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-rw-r--r--include/osmocom/core/bitvec.h10
-rw-r--r--src/bitvec.c75
-rw-r--r--tests/Makefile.am9
-rw-r--r--tests/bitvec/bitvec_test.c62
-rw-r--r--tests/bitvec/bitvec_test.ok2
-rw-r--r--tests/testsuite.at6
6 files changed, 162 insertions, 2 deletions
diff --git a/include/osmocom/core/bitvec.h b/include/osmocom/core/bitvec.h
index 62e2e7b6..89eb7848 100644
--- a/include/osmocom/core/bitvec.h
+++ b/include/osmocom/core/bitvec.h
@@ -28,6 +28,14 @@
/*! \file bitvec.h
* \brief Osmocom bit vector abstraction
+ *
+ * These functions assume a MSB (most significant bit) first layout of the
+ * bits, so that for instance the 5 bit number abcde (a is MSB) can be
+ * embedded into a byte sequence like in xxxxxxab cdexxxxx. The bit count
+ * starts with the MSB, so the bits in a byte are numbered (MSB) 01234567 (LSB).
+ * Note that there are other incompatible encodings, like it is used
+ * for the EGPRS RLC data block headers (there the bits are numbered from LSB
+ * to MSB).
*/
#include <stdint.h>
@@ -63,5 +71,7 @@ int bitvec_set_uint(struct bitvec *bv, unsigned int in, int count);
int bitvec_get_uint(struct bitvec *bv, int num_bits);
int bitvec_find_bit_pos(const struct bitvec *bv, unsigned int n, enum bit_value val);
int bitvec_spare_padding(struct bitvec *bv, unsigned int up_to_bit);
+int bitvec_get_bytes(struct bitvec *bv, uint8_t *bytes, int count);
+int bitvec_set_bytes(struct bitvec *bv, const uint8_t *bytes, int count);
/*! @} */
diff --git a/src/bitvec.c b/src/bitvec.c
index 8da5a480..726a7681 100644
--- a/src/bitvec.c
+++ b/src/bitvec.c
@@ -1,6 +1,7 @@
/* bit vector utility routines */
/* (C) 2009 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2015 by Sysmocom s.f.m.c. GmbH
*
* All Rights Reserved
*
@@ -30,6 +31,7 @@
#include <errno.h>
#include <stdint.h>
+#include <string.h>
#include <osmocom/core/bitvec.h>
@@ -261,4 +263,77 @@ int bitvec_find_bit_pos(const struct bitvec *bv, unsigned int n,
return -1;
}
+/*! \brief get multiple bytes from current pos
+ * Assumes MSB first encoding.
+ * \param[in] bv bit vector
+ * \param[in] bytes array
+ * \param[in] count number of bytes to copy
+ */
+int bitvec_get_bytes(struct bitvec *bv, uint8_t *bytes, int count)
+{
+ int byte_offs = bytenum_from_bitnum(bv->cur_bit);
+ int bit_offs = bv->cur_bit % 8;
+ uint8_t c, last_c;
+ int i;
+ uint8_t *src;
+
+ if (byte_offs + count + (bit_offs ? 1 : 0) > bv->data_len)
+ return -EINVAL;
+
+ if (bit_offs == 0) {
+ memcpy(bytes, bv->data + byte_offs, count);
+ } else {
+ src = bv->data + byte_offs;
+ last_c = *(src++);
+ for (i = count; i > 0; i--) {
+ c = *(src++);
+ *(bytes++) =
+ (last_c << bit_offs) |
+ (c >> (8 - bit_offs));
+ last_c = c;
+ }
+ }
+
+ bv->cur_bit += count * 8;
+ return 0;
+}
+
+/*! \brief set multiple bytes at current pos
+ * Assumes MSB first encoding.
