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 "hci_protocol.h" 18 19 #define LOG_TAG "android.hardware.bluetooth-hci-hci_protocol" 20 #include <android-base/logging.h> 21 #include <assert.h> 22 #include <fcntl.h> 23 #include <utils/Log.h> 24 25 namespace { 26 27 const size_t preamble_size_for_type[] = { 28 0, HCI_COMMAND_PREAMBLE_SIZE, HCI_ACL_PREAMBLE_SIZE, HCI_SCO_PREAMBLE_SIZE, 29 HCI_EVENT_PREAMBLE_SIZE}; 30 const size_t packet_length_offset_for_type[] = { 31 0, HCI_LENGTH_OFFSET_CMD, HCI_LENGTH_OFFSET_ACL, HCI_LENGTH_OFFSET_SCO, 32 HCI_LENGTH_OFFSET_EVT}; 33 34 size_t HciGetPacketLengthForType(HciPacketType type, const uint8_t* preamble) { 35 size_t offset = packet_length_offset_for_type[type]; 36 if (type != HCI_PACKET_TYPE_ACL_DATA) return preamble[offset]; 37 return (((preamble[offset + 1]) << 8) | preamble[offset]); 38 } 39 40 } // namespace 41 42 namespace android { 43 namespace hardware { 44 namespace bluetooth { 45 namespace hci { 46 47 size_t HciProtocol::WriteSafely(int fd, const uint8_t* data, size_t length) { 48 size_t transmitted_length = 0; 49 while (length > 0) { 50 ssize_t ret = 51 TEMP_FAILURE_RETRY(write(fd, data + transmitted_length, length)); 52 53 if (ret == -1) { 54 if (errno == EAGAIN) continue; 55 ALOGE("%s error writing to UART (%s)", __func__, strerror(errno)); 56 break; 57 58 } else if (ret == 0) { 59 // Nothing written :( 60 ALOGE("%s zero bytes written - something went wrong...", __func__); 61 break; 62 } 63 64 transmitted_length += ret; 65 length -= ret; 66 } 67 68 return transmitted_length; 69 } 70 71 } // namespace hci 72 } // namespace bluetooth 73 } // namespace hardware 74 } // namespace android 75
