source/modules/juce_core/text/juce_Base64.cpp

   1 /*
   2   ==============================================================================
   3
   4    This file is part of the JUCE library.
   5    Copyright (c) 2022 - Raw Material Software Limited
   6
   7    JUCE is an open source library subject to commercial or open-source
   8    licensing.
   9
  10    The code included in this file is provided under the terms of the ISC license
  11    http://www.isc.org/downloads/software-support-policy/isc-license. Permission
  12    To use, copy, modify, and/or distribute this software for any purpose with or
  13    without fee is hereby granted provided that the above copyright notice and
  14    this permission notice appear in all copies.
  15
  16    JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
  17    EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
  18    DISCLAIMED.
  19
  20   ==============================================================================
  21 */
  22
  23 namespace juce
  24 {
  25
  26 bool Base64::convertToBase64 (OutputStream& base64Result, const void* sourceData, size_t sourceDataSize)
  27 {
  28     static const char lookup[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
  29     auto* source = static_cast<const uint8*> (sourceData);
  30
  31     while (sourceDataSize > 0)
  32     {
  33         char frame[4];
  34         auto byte0 = *source++;
  35         frame[0] = lookup [(byte0 & 0xfcu) >> 2];
  36         uint32 bits = (byte0 & 0x03u) << 4;
  37
  38         if (sourceDataSize > 1)
  39         {
  40             auto byte1 = *source++;
  41             frame[1] = lookup[bits | ((byte1 & 0xf0u) >> 4)];
  42             bits = (byte1 & 0x0fu) << 2;
  43
  44             if (sourceDataSize > 2)
  45             {
  46                 auto byte2 = *source++;
  47                 frame[2] = lookup[bits | ((byte2 & 0xc0u) >> 6)];
  48                 frame[3] = lookup[byte2 & 0x3fu];
  49                 sourceDataSize -= 3;
  50             }
  51             else
  52             {
  53                 frame[2] = lookup[bits];
  54                 frame[3] = '=';
  55                 sourceDataSize = 0;
  56             }
  57         }
  58         else
  59         {
  60             frame[1] = lookup[bits];
  61             frame[2] = '=';
  62             frame[3] = '=';
  63             sourceDataSize = 0;
  64         }
  65
  66         if (! base64Result.write (frame, 4))
  67             return false;
  68     }
  69
  70     return true;
  71 }
  72
  73 bool Base64::convertFromBase64 (OutputStream& binaryOutput, StringRef base64TextInput)
  74 {
  75     for (auto s = base64TextInput.text; ! s.isEmpty();)
  76     {
  77         uint8 data[4];
  78
  79         for (int i = 0; i < 4; ++i)
  80         {
  81             auto c = (uint32) s.getAndAdvance();
  82
  83             if (c >= 'A' && c <= 'Z')         c -= 'A';
  84             else if (c >= 'a' && c <= 'z')    c -= 'a' - 26;
  85             else if (c >= '0' && c <= '9')    c += 52 - '0';
  86             else if (c == '+')                c = 62;
  87             else if (c == '/')                c = 63;
  88             else if (c == '=')                { c = 64; if (i <= 1) return false; }
  89             else                              return false;
  90
  91             data[i] = (uint8) c;
  92         }
  93
  94         binaryOutput.writeByte ((char) ((data[0] << 2) | (data[1] >> 4)));
  95
  96         if (data[2] < 64)
  97         {
  98             binaryOutput.writeByte ((char) ((data[1] << 4) | (data[2] >> 2)));
  99
 100             if (data[3] < 64)
 101                 binaryOutput.writeByte ((char) ((data[2] << 6) | data[3]));
 102         }
 103     }
 104
 105     return true;
 106 }
 107
 108 String Base64::toBase64 (const void* sourceData, size_t sourceDataSize)
 109 {
 110     MemoryOutputStream m ((sourceDataSize * 4) / 3 + 3);
 111     bool ok = convertToBase64 (m, sourceData, sourceDataSize);
 112     jassertquiet (ok); // should always succeed for this simple case
 113     return m.toString();
 114 }
 115
 116 String Base64::toBase64 (const String& text)
 117 {
 118     return toBase64 (text.toRawUTF8(), strlen (text.toRawUTF8()));
 119 }
 120
 121
 122 //==============================================================================
 123 //==============================================================================
 124 #if JUCE_UNIT_TESTS
 125
 126 class Base64Tests  : public UnitTest
 127 {
 128 public:
 129     Base64Tests()
 130         : UnitTest ("Base64 class", UnitTestCategories::text)
 131     {}
 132
 133     static MemoryBlock createRandomData (Random& r)
 134     {
 135         MemoryOutputStream m;
 136
 137         for (int i = r.nextInt (400); --i >= 0;)
 138             m.writeByte ((char) r.nextInt (256));
 139
 140         return m.getMemoryBlock();
 141     }
 142
 143     void runTest() override
 144     {
 145         beginTest ("Base64");
 146
 147         auto r = getRandom();
 148
 149         for (int i = 1000; --i >= 0;)
 150         {
 151             auto original = createRandomData (r);
 152             auto asBase64 = Base64::toBase64 (original.getData(), original.getSize());
 153             MemoryOutputStream out;
 154             expect (Base64::convertFromBase64 (out, asBase64));
 155             auto result = out.getMemoryBlock();
 156             expect (result == original);
 157         }
 158     }
 159 };
 160
 161 static Base64Tests base64Tests;
 162
 163 #endif
 164
 165 } // namespace juce