Advance Wayland and KDE package bring-up

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

local/recipes/kde/kf6-kcodecs/source/src/kcodecsbase64.cpp

@@ -0,0 +1,400 @@
+/*  -*- c++ -*-
+    SPDX-FileCopyrightText: 2001 Marc Mutz <mutz@kde.org>
+
+    SPDX-License-Identifier: LGPL-2.0-or-later
+*/
+/**
+  @file
+  This file is part of the API for handling @ref MIME data and
+  defines the @ref Base64 and @ref RFC2047B @ref Codec classes.
+
+  @brief
+  Defines the Base64Codec and Rfc2047BEncodingCodec classes.
+
+  @authors Marc Mutz \<mutz@kde.org\>
+*/
+
+#include "kcodecsbase64.h"
+#include "kcodecs_p.h"
+
+#include <QDebug>
+
+#include <cassert>
+
+using namespace KCodecs;
+
+namespace KCodecs
+{
+// codec for base64 as specified in RFC 2045
+// class Base64Codec;
+// class Base64Decoder;
+// class Base64Encoder;
+
+// codec for the B encoding as specified in RFC 2047
+// class Rfc2047BEncodingCodec;
+// class Rfc2047BEncodingEncoder;
+// class Rfc2047BEncodingDecoder;
+
+//@cond PRIVATE
+static const uchar base64DecodeMap[128] = {
+    64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
+
+    64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 62, 64, 64, 64, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 64, 64, 64, 64, 64, 64,
+
+    64, 0,  1,  2,  3,  4,  5,  6,  7,  8,  9,  10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 64, 64, 64, 64, 64,
+
+    64, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 64, 64, 64, 64, 64};
+
+static const char base64EncodeMap[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', '+', '/'};
+//@endcond
+
+class Base64Decoder : public Decoder
+{
+    uint mStepNo;
+    uchar mOutbits;
+    bool mSawPadding : 1;
+
+protected:
+    friend class Base64Codec;
+    Base64Decoder(Codec::NewlineType newline = Codec::NewlineLF)
+        : Decoder(newline)
+        , mStepNo(0)
+        , mOutbits(0)
+        , mSawPadding(false)
+    {
+    }
+
+public:
+    ~Base64Decoder() override
+    {
+    }
+
+    bool decode(const char *&scursor, const char *const send, char *&dcursor, const char *const dend) override;
+    // ### really needs no finishing???
+    bool finish(char *&dcursor, const char *const dend) override
+    {
+        Q_UNUSED(dcursor);
+        Q_UNUSED(dend);
+        return true;
+    }
+};
+
+class Base64Encoder : public Encoder
+{
+    uint mStepNo;
+    /** number of already written base64-quartets on current line */
+    uint mWrittenPacketsOnThisLine;
+    uchar mNextbits;
+    bool mInsideFinishing : 1;
+
+protected:
+    friend class Rfc2047BEncodingCodec;
+    friend class Rfc2047BEncodingEncoder;
+    friend class Base64Codec;
+    Base64Encoder(Codec::NewlineType newline = Codec::NewlineLF)
+        : Encoder(newline)
+        , mStepNo(0)
+        , mWrittenPacketsOnThisLine(0)
+        , mNextbits(0)
+        , mInsideFinishing(false)
+    {
+    }
+
+    bool generic_finish(char *&dcursor, const char *const dend, bool withLFatEnd);
+
+public:
+    ~Base64Encoder() override
+    {
+    }
+
+    bool encode(const char *&scursor, const char *const send, char *&dcursor, const char *const dend) override;
+
+    bool finish(char *&dcursor, const char *const dend) override;
+
+protected:
+    bool writeBase64(uchar ch, char *&dcursor, const char *const dend)
+    {
+        return write(base64EncodeMap[ch], dcursor, dend);
+    }
+};
+
+class Rfc2047BEncodingEncoder : public Base64Encoder
+{
+protected:
+    friend class Rfc2047BEncodingCodec;
+    Rfc2047BEncodingEncoder(Codec::NewlineType newline = Codec::NewlineLF)
+        : Base64Encoder(newline)
+    {
+    }
+
+public:
+    bool encode(const char *&scursor, const char *const send, char *&dcursor, const char *const dend) override;
+    bool finish(char *&dcursor, const char *const dend) override;
+};
+
+Encoder *Base64Codec::makeEncoder(Codec::NewlineType newline) const
+{
+    return new Base64Encoder(newline);
+}
+
+Decoder *Base64Codec::makeDecoder(Codec::NewlineType newline) const
+{
+    return new Base64Decoder(newline);
+}
+
+Encoder *Rfc2047BEncodingCodec::makeEncoder(Codec::NewlineType newline) const
