ss << "  └ Subunit ID = " << loghex(GetSubunitId()) << std::endl;
101   ss << "  └ OpCode = " << GetOpcode() << std::endl;
102   ss << "  └ Payload =";
103   for (auto it = begin() + static_cast<size_t>(3); it != end(); it++) {
104     ss << " " << loghex(*it);
105   }
106   ss << std::endl;
107 
108   return ss.str();
109 }
110 
GetPayloadIndecies() const111 std::pair<size_t, size_t> Packet::GetPayloadIndecies() const {
112   return std::pair<size_t, size_t>(packet_start_index_ + 3, packet_end_index_);
113 }
114 
115 }  // namespace avrcp
116 }  // namespace bluetooth