xref: /aosp_15_r20/external/cronet/base/base64.h (revision 6777b5387eb2ff775bb5750e3f5d96f37fb7352b)
1 // Copyright 2011 The Chromium Authors
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #ifndef BASE_BASE64_H_
6 #define BASE_BASE64_H_
7 
8 #include <stdint.h>
9 
10 #include <optional>
11 #include <string>
12 #include <vector>
13 
14 #include "base/base_export.h"
15 #include "base/containers/span.h"
16 #include "base/strings/string_piece.h"
17 
18 namespace base {
19 
20 // Encodes the input binary data in base64.
21 BASE_EXPORT std::string Base64Encode(span<const uint8_t> input);
22 
23 // Encodes the input binary data in base64 and appends it to the output.
24 BASE_EXPORT void Base64EncodeAppend(span<const uint8_t> input,
25                                     std::string* output);
26 
27 // Encodes the input string in base64.
28 BASE_EXPORT std::string Base64Encode(StringPiece input);
29 
30 // Decodes the base64 input string.  Returns true if successful and false
31 // otherwise. The output string is only modified if successful. The decoding can
32 // be done in-place.
33 enum class Base64DecodePolicy {
34   // Input should match the output format of Base64Encode. i.e.
35   // - Input length should be divisible by 4
36   // - Maximum of 2 padding characters
37   // - No non-base64 characters.
38   kStrict,
39 
40   // Matches https://infra.spec.whatwg.org/#forgiving-base64-decode.
41   // - Removes all ascii whitespace
42   // - Maximum of 2 padding characters
43   // - Allows input length not divisible by 4 if no padding chars are added.
44   kForgiving,
45 };
46 BASE_EXPORT bool Base64Decode(
47     StringPiece input,
48     std::string* output,
49     Base64DecodePolicy policy = Base64DecodePolicy::kStrict);
50 
51 // Decodes the base64 input string. Returns `std::nullopt` if unsuccessful.
52 BASE_EXPORT std::optional<std::vector<uint8_t>> Base64Decode(StringPiece input);
53 
54 }  // namespace base
55 
56 #endif  // BASE_BASE64_H_
57