1 files changed, 56 insertions, 0 deletions
diff --git a/llvm/include/llvm/Support/Base64.h b/llvm/include/llvm/Support/Base64.h
new file mode 100644
index 000000000000..62064a35aa34
--- /dev/null
+++ b/llvm/include/llvm/Support/Base64.h
@@ -0,0 +1,56 @@
+//===--- Base64.h - Base64 Encoder/Decoder ----------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file provides generic base64 encoder/decoder.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_SUPPORT_BASE64_H
+#define LLVM_SUPPORT_BASE64_H
+
+#include <string>
+
+namespace llvm {
+
+template <class InputBytes> std::string encodeBase64(InputBytes const &Bytes) {
+  static const char Table[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+                              "abcdefghijklmnopqrstuvwxyz"
+                              "0123456789+/";
+  std::string Buffer;
+  Buffer.resize(((Bytes.size() + 2) / 3) * 4);
+
+  size_t i = 0, j = 0;
+  for (size_t n = Bytes.size() / 3 * 3; i < n; i += 3, j += 4) {
+    uint32_t x = ((unsigned char)Bytes[i] << 16) |
+                 ((unsigned char)Bytes[i + 1] << 8) |
+                 (unsigned char)Bytes[i + 2];
+    Buffer[j + 0] = Table[(x >> 18) & 63];
+    Buffer[j + 1] = Table[(x >> 12) & 63];
+    Buffer[j + 2] = Table[(x >> 6) & 63];
+    Buffer[j + 3] = Table[x & 63];
+  }
+  if (i + 1 == Bytes.size()) {
+    uint32_t x = ((unsigned char)Bytes[i] << 16);
+    Buffer[j + 0] = Table[(x >> 18) & 63];
+    Buffer[j + 1] = Table[(x >> 12) & 63];
+    Buffer[j + 2] = '=';
+    Buffer[j + 3] = '=';
+  } else if (i + 2 == Bytes.size()) {
+    uint32_t x =
+        ((unsigned char)Bytes[i] << 16) | ((unsigned char)Bytes[i + 1] << 8);
+    Buffer[j + 0] = Table[(x >> 18) & 63];
+    Buffer[j + 1] = Table[(x >> 12) & 63];
+    Buffer[j + 2] = Table[(x >> 6) & 63];
+    Buffer[j + 3] = '=';
+  }
+  return Buffer;
+}
+
+} // end namespace llvm
+
+#endif