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Diffstat (limited to 'src/lib/decoder/fire_crc.c')
-rw-r--r--src/lib/decoder/fire_crc.c179
1 files changed, 0 insertions, 179 deletions
diff --git a/src/lib/decoder/fire_crc.c b/src/lib/decoder/fire_crc.c
deleted file mode 100644
index 7cdfc0b..0000000
--- a/src/lib/decoder/fire_crc.c
+++ /dev/null
@@ -1,179 +0,0 @@
-//TODO: this file shouldn't be part of the GSM Receiver
-/* -*- c++ -*- */
-/*
- * Copyright 2005 Free Software Foundation, Inc.
- *
- * This file is part of GNU Radio
- *
- * GNU Radio is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2, or (at your option)
- * any later version.
- *
- * GNU Radio is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with GNU Radio; see the file COPYING. If not, write to
- * the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- * Boston, MA 02111-1307, USA.
- */
-
-#include "fire_crc.h"
-#include <stdio.h>
-#include <string.h>
-
-#define REM(x, y) (x) % (y)
-
-static int FC_syndrome_shift(FC_CTX *ctx, unsigned int bit);
-
-static int
-outit(int *data, int len)
-{
- int i;
-
- for (i = 0; i < len; i++)
- printf("%d ", data[i]);
- printf("\n");
-}
-
-int
-FC_init(FC_CTX *ctx, unsigned int crc_size, unsigned int data_size)
-{
- ctx->crc_size = crc_size;
- ctx->data_size = data_size;
- ctx->syn_start = 0;
-
- return 0;
-}
-
-int
-FC_check_crc(FC_CTX *ctx, unsigned char *input_bits, unsigned char *control_data)
-{
- int j,error_count = 0, error_index = 0, success_flag = 0, syn_index = 0;
- unsigned int i;
-
- ctx->syn_start = 0;
- // reset the syndrome register
- memset(ctx->syndrome_reg, 0, sizeof ctx->syndrome_reg);
-
- // shift in the data bits
- for (i=0; i < ctx->data_size; i++) {
- error_count = FC_syndrome_shift(ctx, input_bits[i]);
- control_data[i] = input_bits[i];
- }
-
- // shift in the crc bits
- for (i=0; i < ctx->crc_size; i++) {
- error_count = FC_syndrome_shift(ctx, 1-input_bits[i+ctx->data_size]);
- }
-
- // Find position of error burst
- if (error_count == 0) {
- error_index = 0;
- }
- else {
- error_index = 1;
- error_count = FC_syndrome_shift(ctx, 0);
- error_index += 1;
- while (error_index < (ctx->data_size + ctx->crc_size) ) {
- error_count = FC_syndrome_shift(ctx, 0);
- error_index += 1;
- if ( error_count == 0 ) break;
- }
- }
-
- // Test for correctable errors
- //printf("error_index %d\n",error_index);
- if (error_index == 224) success_flag = 0;
- else {
-
- // correct index depending on the position of the error
- if (error_index == 0) syn_index = error_index;
- else syn_index = error_index - 1;
-
- // error burst lies within data bits
- if (error_index < 184) {
- //printf("error < bit 184,%d\n",error_index);
- j = error_index;
- while ( j < (error_index+12) ) {
- if (j < 184) {
- control_data[j] = control_data[j] ^
- ctx->syndrome_reg[REM(ctx->syn_start+39-j+syn_index,40)];
- }
- else break;
- j = j + 1;
- }
- }
- else if ( error_index > 212 ) {
- //printf("error > bit 212,%d\n",error_index);
- j = 0;
- while ( j < (error_index - 212) ) {
- control_data[j] = control_data[j] ^
- ctx->syndrome_reg[REM(ctx->syn_start+39-j-224+syn_index,40)];
- j = j + 1;
- }
- }
- // for 183 < error_index < 213 error in parity alone so ignore
- success_flag = 1;
- }
- return success_flag;
-}
-
-static int
-FC_syndrome_shift(FC_CTX *ctx, unsigned int bit)
-{
- int error_count = 0;
- unsigned int i;
-
- if (ctx->syn_start == 0)
- ctx->syn_start = 39;
- else ctx->syn_start -= 1;
-
- int temp_syndrome_reg[sizeof ctx->syndrome_reg];
-
- memcpy(temp_syndrome_reg, ctx->syndrome_reg, sizeof temp_syndrome_reg);
-
- temp_syndrome_reg[REM(ctx->syn_start+3,40)] =
- ctx->syndrome_reg[REM(ctx->syn_start+3,40)] ^
- ctx->syndrome_reg[ctx->syn_start];
- temp_syndrome_reg[REM(ctx->syn_start+17,40)] =
- ctx->syndrome_reg[REM(ctx->syn_start+17,40)] ^
- ctx->syndrome_reg[ctx->syn_start];
- temp_syndrome_reg[REM(ctx->syn_start+23,40)] =
- ctx->syndrome_reg[REM(ctx->syn_start+23,40)] ^
- ctx->syndrome_reg[ctx->syn_start];
- temp_syndrome_reg[REM(ctx->syn_start+26,40)] =
- ctx->syndrome_reg[REM(ctx->syn_start+26,40)] ^
- ctx->syndrome_reg[ctx->syn_start];
-
- temp_syndrome_reg[REM(ctx->syn_start+4,40)] =
- ctx->syndrome_reg[REM(ctx->syn_start+4,40)] ^ bit;
- temp_syndrome_reg[REM(ctx->syn_start+6,40)] =
- ctx->syndrome_reg[REM(ctx->syn_start+6,40)] ^ bit;
- temp_syndrome_reg[REM(ctx->syn_start+10,40)] =
- ctx->syndrome_reg[REM(ctx->syn_start+10,40)] ^ bit;
- temp_syndrome_reg[REM(ctx->syn_start+16,40)] =
- ctx->syndrome_reg[REM(ctx->syn_start+16,40)] ^ bit;
- temp_syndrome_reg[REM(ctx->syn_start+27,40)] =
- ctx->syndrome_reg[REM(ctx->syn_start+27,40)] ^ bit;
- temp_syndrome_reg[REM(ctx->syn_start+29,40)] =
- ctx->syndrome_reg[REM(ctx->syn_start+29,40)] ^ bit;
- temp_syndrome_reg[REM(ctx->syn_start+33,40)] =
- ctx->syndrome_reg[REM(ctx->syn_start+33,40)] ^ bit;
- temp_syndrome_reg[REM(ctx->syn_start+39,40)] =
- ctx->syndrome_reg[REM(ctx->syn_start+39,40)] ^ bit;
-
- temp_syndrome_reg[ctx->syn_start] = ctx->syndrome_reg[ctx->syn_start] ^ bit;
-
- memcpy(ctx->syndrome_reg, temp_syndrome_reg, sizeof ctx->syndrome_reg);
-
- for (i = 0; i < 28; i++) {
- error_count = error_count + ctx->syndrome_reg[REM(ctx->syn_start+i,40)];
- }
- return error_count;
-}
-
-
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