debugger: rework WatchModel

It's one model for all locals, watch, return, tooltip and inspector
data. This allows more streamlined code paths and better isolation
of the model data from the WatchHandler. WatchItems are now registered
in a hash indexed by iname, so inames can be used as the primary
handle to watch data in the WatchHandler interface.

Change-Id: Idac0a808b5d785307496d1de4198a1f2e9ce3880
Reviewed-by: Aurindam Jana <aurindam.jana@nokia.com>

1 files changed, 46 insertions, 80 deletions

diff --git a/src/plugins/debugger/gdb/gdbengine.cpp b/src/plugins/debugger/gdb/gdbengine.cpp
index 83ee073d05..1a3e87f409 100644
--- a/src/plugins/debugger/gdb/gdbengine.cpp
+++ b/src/plugins/debugger/gdb/gdbengine.cpp
@@ -255,7 +255,6 @@ GdbEngine::GdbEngine(const DebuggerStartParameters &startParameters,
     m_oldestAcceptableToken = -1;
     m_nonDiscardableCount = 0;
     m_outputCodec = QTextCodec::codecForLocale();
-    m_pendingWatchRequests = 0;
     m_pendingBreakpointRequests = 0;
     m_commandsDoneCallback = 0;
     m_stackNeeded = false;
@@ -263,6 +262,7 @@ GdbEngine::GdbEngine(const DebuggerStartParameters &startParameters,
     m_disassembleUsesComma = false;
     m_actingOnExpectedStop = false;
     m_fullStartDone = false;
+    m_forceAsyncModel = false;
 
     invalidateSourcesList();
 
@@ -788,7 +788,8 @@ void GdbEngine::readGdbStandardOutput()
     int newstart = 0;
     int scan = m_inbuffer.size();
 
-    m_inbuffer.append(gdbProc()->readAllStandardOutput());
+    QByteArray out = gdbProc()->readAllStandardOutput();
+    m_inbuffer.append(out);
 
     // This can trigger when a dialog starts a nested event loop.
     if (m_busy)
@@ -811,7 +812,8 @@ void GdbEngine::readGdbStandardOutput()
                 continue;
         }
         m_busy = true;
-        handleResponse(QByteArray::fromRawData(m_inbuffer.constData() + start, end - start));
+        QByteArray ba = QByteArray::fromRawData(m_inbuffer.constData() + start, end - start);
+        handleResponse(ba);
         m_busy = false;
     }
     m_inbuffer.clear();
@@ -903,17 +905,13 @@ void GdbEngine::postCommandHelper(const GdbCommand &cmd)
         return;
     }
 
-    if (cmd.flags & RebuildWatchModel) {
-        ++m_pendingWatchRequests;
-        PENDING_DEBUG("   WATCH MODEL:" << cmd.command << "=>" << cmd.callbackName
-                      << "INCREMENTS PENDING TO" << m_pendingWatchRequests);
-    } else if (cmd.flags & RebuildBreakpointModel) {
+    if (cmd.flags & RebuildBreakpointModel) {
         ++m_pendingBreakpointRequests;
         PENDING_DEBUG("   BRWAKPOINT MODEL:" << cmd.command << "=>" << cmd.callbackName
                       << "INCREMENTS PENDING TO" << m_pendingBreakpointRequests);
     } else {
         PENDING_DEBUG("   OTHER (IN):" << cmd.command << "=>" << cmd.callbackName
-                      << "LEAVES PENDING WATCH AT" << m_pendingWatchRequests
+                      << "LEAVES PENDING WATCH AT" << m_uncompleted.size()
                       << "LEAVES PENDING BREAKPOINT AT" << m_pendingBreakpointRequests);
     }
 
@@ -1055,7 +1053,6 @@ void GdbEngine::commandTimeout()
         if (mb->exec() == QMessageBox::Ok) {
             showMessage(_("KILLING DEBUGGER AS REQUESTED BY USER"));
             // This is an undefined state, so we just pull the emergency brake.
-            watchHandler()->endCycle();
             gdbProc()->kill();
         } else {
             showMessage(_("CONTINUE DEBUGGER AS REQUESTED BY USER"));
@@ -1205,25 +1202,17 @@ void GdbEngine::handleResultRecord(GdbResponse *response)
     else if (cmd.adapterCallback)
         (m_gdbAdapter->*cmd.adapterCallback)(*response);
 
