implemented attach functionality

GleeBug/Debugger.Loop.Exception.cpp

@@ -10,6 +10,10 @@ namespace GleeBug
             mProcess->systemBreakpoint = true;
             mContinueStatus = DBG_CONTINUE;
 
+            //call the attach callback if appropriate
+            if(mAttachedToProcess && mProcess->dwProcessId == mMainProcess.dwProcessId)
+                cbAttachBreakpoint();
+
             //call the callback
             cbSystemBreakpoint();
         }

GleeBug/Debugger.Loop.Process.cpp

@@ -4,6 +4,15 @@ namespace GleeBug
 {
     void Debugger::createProcessEvent(const CREATE_PROCESS_DEBUG_INFO & createProcess)
     {
+        //initial attach housekeeping
+        if(mAttachedToProcess && !mMainProcess.dwProcessId)
+        {
+            mMainProcess.hProcess = createProcess.hProcess;
+            mMainProcess.hThread = createProcess.hThread;
+            mMainProcess.dwProcessId = mDebugEvent.dwProcessId;
+            mMainProcess.dwThreadId = mDebugEvent.dwThreadId;
+        }
+
         //process housekeeping
         mProcesses.insert({ mDebugEvent.dwProcessId,
             Process(createProcess.hProcess,

GleeBug/Debugger.cpp

@@ -15,8 +15,8 @@ namespace GleeBug
         const wchar_t* szCommandLine,
         const wchar_t* szCurrentDirectory)
     {
-        STARTUPINFOW si;
+        memset(&mMainStartupInfo, 0, sizeof(mMainStartupInfo));
-        memset(&si, 0, sizeof(si));
+        memset(&mMainProcess, 0, sizeof(mMainProcess));
         const wchar_t* szFileNameCreateProcess;
         wchar_t* szCommandLineCreateProcess;
         wchar_t* szCreateWithCmdLine = nullptr;
@@ -42,14 +42,28 @@ namespace GleeBug
             DEBUG_PROCESS | CREATE_NEW_CONSOLE,
             nullptr,
             szCurrentDirectory,
-            &si,
+            &mMainStartupInfo,
             &mMainProcess);
 
         delete[] szCreateWithCmdLine;
+        mAttachedToProcess = false;
 
         return result;
     }
 
+    bool Debugger::Attach(DWORD processId)
+    {
+        //don't allow attaching when still debugging
+        if(mIsDebugging)
+            return false;
+        if(!DebugActiveProcess(processId))
+            return false;
+        mAttachedToProcess = true;
+        memset(&mMainStartupInfo, 0, sizeof(mMainStartupInfo));
+        memset(&mMainProcess, 0, sizeof(mMainProcess));
+        return true;
+    }
+
     bool Debugger::Stop() const
     {
         return !!TerminateProcess(mMainProcess.hProcess, 0);

GleeBug/Debugger.h

@@ -35,6 +35,13 @@ namespace GleeBug
             const wchar_t* szCommandLine,
             const wchar_t* szCurrentDirectory);
 
+        /**
+        \brief Attach to a debuggee.
+        \param processId Process to attach to.
+        \return true if the debuggee was attached to successfully, false otherwise.
+        */
+        bool Attach(DWORD processId);
+
         /**
         \brief Stops the debuggee (terminate the process)
         \return true if the debuggee was stopped correctly, false otherwise.
@@ -161,6 +168,11 @@ namespace GleeBug
         */
         virtual void cbUnhandledException(const EXCEPTION_RECORD & exceptionRecord, bool firstChance) {};
 
+        /**
+        \brief Attach breakpoint callback. Called just before cbSystemBreakpoint, only for the process that was attached to. Provide an implementation to use this callback.
+        */
+        virtual void cbAttachBreakpoint() {};
+
         /**
         \brief System breakpoint callback. Called after the event is internally processed. Provide an implementation to use this callback.
         */
@@ -260,6 +272,7 @@ namespace GleeBug
         virtual void exceptionHardwareBreakpoint(ptr exceptionAddress);
 
     protected: //variables
+        STARTUPINFOW mMainStartupInfo;
         PROCESS_INFORMATION mMainProcess;
         uint32 mContinueStatus = DBG_EXCEPTION_NOT_HANDLED;
         bool mBreakDebugger = false;
@@ -269,6 +282,7 @@ namespace GleeBug
         bool mIsDebugging = false;
         bool mDetach = false;
         bool mDetachAndBreak = false;
+        bool mAttachedToProcess = false;
         Capstone mCapstone;
 
         /**