[M] Change in libosmocore[master]: coding: test FACCH/[FH] bitstealing in test_csd()

25 May 2023

fixeria has submitted this change. ( https://gerrit.osmocom.org/c/libosmocore/+/33004 )
Change subject: coding: test FACCH/[FH] bitstealing in test_csd()
......................................................................
coding: test FACCH/[FH] bitstealing in test_csd()
In test_csd() we encode three data frames filled-in with three specific
patterns and then try decoding them.  Additionally execute the same set
of tests, but with FACCH/[FH] bitstealing (pattern 0x2b).
As can be seen from the test output, we have problems decoding FACCH:
* FACCH/F: decoding fails (n_errors=0 / n_bits_total=0),
* FACCH/H: decoding with errors (n_errors=2 / n_bits_total=456).
A patch fixing the problem follows.
Change-Id: Idc6decec3b84981d2aab4e27caab9ad65180f945
Related: OS#1572
---
M tests/coding/coding_test.c
M tests/coding/coding_test.ok
2 files changed, 148 insertions(+), 6 deletions(-)
Approvals:
  Jenkins Builder: Verified
  laforge: Looks good to me, but someone else must approve
  pespin: Looks good to me, but someone else must approve
  falconia: Looks good to me, approved

diff --git a/tests/coding/coding_test.c b/tests/coding/coding_test.c
index e8dbe83..e53c8ad 100644
--- a/tests/coding/coding_test.c
+++ b/tests/coding/coding_test.c
@@ -540,6 +540,7 @@
    unsigned int num_bits;
    int (*enc_fn)(ubit_t *out, const ubit_t *in);
    int (*dec_fn)(ubit_t *out, const sbit_t *in, int *ne, int *nb);
+	bool half_rate;
 };
static const struct csd_test_case csd_tests[] = {
@@ -560,12 +561,14 @@
    	.num_bits = 4 * 60,
    	.enc_fn = &gsm0503_tch_hr48_encode,
    	.dec_fn = &gsm0503_tch_hr48_decode,
+		.half_rate = true,
    },
    {
    	.name = "TCH/H2.4",
    	.num_bits = 2 * 72,
    	.enc_fn = &gsm0503_tch_hr24_encode,
    	.dec_fn = &gsm0503_tch_hr24_decode,
+		.half_rate = true,
    },
    {
    	.name = "TCH/F14.4",
@@ -575,7 +578,7 @@
    },
 };
-static void test_csd(const struct csd_test_case *tc)
+static void test_csd(const struct csd_test_case *tc, bool facch)
 {
    const uint8_t patterns[] = { 0x00, 0xaa, 0xff };
    ubit_t bursts_u[116 * (22 + 8)] = { 0 };
@@ -590,9 +593,17 @@
rc = tc->enc_fn(&bursts_u[i * 4 * 116], &data[0]);
    	CHECK_RC_OR_RET(rc == 0, "encoding");
-	}
-	/* TODO: test FACCH stealing */
+		/* Test FACCH bitstealing */
+		if (facch && i == 1) {
+			memset(&data, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN);
+			if (tc->half_rate)
+				rc = gsm0503_tch_hr_facch_encode(&bursts_u[116 * 4], &data[0]);
+			else
+				rc = gsm0503_tch_fr_facch_encode(&bursts_u[116 * 4], &data[0]);
+			CHECK_RC_OR_RET(rc == 0, "encoding FACCH");
+		}
+	}
/* Prepare soft-bits */
    osmo_ubit2sbit(&bursts_s[0], &bursts_u[0], sizeof(bursts_s));
@@ -618,6 +629,27 @@
    	printf("\n");
    }
+	/* Test FACCH bitstealing if requested */
+	if (facch) {
+		int n_errors = 0, n_bits_total = 0;
+
+		if (tc->half_rate) {
+			rc = gsm0503_tch_hr_facch_decode(&data[0], &bursts_s[116 * 4],
+							 &n_errors, &n_bits_total);
+		} else {
+			rc = gsm0503_tch_fr_facch_decode(&data[0], &bursts_s[116 * 4],
+							 &n_errors, &n_bits_total);
+		}
+#if 0
+		/* FIXME: there's something wrong with CSD mapping */
+		CHECK_RC_OR_RET(rc == GSM_MACBLOCK_LEN, "decoding FACCH");
+#endif
+
+		printf("%s(%s): FACCH/%c (pattern 0x2b): n_errors=%d / n_bits_total=%d\n",
+		       __func__, tc->name, tc->half_rate ? 'H' : 'F', n_errors, n_bits_total);
+		printf("%s\n", osmo_hexdump(&data[0], GSM_MACBLOCK_LEN));
