Add simple config file support to XSwiftBus

This adds a simple configuration file to XSwiftbus. So far, only the
xswiftbus DBus server is configured.

ref T291

src/xswiftbus/config.cpp

@@ -0,0 +1,138 @@
+/* Copyright (C) 2018
+ * swift Project Community / Contributors
+ *
+ * This file is part of swift project. It is subject to the license terms in the LICENSE file found in the top-level
+ * directory of this distribution and at http://www.swift-project.org/license.html. No part of swift project,
+ * including this file, may be copied, modified, propagated, or distributed except according to the terms
+ * contained in the LICENSE file.
+ */
+
+#include "config.h"
+#include "utils.h"
+#include <fstream>
+#include <string>
+#include <cctype>
+#include <algorithm>
+
+namespace XSwiftBus
+{
+
+    //! Case insensitive string compare
+    bool stringCompare(const std::string & str1, const std::string &str2)
+    {
+        if (str1.size() != str2.size()) { return false; }
+        return std::equal(str1.begin(), str1.end(), str2.begin(), [](const char & c1, const char & c2)
+        {
+            return (c1 == c2 || std::toupper(c1) == std::toupper(c2));
+        });
+    }
+
+    CConfig::CConfig()
+    {}
+
+    CConfig::~CConfig() {}
+
+    void CConfig::parse()
+    {
+        std::ifstream configFile(m_filePath);
+        if (! configFile.is_open()) { return; }
+
+        std::string line;
+        int lineNo = 1;
+
+        while (std::getline(configFile, line))
+        {
+            line.erase(std::remove_if(line.begin(), line.end(), isspace), line.end());
+            if (line.empty() || line[0] == '#') { continue; }
+
+            auto delimiterPos = line.find("=");
+            if (delimiterPos == std::string::npos)
+            {
+                WARNING_LOG("xswiftbus.conf line " + std::to_string(lineNo) + ": Skipping invalid line!");
+                lineNo++;
+                continue;
+            }
+
+            std::string key = line.substr(0, delimiterPos);
+            std::string value = line.substr(delimiterPos + 1);
+
+            if (key.empty() || value.empty())
+            {
+                WARNING_LOG("xswiftbus.conf line " + std::to_string(lineNo) + ": Skipping invalid line!");
+                lineNo++;
+                continue;
+            }
+
+            bool valid = true;
+            if (stringCompare(key, "dbusMode")) { valid = parseDBusMode(value); }
+            else if (stringCompare(key, "dbusAddress")) { valid = parseDBusAddress(value); }
+            else if (stringCompare(key, "dbusPort")) { valid = parseDBusPort(value); }
+            else
+            {
+                WARNING_LOG("xswiftbus.conf line " + std::to_string(lineNo) + ": Unknown variable " + value + "!");
+                lineNo++;
+                continue;
+            }
+
+            if (! valid)
+            {
+                WARNING_LOG("xswiftbus.conf line " + std::to_string(lineNo) + ": Skipping invalid line!");
+                lineNo++;
+                continue;
+            }
+
+            lineNo++;
+        }
+    }
+
+    void CConfig::print()
+    {
+        DEBUG_LOG("XSwiftBus configuration:");
+        DEBUG_LOG("DBus mode: " + dbusModeToString(m_dbusMode));
+        DEBUG_LOG("DBus server address: " + m_dbusAddress);
+        DEBUG_LOG("DBus server port: " + std::to_string(m_dbusPort));
+    }
+
+    bool CConfig::parseDBusMode(const std::string &value)
+    {
+        if (stringCompare(value, "session")) { m_dbusMode = CConfig::DBusSession; return true; }
+        else if (stringCompare(value, "P2P")) { m_dbusMode = CConfig::DBusP2P; return true; }
+        else { return false; }
+    }
+
+    bool CConfig::parseDBusAddress(const std::string &value)
+    {
+
+        m_dbusAddress = value;
+        return true;
+    }
+
+    bool CConfig::parseDBusPort(const std::string &value)
+    {
+        int port = 0;
+        try
+        {
+            port = std::stoi(value);
+        }
+        catch (...)
+        {
+            return false;
+        }
+
+        if (port < 0 || port > 65535) { return false; }
+        m_dbusPort = port;
+        return true;
+    }
+
+    std::string CConfig::dbusModeToString(DBusMode mode)
+    {
+        switch (mode)
+        {
+        case DBusSession: return "Session";
+        case DBusP2P: return "P2P";
+        }
+
+        return {};
+    }
+
+} // ns