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 <cstdint> 18 #include <list> 19 #include <unordered_map> 20 #include <unordered_set> 21 #include <vector> 22 23 #include "bta/include/bta_gatt_api.h" 24 25 /* BTA GATTC implementation does not allow for multiple commands queuing. So one 26 * client making calls to BTA_GATTC_ReadCharacteristic, BTA_GATTC_ReadCharDescr, 27 * BTA_GATTC_WriteCharValue, BTA_GATTC_WriteCharDescr must wait for the callacks 28 * before scheduling next operation. 29 * 30 * Methods below can be used as replacement to BTA_GATTC_* in BTA app. They do 31 * queue the commands if another command is currently being executed. 32 * 33 * If you decide to use those methods in your app, make sure to not mix it with 34 * existing BTA_GATTC_* API. 35 */ 36 class BtaGattQueue { 37 public: 38 static void Clean(tCONN_ID conn_id); 39 static void ReadCharacteristic(tCONN_ID conn_id, uint16_t handle, GATT_READ_OP_CB cb, 40 void* cb_data); 41 static void ReadDescriptor(tCONN_ID conn_id, uint16_t handle, GATT_READ_OP_CB cb, void* cb_data); 42 static void WriteCharacteristic(tCONN_ID conn_id, uint16_t handle, std::vector<uint8_t> value, 43 tGATT_WRITE_TYPE write_type, GATT_WRITE_OP_CB cb, void* cb_data); 44 static void WriteDescriptor(tCONN_ID conn_id, uint16_t handle, std::vector<uint8_t> value, 45 tGATT_WRITE_TYPE write_type, GATT_WRITE_OP_CB cb, void* cb_data); 46 static void ConfigureMtu(tCONN_ID conn_id, uint16_t mtu); 47 /* This method queues "Read Multiple Variable Length Characteristic Values". 48 * Remote must support this method when it supports EATT. 49 * Returns true when remote supports EATT and operation was successfully queued. 50 * Returns false when remote doesn't support EATT and operation was not scheduled. 51 */ 52 static bool ReadMultiCharacteristic(tCONN_ID conn_id, tBTA_GATTC_MULTI& p_read_multi, 53 GATT_READ_MULTI_OP_CB cb, void* cb_data); 54 55 /* Holds pending GATT operations */ 56 struct gatt_operation { 57 uint8_t type; 58 uint16_t handle; 59 tBTA_GATTC_MULTI handles; 60 GATT_READ_OP_CB read_cb; 61 GATT_READ_MULTI_OP_CB read_multi_cb; 62 void* read_cb_data; 63 GATT_WRITE_OP_CB write_cb; 64 void* write_cb_data; 65 GATT_CONFIGURE_MTU_OP_CB mtu_cb; 66 void* mtu_cb_data; 67 68 /* write-specific fields */ 69 tGATT_WRITE_TYPE write_type; 70 std::vector<uint8_t> value; 71 }; 72 73 private: 74 static void mark_as_not_executing(tCONN_ID conn_id); 75 static void gatt_execute_next_op(tCONN_ID conn_id); 76 static void gatt_read_op_finished(tCONN_ID conn_id, tGATT_STATUS status, uint16_t handle, 77 uint16_t len, uint8_t* value, void* data); 78 static void gatt_write_op_finished(tCONN_ID conn_id, tGATT_STATUS status, uint16_t handle, 79 uint16_t len, const uint8_t* value, void* data); 80 static void gatt_configure_mtu_op_finished(tCONN_ID conn_id, tGATT_STATUS status, void* data); 81 static void gatt_read_multi_op_finished(tCONN_ID conn_id, tGATT_STATUS status, 82 tBTA_GATTC_MULTI& handle, uint16_t len, uint8_t* value, 83 void* data); 84 // maps connection id to operations waiting for execution 85 static std::unordered_map<tCONN_ID, std::list<gatt_operation>> gatt_op_queue; 86 // contain connection ids that currently execute operations 87 static std::unordered_set<tCONN_ID> gatt_op_queue_executing; 88 }; 89