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 encodeBase64(InputBytes const & Bytes)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 57 llvm::Error decodeBase64(llvm::StringRef Input, std::vector<char> &Output); 58 59 } // end namespace llvm 60 61 #endif 62