Function dump_qr_code

kernel/kernel/Debug.cpp:151–256

	}

	void dump_qr_code()
	{
		ASSERT(Kernel::g_paniced);

		auto boot_framebuffer = Kernel::FramebufferDevice::boot_framebuffer();
		if (!boot_framebuffer)
		{
			derrorln("No boot framebuffer, not generating QR code");
			return;
		}
		if (boot_framebuffer->width() < 177 + 8 || boot_framebuffer->height() < 177 + 8)
		{
			derrorln("Boot framebuffer is too small for a qr code");
			return;
		}

		// rotate logs to start from index 0 and be contiguous
		rotate(s_debug_buffer, s_debug_buffer + s_debug_buffer_tail, s_debug_buffer + sizeof(s_debug_buffer));

		auto compressed_or_error = compress_kernel_logs();
		if (compressed_or_error.is_error())
		{
			// TODO: send uncompressed logs?
			derrorln("Failed to compress kernel logs: {}", compressed_or_error.error());
			return;
		}

		auto compressed = compressed_or_error.release_value();

		static uint8_t qr_code_data[s_qr_code_max_capacity];
		size_t qr_code_data_len = 0;

		for (size_t i = 0; s_panic_url_prefix[i]; i++)
			qr_code_data[qr_code_data_len++] = s_panic_url_prefix[i];

		constexpr char alphabet[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_";
		for (size_t i = 0; i < compressed.size() / 3; i++)
		{
			const uint32_t bits =
				((compressed[3 * i + 0]) << 16) |
				((compressed[3 * i + 1]) <<  8) |
				((compressed[3 * i + 2]) <<  0);

			qr_code_data[qr_code_data_len++] = alphabet[(bits >> 18) & 0x3F];
			qr_code_data[qr_code_data_len++] = alphabet[(bits >> 12) & 0x3F];
			qr_code_data[qr_code_data_len++] = alphabet[(bits >>  6) & 0x3F];
			qr_code_data[qr_code_data_len++] = alphabet[(bits >>  0) & 0x3F];
		}

		switch (compressed.size() % 3)
		{
			case 0:
				break;
			case 1:
			{
				const uint16_t bits =
					(compressed[compressed.size() - 1] << 4);
				qr_code_data[qr_code_data_len++] = alphabet[(bits >>  6) & 0x3F];