Try-fix traceroute panic (#8568)

Author: thebentern

src/modules/TraceRouteModule.cpp

@@ -11,6 +11,113 @@ extern graphics::Screen *screen;
 
 TraceRouteModule *traceRouteModule;
 
+void TraceRouteModule::setResultText(const String &text)
+{
+    resultText = text;
+    resultLines.clear();
+    resultLinesDirty = true;
+}
+
+void TraceRouteModule::clearResultLines()
+{
+    resultLines.clear();
+    resultLinesDirty = false;
+}
+#if HAS_SCREEN
+void TraceRouteModule::rebuildResultLines(OLEDDisplay *display)
+{
+    if (!display) {
+        resultLinesDirty = false;
+        return;
+    }
+
+    resultLines.clear();
+
+    if (resultText.length() == 0) {
+        resultLinesDirty = false;
+        return;
+    }
+
+    int maxWidth = display->getWidth() - 4;
+    if (maxWidth <= 0) {
+        resultLinesDirty = false;
+        return;
+    }
+
+    int start = 0;
+    int textLength = resultText.length();
+
+    while (start <= textLength) {
+        int newlinePos = resultText.indexOf('\n', start);
+        String segment;
+
+        if (newlinePos != -1) {
+            segment = resultText.substring(start, newlinePos);
+            start = newlinePos + 1;
+        } else {
+            segment = resultText.substring(start);
+            start = textLength + 1;
+        }
+
+        if (segment.length() == 0) {
+            resultLines.push_back("");
+            continue;
+        }
+
+        if (display->getStringWidth(segment) <= maxWidth) {
+            resultLines.push_back(segment);
+            continue;
+        }
+
+        String remaining = segment;
+
+        while (remaining.length() > 0) {
+            String tempLine = "";
+            int lastGoodBreak = -1;
+            bool lineComplete = false;
+
+            for (int i = 0; i < static_cast<int>(remaining.length()); i++) {
+                char ch = remaining.charAt(i);
+                String testLine = tempLine + ch;
+
+                if (display->getStringWidth(testLine) > maxWidth) {
+                    if (lastGoodBreak >= 0) {
+                        resultLines.push_back(remaining.substring(0, lastGoodBreak + 1));
+                        remaining = remaining.substring(lastGoodBreak + 1);
+                        lineComplete = true;
+                        break;
+                    } else if (tempLine.length() > 0) {
+                        resultLines.push_back(tempLine);
+                        remaining = remaining.substring(i);
+                        lineComplete = true;
+                        break;
+                    } else {
+                        resultLines.push_back(String(ch));
+                        remaining = remaining.substring(i + 1);
+                        lineComplete = true;
+                        break;
+                    }
+                } else {
+                    tempLine = testLine;
+                    if (ch == ' ' || ch == '>' || ch == '<' || ch == '-' || ch == '(' || ch == ')' || ch == ',') {
+                        lastGoodBreak = i;
+                    }
+                }
+            }
+
+            if (!lineComplete) {
+                if (tempLine.length() > 0) {
+                    resultLines.push_back(tempLine);
+                }
+                break;
+            }
+        }
+    }
+
+    resultLinesDirty = false;
+}
+#endif
+
 bool TraceRouteModule::handleReceivedProtobuf(const meshtastic_MeshPacket &mp, meshtastic_RouteDiscovery *r)
 {
     // We only alter the packet in alterReceivedProtobuf()
@@ -406,7 +513,7 @@ bool TraceRouteModule::startTraceRoute(NodeNum node)
     if (node == 0 || node == NODENUM_BROADCAST) {
         LOG_ERROR("Invalid node number for trace route: 0x%08x", node);
         runState = TRACEROUTE_STATE_RESULT;
-        resultText = "Invalid node";
+        setResultText("Invalid node");
         resultShowTime = millis();
         tracingNode = 0;
 
@@ -420,7 +527,7 @@ bool TraceRouteModule::startTraceRoute(NodeNum node)
     if (node == nodeDB->getNodeNum()) {
         LOG_ERROR("Cannot trace route to self: 0x%08x", node);
         runState = TRACEROUTE_STATE_RESULT;
-        resultText = "Cannot trace self";
+        setResultText("Cannot trace self");
         resultShowTime = millis();
         tracingNode = 0;
 
@@ -447,6 +554,8 @@ bool TraceRouteModule::startTraceRoute(NodeNum node)
         unsigned long wait = (cooldownMs - (now - lastTraceRouteTime)) / 1000;
         bannerText = String("Wait for ") + String(wait) + String("s");
         runState = TRACEROUTE_STATE_COOLDOWN;
+        resultText = "";
+        clearResultLines();
 
         requestFocus();
         UIFrameEvent e;
@@ -459,6 +568,8 @@ bool TraceRouteModule::startTraceRoute(NodeNum node)
     tracingNode = node;
     lastTraceRouteTime = now;
     runState = TRACEROUTE_STATE_TRACKING;
+    resultText = "";
+    clearResultLines();
     bannerText = String("Tracing ") + getNodeName(node);
 
