[PATCH 1/2] Add concolutional code generator for *CCH

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msuraev at sysmocom.de msuraev at sysmocom.de
Wed Apr 6 11:05:29 UTC 2016


From: Max <msuraev at sysmocom.de>

Move convolutional code for *CCH channels from test to public API
because it's useful not only for testing.
---
 include/Makefile.am             |  1 +
 include/osmocom/core/conv.h     |  2 +-
 include/osmocom/core/conv_gen.h | 46 +++++++++++++++++++++++++++++++
 src/Makefile.am                 |  4 +--
 src/conv_xcch_gen.c             | 61 +++++++++++++++++++++++++++++++++++++++++
 tests/conv/conv_test.c          | 31 ++-------------------
 6 files changed, 114 insertions(+), 31 deletions(-)
 create mode 100644 include/osmocom/core/conv_gen.h
 create mode 100644 src/conv_xcch_gen.c

diff --git a/include/Makefile.am b/include/Makefile.am
index 0e5ed74..7c10a72 100644
--- a/include/Makefile.am
+++ b/include/Makefile.am
@@ -9,6 +9,7 @@ nobase_include_HEADERS = \
                        osmocom/core/bitvec.h \
                        osmocom/core/bitcomp.h \
                        osmocom/core/conv.h \
+                       osmocom/core/conv_gen.h \
                        osmocom/core/crc16.h \
                        osmocom/core/crc16gen.h \
                        osmocom/core/crc32gen.h \
diff --git a/include/osmocom/core/conv.h b/include/osmocom/core/conv.h
index e7f6bd6..42807fa 100644
--- a/include/osmocom/core/conv.h
+++ b/include/osmocom/core/conv.h
@@ -139,5 +139,5 @@ int osmo_conv_decode_get_output(struct osmo_conv_decoder *decoder,
 int osmo_conv_decode(const struct osmo_conv_code *code,
                      const sbit_t *input, ubit_t *output);
 
-
+#include <osmocom/core/conv_gen.h>
 /*! @} */
diff --git a/include/osmocom/core/conv_gen.h b/include/osmocom/core/conv_gen.h
new file mode 100644
index 0000000..e4f1b65
--- /dev/null
+++ b/include/osmocom/core/conv_gen.h
@@ -0,0 +1,46 @@
+/*
+ * conv_gen.h
+ *
+ * Copyright (C) 2016 sysmocom s.f.m.c. GmbH
+ *
+ * All Rights Reserved
+ *
+ * This program 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 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#pragma once
+
+extern const uint8_t osmo_conv_gsm0503_xcch_output[][2];
+extern const uint8_t osmo_conv_gsm0503_xcch_state[][2];
+
+/*! \file conv_gen.h
+ * Osmocom convolutional encoder/decoder for xCCH channels, see 3GPP TS 05.03
+ */
+
+/*! \brief structure describing convolutional code xCCH
+ *
+ *  Non-recursive code, flushed, not punctured code.
+ *  Generator polynomials:
+ *  G0 = 1 + D3 + D4
+ *  G1 = 1 + D + D3 + D4
+ */
+static const struct osmo_conv_code osmo_conv_gsm0503_xcch = {
+	.N = 2,
+	.K = 5,
+	.len = 224,
+	.term = CONV_TERM_FLUSH,
+	.next_output = osmo_conv_gsm0503_xcch_output,
+	.next_state  = osmo_conv_gsm0503_xcch_state,
+};
diff --git a/src/Makefile.am b/src/Makefile.am
index 45a77e3..2555ff8 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -10,14 +10,14 @@ lib_LTLIBRARIES = libosmocore.la
 libosmocore_la_LIBADD = $(BACKTRACE_LIB) $(TALLOC_LIBS)
 libosmocore_la_SOURCES = timer.c select.c signal.c msgb.c bits.c \
 			 bitvec.c bitcomp.c statistics.c \
-			 write_queue.c utils.c socket.c \
+			 conv_xcch_gen.c write_queue.c utils.c socket.c \
 			 logging.c logging_syslog.c rate_ctr.c \
 			 gsmtap_util.c crc16.c panic.c backtrace.c \
 			 conv.c application.c rbtree.c strrb.c \
 			 loggingrb.c crc8gen.c crc16gen.c crc32gen.c crc64gen.c \
 			 macaddr.c stat_item.c stats.c stats_statsd.c prim.c
 
