Reimplement WaitFor.

1 files changed, 27 insertions, 25 deletions

diff --git a/c/main.cpp b/c/main.cpp
index 97b71b9..d6e3027 100644
--- a/c/main.cpp
+++ b/c/main.cpp
@@ -1,5 +1,6 @@
 #include <exception>
 #include <stdexcept>
+#include <thread>
 #include <windows.h>
 #include <commctrl.h>
 #include <SWI-Prolog.h>
@@ -71,8 +72,8 @@ static void InitializeMainWindow(HWND);
 static LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
 /* Process main menu commands. */
 static void HandleMainMenu(HWND, WORD);
-/* Call Prolog predicate in other thread, if available. */
-static void WaitFor(const char*, const char*);
+/* Wait for thread. */
+void WaitFor(void (*f)(bool*));
 /* Handle messages to Help > About dialog. */
 static INT_PTR CALLBACK AboutDlgProc(HWND, UINT, WPARAM, LPARAM);
 /* Try to style application according to current Windows theme. */
@@ -400,11 +401,13 @@ void HandleMainMenu(const HWND hWnd, const WORD command)
 		break;
 
 	case IDM_FILE_FETCH_DATA:
-		WaitFor("episode_data","update_episode_data");
+	    {
+		WaitFor(FetchData);
 		break;
+	    }
 
 	case IDM_FILE_FETCH_SCREENWRITERS:
-		WaitFor("episode_data","update_screenwriters");
+		//WaitFor("episode_data","update_screenwriters");
 		break;
 
 	case IDM_FILE_ABOUT:
@@ -451,26 +454,24 @@ void HandleMainMenu(const HWND hWnd, const WORD command)
 	}
 }
 
-void WaitFor(const char* mod, const char* pred)
+void WaitFor(void (*f)(bool*))
 {
 	/* WaitFor uses a thread on the Prolog side to execute a
 	 * predicate asynchronously. */
 
-	static WcharPtr predActive;
+	static bool bActive = false;
+	static bool bDone = false;
 	static UINT_PTR iTimer;
-	static atom_t aThread;
 
-	if (predActive) {
-		wchar_t msg[256] = {0};
-		Swprintf(msg,
-		    L"Another task (%s) is active. "
+	if (bActive) {
+		if (EBMessageBox(L"Another task is active. "
 		    L"Do you want to cancel the existing task and start a new one?",
-		    static_cast<wchar_t*>(predActive));
-		if (EBMessageBox(msg, L"Error", MB_YESNO|MB_ICONWARNING) != IDYES)
+		    L"Error", MB_YESNO|MB_ICONWARNING) == IDYES) {
+			KillTimer(nullptr, iTimer);
+			bActive = false;
+			g_elv->Update();
+		} else
 			return;
-		KillTimer(nullptr, iTimer);
-		predActive = nullptr;
-		g_elv->Update();
 	}
 
 	/* The timer procedure animates an ellipsis in the status bar
@@ -481,22 +482,23 @@ void WaitFor(const char* mod, const char* pred)
 		static int i = 0;
 		static const wchar_t* text[] = {L".", L"..", L"...", L""};
 
-		if (Pl("episode_data","thread_running",aThread)) {
-			i = (i+1)%(sizeof(text)/sizeof(*text));
-			SendMessage(g_hWndStatus, SB_SETTEXT, MAKEWPARAM(1,0),
-			    reinterpret_cast<LPARAM>(text[i]));
-		} else {
+		if (bDone) {
 			KillTimer(nullptr, iTimer);
 			i = 0;
-			predActive = nullptr;
+			bActive = 0;
 			g_elv->Update();
+		} else {
+			i = (i+1)%(sizeof(text)/sizeof(*text));
+			SendMessage(g_hWndStatus, SB_SETTEXT, MAKEWPARAM(1,0),
+			    reinterpret_cast<LPARAM>(text[i]));
 		}
 	};
 
-	Plx(mod,"thread_create",pred,&aThread);
+	bDone = false;
+	bActive = true;
+	std::thread{f, &bDone}.detach();
 	SendMessage(g_hWndStatus, SB_SETTEXT, MAKEWPARAM(1,0), reinterpret_cast<LPARAM>(L"."));
-	if (Prefer(iTimer = SetTimer(nullptr, -1, 500, proc)))
-		predActive = WcharPtr::FromNarrow(pred);
+	Prefer(iTimer = SetTimer(nullptr, -1, 500, proc));
 }
 
 INT_PTR CALLBACK AboutDlgProc(const HWND hWnd, const UINT uMsg, const WPARAM wParam, const LPARAM)