+	}
+
    printf("\n");
 }
@@ -688,9 +720,12 @@
    for (i = 0; i < ARRAY_SIZE(test_l2); i++)
    	test_facch(test_l2[i], true);
-	printf("\nTesting CSD functions:\n");
+	printf("\nTesting CSD functions (no FACCH):\n");
    for (i = 0; i < ARRAY_SIZE(csd_tests); i++)
-		test_csd(&csd_tests[i]);
+		test_csd(&csd_tests[i], false);
+	printf("\nTesting CSD functions (with FACCH):\n");
+	for (i = 0; i < ARRAY_SIZE(csd_tests); i++)
+		test_csd(&csd_tests[i], true);
printf("Success\n");
diff --git a/tests/coding/coding_test.ok b/tests/coding/coding_test.ok
index 3985513..c9c6bb7 100644
--- a/tests/coding/coding_test.ok
+++ b/tests/coding/coding_test.ok
@@ -402,7 +402,7 @@
 test_facch(FACCH/H): decoded (BER=0/456): 01 02 03 00 05 06 07 08 09 0a 0b 0c 0d 0e 0f 10 11 12 13 14 15 16 17
-Testing CSD functions:
+Testing CSD functions (no FACCH):
 test_csd(TCH/F9.6): block #0 (pattern 0x00): n_errors=0 / n_bits_total=456
 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
@@ -477,4 +477,90 @@
 11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111
 11111111 11111111 11111111 11111111 11
+
+Testing CSD functions (with FACCH):
+test_csd(TCH/F9.6): block #0 (pattern 0x00): n_errors=34 / n_bits_total=456
+00000000 00000000 00000000 00000000 00010010 01100000 00000000 00000000
+00000000 00010011 01111000 00000000 00000000 00000000 00100100 10000000
+00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
+00000000 00000000 00000000 00000000 00000000 00000000
+test_csd(TCH/F9.6): block #1 (pattern 0xaa): n_errors=34 / n_bits_total=456
+01010101 01010101 01010101 01010101 01010101 01010101 01010101 01010101
+01010101 01010101 01010101 01010101 01010101 01010101 00101011 01010101
+01010101 01010101 01010101 01010101 01010101 01010101 01010101 01010101
+01010101 01010101 01010101 01010101 01010101 01010101
+test_csd(TCH/F9.6): block #2 (pattern 0xff): n_errors=6 / n_bits_total=456
+11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111
+11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111
+11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111
+11111111 11111111 11111111 11111111 11111111 11111111
+test_csd(TCH/F9.6): FACCH/F (pattern 0x2b): n_errors=0 / n_bits_total=0
+01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 
+
+test_csd(TCH/F4.8): block #0 (pattern 0x00): n_errors=38 / n_bits_total=456
+00000000 00000000 01010000 00000000 00000000 00000000 00000000 00000000
+00000000 00000000 00000000 00000000 00000000 00000000 00000000
+test_csd(TCH/F4.8): block #1 (pattern 0xaa): n_errors=37 / n_bits_total=456
+01010101 01010101 01010101 01010101 01010101 01010101 01010101 01010101
+01010101 01010101 01010101 01010101 01010101 01010101 01010101
+test_csd(TCH/F4.8): block #2 (pattern 0xff): n_errors=1 / n_bits_total=456
+11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111
+11111111 11111111 11111111 11111111 11111111 11111111 11111111
+test_csd(TCH/F4.8): FACCH/F (pattern 0x2b): n_errors=0 / n_bits_total=0
+01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 
+
+test_csd(TCH/H4.8): block #0 (pattern 0x00): n_errors=35 / n_bits_total=456
+00000000 00000000 00000000 00000000 00111000 10000000 00000000 00000000
+00000001 00000000 00000000 00000000 00000000 00000000 00011000 10000000
+00000000 00000000 00000000 00000000 00000000 00001000 00000000 00000000
+00000000 00000000 00000000 00000000 00000000 00000000
+test_csd(TCH/H4.8): block #1 (pattern 0xaa): n_errors=38 / n_bits_total=456
+01010101 01010101 01010101 01010101 01010101 01010101 01010101 01010101