-    if (cmd.flags & RebuildWatchModel) {
-        --m_pendingWatchRequests;
-        PENDING_DEBUG("   WATCH" << cmd.command << "=>" << cmd.callbackName
-                      << "DECREMENTS PENDING WATCH TO" << m_pendingWatchRequests);
-        if (m_pendingWatchRequests <= 0) {
-            PENDING_DEBUG("\n\n ... AND TRIGGERS WATCH MODEL UPDATE\n");
-            rebuildWatchModel();
-        }
-    } else if (cmd.flags & RebuildBreakpointModel) {
+    if (cmd.flags & RebuildBreakpointModel) {
         --m_pendingBreakpointRequests;
         PENDING_DEBUG("   BREAKPOINT" << cmd.command << "=>" << cmd.callbackName
-                      << "DECREMENTS PENDING TO" << m_pendingWatchRequests);
+                      << "DECREMENTS PENDING TO" << m_uncompleted.size());
         if (m_pendingBreakpointRequests <= 0) {
             PENDING_DEBUG("\n\n ... AND TRIGGERS BREAKPOINT MODEL UPDATE\n");
             attemptBreakpointSynchronization();
         }
     } else {
         PENDING_DEBUG("   OTHER (OUT):" << cmd.command << "=>" << cmd.callbackName
-                      << "LEAVES PENDING WATCH AT" << m_pendingWatchRequests
+                      << "LEAVES PENDING WATCH AT" << m_uncompleted.size()
                       << "LEAVES PENDING BREAKPOINT AT" << m_pendingBreakpointRequests);
     }
 
@@ -3918,10 +3907,10 @@ bool GdbEngine::supportsThreads() const
 //
 //////////////////////////////////////////////////////////////////////
 
-bool GdbEngine::showToolTip()
+void GdbEngine::showToolTip()
 {
     if (m_toolTipContext.isNull())
-        return false;
+        return;
     const QString expression = m_toolTipContext->expression;
     const QByteArray iname = tooltipIName(m_toolTipContext->expression);
     if (DebuggerToolTipManager::debug())
@@ -3929,15 +3918,15 @@ bool GdbEngine::showToolTip()
 
     if (!debuggerCore()->boolSetting(UseToolTipsInMainEditor)) {
         watchHandler()->removeData(iname);
-        return true;
+        return;
     }
 
     if (!watchHandler()->isValidToolTip(iname)) {
         watchHandler()->removeData(iname);
-        return true;
+        return;
     }
     DebuggerToolTipWidget *tw = new DebuggerToolTipWidget;
-    tw->setDebuggerModel(TooltipsWatch);
+    tw->setDebuggerModel(TooltipType);
     tw->setExpression(expression);
     tw->setContext(*m_toolTipContext);
     tw->acquireEngine(this);
@@ -3945,7 +3934,6 @@ bool GdbEngine::showToolTip()
                                                     m_toolTipContext->editor, tw);
     // Prevent tooltip from re-occurring (classic GDB, QTCREATORBUG-4711).
     m_toolTipContext.reset();
-    return true;
 }
 
 QString GdbEngine::tooltipExpression() const
@@ -4034,7 +4022,6 @@ bool GdbEngine::setToolTipExpression(const QPoint &mousePos,
         toolTip.exp = exp.toLatin1();
         toolTip.name = exp;
         toolTip.iname = tooltipIName(exp);
-        watchHandler()->removeData(toolTip.iname);
         watchHandler()->insertData(toolTip);
     }
     return true;
@@ -4071,19 +4058,12 @@ bool GdbEngine::hasDebuggingHelperForType(const QByteArray &type) const
     return m_dumperHelper.type(type) != DumperHelper::UnknownType;
 }
 
-
 void GdbEngine::updateWatchData(const WatchData &data, const WatchUpdateFlags &flags)
 {
     if (isSynchronous()) {
         // This should only be called for fresh expanded items, not for
         // items that had their children retrieved earlier.
         //qDebug() << "\nUPDATE WATCH DATA: " << data.toString() << "\n";
-#if 0
-        WatchData data1 = data;
-        data1.setAllUnneeded();
-        insertData(data1);
-        rebuildModel();
-#else
         if (data.iname.endsWith("."))
             return;
 
@@ -4106,53 +4086,26 @@ void GdbEngine::updateWatchData(const WatchData &data, const WatchUpdateFlags &f
         // triggered e.g. by manually entered command in the gdb console?
         //qDebug() << "TRY PARTIAL: " << flags.tryIncremental
         //        << hasPython()
-        //        << (m_pendingWatchRequests == 0)
         //        << (m_pendingBreakpointRequests == 0);
 
         UpdateParameters params;
         params.tooltipOnly = data.iname.startsWith("tooltip");
         params.tryPartial = flags.tryIncremental
                 && hasPython()
-                && m_pendingWatchRequests == 0
                 && m_pendingBreakpointRequests == 0;
         params.varList = data.iname;
 
         updateLocalsPython(params);
-#endif
     } else {
-        // Bump requests to avoid model rebuilding during the nested
-        // updateWatchModel runs.
-        ++m_pendingWatchRequests;
-        PENDING_DEBUG("UPDATE WATCH BUMPS PENDING UP TO " << m_pendingWatchRequests);
-#if 1
-        QMetaObject::invokeMethod(this, "updateWatchDataHelper",
-            Qt::QueuedConnection, Q_ARG(WatchData, data));
-#else
-        updateWatchDataHelper(data);
-#endif
+        PENDING_DEBUG("UPDATE WATCH BUMPS PENDING UP TO " << m_uncompleted.size());
+        updateSubItemClassic(data);
     }
 }
 