     LOG_INFO("TraceRoute UI: Starting trace route to node 0x%08x, requesting focus", node);
@@ -501,7 +612,7 @@ bool TraceRouteModule::startTraceRoute(NodeNum node)
         } else {
             LOG_ERROR("MeshService is NULL!");
             runState = TRACEROUTE_STATE_RESULT;
-            resultText = "Service unavailable";
+            setResultText("Service unavailable");
             resultShowTime = millis();
             tracingNode = 0;
 
@@ -514,7 +625,7 @@ bool TraceRouteModule::startTraceRoute(NodeNum node)
     } else {
         LOG_ERROR("Failed to allocate TraceRoute packet from router");
         runState = TRACEROUTE_STATE_RESULT;
-        resultText = "Failed to send";
+        setResultText("Failed to send");
         resultShowTime = millis();
         tracingNode = 0;
 
@@ -532,7 +643,7 @@ void TraceRouteModule::launch(NodeNum node)
     if (node == 0 || node == NODENUM_BROADCAST) {
         LOG_ERROR("Invalid node number for trace route: 0x%08x", node);
         runState = TRACEROUTE_STATE_RESULT;
-        resultText = "Invalid node";
+        setResultText("Invalid node");
         resultShowTime = millis();
         tracingNode = 0;
 
@@ -546,7 +657,7 @@ void TraceRouteModule::launch(NodeNum node)
     if (node == nodeDB->getNodeNum()) {
         LOG_ERROR("Cannot trace route to self: 0x%08x", node);
         runState = TRACEROUTE_STATE_RESULT;
-        resultText = "Cannot trace self";
+        setResultText("Cannot trace self");
         resultShowTime = millis();
         tracingNode = 0;
 
@@ -568,6 +679,8 @@ void TraceRouteModule::launch(NodeNum node)
         unsigned long wait = (cooldownMs - (now - lastTraceRouteTime)) / 1000;
         bannerText = String("Wait for ") + String(wait) + String("s");
         runState = TRACEROUTE_STATE_COOLDOWN;
+        resultText = "";
+        clearResultLines();
 
         requestFocus();
         UIFrameEvent e;
@@ -580,6 +693,8 @@ void TraceRouteModule::launch(NodeNum node)
     runState = TRACEROUTE_STATE_TRACKING;
     tracingNode = node;
     lastTraceRouteTime = now;
+    resultText = "";
+    clearResultLines();
     bannerText = String("Tracing ") + getNodeName(node);
 
     requestFocus();
@@ -614,22 +729,22 @@ void TraceRouteModule::launch(NodeNum node)
         } else {
             LOG_ERROR("MeshService is NULL!");
             runState = TRACEROUTE_STATE_RESULT;
-            resultText = "Service unavailable";
+            setResultText("Service unavailable");
             resultShowTime = millis();
             tracingNode = 0;
         }
     } else {
         LOG_ERROR("Failed to allocate TraceRoute packet from router");
         runState = TRACEROUTE_STATE_RESULT;
-        resultText = "Failed to send";
+        setResultText("Failed to send");
         resultShowTime = millis();
         tracingNode = 0;
     }
 }
 
 void TraceRouteModule::handleTraceRouteResult(const String &result)
 {
-    resultText = result;
+    setResultText(result);
     runState = TRACEROUTE_STATE_RESULT;
     resultShowTime = millis();
     tracingNode = 0;
@@ -679,83 +794,15 @@ void TraceRouteModule::drawFrame(OLEDDisplay *display, OLEDDisplayUiState *state
         display->setFont(FONT_SMALL);
 
