1 files changed, 85 insertions, 0 deletions
diff --git a/tests/bitgen/bitgen_test.c b/tests/bitgen/bitgen_test.c
new file mode 100644
index 00000000..bd472916
--- /dev/null
+++ b/tests/bitgen/bitgen_test.c
@@ -0,0 +1,85 @@
+#include <inttypes.h>
+#include <osmocom/core/bit16gen.h>
+#include <osmocom/core/bit32gen.h>
+#include <osmocom/core/bit64gen.h>
+
+#define DO_TEST(BE_LE, SIZE) do { \
+		int8_t len; \
+		printf("--- " #SIZE " " #BE_LE "\n"); \
+		for (len = SIZE / 8; len > 0; len--) { \
+			uint8_t buf[len * 2]; \
+			uint8_t at_idx; \
+			uint##SIZE##_t val = (uint##SIZE##_t)0x8877665544332211; \
+			\
+			for (at_idx = 0; at_idx < len; at_idx++) { \
+				uint##SIZE##_t read_val = 0; \
+				memset(buf, 0, sizeof(buf)); \
+				osmo_store##SIZE##BE_LE##_ext(val, &buf[at_idx], len); \
+				printf("osmo_store" #SIZE #BE_LE "_ext(0x%" PRIx##SIZE ", &buf[%d], %d) = %s\n", \
+				       val, \
+				       at_idx, len, osmo_hexdump(buf, sizeof(buf))); \
+				\
+				read_val = osmo_load##SIZE##BE_LE##_ext(&buf[at_idx], len); \
+				printf("osmo_load" #SIZE #BE_LE "_ext(&buf[%d], %d) = 0x%" PRIx##SIZE "\n", \
+				       at_idx, len, read_val); \
+				\
+				if (!strcmp(#BE_LE, "be")) { \
+					read_val = osmo_load##SIZE##BE_LE##_ext_2(&buf[at_idx], len); \
+					printf("osmo_load" #SIZE #BE_LE "_ext_2(&buf[%d], %d) = 0x%" PRIx##SIZE "\n", \
+					       at_idx, len, read_val); \
+				} \
+			} \
+		} \
+	} while (0)
+
+/* Shims to allow compiling, the *le_ext_2 are not actually invoked because of the strcmp() condition above. */
+#define osmo_load16le_ext_2 dummy
+#define osmo_load32le_ext_2 dummy
+#define osmo_load64le_ext_2 dummy
+
+static inline uint64_t dummy(const void *p, uint8_t n)
+{
+	OSMO_ASSERT(false);
+}
+
+int main(int argc, char **argv)
+{
+	DO_TEST(be, 16);
+	DO_TEST(le, 16);
+	DO_TEST(be, 32);
+	DO_TEST(le, 32);
+	DO_TEST(be, 64);
+	DO_TEST(le, 64);
+
+	{
+		printf("--- store/load 0x112233 as 24bit big-endian, legacy\n");
+		uint8_t buf[4];
+		memset(buf, 0, sizeof(buf));
+		osmo_store32be_ext(0x00112233, buf, 3); // stores 11 22 33
+		printf("%s\n", osmo_hexdump(buf, 4));
+		uint32_t r = osmo_load32be_ext(buf, 3); // returns 0x11223300, not 0x00112233
+		printf("0x%x\n", r);
+	}
+
+	{
+		printf("--- store/load 0x112233 as 24bit big-endian\n");
+		uint8_t buf[4];
+		memset(buf, 0, sizeof(buf));
+		osmo_store32be_ext(0x00112233, buf, 3); // stores 11 22 33
+		printf("%s\n", osmo_hexdump(buf, 4));
+		uint32_t r = osmo_load32be_ext_2(buf, 3); // returns 0x00112233
+		printf("0x%x\n", r);
+	}
+
+	{
+		printf("--- store/load 0x112233 as 24bit little-endian\n");
+		uint8_t buf[4];
+		memset(buf, 0, sizeof(buf));
+		osmo_store32le_ext(0x00112233, buf, 3); // stores 33 22 11
+		printf("%s\n", osmo_hexdump(buf, 4));
+		uint32_t r = osmo_load32le_ext(buf, 3); // returns 0x00112233
+		printf("0x%x\n", r);
+	}
+
+	return 0;
+}