Simplify functions

src/base/preferences.cpp

@@ -548,10 +548,9 @@ QVector<Utils::Net::Subnet> Preferences::getWebUiAuthSubnetWhitelist() const
 
     for (const QString &rawSubnet : subnets)
     {
-        bool ok = false;
-        const Utils::Net::Subnet subnet = Utils::Net::parseSubnet(rawSubnet.trimmed(), &ok);
-        if (ok)
-            ret.append(subnet);
+        const std::optional<Utils::Net::Subnet> subnet = Utils::Net::parseSubnet(rawSubnet.trimmed());
+        if (subnet)
+            ret.append(subnet.value());
     }
 
     return ret;
@@ -561,9 +560,7 @@ void Preferences::setWebUiAuthSubnetWhitelist(QStringList subnets)
 {
     Algorithm::removeIf(subnets, [](const QString &subnet)
     {
-        bool ok = false;
-        Utils::Net::parseSubnet(subnet.trimmed(), &ok);
-        return !ok;
+        return !Utils::Net::parseSubnet(subnet.trimmed()).has_value();
     });
 
     setValue(u"Preferences/WebUI/AuthSubnetWhitelist"_qs, subnets);

src/base/utils/net.cpp

@@ -47,22 +47,15 @@ namespace Utils
             return !QHostAddress(ip).isNull();
         }
 
-        Subnet parseSubnet(const QString &subnetStr, bool *ok)
+        std::optional<Subnet> parseSubnet(const QString &subnetStr)
         {
-            const Subnet invalid = qMakePair(QHostAddress(), -1);
             const Subnet subnet = QHostAddress::parseSubnet(subnetStr);
-            if (ok)
-                *ok = (subnet != invalid);
+            const Subnet invalid = {QHostAddress(), -1};
+            if (subnet == invalid)
+                return std::nullopt;
             return subnet;
         }
 
-        bool canParseSubnet(const QString &subnetStr)
-        {
-            bool ok = false;
-            parseSubnet(subnetStr, &ok);
-            return ok;
-        }
-
         bool isLoopbackAddress(const QHostAddress &addr)
         {
             return (addr == QHostAddress::LocalHost)

src/base/utils/net.h

@@ -28,8 +28,10 @@
 
 #pragma once
 
-#include <QHostAddress>
+#include <optional>
+
 #include <QtContainerFwd>
+#include <QHostAddress>
 
 class QSslCertificate;
 class QSslKey;
@@ -37,11 +39,11 @@ class QString;
 
 namespace Utils::Net
 {
+    // alias for `QHostAddress::parseSubnet()` return type
     using Subnet = QPair<QHostAddress, int>;
 
     bool isValidIP(const QString &ip);
-    Subnet parseSubnet(const QString &subnetStr, bool *ok = nullptr);
-    bool canParseSubnet(const QString &subnetStr);
+    std::optional<Subnet> parseSubnet(const QString &subnetStr);
     bool isLoopbackAddress(const QHostAddress &addr);
     bool isIPInRange(const QHostAddress &addr, const QVector<Subnet> &subnets);
     QString subnetToString(const Subnet &subnet);