From 69c5ef96659bcc734c66d12a45f6ae050b128f47 Mon Sep 17 00:00:00 2001
From: Lucas Romero <luqasn@gmail.com>
Date: Tue, 11 Jun 2024 10:47:10 +0200
Subject: [PATCH] lorawan: services: frag transport: prepare for pluggable
 decoder

by wrapping decoder implementation specific bits in #ifdefs

Signed-off-by: Lucas Romero <luqasn@gmail.com>
---
 modules/loramac-node/CMakeLists.txt      |  2 +-
 subsys/lorawan/services/Kconfig          | 12 ++++++++++++
 subsys/lorawan/services/frag_transport.c | 25 ++++++++++++++++++++----
 3 files changed, 34 insertions(+), 5 deletions(-)

diff --git a/modules/loramac-node/CMakeLists.txt b/modules/loramac-node/CMakeLists.txt
index 9e0bdbc9877..a711ab3e5fe 100644
--- a/modules/loramac-node/CMakeLists.txt
+++ b/modules/loramac-node/CMakeLists.txt
@@ -55,7 +55,7 @@ zephyr_library_sources_ifdef(CONFIG_HAS_SEMTECH_LORAMAC
   ${ZEPHYR_LORAMAC_NODE_MODULE_DIR}/src/mac/LoRaMacSerializer.c
 )
 
-zephyr_library_sources_ifdef(CONFIG_LORAWAN_FRAG_TRANSPORT
+zephyr_library_sources_ifdef(CONFIG_LORAWAN_FRAG_TRANSPORT_DECODER_SEMTECH
   ${ZEPHYR_LORAMAC_NODE_MODULE_DIR}/src/apps/LoRaMac/common/LmHandler/packages/FragDecoder.c
 )
 
diff --git a/subsys/lorawan/services/Kconfig b/subsys/lorawan/services/Kconfig
index 95905a7cbff..591ba3ad60a 100644
--- a/subsys/lorawan/services/Kconfig
+++ b/subsys/lorawan/services/Kconfig
@@ -65,6 +65,18 @@ config LORAWAN_FRAG_TRANSPORT
 
 	  The used default port for this service is 201.
 
+choice LORAWAN_FRAG_TRANSPORT_DECODER
+	bool "Fragmented Data Block Transport decoder implementation"
+	depends on LORAWAN_FRAG_TRANSPORT
+	default LORAWAN_FRAG_TRANSPORT_DECODER_SEMTECH
+
+config LORAWAN_FRAG_TRANSPORT_DECODER_SEMTECH
+	bool "Semtech"
+	help
+	  The default decoder implementation from LoRaMAC-node.
+
+endchoice # LORAWAN_FRAG_TRANSPORT_DECODER
+
 DT_CHOSEN_Z_CODE_PARTITION := zephyr,code-partition
 
 config LORAWAN_FRAG_TRANSPORT_IMAGE_SIZE
diff --git a/subsys/lorawan/services/frag_transport.c b/subsys/lorawan/services/frag_transport.c
index 73055461a90..2efe5213992 100644
--- a/subsys/lorawan/services/frag_transport.c
+++ b/subsys/lorawan/services/frag_transport.c
@@ -13,7 +13,10 @@
 #include "lorawan_services.h"
 
 #include <LoRaMac.h>
+#ifdef CONFIG_LORAWAN_FRAG_TRANSPORT_DECODER_SEMTECH
 #include <FragDecoder.h>
+#endif
+
 #include <zephyr/lorawan/lorawan.h>
 #include <zephyr/logging/log.h>
 #include <zephyr/random/random.h>
@@ -79,8 +82,10 @@ struct frag_transport_context {
 	/** Application-specific descriptor for the data block, e.g. firmware version */
 	uint32_t descriptor;
 
+#ifdef CONFIG_LORAWAN_FRAG_TRANSPORT_DECODER_SEMTECH
 	/* variables required for FragDecoder.h */
 	FragDecoderCallbacks_t decoder_callbacks;
+#endif
 };
 
 /*
@@ -127,8 +132,11 @@ static void frag_transport_package_callback(uint8_t port, bool data_pending, int
 
 			uint8_t missing_frag = CLAMP(ctx.nb_frag - ctx.nb_frag_received, 0, 255);
 
+			uint8_t memory_error = 0;
+#ifdef CONFIG_LORAWAN_FRAG_TRANSPORT_DECODER_SEMTECH
 			FragDecoderStatus_t decoder_status = FragDecoderGetStatus();
-			uint8_t memory_error = decoder_status.MatrixError;
+			memory_error = decoder_status.MatrixError;
+#endif
 
 			if (participants == 1 || missing_frag > 0) {
 				tx_buf[tx_pos++] = FRAG_TRANSPORT_CMD_FRAG_STATUS;
@@ -183,15 +191,22 @@ static void frag_transport_package_callback(uint8_t port, bool data_pending, int
 				status |= BIT(0);
 			}
 
-			if (ctx.nb_frag > FRAG_MAX_NB || ctx.frag_size > FRAG_MAX_SIZE ||
-			    ctx.nb_frag * ctx.frag_size > FragDecoderGetMaxFileSize()) {
+			if (ctx.nb_frag > FRAG_MAX_NB || ctx.frag_size > FRAG_MAX_SIZE) {
 				/* Not enough memory */
 				status |= BIT(1);
 			}
 
+#ifdef CONFIG_LORAWAN_FRAG_TRANSPORT_DECODER_SEMTECH
+			if (ctx.nb_frag * ctx.frag_size > FragDecoderGetMaxFileSize()) {
+				/* Not enough memory */
+				status |= BIT(1);
+			}
+#endif
+
 			/* Descriptor not used: Ignore Wrong Descriptor error */
 
 			if ((status & 0x1F) == 0) {
+#ifdef CONFIG_LORAWAN_FRAG_TRANSPORT_DECODER_SEMTECH
 				/*
 				 * Assign callbacks after initialization to prevent the FragDecoder
 				 * from writing byte-wise 0xFF to the entire flash. Instead, erase
@@ -204,7 +219,7 @@ static void frag_transport_package_callback(uint8_t port, bool data_pending, int
 
 				ctx.decoder_callbacks.FragDecoderWrite = frag_flash_write;
 				ctx.decoder_callbacks.FragDecoderRead = frag_flash_read;
-
+#endif
 				frag_flash_init(ctx.frag_size);
 				ctx.is_active = true;
 			}
@@ -251,8 +266,10 @@ static void frag_transport_package_callback(uint8_t port, bool data_pending, int
 				frag_flash_use_cache();
 			}
 
+#ifdef CONFIG_LORAWAN_FRAG_TRANSPORT_DECODER_SEMTECH
 			decoder_process_status = FragDecoderProcess(
 				frag_counter, (uint8_t *)&rx_buf[rx_pos]);
+#endif
 
 			LOG_INF("DataFragment %u of %u (%u lost), session: %u, decoder result: %d",
 				frag_counter, ctx.nb_frag, frag_counter - ctx.nb_frag_received,