+{
+    return new Rfc2047BEncodingEncoder(newline);
+}
+
+/********************************************************/
+/********************************************************/
+/********************************************************/
+
+bool Base64Decoder::decode(const char *&scursor, const char *const send, char *&dcursor, const char *const dend)
+{
+    while (dcursor != dend && scursor != send) {
+        uchar ch = *scursor++;
+        uchar value;
+
+        // try converting ch to a 6-bit value:
+        if (ch < 128) {
+            value = base64DecodeMap[ch];
+        } else {
+            value = 64;
+        }
+
+        // ch isn't of the base64 alphabet, check for other significant chars:
+        if (value >= 64) {
+            if (ch == '=') {
+                // padding:
+                if (mStepNo == 0 || mStepNo == 1) {
+                    if (!mSawPadding) {
+                        // malformed
+                        // qWarning() << "Base64Decoder: unexpected padding"
+                        //              "character in input stream";
+                    }
+                    mSawPadding = true;
+                    break;
+                } else if (mStepNo == 2) {
+                    // ok, there should be another one
+                } else if (mStepNo == 3) {
+                    // ok, end of encoded stream
+                    mSawPadding = true;
+                    break;
+                }
+                mSawPadding = true;
+                mStepNo = (mStepNo + 1) % 4;
+                continue;
+            } else {
+                // non-base64 alphabet
+                continue;
+            }
+        }
+
+        if (mSawPadding) {
+            // qWarning() << "Base64Decoder: Embedded padding character"
+            //              "encountered!";
+            return true;
+        }
+
+        // add the new bits to the output stream and flush full octets:
+        switch (mStepNo) {
+        case 0:
+            mOutbits = value << 2;
+            break;
+        case 1:
+            *dcursor++ = (char)(mOutbits | value >> 4);
+            mOutbits = value << 4;
+            break;
+        case 2:
+            *dcursor++ = (char)(mOutbits | value >> 2);
+            mOutbits = value << 6;
+            break;
+        case 3:
+            *dcursor++ = (char)(mOutbits | value);
+            mOutbits = 0;
+            break;
+        default:
+            assert(0);
+        }
+        mStepNo = (mStepNo + 1) % 4;
+    }
+
+    // return false when caller should call us again:
+    return scursor == send;
+} // Base64Decoder::decode()
+
+bool Base64Encoder::encode(const char *&scursor, const char *const send, char *&dcursor, const char *const dend)
+{
+    const uint maxPacketsPerLine = 76 / 4;
+
+    // detect when the caller doesn't adhere to our rules:
+    if (mInsideFinishing) {
+        return true;
+    }
+
+    while (scursor != send && dcursor != dend) {
+        // properly empty the output buffer before starting something new:
+        // ### fixme: we can optimize this away, since the buffer isn't
+        // written to anyway (most of the time)
+        if (d->outputBufferCursor && !flushOutputBuffer(dcursor, dend)) {
+            return scursor == send;
+        }
+
+        uchar ch = *scursor++;
+        // mNextbits   // (part of) value of next sextet
+
+        // check for line length;
+        if (mStepNo == 0 && mWrittenPacketsOnThisLine >= maxPacketsPerLine) {
+            writeCRLF(dcursor, dend);
+            mWrittenPacketsOnThisLine = 0;
+        }
+
+        // depending on mStepNo, extract value and mNextbits from the
+        // octet stream:
+        switch (mStepNo) {
+        case 0:
+            assert(mNextbits == 0);
+            writeBase64(ch >> 2, dcursor, dend); // top-most 6 bits -> output
+            mNextbits = (ch & 0x3) << 4; // 0..1 bits -> 4..5 in mNextbits
+            break;
+        case 1:
+            assert((mNextbits & ~0x30) == 0);
+            writeBase64(mNextbits | ch >> 4, dcursor, dend); // 4..7 bits -> 0..3 in value
