1 //
2 // Copyright 2017 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 "h4_data_channel_packetizer.h"
18
19 #include <string.h> // for strerror, size_t
20 #include <unistd.h> // for ssize_t
21
22 #include <cerrno> // for errno, EAGAIN, ECONNRESET
23 #include <cstdint> // for uint8_t
24 #include <functional> // for function
25 #include <type_traits> // for remove_extent_t
26 #include <utility> // for move
27 #include <vector> // for vector
28
29 #include "log.h" // for LOG_ERROR, LOG_ALWAYS_FATAL
30 #include "model/hci/h4_parser.h" // for H4Parser, ClientDisconnectCa...
31 #include "model/hci/hci_protocol.h" // for PacketReadCallback, AsyncDataChannel
32 #include "net/async_data_channel.h" // for AsyncDataChannel
33
34 namespace rootcanal {
35
H4DataChannelPacketizer(std::shared_ptr<AsyncDataChannel> socket,PacketReadCallback command_cb,PacketReadCallback event_cb,PacketReadCallback acl_cb,PacketReadCallback sco_cb,PacketReadCallback iso_cb,ClientDisconnectCallback disconnect_cb)36 H4DataChannelPacketizer::H4DataChannelPacketizer(
37 std::shared_ptr<AsyncDataChannel> socket, PacketReadCallback command_cb,
38 PacketReadCallback event_cb, PacketReadCallback acl_cb,
39 PacketReadCallback sco_cb, PacketReadCallback iso_cb,
40 ClientDisconnectCallback disconnect_cb)
41 : uart_socket_(socket),
42 h4_parser_(command_cb, event_cb, acl_cb, sco_cb, iso_cb, true),
43 disconnect_cb_(std::move(disconnect_cb)) {}
44
Send(uint8_t type,const uint8_t * data,size_t length)45 size_t H4DataChannelPacketizer::Send(uint8_t type, const uint8_t* data,
46 size_t length) {
47 ssize_t ret = uart_socket_->Send(&type, sizeof(type));
48 if (ret == -1) {
49 LOG_ERROR("Error writing to UART (%s)", strerror(errno));
50 }
51 size_t to_be_written = ret;
52
53 ret = uart_socket_->Send(data, length);
54 if (ret == -1) {
55 LOG_ERROR("Error writing to UART (%s)", strerror(errno));
56 }
57 to_be_written += ret;
58
59 if (to_be_written != length + sizeof(type)) {
60 LOG_ERROR("%d / %d bytes written - something went wrong...",
61 static_cast<int>(to_be_written),
62 static_cast<int>(length + sizeof(type)));
63 }
64 return to_be_written;
65 }
66
OnDataReady(std::shared_ptr<AsyncDataChannel> socket)67 void H4DataChannelPacketizer::OnDataReady(
68 std::shared_ptr<AsyncDataChannel> socket) {
69
70 // Continue reading from the async data channel as long as bytes
71 // are available to read. Otherwise this limits the number of HCI
72 // packets parsed to one every 3 ticks.
73 for (;;) {
74 ssize_t bytes_to_read = h4_parser_.BytesRequested();
75 std::vector<uint8_t> buffer(bytes_to_read);
76
77 ssize_t bytes_read = socket->Recv(buffer.data(), bytes_to_read);
78 if (bytes_read == 0) {
79 LOG_INFO("remote disconnected!");
80 disconnected_ = true;
81 disconnect_cb_();
82 return;
83 }
84 if (bytes_read < 0) {
85 if (errno == EAGAIN) {
86 // No data, try again later.
87 return;
88 }
89 if (errno == ECONNRESET) {
90 // They probably rejected our packet
91 disconnected_ = true;
92 disconnect_cb_();
93 return;
94 }
95 LOG_ALWAYS_FATAL("Read error in %u: %s", h4_parser_.CurrentState(),
96 strerror(errno));
97 }
98 h4_parser_.Consume(buffer.data(), bytes_read);
99 }
100 }
101
102 } // namespace rootcanal
103