LLVM 20.0.0git
Base64.h
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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
21namespace llvm {
22
23template <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
57llvm::Error decodeBase64(llvm::StringRef Input, std::vector<char> &Output);
58
59} // end namespace llvm
60
61#endif
Lightweight error class with error context and mandatory checking.
Definition: Error.h:160
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:50
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
std::string encodeBase64(InputBytes const &Bytes)
Definition: Base64.h:23
llvm::Error decodeBase64(llvm::StringRef Input, std::vector< char > &Output)
Definition: Base64.cpp:37