base64: Add new module

Encodes and decodes base64. No linebreaks, always padding.

1 files changed, 70 insertions, 0 deletions

diff --git a/test/base64.cc b/test/base64.cc
new file mode 100644
index 0000000..47cdfa4
--- /dev/null
+++ b/test/base64.cc
@@ -0,0 +1,70 @@
+#include "base64.hh"
+
+#include <algorithm>
+#include <cstddef>
+#include <cstdint>
+#include <gtest/gtest.h>
+#include <iterator>
+#include <vector>
+
+TEST(Base64, empty) {
+  auto str = base64::encode({});
+  EXPECT_EQ("", str);
+
+  auto data = base64::decode("");
+  ASSERT_TRUE(data.has_value());
+  EXPECT_TRUE(data->empty());
+}
+
+TEST(Base64, all_bytes) {
+  std::vector<uint8_t> in;
+  in.push_back(0);
+  for (uint8_t i = 0; i < 255; ++i) {
+    in.push_back(i + 1);
+  }
+  auto str = base64::encode(in);
+  EXPECT_EQ(
+      "AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8gISIjJCUmJygpKissLS4vMDEyMzQ1"
+      "Njc4"
+      "OTo7PD0+"
+      "P0BBQkNERUZHSElKS0xNTk9QUVJTVFVWV1hZWltcXV5fYGFiY2RlZmdoaWprbG1ub3Bx"
+      "cnN0dXZ3eHl6e3x9fn+"
+      "AgYKDhIWGh4iJiouMjY6PkJGSk5SVlpeYmZqbnJ2en6ChoqOkpaanqKmq"
+      "q6ytrq+wsbKztLW2t7i5uru8vb6/wMHCw8TFxsfIycrLzM3Oz9DR0tPU1dbX2Nna29zd3t/"
+      "g4eLj"
+      "5OXm5+jp6uvs7e7v8PHy8/T19vf4+fr7/P3+/w==",
+      str);
+
+  auto data = base64::decode(str);
+  ASSERT_TRUE(data.has_value());
+  EXPECT_EQ(in, data.value());
+}
+
+TEST(Base64, rfc) {
+  std::string_view in = "foobar";
+  std::vector<std::string_view> expected{
+    "", "Zg==", "Zm8=", "Zm9v", "Zm9vYg==", "Zm9vYmE=", "Zm9vYmFy",
+  };
+  for (size_t i = 0; i <= in.size(); ++i) {
+    auto in_part = in.substr(0, i);
+    std::vector<uint8_t> in_bytes;
+    std::ranges::copy(in_part, std::back_inserter(in_bytes));
+    auto str = base64::encode(in_bytes);
+    EXPECT_EQ(expected[i], str);
+    auto data = base64::decode(str);
+    ASSERT_TRUE(data.has_value());
+    EXPECT_EQ(in_bytes, data.value());
+  }
+}
+
+TEST(Base64, invalid) {
+  std::vector<uint8_t> out;
+  EXPECT_FALSE(base64::decode("=", out));
+  EXPECT_FALSE(base64::decode("==", out));
+  EXPECT_FALSE(base64::decode("===", out));
+  EXPECT_FALSE(base64::decode("====", out));
+  EXPECT_FALSE(base64::decode("<>", out));
+  EXPECT_FALSE(base64::decode("Z", out));
+  EXPECT_FALSE(base64::decode("Zg", out));
+  EXPECT_FALSE(base64::decode("Zg=", out));
+}