Query abort via command bar button or Ctrl+C during execute using sqlite_progress_handler and a progress callback message pump that keeps the UI active during execution

Author: nfinit

src/sqlite-ce-edit/execute.c

@@ -4,6 +4,26 @@
 
 #include "globals.h"
 
+/*============================================================================
+** Progress callback for query abort
+**============================================================================*/
+
+static int ProgressCallback(void *arg) {
+    MSG msg;
+    (void)arg;
+    /* Process pending messages to keep UI responsive */
+    while (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) {
+        /* Check for Ctrl+C to abort */
+        if (msg.message == WM_KEYDOWN && msg.wParam == 'C' &&
+            GetKeyState(VK_CONTROL) < 0) {
+            g_abortQuery = 1;
+        }
+        TranslateMessage(&msg);
+        DispatchMessage(&msg);
+    }
+    return g_abortQuery;
+}
+
 /*============================================================================
 ** Query Execution State
 **============================================================================*/
@@ -163,9 +183,11 @@ void ExecuteQuery(void) {
         return;
     }
 
-    /* Disable Execute while running */
+    /* Disable Execute while running, enable Stop */
     EnableMenuItem(g_hMenu, IDM_EXECUTE, MF_GRAYED);
     SendMessage(g_hwndCB, TB_ENABLEBUTTON, IDM_EXECUTE, FALSE);
+    SendMessage(g_hwndCB, TB_ENABLEBUTTON, IDM_STOP, TRUE);
+    g_abortQuery = 0;
     UpdateWindow(g_hwndCB);
 
     /* Check for selection */
@@ -286,6 +308,9 @@ void ExecuteQuery(void) {
     g_nCols = 0;
     g_totalRows = 0;
 
+    /* Install progress handler for abort support */
+    sqlite_progress_handler(g_db, 1000, ProgressCallback, NULL);
+    
     SetStatusResult(L"Executing...");
     SendMessageW(g_hwndStatus, SB_SETTEXTW, 1, (LPARAM)L"Executing...");
     UpdateWindow(g_hwndStatus);
@@ -317,7 +342,11 @@ void ExecuteQuery(void) {
                 p[1] = '\0';
                 rc = sqlite_exec(g_db, stmt, QueryCallback, NULL, &errmsg);
                 p[1] = saved;
-                if (rc != SQLITE_OK) {
+                if (rc == SQLITE_INTERRUPT) {
+                    OutputLine("Query aborted by user.");
+                    if (errmsg) sqlite_freemem(errmsg);
+                    hadError = 1;
+                } else if (rc != SQLITE_OK) {
                     int ln = 1, i;
                     char lb[16]; char *lp = lb + 14;
                     const char *es = errmsg ? errmsg : sqlite_error_string(rc);
@@ -353,7 +382,11 @@ void ExecuteQuery(void) {
     /* Execute any remaining statement (no trailing semicolon) */
     if (!hadError && *stmt) {
         rc = sqlite_exec(g_db, stmt, QueryCallback, NULL, &errmsg);
-        if (rc != SQLITE_OK) {
+        if (rc == SQLITE_INTERRUPT) {
+            OutputLine("Query aborted by user.");
+            if (errmsg) sqlite_freemem(errmsg);
+            hadError = 1;
+        } else if (rc != SQLITE_OK) {
             int ln = 1, i;
             char lb[16]; char *lp = lb + 14;
             const char *es = errmsg ? errmsg : sqlite_error_string(rc);
@@ -382,7 +415,11 @@ void ExecuteQuery(void) {
 
     elapsed = GetTickCount() - startTick;
 
-    if (hadError) {
+    if (g_abortQuery) {
+        /* Query was aborted by user */
+        SendMessageW(g_hwndStatus, SB_SETTEXTW, 1, (LPARAM)L"Aborted");
+        SetStatusResult(L"Aborted");
+    } else if (hadError) {
         /* Position cursor at the errored statement */
         int adjOffset = errorOffset;
         int lineNum = 1;
@@ -419,9 +456,11 @@ void ExecuteQuery(void) {
     FlushOutput();
     UpdateDbSize();
 
