varint: Add varint encoding/decoding

This code is ported from git.git

Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: David Turner <dturner@twopensource.com>

1 files changed, 39 insertions, 0 deletions

diff --git a/tests/core/encoding.c b/tests/core/encoding.c
new file mode 100644
index 000000000..7d91720f4
--- /dev/null
+++ b/tests/core/encoding.c
@@ -0,0 +1,39 @@
+#include "clar_libgit2.h"
+#include "varint.h"
+
+void test_core_encoding__decode(void)
+{
+	const unsigned char *buf = (unsigned char *)"AB";
+	size_t size;
+
+	cl_assert(git_decode_varint(buf, &size) == 65);
+	cl_assert(size == 1);
+
+	buf = (unsigned char *)"\xfe\xdc\xbaXY";
+	cl_assert(git_decode_varint(buf, &size) == 267869656);
+	cl_assert(size == 4);
+
+	buf = (unsigned char *)"\xaa\xaa\xfe\xdc\xbaXY";
+	cl_assert(git_decode_varint(buf, &size) == 1489279344088ULL);
+	cl_assert(size == 6);
+
+	buf = (unsigned char *)"\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xfe\xdc\xbaXY";
+	cl_assert(git_decode_varint(buf, &size) == 0);
+	cl_assert(size == 0);
+
+}
+
+void test_core_encoding__encode(void)
+{
+	unsigned char buf[100];
+	cl_assert(git_encode_varint(buf, 100, 65) == 1);
+	cl_assert(buf[0] == 'A');
+
+	cl_assert(git_encode_varint(buf, 100, 267869656) == 4);
+	cl_assert(!memcmp(buf, "\xfe\xdc\xbaX", 4));
+
+	cl_assert(git_encode_varint(buf, 100, 1489279344088ULL) == 6);
+	cl_assert(!memcmp(buf, "\xaa\xaa\xfe\xdc\xbaX", 6));
+
+	cl_assert(git_encode_varint(buf, 1, 1489279344088ULL) == -1);
+}