+            mNextbits = (ch & 0xf) << 2; // 0..3 bits -> 2..5 in mNextbits
+            break;
+        case 2:
+            assert((mNextbits & ~0x3C) == 0);
+            writeBase64(mNextbits | ch >> 6, dcursor, dend); // 6..7 bits -> 0..1 in value
+            writeBase64(ch & 0x3F, dcursor, dend); // 0..5 bits -> output
+            mNextbits = 0;
+            mWrittenPacketsOnThisLine++;
+            break;
+        default:
+            assert(0);
+        }
+        mStepNo = (mStepNo + 1) % 3;
+    }
+
+    if (d->outputBufferCursor) {
+        flushOutputBuffer(dcursor, dend);
+    }
+
+    return scursor == send;
+}
+
+bool Rfc2047BEncodingEncoder::encode(const char *&scursor, const char *const send, char *&dcursor, const char *const dend)
+{
+    // detect when the caller doesn't adhere to our rules:
+    if (mInsideFinishing) {
+        return true;
+    }
+
+    while (scursor != send && dcursor != dend) {
+        // properly empty the output buffer before starting something new:
+        // ### fixme: we can optimize this away, since the buffer isn't
+        // written to anyway (most of the time)
+        if (d->outputBufferCursor && !flushOutputBuffer(dcursor, dend)) {
+            return scursor == send;
+        }
+
+        uchar ch = *scursor++;
+        // mNextbits   // (part of) value of next sextet
+
+        // depending on mStepNo, extract value and mNextbits from the
+        // octet stream:
+        switch (mStepNo) {
+        case 0:
+            assert(mNextbits == 0);
+            writeBase64(ch >> 2, dcursor, dend); // top-most 6 bits -> output
+            mNextbits = (ch & 0x3) << 4; // 0..1 bits -> 4..5 in mNextbits
+            break;
+        case 1:
+            assert((mNextbits & ~0x30) == 0);
+            writeBase64(mNextbits | ch >> 4, dcursor, dend); // 4..7 bits -> 0..3 in value
+            mNextbits = (ch & 0xf) << 2; // 0..3 bits -> 2..5 in mNextbits
+            break;
+        case 2:
+            assert((mNextbits & ~0x3C) == 0);
+            writeBase64(mNextbits | ch >> 6, dcursor, dend); // 6..7 bits -> 0..1 in value
+            writeBase64(ch & 0x3F, dcursor, dend); // 0..5 bits -> output
+            mNextbits = 0;
+            break;
+        default:
+            assert(0);
+        }
+        mStepNo = (mStepNo + 1) % 3;
+    }
+
+    if (d->outputBufferCursor) {
+        flushOutputBuffer(dcursor, dend);
+    }
+
+    return scursor == send;
+}
+
+bool Base64Encoder::finish(char *&dcursor, const char *const dend)
+{
+    return generic_finish(dcursor, dend, true);
+}
+
+bool Rfc2047BEncodingEncoder::finish(char *&dcursor, const char *const dend)
+{
+    return generic_finish(dcursor, dend, false);
+}
+
+bool Base64Encoder::generic_finish(char *&dcursor, const char *const dend, bool withLFatEnd)
+{
+    if (mInsideFinishing) {
+        return flushOutputBuffer(dcursor, dend);
+    }
+
+    if (d->outputBufferCursor && !flushOutputBuffer(dcursor, dend)) {
+        return false;
+    }
+
+    mInsideFinishing = true;
+
+    //
+    // writing out the last mNextbits...
+    //
+    switch (mStepNo) {
+    case 1: // 2 mNextbits waiting to be written. Needs two padding chars:
+    case 2: // 4 or 6 mNextbits waiting to be written. Completes a block
+        writeBase64(mNextbits, dcursor, dend);
+        mNextbits = 0;
+        break;
+    case 0: // no padding, nothing to be written, except possibly the CRLF
+        assert(mNextbits == 0);
+        break;
+    default:
+        assert(0);
+    }
+
+    //
+    // adding padding...
+    //
+    switch (mStepNo) {
+    case 1:
+        write('=', dcursor, dend);
+        Q_FALLTHROUGH();
+    // fall through:
+    case 2:
+        write('=', dcursor, dend);
+        Q_FALLTHROUGH();
+    // fall through:
+    case 0: // completed a quartet - add CRLF
+        if (withLFatEnd) {
+            writeCRLF(dcursor, dend);
+        }
+        return flushOutputBuffer(dcursor, dend);
+    default:
+        assert(0);
+    }
+    return true; // asserts get compiled out
+}
+
+} // namespace KCodecs