edge: Add unified decoder methods for GPRS/EGPRS

This commit adds new RLC block decoder functions that support both
GPRS and EGPRS. The code path is selected based on the value of the
GprsCodingScheme cs object.

- rlc_parse_ul_data_header
        parses the header of an RLC data block including the E and FBI/TI
        flags (currently supported CS-1 - CS-4, MCS-1 - MCS-4).

- rlc_copy_to_aligned_buffer
        copies an RLC data unit to a byte aligned buffer and returns
        the unit's length.

- rlc_get_data_aligned
        is a convenience wrapper around rlc_copy_to_aligned_buffer
        that avoids copying if the data unit is already byte aligned.

Sponsored-by: On-Waves ehf

1 files changed, 22 insertions, 0 deletions

diff --git a/src/decoding.h b/src/decoding.h
index 03dad47e..1cda7b42 100644
--- a/src/decoding.h
+++ b/src/decoding.h
@@ -20,15 +20,37 @@
 #pragma once
 
 #include <gsm_rlcmac.h>
+#include "rlc.h"
 
 #include <stdint.h>
 
 class Decoding {
 public:
+	struct RlcData {
+		uint8_t	offset;
+		uint8_t	length;
+		bool	is_complete;
+	};
+
 	static int tlli_from_ul_data(const uint8_t *data, uint8_t len,
 					uint32_t *tlli);
+	static int rlc_data_from_ul_data(
+		const struct gprs_rlc_ul_data_block_info *rdbi,
+		GprsCodingScheme cs, const uint8_t *data, RlcData *chunks,
+		unsigned int chunks_size, uint32_t *tlli);
 	static uint8_t get_ms_class_by_capability(MS_Radio_Access_capability_t *cap);
 	static uint8_t get_egprs_ms_class_by_capability(MS_Radio_Access_capability_t *cap);
 
 	static void extract_rbb(const uint8_t *rbb, char *extracted_rbb);
+
+	static int rlc_parse_ul_data_header(struct gprs_rlc_ul_header_egprs *rlc,
+		const uint8_t *data, GprsCodingScheme cs);
+	static unsigned int rlc_copy_to_aligned_buffer(
+		const struct gprs_rlc_ul_header_egprs *rlc,
+		unsigned int data_block_idx,
+		const uint8_t *src, uint8_t *buffer);
+	static const uint8_t *rlc_get_data_aligned(
+		const struct gprs_rlc_ul_header_egprs *rlc,
+		unsigned int data_block_idx,
+		const uint8_t *src, uint8_t *buffer);
 };