text: // Copyright 2015 The Chromium Authors. All rights reserved.
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  
  #ifndef BASE_BASE64URL_H_
  #define BASE_BASE64URL_H_
  
  #include <string>
  
  #include "base/base_export.h"
  #include "base/compiler_specific.h"
  #include "base/macros.h"
  #include "base/strings/string_piece.h"
  
  namespace base {
  
  enum class Base64UrlEncodePolicy {
    // Include the trailing padding in the output, when necessary.
    INCLUDE_PADDING,
  
    // Remove the trailing padding from the output.
    OMIT_PADDING
  };
  
  // Encodes the |input| string in base64url, defined in RFC 4648:
  // https://tools.ietf.org/html/rfc4648#section-5
  //
  // The |policy| defines whether padding should be included or omitted from the
  // encoded |*output|. |input| and |*output| may reference the same storage.
  BASE_EXPORT void Base64UrlEncode(const StringPiece& input,
                                   Base64UrlEncodePolicy policy,
                                   std::string* output);
  
  enum class Base64UrlDecodePolicy {
    // Require inputs contain trailing padding if non-aligned.
    REQUIRE_PADDING,
  
    // Accept inputs regardless of whether or not they have the correct padding.
    IGNORE_PADDING,
  
    // Reject inputs if they contain any trailing padding.
    DISALLOW_PADDING
  };
  
  // Decodes the |input| string in base64url, defined in RFC 4648:
  // https://tools.ietf.org/html/rfc4648#section-5
  //
  // The |policy| defines whether padding will be required, ignored or disallowed
  // altogether. |input| and |*output| may reference the same storage.
  BASE_EXPORT bool Base64UrlDecode(const StringPiece& input,
                                   Base64UrlDecodePolicy policy,
                                   std::string* output) WARN_UNUSED_RESULT;
  
  }  // namespace base
  
  #endif  // BASE_BASE64URL_H_
  