1*05767d91SRobert Wu /* 2*05767d91SRobert Wu * Copyright (C) 2017 The Android Open Source Project 3*05767d91SRobert Wu * 4*05767d91SRobert Wu * Licensed under the Apache License, Version 2.0 (the "License"); 5*05767d91SRobert Wu * you may not use this file except in compliance with the License. 6*05767d91SRobert Wu * You may obtain a copy of the License at 7*05767d91SRobert Wu * 8*05767d91SRobert Wu * http://www.apache.org/licenses/LICENSE-2.0 9*05767d91SRobert Wu * 10*05767d91SRobert Wu * Unless required by applicable law or agreed to in writing, software 11*05767d91SRobert Wu * distributed under the License is distributed on an "AS IS" BASIS, 12*05767d91SRobert Wu * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13*05767d91SRobert Wu * See the License for the specific language governing permissions and 14*05767d91SRobert Wu * limitations under the License. 15*05767d91SRobert Wu */ 16*05767d91SRobert Wu 17*05767d91SRobert Wu #ifndef AAUDIO_FIXED_BLOCK_ADAPTER_H 18*05767d91SRobert Wu #define AAUDIO_FIXED_BLOCK_ADAPTER_H 19*05767d91SRobert Wu 20*05767d91SRobert Wu #include <memory> 21*05767d91SRobert Wu #include <stdint.h> 22*05767d91SRobert Wu #include <sys/types.h> 23*05767d91SRobert Wu 24*05767d91SRobert Wu /** 25*05767d91SRobert Wu * Interface for a class that needs fixed-size blocks. 26*05767d91SRobert Wu */ 27*05767d91SRobert Wu class FixedBlockProcessor { 28*05767d91SRobert Wu public: 29*05767d91SRobert Wu virtual ~FixedBlockProcessor() = default; 30*05767d91SRobert Wu /** 31*05767d91SRobert Wu * 32*05767d91SRobert Wu * @param buffer Pointer to first byte of data. 33*05767d91SRobert Wu * @param numBytes This will be a fixed size specified in FixedBlockAdapter::open(). 34*05767d91SRobert Wu * @return Number of bytes processed or a negative error code. 35*05767d91SRobert Wu */ 36*05767d91SRobert Wu virtual int32_t onProcessFixedBlock(uint8_t *buffer, int32_t numBytes) = 0; 37*05767d91SRobert Wu }; 38*05767d91SRobert Wu 39*05767d91SRobert Wu /** 40*05767d91SRobert Wu * Base class for a variable-to-fixed-size block adapter. 41*05767d91SRobert Wu */ 42*05767d91SRobert Wu class FixedBlockAdapter 43*05767d91SRobert Wu { 44*05767d91SRobert Wu public: FixedBlockAdapter(FixedBlockProcessor & fixedBlockProcessor)45*05767d91SRobert Wu FixedBlockAdapter(FixedBlockProcessor &fixedBlockProcessor) 46*05767d91SRobert Wu : mFixedBlockProcessor(fixedBlockProcessor) {} 47*05767d91SRobert Wu 48*05767d91SRobert Wu virtual ~FixedBlockAdapter(); 49*05767d91SRobert Wu 50*05767d91SRobert Wu /** 51*05767d91SRobert Wu * Allocate internal resources needed for buffering data. 52*05767d91SRobert Wu */ 53*05767d91SRobert Wu virtual int32_t open(int32_t bytesPerFixedBlock); 54*05767d91SRobert Wu 55*05767d91SRobert Wu /** 56*05767d91SRobert Wu * Free internal resources. 57*05767d91SRobert Wu */ 58*05767d91SRobert Wu int32_t close(); 59*05767d91SRobert Wu 60*05767d91SRobert Wu protected: 61*05767d91SRobert Wu FixedBlockProcessor &mFixedBlockProcessor; 62*05767d91SRobert Wu std::unique_ptr<uint8_t[]> mStorage; // Store data here while assembling buffers. 63*05767d91SRobert Wu int32_t mSize = 0; // Size in bytes of the fixed size buffer. 64*05767d91SRobert Wu int32_t mPosition = 0; // Offset of the last byte read or written. 65*05767d91SRobert Wu }; 66*05767d91SRobert Wu 67*05767d91SRobert Wu #endif /* AAUDIO_FIXED_BLOCK_ADAPTER_H */ 68