         if (resultText.length() > 0) {
-            std::vector<String> lines;
-            String currentLine = "";
-            int maxWidth = display->getWidth() - 4;
-
-            int start = 0;
-            int newlinePos = resultText.indexOf('\n', start);
-
-            while (newlinePos != -1 || start < static_cast<int>(resultText.length())) {
-                String segment;
-                if (newlinePos != -1) {
-                    segment = resultText.substring(start, newlinePos);
-                    start = newlinePos + 1;
-                    newlinePos = resultText.indexOf('\n', start);
-                } else {
-                    segment = resultText.substring(start);
-                    start = resultText.length();
-                }
-
-                if (display->getStringWidth(segment) <= maxWidth) {
-                    lines.push_back(segment);
-                } else {
-                    // Try to break at better positions (space, >, <, -)
-                    String remaining = segment;
-
-                    while (remaining.length() > 0) {
-                        String tempLine = "";
-                        int lastGoodBreak = -1;
-                        bool lineComplete = false;
-
-                        for (int i = 0; i < static_cast<int>(remaining.length()); i++) {
-                            char ch = remaining.charAt(i);
-                            String testLine = tempLine + ch;
-
-                            if (display->getStringWidth(testLine) > maxWidth) {
-                                if (lastGoodBreak >= 0) {
-                                    // Break at the last good position
-                                    lines.push_back(remaining.substring(0, lastGoodBreak + 1));
-                                    remaining = remaining.substring(lastGoodBreak + 1);
-                                    lineComplete = true;
-                                    break;
-                                } else if (tempLine.length() > 0) {
-                                    lines.push_back(tempLine);
-                                    remaining = remaining.substring(i);
-                                    lineComplete = true;
-                                    break;
-                                } else {
-                                    // Single character exceeds width
-                                    lines.push_back(String(ch));
-                                    remaining = remaining.substring(i + 1);
-                                    lineComplete = true;
-                                    break;
-                                }
-                            } else {
-                                tempLine = testLine;
-                                // Mark good break positions
-                                if (ch == ' ' || ch == '>' || ch == '<' || ch == '-' || ch == '(' || ch == ')') {
-                                    lastGoodBreak = i;
-                                }
-                            }
-                        }
-
-                        if (!lineComplete) {
-                            // Reached end of remaining text
-                            if (tempLine.length() > 0) {
-                                lines.push_back(tempLine);
-                            }
-                            break;
-                        }
-                    }
-                }
+            if (resultLinesDirty) {
+                rebuildResultLines(display);
             }
 
             int lineHeight = FONT_HEIGHT_SMALL + 1; // Use proper font height with 1px spacing
-            for (size_t i = 0; i < lines.size(); i++) {
+            for (size_t i = 0; i < resultLines.size(); i++) {
                 int lineY = contentStartY + (i * lineHeight);
                 if (lineY + FONT_HEIGHT_SMALL <= display->getHeight()) {
-                    display->drawString(x + 2, lineY, lines[i]);
+                    display->drawString(x + 2, lineY, resultLines[i]);
                 }
             }
         }
@@ -779,7 +826,7 @@ int32_t TraceRouteModule::runOnce()
     if (runState == TRACEROUTE_STATE_TRACKING && now - lastTraceRouteTime > trackingTimeoutMs) {
         LOG_INFO("TraceRoute timeout, no response received");
         runState = TRACEROUTE_STATE_RESULT;
-        resultText = "No response received";
+        setResultText("No response received");
         resultShowTime = now;
         tracingNode = 0;
 
@@ -815,6 +862,8 @@ int32_t TraceRouteModule::runOnce()
             // Cooldown finished
             LOG_INFO("TraceRoute cooldown finished, returning to IDLE");
             runState = TRACEROUTE_STATE_IDLE;
+            resultText = "";
+            clearResultLines();
             bannerText = "";
             UIFrameEvent e;
             e.action = UIFrameEvent::Action::REGENERATE_FRAMESET;
@@ -828,6 +877,7 @@ int32_t TraceRouteModule::runOnce()
             LOG_INFO("TraceRoute result display timeout, returning to IDLE");
             runState = TRACEROUTE_STATE_IDLE;
             resultText = "";
+            clearResultLines();
             bannerText = "";
             tracingNode = 0;
             UIFrameEvent e;

src/modules/TraceRouteModule.h

@@ -7,6 +7,7 @@
 #if HAS_SCREEN
 #include "OLEDDisplayUi.h"
 #endif
+#include <vector>
 
 #define ROUTE_SIZE sizeof(((meshtastic_RouteDiscovery *)0)->route) / sizeof(((meshtastic_RouteDiscovery *)0)->route[0])
 
@@ -49,6 +50,11 @@ class TraceRouteModule : public ProtobufModule<meshtastic_RouteDiscovery>,
     virtual int32_t runOnce() override;
 
   private:
+    void setResultText(const String &text);
+    void clearResultLines();
+#if HAS_SCREEN
+    void rebuildResultLines(OLEDDisplay *display);
+#endif
     // Call to add unknown hops (e.g. when a node couldn't decrypt it) to the route based on hopStart and current hopLimit
     void insertUnknownHops(meshtastic_MeshPacket &p, meshtastic_RouteDiscovery *r, bool isTowardsDestination);
 
@@ -74,6 +80,8 @@ class TraceRouteModule : public ProtobufModule<meshtastic_RouteDiscovery>,
     unsigned long trackingTimeoutMs = 10000;
     String bannerText;
     String resultText;
+    std::vector<String> resultLines;
+    bool resultLinesDirty = false;
     NodeNum tracingNode = 0;
     bool initialized = false;
 };