-void GdbEngine::updateWatchDataHelper(const WatchData &data)
-{
-    //m_pendingRequests = 0;
-    PENDING_DEBUG("UPDATE WATCH DATA");
-#    if DEBUG_PENDING
-    //qDebug() << "##############################################";
-    qDebug() << "UPDATE MODEL, FOUND INCOMPLETE:";
-    //qDebug() << data.toString();
-#    endif
-
-    updateSubItemClassic(data);
-    //PENDING_DEBUG("INTERNAL TRIGGERING UPDATE WATCH MODEL");
-    --m_pendingWatchRequests;
-    PENDING_DEBUG("UPDATE WATCH DONE BUMPS PENDING DOWN TO " << m_pendingWatchRequests);
-    if (m_pendingWatchRequests <= 0)
-        rebuildWatchModel();
-}
-
 void GdbEngine::rebuildWatchModel()
 {
+    QTC_CHECK(m_completed.isEmpty());
+    QTC_CHECK(m_uncompleted.isEmpty());
     static int count = 0;
     ++count;
     if (!isSynchronous())
@@ -4162,7 +4115,6 @@ void GdbEngine::rebuildWatchModel()
         showMessage(LogWindow::logTimeStamp(), LogMiscInput);
     showMessage(_("<Rebuild Watchmodel %1>").arg(count), LogMiscInput);
     showStatusMessage(tr("Finished retrieving data"), 400);
-    watchHandler()->endCycle();
     showToolTip();
     handleAutoTests();
 }
@@ -4332,15 +4284,23 @@ WatchData GdbEngine::localVariable(const GdbMi &item,
     return data;
 }
 
-void GdbEngine::insertData(const WatchData &data0)
+void GdbEngine::insertData(const WatchData &data)
 {
-    PENDING_DEBUG("INSERT DATA" << data0.toString());
-    WatchData data = data0;
-    if (data.value.startsWith(QLatin1String("mi_cmd_var_create:"))) {
-        qDebug() << "BOGUS VALUE:" << data.toString();
-        return;
+    PENDING_DEBUG("INSERT DATA" << data.toString());
+    if (data.isSomethingNeeded()) {
+        m_uncompleted.insert(data.iname);
+        WatchUpdateFlags flags;
+        flags.tryIncremental = true;
+        updateWatchData(data, flags);
+    } else {
+        m_completed.append(data);
+        m_uncompleted.remove(data.iname);
+        if (m_uncompleted.isEmpty()) {
+            watchHandler()->insertData(m_completed);
+            m_completed.clear();
+            rebuildWatchModel();
+        }
     }
-    watchHandler()->insertData(data);
 }
 
 void GdbEngine::assignValueInDebugger(const WatchData *data,
@@ -4901,12 +4861,6 @@ bool GdbEngine::startGdb(const QStringList &args, const QString &settingsIdHint)
 
     postCommand("disassemble 0 0", ConsoleCommand, CB(handleDisassemblerCheck));
 
-    if (sp.breakOnMain) {
-        QByteArray cmd = "tbreak ";
-        cmd += sp.toolChainAbi.os() == Abi::WindowsOS ? "qMain" : "main";
-        postCommand(cmd);
-    }
-
     if (attemptQuickStart()) {
         postCommand("set auto-solib-add off", ConsoleCommand);
     } else {
@@ -4941,6 +4895,9 @@ void GdbEngine::loadInitScript()
 
 void GdbEngine::loadPythonDumpers()
 {
+    if (m_forceAsyncModel)
+        return;
+
     const QByteArray dumperSourcePath =
         Core::ICore::resourcePath().toLocal8Bit() + "/dumper/";
 
@@ -5091,6 +5048,12 @@ void GdbEngine::handleInferiorPrepared()
 
     QTC_ASSERT(state() == InferiorSetupRequested, qDebug() << state());
 
+    if (sp.breakOnMain) {
+        QByteArray cmd = "tbreak ";
+        cmd += sp.toolChainAbi.os() == Abi::WindowsOS ? "qMain" : "main";
+        postCommand(cmd);
+    }
+
     // Initial attempt to set breakpoints.
     if (sp.startMode != AttachCore) {
         showStatusMessage(tr("Setting breakpoints..."));
@@ -5361,6 +5324,9 @@ void GdbEngine::requestDebugInformation(const DebugInfoTask &task)
 
 bool GdbEngine::attemptQuickStart() const
 {
+    if (m_forceAsyncModel)
+        return false;
+
     // Don't try if the user does not ask for it.
     if (!debuggerCore()->boolSetting(AttemptQuickStart))
         return false;