bitvec: Add get/set byte sequences

The new functions bitvec_get_bytes and bitvec_set_bytes copy
byte sequences from bitvecs to uint8_t arrays and vice versa.
While the bytes in the bitvecs do not need to be aligned, the uint8_t
arrays always are. In case the bytes in the bitvec are aligned, the
implementation uses memcpy.

Note that the implementation like the other existing functions assume
MSB first encoding.

[hfreyther: Squash the comment fix into this commit as well]

Sponsored-by: On-Waves ehf

2 files changed, 64 insertions, 0 deletions

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 ===