1 /* 2 * Copyright (c) 2024 A Labs GmbH 3 * Copyright (c) 2024 tado GmbH 4 * Copyright (c) 2022 Jiapeng Li 5 * 6 * Based on: https://github.com/JiapengLi/LoRaWANFragmentedDataBlockTransportAlgorithm 7 * Original algorithm: http://www.inference.org.uk/mackay/gallager/papers/ldpc.pdf 8 * 9 * SPDX-License-Identifier: Apache-2.0 10 */ 11 12 #ifndef FRAG_DEC_H_ 13 #define FRAG_DEC_H_ 14 15 #include <stdint.h> 16 #include <stddef.h> 17 18 #define FRAG_MAX_NB \ 19 (CONFIG_LORAWAN_FRAG_TRANSPORT_IMAGE_SIZE / CONFIG_LORAWAN_FRAG_TRANSPORT_MIN_FRAG_SIZE + \ 20 1U) 21 #define FRAG_MAX_SIZE (CONFIG_LORAWAN_FRAG_TRANSPORT_MAX_FRAG_SIZE) 22 #define FRAG_TOLERANCE (FRAG_MAX_NB * CONFIG_LORAWAN_FRAG_TRANSPORT_MAX_REDUNDANCY / 100U) 23 24 #define FRAG_DEC_ONGOING (-1) 25 #define FRAG_DEC_ERR_INVALID_FRAME (-2) 26 #define FRAG_DEC_ERR_TOO_MANY_FRAMES_LOST (-3) 27 #define FRAG_DEC_ERR (-4) 28 29 enum frag_decoder_status { 30 /** Processing uncoded fragments */ 31 FRAG_DEC_STA_UNCODED, 32 /** Processing coded fragments and restoring data with the help of other fragments */ 33 FRAG_DEC_STA_CODED, 34 /** All fragments received and/or restored */ 35 FRAG_DEC_STA_DONE, 36 }; 37 38 struct frag_decoder { 39 /** Current decoder status */ 40 enum frag_decoder_status status; 41 42 /** Number of fragments */ 43 uint16_t nb_frag; 44 /** Size of individual fragment */ 45 uint8_t frag_size; 46 47 /** Number of frames lost in this session */ 48 uint16_t lost_frame_count; 49 /** Number of frames recovered in this session */ 50 uint16_t filled_lost_frame_count; 51 }; 52 53 void frag_dec_init(struct frag_decoder *decoder, size_t nb_frag, size_t frag_size); 54 int frag_dec(struct frag_decoder *decoder, uint16_t frag_counter, const uint8_t *buf, size_t len); 55 56 #endif /* FRAG_DEC_H_ */ 57
