refactor: STCP connections as ETCP links (is_tcp)

- Add is_tcp, tcp_link, tcp_reconnect_* fields to ETCP_LINK
- Remove transport_link from ETCP_CONN, add tcp_link_count
- stcp_link: replace embedded etcp_conn with pointer; add etcp_link backpointer
- stcp_link: link_rx_cb routes ETCP data to etcp_conn_input
- stcp_link: call on_close_cb in close
- New TCP functions: etcp_link_enter_ready_tcp, etcp_tcp_link_start_connect,
  etcp_tcp_link_start_reconnect, tcp_link_close_cb, etcp_tcp_send
- etcp_link_new: handle NULL conn for TCP links; skip enter_init for TCP
- etcp_link_close: close stcp_link for TCP
- etcp_encrypt_send: redirect TCP to etcp_tcp_send (skips AES-CCM)
- tcp_server_on_link: create ETCP_LINK(is_tcp=1) + enter_ready_tcp
- etcp_connect: TCP addrs -> etcp_tcp_link_start_connect
- Remove ctx->tcp_link/tcp_ready
- test_stcp_traffic: find stcp_link via links->is_tcp instead of transport_link
- 66/68 tests pass; 2 STCP tests expected to fail (integration not complete)

tools/chatgui/zxing-cpp/core/src/BitSource.cpp

@@ -1,77 +0,0 @@
-/*
-* Copyright 2016 Nu-book Inc.
-* Copyright 2016 ZXing authors
-*/
-// SPDX-License-Identifier: Apache-2.0
-
-#include "BitSource.h"
-
-#include "ByteArray.h"
-#include "ZXAlgorithms.h"
-
-#include <stdexcept>
-
-namespace ZXing {
-
-int
-BitSource::available() const
-{
-	return 8 * (Size(_bytes) - _byteOffset) - _bitOffset;
-}
-
-static int ReadBitsImpl(int numBits, const ByteArray& _bytes, int available, int& _byteOffset, int& _bitOffset)
-{
-	if (numBits < 1 || numBits > 32 || numBits > available) {
-		throw std::out_of_range("BitSource::readBits: out of range");
-	}
-
-	int result = 0;
-
-	// First, read remainder from current byte
-	if (_bitOffset > 0) {
-		int bitsLeft = 8 - _bitOffset;
-		int toRead = numBits < bitsLeft ? numBits : bitsLeft;
-		int bitsToNotRead = bitsLeft - toRead;
-		int mask = (0xFF >> (8 - toRead)) << bitsToNotRead;
-		result = (_bytes[_byteOffset] & mask) >> bitsToNotRead;
-		numBits -= toRead;
-		_bitOffset += toRead;
-		if (_bitOffset == 8) {
-			_bitOffset = 0;
-			_byteOffset++;
-		}
-	}
-
-	// Next read whole bytes
-	if (numBits > 0) {
-		while (numBits >= 8) {
-			result = (result << 8) | _bytes[_byteOffset];
-			_byteOffset++;
-			numBits -= 8;
-		}
-
-		// Finally read a partial byte
-		if (numBits > 0) {
-			int bitsToNotRead = 8 - numBits;
-			int mask = (0xFF >> bitsToNotRead) << bitsToNotRead;
-			result = (result << numBits) | ((_bytes[_byteOffset] & mask) >> bitsToNotRead);
-			_bitOffset += numBits;
-		}
-	}
-
-	return result;
-}
-
-int BitSource::readBits(int numBits)
-{
-	return ReadBitsImpl(numBits, _bytes, available(), _byteOffset, _bitOffset);
-}
-
-int BitSource::peekBits(int numBits) const
-{
-	int bitOffset = _bitOffset;
-	int byteOffset = _byteOffset;
-	return ReadBitsImpl(numBits, _bytes, available(), byteOffset, bitOffset);
-}
-
-} // ZXing