SYNERGY-1017 - Add an option to stop the app which causes secure input

src/gui/src/MainWindow.cpp

@@ -333,13 +333,32 @@ void MainWindow::checkSystemInterruptions()
     if(synergyType() == synergyServer)
     {
 #if defined(Q_OS_MAC)
-        if(!m_isSecureInputNotificationShown && isOSXSecureInputEnabled())
+        if(!isOSXSecureInputEnabled())
         {
+            m_isSecureInputNotificationShown = false;
+        }
+        else if(!m_isSecureInputNotificationShown)
+        {
+            // avoid showing multiple duplicate messages
             m_isSecureInputNotificationShown = true;
+
             QMessageBox message(this);
             message.addButton(QObject::tr("Accept"), QMessageBox::AcceptRole);
-            message.setText(QObject::tr("Secure input was enabled in your system by another application. Synergy will not be able to send keyboard strokes while the secure input is enabled"));
-            message.exec();
+            std::string messageText =
+                    "Secure input was enabled in your system by another application. " \
+                    "Synergy will not be able to send keyboard strokes while the secure input is enabled\n\n";
+            int secureInputProcessPID = getOSXSecureInputEventPID();
+            std::string infringingProcessName = getOSXProcessName(secureInputProcessPID);
+
+            // IO registry may not contain the secure input process PID
+            // in this case don't add an option to quit the infringing app
+            if(secureInputProcessPID == 0) infringingProcessName = "unknown";
+            else message.addButton(QString("Quit %1").arg(infringingProcessName.c_str()), QMessageBox::ApplyRole);
+            messageText += "Infringing process is " + infringingProcessName;
+            message.setText(QObject::tr(messageText.c_str()));
+
+            // if user decides to stop the app send the SIGTERM signal
+            if (message.exec() == QMessageBox::Accepted && secureInputProcessPID) kill(secureInputProcessPID, SIGTERM);
         }
 #endif
     }

src/gui/src/OSXHelpers.h

@@ -19,7 +19,11 @@
 
 #define OSXHELPERS__H
 
+#include <string>
+
 bool isOSXSecureInputEnabled();
+int getOSXSecureInputEventPID();
+std::string getOSXProcessName(int pid);
 bool isOSXInterfaceStyleDark();
 bool isOSXUseDarkIcons();
 

src/gui/src/OSXHelpers.mm

@@ -20,7 +20,15 @@
 #import <Foundation/Foundation.h>
 #import <CoreData/CoreData.h>
 #import <Cocoa/Cocoa.h>
+#import <base/Log.h>
+
 #import <Carbon/Carbon.h>
+#import <mach/mach_port.h>
+#import <mach/mach_interface.h>
+#import <mach/mach_init.h>
+#import <IOKit/IOMessage.h>
+#import <IOKit/IOKitLib.h>
+#import <libproc.h>
 
 
 bool
@@ -29,6 +37,61 @@ isOSXSecureInputEnabled()
     return IsSecureEventInputEnabled();
 }
 
+int
+getOSXSecureInputEventPID()
+{
+    io_service_t		service = MACH_PORT_NULL, service_root = MACH_PORT_NULL;
+    mach_port_t			masterPort;
+
+    kern_return_t kr = IOMasterPort( MACH_PORT_NULL, &masterPort );
+    if(kr != KERN_SUCCESS) return 0;
+
+    // IO registry refuses to tap into the root level directly
+    // as a workaround access the parent of the top user level
+    service = IORegistryEntryFromPath( masterPort, kIOServicePlane ":/" );
+    IORegistryEntryGetParentEntry(service, kIOServicePlane, &service_root);
+
+    std::unique_ptr<std::remove_pointer<CFTypeRef>::type, decltype(&CFRelease)> consoleUsers(
+        IORegistryEntrySearchCFProperty(service_root, kIOServicePlane, CFSTR("IOConsoleUsers"), NULL, kIORegistryIterateParents | kIORegistryIterateRecursively),
+        CFRelease
+    );
+    if(!consoleUsers) return 0;
+
+    CFTypeID type = CFGetTypeID(consoleUsers.get());
+    if(type != CFArrayGetTypeID()) return 0;
+
+    CFTypeRef dict = CFArrayGetValueAtIndex((CFArrayRef)consoleUsers.get(), 0);
+    if(!dict) return 0;
+
+    type = CFGetTypeID(dict);
+    if(type != CFDictionaryGetTypeID()) return 0;
+
+    CFTypeRef secureInputPID = nullptr;
+    CFDictionaryGetValueIfPresent((CFDictionaryRef)dict, CFSTR("kCGSSessionSecureInputPID"), &secureInputPID);
+
+    if(secureInputPID == nullptr) return 0;
+
+    type = CFGetTypeID(secureInputPID);
+    if(type != CFNumberGetTypeID()) return 0;
+
+    auto pidRef = (CFNumberRef)secureInputPID;
+    CFNumberType numberType = CFNumberGetType(pidRef);
+    if(numberType != kCFNumberSInt32Type) return 0;
+
+    int pid;
+    CFNumberGetValue(pidRef, kCFNumberSInt32Type, &pid);
+    return pid;
+}
+
+std::string
+getOSXProcessName(int pid)
+{
+    if(!pid) return "";
+    char buf[128];
+    proc_name(pid, buf, sizeof(buf));
+    return buf;
+}
+
 bool
 isOSXInterfaceStyleDark()
 {