+ * \param[in] bv bit vector
+ * \param[in] bytes array
+ * \param[in] count number of bytes to copy
+ */
+int bitvec_set_bytes(struct bitvec *bv, const uint8_t *bytes, int count)
+{
+ int byte_offs = bytenum_from_bitnum(bv->cur_bit);
+ int bit_offs = bv->cur_bit % 8;
+ uint8_t c, last_c;
+ int i;
+ uint8_t *dst;
+
+ if (byte_offs + count + (bit_offs ? 1 : 0) > bv->data_len)
+ return -EINVAL;
+
+ if (bit_offs == 0) {
+ memcpy(bv->data + byte_offs, bytes, count);
+ } else if (count > 0) {
+ dst = bv->data + byte_offs;
+ /* Get lower bits of first dst byte */
+ last_c = *dst >> (8 - bit_offs);
+ for (i = count; i > 0; i--) {
+ c = *(bytes++);
+ *(dst++) =
+ (last_c << (8 - bit_offs)) |
+ (c >> bit_offs);
+ last_c = c;
+ }
+ /* Overwrite lower bits of N+1 dst byte */
+ *dst = (*dst & ((1 << (8 - bit_offs)) - 1)) |
+ (last_c << (8 - bit_offs));
+ }
+
+ bv->cur_bit += count * 8;
+ return 0;
+}
/*! @} */
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 9d14350f..2411afa3 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -11,7 +11,8 @@ check_PROGRAMS = timer/timer_test sms/sms_test ussd/ussd_test \
logging/logging_test fr/fr_test \
loggingrb/loggingrb_test strrb/strrb_test \
vty/vty_test comp128/comp128_test utils/utils_test \
- smscb/gsm0341_test stats/stats_test
+ smscb/gsm0341_test stats/stats_test \
+ bitvec/bitvec_test
if ENABLE_MSGFILE
check_PROGRAMS += msgfile/msgfile_test
@@ -38,6 +39,9 @@ auth_milenage_test_LDADD = $(top_builddir)/src/libosmocore.la $(top_builddir)/sr
bits_bitrev_test_SOURCES = bits/bitrev_test.c
bits_bitrev_test_LDADD = $(top_builddir)/src/libosmocore.la
+bitvec_bitvec_test_SOURCES = bitvec/bitvec_test.c
+bitvec_bitvec_test_LDADD = $(top_builddir)/src/libosmocore.la
+
conv_conv_test_SOURCES = conv/conv_test.c
conv_conv_test_LDADD = $(top_builddir)/src/libosmocore.la
@@ -128,7 +132,8 @@ EXTRA_DIST = testsuite.at $(srcdir)/package.m4 $(TESTSUITE) \
fr/fr_test.ok loggingrb/logging_test.ok \
loggingrb/logging_test.err strrb/strrb_test.ok \
vty/vty_test.ok comp128/comp128_test.ok \
- utils/utils_test.ok stats/stats_test.ok
+ utils/utils_test.ok stats/stats_test.ok \
+ bitvec/bitvec_test.ok
DISTCLEANFILES = atconfig
diff --git a/tests/bitvec/bitvec_test.c b/tests/bitvec/bitvec_test.c
new file mode 100644
index 00000000..624e3346
--- /dev/null
+++ b/tests/bitvec/bitvec_test.c
@@ -0,0 +1,62 @@
+#include <inttypes.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+
+#include <osmocom/core/utils.h>
+#include <osmocom/core/bitvec.h>
+
+static void test_byte_ops()
+{
+ struct bitvec bv;
+ const uint8_t *in = (const uint8_t *)"ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+ uint8_t out[26 + 2];
+ uint8_t data[64];
+ int i;
+ int rc;
+ int in_size = strlen((const char *)in);
+
+ printf("=== start %s ===\n", __func__);
+
+ bv.data = data;
+ bv.data_len = sizeof(data);
+
+ for (i = 0; i < 32; i++) {
+ /* Write to bitvec */
+ memset(data, 0x00, sizeof(data));
+ bv.cur_bit = i;
+ rc = bitvec_set_uint(&bv, 0x7e, 8);
+ OSMO_ASSERT(rc >= 0);
+ rc = bitvec_set_bytes(&bv, in, in_size);
+ OSMO_ASSERT(rc >= 0);
+ rc = bitvec_set_uint(&bv, 0x7e, 8);
+ OSMO_ASSERT(rc >= 0);
+
+ fprintf(stderr, "bitvec: %s\n", osmo_hexdump(bv.data, bv.data_len));
+
+ /* Read from bitvec */
+ memset(out, 0xff, sizeof(out));
+ bv.cur_bit = i;
+ rc = bitvec_get_uint(&bv, 8);
+ OSMO_ASSERT(rc == 0x7e);
+ rc = bitvec_get_bytes(&bv, out + 1, in_size);
+ OSMO_ASSERT(rc >= 0);
+ rc = bitvec_get_uint(&bv, 8);
+ OSMO_ASSERT(rc == 0x7e);
+
+ fprintf(stderr, "out: %s\n", osmo_hexdump(out, sizeof(out)));
+
+ OSMO_ASSERT(out[0] == 0xff);
+ OSMO_ASSERT(out[in_size+1] == 0xff);
+ OSMO_ASSERT(memcmp(in, out + 1, in_size) == 0);
+ }
+
+ printf("=== end %s ===\n", __func__);
+}
+
+int main(int argc, char **argv)
+{
+ test_byte_ops();
+ return 0;
+}
diff --git a/tests/bitvec/bitvec_test.ok b/tests/bitvec/bitvec_test.ok
new file mode 100644
index 00000000..1f329aff
--- /dev/null
+++ b/tests/bitvec/bitvec_test.ok
@@ -0,0 +1,2 @@
+=== start test_byte_ops ===
+=== end test_byte_ops ===
diff --git a/tests/testsuite.at b/tests/testsuite.at
index 85c3e8bd..55e79f19 100644
--- a/tests/testsuite.at
+++ b/tests/testsuite.at
@@ -21,6 +21,12 @@ cat $abs_srcdir/bits/bitrev_test.ok > expout
AT_CHECK([$abs_top_builddir/tests/bits/bitrev_test], [0], [expout])
AT_CLEANUP
+AT_SETUP([bitvec])
+AT_KEYWORDS([bitvec])
+cat $abs_srcdir/bitvec/bitvec_test.ok > expout
+AT_CHECK([$abs_top_builddir/tests/bitvec/bitvec_test], [0], [expout], [ignore])
+AT_CLEANUP
+
AT_SETUP([conv])
AT_KEYWORDS([conv])
cat $abs_srcdir/conv/conv_test.ok > expout