aboutsummaryrefslogtreecommitdiff
path: root/src/zencore/base64.cpp
diff options
context:
space:
mode:
authorStefan Boberg <[email protected]>2023-05-02 10:01:47 +0200
committerGitHub <[email protected]>2023-05-02 10:01:47 +0200
commit075d17f8ada47e990fe94606c3d21df409223465 (patch)
treee50549b766a2f3c354798a54ff73404217b4c9af /src/zencore/base64.cpp
parentfix: bundle shouldn't append content zip to zen (diff)
downloadzen-075d17f8ada47e990fe94606c3d21df409223465.tar.xz
zen-075d17f8ada47e990fe94606c3d21df409223465.zip
moved source directories into `/src` (#264)
* moved source directories into `/src` * updated bundle.lua for new `src` path * moved some docs, icon * removed old test trees
Diffstat (limited to 'src/zencore/base64.cpp')
-rw-r--r--src/zencore/base64.cpp107
1 files changed, 107 insertions, 0 deletions
diff --git a/src/zencore/base64.cpp b/src/zencore/base64.cpp
new file mode 100644
index 000000000..b97dfebbf
--- /dev/null
+++ b/src/zencore/base64.cpp
@@ -0,0 +1,107 @@
+// Copyright Epic Games, Inc. All Rights Reserved.
+
+#include <zencore/base64.h>
+
+namespace zen {
+
+/** The table used to encode a 6 bit value as an ascii character */
+static const uint8_t EncodingAlphabet[64] = {'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
+ 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
+ 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
+ 'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/'};
+
+/** The table used to convert an ascii character into a 6 bit value */
+#if 0
+static const uint8_t DecodingAlphabet[256] = {
+ 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 0x00-0x0f
+ 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 0x10-0x1f
+ 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x3E, 0xFF, 0xFF, 0xFF, 0x3F, // 0x20-0x2f
+ 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x3B, 0x3C, 0x3D, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 0x30-0x3f
+ 0xFF, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, // 0x40-0x4f
+ 0x0F, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 0x50-0x5f
+ 0xFF, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, // 0x60-0x6f
+ 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F, 0x30, 0x31, 0x32, 0x33, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 0x70-0x7f
+ 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 0x80-0x8f
+ 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 0x90-0x9f
+ 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 0xa0-0xaf
+ 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 0xb0-0xbf
+ 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 0xc0-0xcf
+ 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 0xd0-0xdf
+ 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // 0xe0-0xef
+ 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF // 0xf0-0xff
+};
+#endif // 0
+
+template<typename CharType>
+uint32_t
+Base64::Encode(const uint8_t* Source, uint32_t Length, CharType* Dest)
+{
+ CharType* EncodedBytes = Dest;
+
+ // Loop through the buffer converting 3 bytes of binary data at a time
+ while (Length >= 3)
+ {
+ uint8_t A = *Source++;
+ uint8_t B = *Source++;
+ uint8_t C = *Source++;
+ Length -= 3;
+
+ // The algorithm takes 24 bits of data (3 bytes) and breaks it into 4 6bit chunks represented as ascii
+ uint32_t ByteTriplet = A << 16 | B << 8 | C;
+
+ // Use the 6bit block to find the representation ascii character for it
+ EncodedBytes[3] = EncodingAlphabet[ByteTriplet & 0x3F];
+ ByteTriplet >>= 6;
+ EncodedBytes[2] = EncodingAlphabet[ByteTriplet & 0x3F];
+ ByteTriplet >>= 6;
+ EncodedBytes[1] = EncodingAlphabet[ByteTriplet & 0x3F];
+ ByteTriplet >>= 6;
+ EncodedBytes[0] = EncodingAlphabet[ByteTriplet & 0x3F];
+
+ // Now we can append this buffer to our destination string
+ EncodedBytes += 4;
+ }
+
+ // Since this algorithm operates on blocks, we may need to pad the last chunks
+ if (Length > 0)
+ {
+ uint8_t A = *Source++;
+ uint8_t B = 0;
+ uint8_t C = 0;
+ // Grab the second character if it is a 2 uint8_t finish
+ if (Length == 2)
+ {
+ B = *Source;
+ }
+ uint32_t ByteTriplet = A << 16 | B << 8 | C;
+ // Pad with = to make a 4 uint8_t chunk
+ EncodedBytes[3] = '=';
+ ByteTriplet >>= 6;
+ // If there's only one 1 uint8_t left in the source, then you need 2 pad chars
+ if (Length == 1)
+ {
+ EncodedBytes[2] = '=';
+ }
+ else
+ {
+ EncodedBytes[2] = EncodingAlphabet[ByteTriplet & 0x3F];
+ }
+ // Now encode the remaining bits the same way
+ ByteTriplet >>= 6;
+ EncodedBytes[1] = EncodingAlphabet[ByteTriplet & 0x3F];
+ ByteTriplet >>= 6;
+ EncodedBytes[0] = EncodingAlphabet[ByteTriplet & 0x3F];
+
+ EncodedBytes += 4;
+ }
+
+ // Add a null terminator
+ *EncodedBytes = 0;
+
+ return uint32_t(EncodedBytes - Dest);
+}
+
+template ZENCORE_API uint32_t Base64::Encode<char>(const uint8_t* Source, uint32_t Length, char* Dest);
+template ZENCORE_API uint32_t Base64::Encode<wchar_t>(const uint8_t* Source, uint32_t Length, wchar_t* Dest);
+
+} // namespace zen