GetComPortList.cpp

/*
Copyright © 2022 Nicholas J. Kinar
Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation
files (the “Software”), to deal in the Software without
restriction, including without limitation the rights to use,
copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following
conditions:
The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.
*/

#include <iostream>
#include <string>
#include <cstdint>
#include <algorithm>
#if defined (_WIN32) || defined( _WIN64)
#include <windows.h>
#endif
#if defined (__linux__)
#include <filesystem>
#endif
#if defined(__APPLE__)
#include <stdio.h>
#include <regex>
#include <filesystem>
#endif
#include "GetComPortList.h"


/*
A simple class to enumerate COM ports on Windows, Linux and Mac OS X
REFERENCES:
https://stackoverflow.com/questions/2674048/what-is-proper-way-to-detect-all-available-serial-ports-on-windows
https://stackoverflow.com/questions/15342804/c-linux-detect-all-serial-ports
https://stackoverflow.com/questions/52164723/how-to-execute-a-command-and-get-return-code-stdout-and-stderr-of-command-in-c
https://stackoverflow.com/questions/3815211/mac-command-line-list-available-serial-ports
*/


GetComPortList::GetComPortList()
= default;


std::vector<std::string> GetComPortList::get_list_serial_ports()
{
	std::vector<std::string> port_list;
#if defined (_WIN32) || defined( _WIN64)
	const uint32_t CHAR_NUM = 1024;
	const uint32_t MAX_PORTS = 255;
	const std::string COM_STR = "COM";
	char path[CHAR_NUM];
	for (uint32_t k = 0; k < MAX_PORTS; k++)
	{
		std::string port_name = COM_STR + std::to_string(k);
		DWORD test = QueryDosDevice(port_name.c_str(), path, CHAR_NUM);
		if (test == 0) continue;
		port_list.push_back(port_name);
	}
#endif
#if defined (__linux__)
	namespace fs = std::filesystem;
    const std::string DEV_PATH = "/dev/serial/by-id";
    try
    {
        fs::path p(DEV_PATH);
        if (!fs::exists(DEV_PATH)) return port_list;
        for (fs::directory_entry de: fs::directory_iterator(p))
        {
            if (fs::is_symlink(de.symlink_status()))
            {
                fs::path symlink_points_at = fs::read_symlink(de);
                port_list.push_back(std::string("/dev/")+symlink_points_at.filename().c_str());
            }
        }
    }
    catch (const fs::filesystem_error &ex) {}
#endif
#if defined(__APPLE__)
	namespace fs = std::filesystem;
	const std::string DEV_PATH = "/dev";
	const std::regex base_regex(R"(\/dev\/(tty|cu)\..*)");
    try
    {
        fs::path p(DEV_PATH);
        if (!fs::exists(DEV_PATH)) return port_list;
        for (fs::directory_entry de: fs::directory_iterator(p)) {
            fs::path canonical_path = fs::canonical(de);
            std::string name = canonical_path.generic_string();
            std::smatch res;
            std::regex_search(name, res, base_regex);
            if (res.empty()) continue;
            port_list.push_back(canonical_path.generic_string());
        }
    }
    catch (const fs::filesystem_error &ex) {}
#endif
	std::sort(port_list.begin(), port_list.end());
	return port_list;
}// end


void GetComPortList::print_serial_port_list()
{
	std::vector<std::string> lst = get_list_serial_ports();
	for (const std::string& s: lst)
	{
		std::cout << s << std::endl;
	}
} //  end