#6567 Fixed memory leak causing zombie handles to created in the deamon on windows

Capture all process information as they are created to properly kill off handles when process are stopped, also added in a kill everything when the program cleans up all synergy(s|c) processes

src/lib/platform/MSWindowsWatchdog.cpp

@@ -37,6 +37,7 @@
 #include <UserEnv.h>
 #include <Shellapi.h>
 
+#define CURRENT_PROCESS_ID 0
 #define MAXIMUM_WAIT_TIME 3
 enum {
     kOutputBufferSize = 4096
@@ -338,6 +339,7 @@ MSWindowsWatchdog::startProcess()
         // wait for program to fail.
         ARCH->sleep(1);
         if (!isProcessActive()) {
+            closeProcessHandles(m_processInfo.dwProcessId);
             throw XMSWindowsWatchdogError("process immediately stopped");
         }
 
@@ -376,9 +378,13 @@ MSWindowsWatchdog::startProcessInForeground(String& command)
 	si.dwFlags |= STARTF_USESHOWWINDOW;
 	si.wShowWindow = SW_MINIMIZE;
 
-	return CreateProcess(
+	BOOL result =  CreateProcess(
 		NULL, LPSTR(command.c_str()), NULL, NULL,
 		TRUE, 0, NULL, NULL, &si, &m_processInfo);
+
+    m_children.insert(std::make_pair(m_processInfo.dwProcessId, m_processInfo));
+
+    return result;
 }
 
 BOOL
@@ -409,6 +415,8 @@ MSWindowsWatchdog::startProcessAsUser(String& command, HANDLE userToken, LPSECUR
         sa, NULL, TRUE, creationFlags,
         environment, NULL, &si, &m_processInfo);
 
+    m_children.insert(std::make_pair(m_processInfo.dwProcessId, m_processInfo));
+
     DestroyEnvironmentBlock(environment);
     CloseHandle(userToken);
 
@@ -529,13 +537,15 @@ MSWindowsWatchdog::shutdownProcess(HANDLE handle, DWORD pid, int timeout)
             ARCH->sleep(1);
         }
     }
+
+    closeProcessHandles(pid);
 }
 
 void
 MSWindowsWatchdog::shutdownExistingProcesses()
 {
     // first we need to take a snapshot of the running processes
-    HANDLE snapshot = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);
+    HANDLE snapshot = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, CURRENT_PROCESS_ID);
     if (snapshot == INVALID_HANDLE_VALUE) {
         LOG((CLOG_ERR "could not get process snapshot"));
         throw XArch(new XArchEvalWindows);
@@ -581,6 +591,7 @@ MSWindowsWatchdog::shutdownExistingProcesses()
         }
     }
 
+    clearAllChildren();
     CloseHandle(snapshot);
     m_processRunning = false;
 }
@@ -601,7 +612,7 @@ MSWindowsWatchdog::getActiveDesktop(LPSECURITY_ATTRIBUTES security)
         m_elevateProcess = elevateProcess;
 
         BOOL createRet = startProcessAsUser(syntoolCommand, userToken, security);
-
+        auto pid = m_processInfo.dwProcessId;
         if (!createRet) {
             DWORD rc = GetLastError();
             RevertToSelf();
@@ -622,6 +633,7 @@ MSWindowsWatchdog::getActiveDesktop(LPSECURITY_ATTRIBUTES security)
         }
         m_ready = false;
         ARCH->unlockMutex(m_mutex);
+        closeProcessHandles(pid);
     }
 } 
 
@@ -644,3 +656,22 @@ MSWindowsWatchdog::testOutput(String buffer)
         ARCH->unlockMutex(m_mutex);
     }
 }
+
+void MSWindowsWatchdog::closeProcessHandles(unsigned long pid, bool removeFromMap) {
+    auto processInfo = m_children.find(pid);
+    if (processInfo != m_children.end()) {
+        CloseHandle(processInfo->second.hProcess);
+        CloseHandle(processInfo->second.hThread);
+        if(removeFromMap) {
+            m_children.erase(processInfo);
+        }
+    }
+}
+
+void MSWindowsWatchdog::clearAllChildren() {
+    for (auto it = m_children.begin(); it != m_children.end(); ++it)
+    {
+        closeProcessHandles(it->second.dwThreadId, false);
+    }
+    m_children.clear();
+}

src/lib/platform/MSWindowsWatchdog.h

@@ -26,6 +26,7 @@
 #include <Windows.h>
 #include <string>
 #include <list>
+#include <map>
 
 class Thread;
 class IpcLogOutputter;
@@ -62,6 +63,17 @@ private:
     void                getActiveDesktop(LPSECURITY_ATTRIBUTES security);
     void                testOutput(String buffer);
 	void				setStartupInfo(STARTUPINFO& si);
+	void 				checkChildren();
+	/**
+	 * @brief This closes the handles held to a child thread
+	 * @param pid the ID of the process to kill, will do nothing if PID is not a valid child
+	 * @param removeFromMap should the function remove the item from the children map
+	 */
+	void                closeProcessHandles(unsigned long pid, bool removeFromMap = true);
+	/**
+	 * @brief This kills off all children's handles created by this process
+	 */
+	void 				clearAllChildren();
 
 private:
     Thread*             m_thread;
@@ -85,6 +97,11 @@ private:
     ArchCond            m_condVar;
     bool                m_ready;
 	bool				m_foreground;
+
+    /// @brief Save the info of all process made
+    ///         We will use this to track all processes we make and
+    ///         kill off handels and children that we no longer need
+	std::map<unsigned long, PROCESS_INFORMATION>   m_children;
 };
 
 //! Relauncher error