-BUILT_SOURCES = crc8gen.c crc16gen.c crc32gen.c crc64gen.c
+BUILT_SOURCES = crc8gen.c crc16gen.c crc32gen.c crc64gen.c conv_xcch_gen.c
 
 if ENABLE_PLUGIN
 libosmocore_la_SOURCES += plugin.c
diff --git a/src/conv_xcch_gen.c b/src/conv_xcch_gen.c
new file mode 100644
index 0000000..b948e7b
--- /dev/null
+++ b/src/conv_xcch_gen.c
@@ -0,0 +1,61 @@
+/*
+ * conv_xcch_gen.c
+ *
+ * Copyright (C) 2016 sysmocom s.f.m.c. GmbH
+ *
+ * All Rights Reserved
+ *
+ * This program 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 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <stdint.h>
+
+const uint8_t osmo_conv_gsm0503_xcch_output[][2] = {
+	{ 0, 3 },
+	{ 3, 0 },
+	{ 3, 0 },
+	{ 0, 3 },
+	{ 0, 3 },
+	{ 3, 0 },
+	{ 3, 0 },
+	{ 0, 3 },
+	{ 1, 2 },
+	{ 2, 1 },
+	{ 2, 1 },
+	{ 1, 2 },
+	{ 1, 2 },
+	{ 2, 1 },
+	{ 2, 1 },
+	{ 1, 2 },
+};
+
+const uint8_t osmo_conv_gsm0503_xcch_state[][2] = {
+	{ 0,  8 },
+	{ 0,  8 },
+	{ 1,  9 },
+	{ 1,  9 },
+	{ 2, 10 },
+	{ 2, 10 },
+	{ 3, 11 },
+	{ 3, 11 },
+	{ 4, 12 },
+	{ 4, 12 },
+	{ 5, 13 },
+	{ 5, 13 },
+	{ 6, 14 },
+	{ 6, 14 },
+	{ 7, 15 },
+	{ 7, 15 },
+};
diff --git a/tests/conv/conv_test.c b/tests/conv/conv_test.c
index de62f23..baebdbe 100644
--- a/tests/conv/conv_test.c
+++ b/tests/conv/conv_test.c
@@ -15,31 +15,6 @@
 /* Test codes                                                               */
 /* ------------------------------------------------------------------------ */
 
-/* GSM xCCH -> Non-recursive code, flushed, not punctured */
-static const uint8_t conv_gsm_xcch_next_output[][2] = {
-	{ 0, 3 }, { 1, 2 }, { 0, 3 }, { 1, 2 },
-	{ 3, 0 }, { 2, 1 }, { 3, 0 }, { 2, 1 },
-	{ 3, 0 }, { 2, 1 }, { 3, 0 }, { 2, 1 },
-	{ 0, 3 }, { 1, 2 }, { 0, 3 }, { 1, 2 },
-};
-
-static const uint8_t conv_gsm_xcch_next_state[][2] = {
-	{  0,  1 }, {  2,  3 }, {  4,  5 }, {  6,  7 },
-	{  8,  9 }, { 10, 11 }, { 12, 13 }, { 14, 15 },
-	{  0,  1 }, {  2,  3 }, {  4,  5 }, {  6,  7 },
-	{  8,  9 }, { 10, 11 }, { 12, 13 }, { 14, 15 },
-};
-
-static const struct osmo_conv_code conv_gsm_xcch = {
-	.N = 2,
-	.K = 5,
-	.len = 224,
-	.term = CONV_TERM_FLUSH,
-	.next_output = conv_gsm_xcch_next_output,
-	.next_state  = conv_gsm_xcch_next_state,
-};
-
-
 /* GSM TCH/AFS 7.95 -> Recursive code, flushed, with puncturing */
 static const uint8_t conv_gsm_tch_afs_7_95_next_output[][2] = {
 	{ 0, 7 }, { 3, 4 }, { 2, 5 }, { 1, 6 },
@@ -227,8 +202,8 @@ static const struct osmo_conv_code conv_trunc = {
 	.K = 5,
 	.len = 224,
 	.term = CONV_TERM_TRUNCATION,
-	.next_output = conv_gsm_xcch_next_output,
-	.next_state  = conv_gsm_xcch_next_state,
+	.next_output = osmo_conv_gsm0503_xcch_output,
+	.next_state  = osmo_conv_gsm0503_xcch_state,
 };
 
 
@@ -249,7 +224,7 @@ struct conv_test_vector {
 static const struct conv_test_vector tests[] = {
 	{
 		.name = "GSM xCCH (non-recursive, flushed, not punctured)",
-		.code = &conv_gsm_xcch,
+		.code = &osmo_conv_gsm0503_xcch,
 		.in_len  = 224,
 		.out_len = 456,
 		.has_vec = 1,
-- 
2.8.1




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