Prepare wpiutil for merge into allwpilib.

wpiutil/src/main/native/include/support/Base64.h

@@ -0,0 +1,40 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) 2015-2018 FIRST. All Rights Reserved.                        */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#ifndef WPIUTIL_SUPPORT_BASE64_H_
+#define WPIUTIL_SUPPORT_BASE64_H_
+
+#include <cstddef>
+#include <string>
+
+#include "llvm/StringRef.h"
+
+namespace llvm {
+template <typename T>
+class SmallVectorImpl;
+class raw_ostream;
+}  // namespace llvm
+
+namespace wpi {
+
+size_t Base64Decode(llvm::raw_ostream& os, llvm::StringRef encoded);
+
+size_t Base64Decode(llvm::StringRef encoded, std::string* plain);
+
+llvm::StringRef Base64Decode(llvm::StringRef encoded, size_t* num_read,
+                             llvm::SmallVectorImpl<char>& buf);
+
+void Base64Encode(llvm::raw_ostream& os, llvm::StringRef plain);
+
+void Base64Encode(llvm::StringRef plain, std::string* encoded);
+
+llvm::StringRef Base64Encode(llvm::StringRef plain,
+                             llvm::SmallVectorImpl<char>& buf);
+
+}  // namespace wpi
+
+#endif  // WPIUTIL_SUPPORT_BASE64_H_