1 | //===--- Base64.h - Base64 Encoder/Decoder ----------------------*- C++ -*-===// |
2 | // |
3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
4 | // See https://llvm.org/LICENSE.txt for license information. |
5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
6 | // |
7 | //===----------------------------------------------------------------------===// |
8 | // |
9 | // This file provides generic base64 encoder/decoder. |
10 | // |
11 | //===----------------------------------------------------------------------===// |
12 | |
13 | #ifndef LLVM_SUPPORT_BASE64_H |
14 | #define LLVM_SUPPORT_BASE64_H |
15 | |
16 | #include "llvm/Support/Error.h" |
17 | #include <cstdint> |
18 | #include <string> |
19 | #include <vector> |
20 | |
21 | namespace llvm { |
22 | |
23 | template <class InputBytes> std::string encodeBase64(InputBytes const &Bytes) { |
24 | static const char Table[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ" |
25 | "abcdefghijklmnopqrstuvwxyz" |
26 | "0123456789+/" ; |
27 | std::string Buffer; |
28 | Buffer.resize(((Bytes.size() + 2) / 3) * 4); |
29 | |
30 | size_t i = 0, j = 0; |
31 | for (size_t n = Bytes.size() / 3 * 3; i < n; i += 3, j += 4) { |
32 | uint32_t x = ((unsigned char)Bytes[i] << 16) | |
33 | ((unsigned char)Bytes[i + 1] << 8) | |
34 | (unsigned char)Bytes[i + 2]; |
35 | Buffer[j + 0] = Table[(x >> 18) & 63]; |
36 | Buffer[j + 1] = Table[(x >> 12) & 63]; |
37 | Buffer[j + 2] = Table[(x >> 6) & 63]; |
38 | Buffer[j + 3] = Table[x & 63]; |
39 | } |
40 | if (i + 1 == Bytes.size()) { |
41 | uint32_t x = ((unsigned char)Bytes[i] << 16); |
42 | Buffer[j + 0] = Table[(x >> 18) & 63]; |
43 | Buffer[j + 1] = Table[(x >> 12) & 63]; |
44 | Buffer[j + 2] = '='; |
45 | Buffer[j + 3] = '='; |
46 | } else if (i + 2 == Bytes.size()) { |
47 | uint32_t x = |
48 | ((unsigned char)Bytes[i] << 16) | ((unsigned char)Bytes[i + 1] << 8); |
49 | Buffer[j + 0] = Table[(x >> 18) & 63]; |
50 | Buffer[j + 1] = Table[(x >> 12) & 63]; |
51 | Buffer[j + 2] = Table[(x >> 6) & 63]; |
52 | Buffer[j + 3] = '='; |
53 | } |
54 | return Buffer; |
55 | } |
56 | |
57 | llvm::Error decodeBase64(llvm::StringRef Input, std::vector<char> &Output); |
58 | |
59 | } // end namespace llvm |
60 | |
61 | #endif |
62 | |