diff options
author | Holger Hans Peter Freyther <zecke@selfish.org> | 2011-06-23 17:53:27 -0400 |
---|---|---|
committer | Holger Hans Peter Freyther <zecke@selfish.org> | 2012-01-06 18:52:05 +0100 |
commit | faf1f64a2d0a54d37616a8bec8691346ab792cde (patch) | |
tree | cf9f5052348eae7207bceeb9803967686ca3e692 /openbsc/tests/gprs | |
parent | 26d0fe3c89042ed4008903dbe12c5110d8f9fc48 (diff) |
gprs: Honor GSM 04.64 8.4.2 Receipt of unacknowledged information
GSM 04.64 8.4.2 asks to ignore UI frames if the DLCI is not known,
or if the "(V(UR)- 32) <= N(U) < V(UR)". E.g. if we want to have
V(UR) == 511 and this frame is dropped, we would ignore N(U)'s
0 to 510. Calculate the delta.
The code is based on Jonathan Santos's "LLC UI window" fix but the
issue was discovered independly.
Diffstat (limited to 'openbsc/tests/gprs')
-rw-r--r-- | openbsc/tests/gprs/Makefile.am | 8 | ||||
-rw-r--r-- | openbsc/tests/gprs/gprs_test.c | 51 | ||||
-rw-r--r-- | openbsc/tests/gprs/gprs_test.ok | 16 |
3 files changed, 75 insertions, 0 deletions
diff --git a/openbsc/tests/gprs/Makefile.am b/openbsc/tests/gprs/Makefile.am new file mode 100644 index 000000000..e44125967 --- /dev/null +++ b/openbsc/tests/gprs/Makefile.am @@ -0,0 +1,8 @@ +INCLUDES = $(all_includes) -I$(top_srcdir)/include +AM_CFLAGS=-Wall -ggdb3 $(LIBOSMOCORE_CFLAGS) $(LIBOSMOGSM_CFLAGS) + +EXTRA_DIST = gprs_test.ok + +noinst_PROGRAMS = gprs_test + +gprs_test_SOURCES = gprs_test.c diff --git a/openbsc/tests/gprs/gprs_test.c b/openbsc/tests/gprs/gprs_test.c new file mode 100644 index 000000000..7b0e64113 --- /dev/null +++ b/openbsc/tests/gprs/gprs_test.c @@ -0,0 +1,51 @@ +#include <stdio.h> +#include <stdlib.h> +#include <inttypes.h> + +#include <openbsc/gprs_llc.h> + +#define ASSERT_FALSE(x) if (x) { printf("Should have returned false.\n"); abort(); } +#define ASSERT_TRUE(x) if (!x) { printf("Should have returned true.\n"); abort(); } + +/** + * GSM 04.64 8.4.2 Receipt of unacknowledged information + */ +static int nu_is_retransmission(uint16_t nu, uint16_t vur) +{ + int ret = gprs_llc_is_retransmit(nu, vur); + printf("N(U) = %d, V(UR) = %d => %s\n", nu, vur, + ret == 1 ? "retransmit" : "new"); + return ret; +} + +static void test_8_4_2() +{ + printf("Testing gprs_llc_is_retransmit.\n"); + + ASSERT_FALSE(nu_is_retransmission(0, 0)); + ASSERT_TRUE (nu_is_retransmission(0, 1)); + + /* expect 1... check for retransmissions */ + ASSERT_TRUE (nu_is_retransmission(0, 1)); + ASSERT_TRUE (nu_is_retransmission(511, 1)); + ASSERT_TRUE (nu_is_retransmission(483, 1)); + ASSERT_TRUE (nu_is_retransmission(482, 1)); + ASSERT_FALSE(nu_is_retransmission(481, 1)); + + /* expect 511... check for retransmissions */ + ASSERT_FALSE(nu_is_retransmission(0, 240)); // ahead + ASSERT_FALSE(nu_is_retransmission(0, 511)); // ahead + ASSERT_FALSE(nu_is_retransmission(1, 511)); // ahead + ASSERT_FALSE(nu_is_retransmission(511, 511)); // same + ASSERT_TRUE (nu_is_retransmission(510, 511)); // behind + ASSERT_TRUE (nu_is_retransmission(481, 511)); // behind + ASSERT_FALSE(nu_is_retransmission(479, 511)); // wrapped +} + +int main(int argc, char **argv) +{ + test_8_4_2(); + + printf("Done.\n"); + return EXIT_SUCCESS; +} diff --git a/openbsc/tests/gprs/gprs_test.ok b/openbsc/tests/gprs/gprs_test.ok new file mode 100644 index 000000000..39d37c120 --- /dev/null +++ b/openbsc/tests/gprs/gprs_test.ok @@ -0,0 +1,16 @@ +Testing gprs_llc_is_retransmit. +N(U) = 0, V(UR) = 0 => new +N(U) = 0, V(UR) = 1 => retransmit +N(U) = 0, V(UR) = 1 => retransmit +N(U) = 511, V(UR) = 1 => retransmit +N(U) = 483, V(UR) = 1 => retransmit +N(U) = 482, V(UR) = 1 => retransmit +N(U) = 481, V(UR) = 1 => new +N(U) = 0, V(UR) = 240 => new +N(U) = 0, V(UR) = 511 => new +N(U) = 1, V(UR) = 511 => new +N(U) = 511, V(UR) = 511 => new +N(U) = 510, V(UR) = 511 => retransmit +N(U) = 481, V(UR) = 511 => retransmit +N(U) = 479, V(UR) = 511 => new +Done. |