+01010101 01010101 01010101 01010101 01010101 01010101 00101011 01010101
+01010101 01010101 01010101 00111010 01010101 01010101 01010101 01010101
+01010101 01010101 01010101 01010101 01010101 01010101
+test_csd(TCH/H4.8): block #2 (pattern 0xff): n_errors=1 / n_bits_total=456
+11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111
+11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111
+11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111
+11111111 11111111 11111111 11111111 11111111 11111111
+test_csd(TCH/H4.8): FACCH/H (pattern 0x2b): n_errors=2 / n_bits_total=456
+2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 
+
+test_csd(TCH/H2.4): block #0 (pattern 0x00): n_errors=38 / n_bits_total=456
+00000000 00000000 00000101 00000000 00000000 00000000 00000000 00000000
+00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
+00000000 00000000
+test_csd(TCH/H2.4): block #1 (pattern 0xaa): n_errors=32 / n_bits_total=456
+01010101 01010101 01010101 01010101 01010101 01010101 01010101 01010101
+01010101 01010101 01010101 01010101 01010101 01010101 01010101 01010101
+01010101 01010101
+test_csd(TCH/H2.4): block #2 (pattern 0xff): n_errors=0 / n_bits_total=456
+11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111
+11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111
+11111111 11111111
+test_csd(TCH/H2.4): FACCH/H (pattern 0x2b): n_errors=2 / n_bits_total=456
+2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 
+
+test_csd(TCH/F14.4): block #0 (pattern 0x00): n_errors=27 / n_bits_total=456
+00000000 00000000 00000000 00000000 00000000 00111100 01000000 00000000
+00000000 00000000 00000000 00111000 10011000 00000000 10000000 00000000
+00000000 00000000 00001111 10001101 01110000 00000000 00000000 00000000
+00000000 00000000 00001001 11000000 00000000 00000000 00000000 00000000
+00000000 00000010 00100010 01000000 00
+test_csd(TCH/F14.4): block #1 (pattern 0xaa): n_errors=35 / n_bits_total=456
+01010101 01010100 10110111 01010101 01010101 00011000 10010001 11000110
+11011100 11011101 11000110 01010101 01010101 01010101 10100100 10010001
+11000110 00001010 01010101 01010101 11101101 11010101 01010100 01010101
+01010101 01010101 00101001 00100101 01010101 01010101 01010101 01010101
+01010101 01010101 01010101 01010101 01
+test_csd(TCH/F14.4): block #2 (pattern 0xff): n_errors=3 / n_bits_total=456
+11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111
+11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111
+11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111
+11111111 11111111 11111111 11111111 11111111 11111111 11111111 11111111
+11111111 11111111 11111111 11111111 11
+test_csd(TCH/F14.4): FACCH/F (pattern 0x2b): n_errors=0 / n_bits_total=0
+01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 
+
 Success
-- 
To view, visit https://gerrit.osmocom.org/c/libosmocore/+/33004
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Gerrit-Project: libosmocore
Gerrit-Branch: master
Gerrit-Change-Id: Idc6decec3b84981d2aab4e27caab9ad65180f945
Gerrit-Change-Number: 33004
Gerrit-PatchSet: 2
Gerrit-Owner: fixeria vyanitskiy@sysmocom.de
Gerrit-Reviewer: Jenkins Builder
Gerrit-Reviewer: falconia falcon@freecalypso.org
Gerrit-Reviewer: fixeria vyanitskiy@sysmocom.de
Gerrit-Reviewer: laforge laforge@osmocom.org
Gerrit-Reviewer: pespin pespin@sysmocom.de
Gerrit-MessageType: merged



    

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[M] Change in libosmocore[master]: coding: test FACCH/[FH] bitstealing in test_csd()