[base] bse64 encoder

Really slow implementation.  Speed up on a rainy day.

unit-tests/Makefile.in

@@ -47,6 +47,7 @@ TEST_SOURCE=\
 	\
 	unit-tests/array_block_t.cc \
 	unit-tests/array_t.cc \
+	unit-tests/base64_t.cc \
 	unit-tests/bitset_t.cc \
 	unit-tests/block_t.cc \
 	unit-tests/btree_t.cc \

unit-tests/base64_t.cc

@@ -0,0 +1,121 @@
+#include "gmock/gmock.h"
+#include "base/base64.h"
+
+#include <stdexcept>
+#include <stdlib.h>
+
+using namespace base;
+using namespace boost;
+using namespace std;
+using namespace testing;
+
+//----------------------------------------------------------------
+
+namespace {
+	typedef vector<unsigned char> bytes;
+
+	char const *wikipedia_examples[] = {
+		"any carnal pleasure.", "YW55IGNhcm5hbCBwbGVhc3VyZS4=",
+		"any carnal pleasure", "YW55IGNhcm5hbCBwbGVhc3VyZQ==",
+		"any carnal pleasur", "YW55IGNhcm5hbCBwbGVhc3Vy",
+		"any carnal pleasu", "YW55IGNhcm5hbCBwbGVhc3U=",
+		"any carnal pleas", "YW55IGNhcm5hbCBwbGVhcw==",
+		"pleasure.", "cGxlYXN1cmUu",
+		"leasure.", "bGVhc3VyZS4=",
+		"easure.", "ZWFzdXJlLg==",
+		"asure.", "YXN1cmUu",
+		"sure.", "c3VyZS4="
+	};
+
+	void assert_fails(decoded_or_error const &eoe, string const &msg) {
+		ASSERT_THAT(get<string>(eoe), Eq(msg));
+	}
+};
+
+//----------------------------------------------------------------
+
+TEST(Base64Tests, encoding_an_empty_string)
+{
+	bytes bs;
+	ASSERT_THAT(base64_encode(bs), Eq(string()));
+}
+
+TEST(Base64Tests, decoding_an_empty_string)
+{
+	bytes bs;
+	ASSERT_THAT(get<vector<unsigned char> >(base64_decode("")), Eq(bs));
+}
+
+TEST(Base64Tests, encode_single_byte)
+{
+	bytes bs(1);
+	bs[0] = 0;
+
+	ASSERT_THAT(base64_encode(bs), Eq(string("AA==")));
+}
+
+TEST(Base64Tests, encode_double_byte)
+{
+	bytes bs(2, 0);
+	ASSERT_THAT(base64_encode(bs), Eq(string("AAA=")));
+}
+
+TEST(Base64Tests, encode_triple_byte)
+{
+	bytes bs(3, 0);
+	ASSERT_THAT(base64_encode(bs), Eq(string("AAAA")));
+}
+
+TEST(Base64Tests, longer_encodings)
+{
+	for (unsigned example = 0; example < 5; example++) {
+		char const *in = wikipedia_examples[example * 2];
+		char const *out = wikipedia_examples[example * 2 + 1];
+		unsigned len = strlen(in);
+		bytes bs(len);
+		for (unsigned b = 0; b < len; b++)
+			bs.at(b) = in[b];
+
+		ASSERT_THAT(base64_encode(bs), Eq(string(out)));
+	}
+}
+
+TEST(Base64Tests, decoding_fails_with_bad_size_input)
+{
+	char const *err = "bad input length";
+
+	assert_fails(base64_decode("AAA"), err);
+	assert_fails(base64_decode("AA"), err);
+	assert_fails(base64_decode("A"), err);
+}
+
+TEST(Base64Tests, encode_decode_cycle)
+{
+	for (unsigned example = 0; example < 5; example++) {
+		char const *in = wikipedia_examples[example * 2];
+		unsigned len = strlen(in);
+		bytes bs(len);
+		for (unsigned b = 0; b < len; b++)
+			bs.at(b) = in[b];
+
+		decoded_or_error doe = base64_decode(base64_encode(bs));
+		ASSERT_THAT(get<vector<unsigned char> >(doe), Eq(bs));
+	}
+}
+
+TEST(Base64Tests, random_data)
+{
+	for (unsigned len = 1; len < 17; len++) {
+		for (unsigned example = 0; example < 10000; example++) {
+			vector<unsigned char> raw(len);
+
+			for (unsigned i = 0; i < len; i++)
+				raw.at(i) = ::rand() % 256;
+
+			decoded_or_error doe = base64_decode(base64_encode(raw));
+			ASSERT_THAT(get<vector<unsigned char> >(doe), Eq(raw));
+		}
+	}
+}
+
+//----------------------------------------------------------------