-    /* Re-enable Execute */
+    /* Remove progress handler and re-enable Execute, disable Stop */
+    sqlite_progress_handler(g_db, 0, NULL, NULL);
     EnableMenuItem(g_hMenu, IDM_EXECUTE, MF_ENABLED);
     SendMessage(g_hwndCB, TB_ENABLEBUTTON, IDM_EXECUTE, TRUE);
+    SendMessage(g_hwndCB, TB_ENABLEBUTTON, IDM_STOP, FALSE);
 
     /* Switch to results view (unless error - stay in query to show cursor) */
     if (!hadError) {

src/sqlite-ce-edit/globals.c

@@ -43,6 +43,7 @@ int g_viewMode = 0;
 int g_showingHint = 0;
 int g_suppressLineCount = 0;
 int g_execAtCursor = 0;
+int g_abortQuery = 0;
 wchar_t g_lastResultStatus[64] = L"";
 wchar_t g_findText[128] = L"";
 int g_searchMode = 0;

src/sqlite-ce-edit/globals.h

@@ -65,7 +65,7 @@ BOOL WINAPI GetSaveFileNameW(CE_OPENFILENAME*);
 ** Version
 **============================================================================*/
 
-#define SQLITECEDIT_VERSION L"0.4.0"
+#define SQLITECEDIT_VERSION L"0.5.0"
 
 /*============================================================================
 ** Menu IDs
@@ -86,6 +86,7 @@ BOOL WINAPI GetSaveFileNameW(CE_OPENFILENAME*);
 #define IDM_FINDNEXT 203
 #define IDM_EXECATCURSOR 204
 #define IDM_EXECATCURSOR_PLACEHOLDER 205
+#define IDM_STOP     206
 #define IDM_CLEAR    301
 #define IDM_VIEWQUERY  401
 #define IDM_VIEWRESULT 402
@@ -160,6 +161,7 @@ extern int g_viewMode;
 extern int g_showingHint;
 extern int g_suppressLineCount;
 extern int g_execAtCursor;
+extern int g_abortQuery;
 extern wchar_t g_lastResultStatus[64];
 extern wchar_t g_findText[128];
 extern int g_searchMode;

src/sqlite-ce-edit/main.c

@@ -19,7 +19,7 @@ static LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lPara
             RECT rc;
             int cbHeight;
             HMENU hMenu, hFile, hQuery;
-            TBBUTTON tbButtons[13];
+            TBBUTTON tbButtons[14];
 
             g_hBrushWhite = CreateSolidBrush(RGB(255, 255, 255));
 
@@ -135,7 +135,12 @@ static LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lPara
             tbButtons[12].fsState = TBSTATE_ENABLED;
             tbButtons[12].fsStyle = TBSTYLE_BUTTON;
 
-            CommandBar_AddButtons(g_hwndCB, 13, tbButtons);
+            tbButtons[13].iBitmap = TB_STOP;
+            tbButtons[13].idCommand = IDM_STOP;
+            tbButtons[13].fsState = 0;
+            tbButtons[13].fsStyle = TBSTYLE_BUTTON;
+            
+            CommandBar_AddButtons(g_hwndCB, 14, tbButtons);
 
             CommandBar_AddAdornments(g_hwndCB, 0, 0);
             cbHeight = CommandBar_Height(g_hwndCB);
@@ -230,6 +235,7 @@ static LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lPara
                 case IDM_IMPORTCEDB: DoImportCEDB(); break;
                 case IDM_EXIT:    SendMessage(hwnd, WM_CLOSE, 0, 0); break;
                 case IDM_EXECUTE: ExecuteQuery(); break;
+                case IDM_STOP: g_abortQuery = 1; break;
                 case IDM_EXECATCURSOR:
                     g_execAtCursor = !g_execAtCursor;
                     SendMessage(g_hwndCB, TB_CHECKBUTTON, IDM_EXECATCURSOR, g_execAtCursor);
@@ -298,6 +304,7 @@ static LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lPara
             if (GetKeyState(VK_CONTROL) < 0) {
                 if (wParam == 'O') { DoOpenQuery(); return 0; }
                 if (wParam == 'N') { DoFileNew(); return 0; }
+                if (wParam == 'C') { g_abortQuery = 1; return 0; }
             }
             if (wParam == VK_F5) { ExecuteQuery(); return 0; }
             if (wParam == VK_RETURN || wParam == VK_UP ||