Merge remote-tracking branch 'origin/GP-6298_Dan_fixSnapshotIsNull' into patch

Ghidra/Debug/Debugger/src/main/java/ghidra/app/plugin/core/debug/gui/time/DebuggerSnapshotTablePanel.java

@@ -228,16 +228,15 @@ public class DebuggerSnapshotTablePanel extends JPanel {
 			}
 
 			TraceSnapshot snapshot = row.getSnapshot();
-			if (snapshot.getSchedule().isSnapOnly() ||
-				snapshot.getVersion() >= current.getTrace().getEmulatorCacheVersion()) {
+			if (snapshot.isStale(true)) {
+				setForeground(
+					data.isSelected() ? COLOR_FOREGROUND_STALE_SEL : COLOR_FOREGROUND_STALE);
+			}
+			else {
 				JTable table = data.getTable();
 				setForeground(
 					data.isSelected() ? table.getSelectionForeground() : table.getForeground());
 			}
-			else {
-				setForeground(
-					data.isSelected() ? COLOR_FOREGROUND_STALE_SEL : COLOR_FOREGROUND_STALE);
-			}
 
 			return this;
 		}

Ghidra/Debug/Debugger/src/main/java/ghidra/app/plugin/core/debug/service/emulation/DebuggerEmulationServicePlugin.java

@@ -688,7 +688,7 @@ public class DebuggerEmulationServicePlugin extends Plugin implements DebuggerEm
 		TraceSchedule time = key.time;
 
 		TraceSnapshot tracePrefix = trace.getTimeManager().findSnapshotWithNearestPrefix(time);
-		if (tracePrefix.getSchedule().isSnapOnly()) {
+		if (tracePrefix != null && tracePrefix.isSnapOnly(true)) {
 			tracePrefix = null;
 		}
 		Map.Entry<CacheKey, CachedEmulator> cachePrefix = findNearestPrefix(key);

Ghidra/Debug/Framework-TraceModeling/src/main/java/ghidra/trace/database/time/DBTraceSnapshot.java

@@ -227,6 +227,28 @@ public class DBTraceSnapshot extends DBAnnotatedObject implements TraceSnapshot
 		}
 	}
 
+	@Override
+	public boolean isSnapOnly(boolean whenInconsistent) {
+		if (schedule == null && key < 0) {
+			return whenInconsistent;
+		}
+		return schedule == null || schedule.isSnapOnly();
+	}
+
+	@Override
+	public boolean isStale(boolean whenInconsistent) {
+		if (schedule == null) {
+			if (key < 0) {
+				return whenInconsistent;
+			}
+			return false; // A recorded snapshot
+		}
+		if (schedule.isSnapOnly()) {
+			return false;
+		}
+		return version < manager.trace.getEmulatorCacheVersion();
+	}
+
 	@Override
 	public void delete() {
 		manager.deleteSnapshot(this);

Ghidra/Debug/Framework-TraceModeling/src/main/java/ghidra/trace/model/time/TraceSnapshot.java

@@ -4,9 +4,9 @@
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
- * 
+ *
  *      http://www.apache.org/licenses/LICENSE-2.0
- * 
+ *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
@@ -43,7 +43,7 @@ public interface TraceSnapshot {
 	/**
 	 * Get the description of the snapshot
 	 * 
-	 * @return
+	 * @return the description
 	 */
 	String getDescription();
 
@@ -131,6 +131,34 @@ public interface TraceSnapshot {
 	 */
 	void setVersion(long version);
 
+	/**
+	 * Check if a snapshot involves any steps of emulation
+	 * <p>
+	 * A scratch snapshot, i.e., whose key is negative, without a schedule set is considered
+	 * inconsistent.
+	 * 
+	 * @param whenInconsistent the value to return for a scratch snapshot without a set schedule
+	 * @return true if no emulation is involved
+	 */
+	boolean isSnapOnly(boolean whenInconsistent);
+
+	/**
+	 * For an emulated snapshot, check if re-emulation is necessary to produce an up-to-date
+	 * snapshot.
+	 * <p>
+	 * For non-emulated snapshots, this always returns false. A non-emulated snapshot is a snapshot
+	 * whose schedule includes no emulation steps. An emulation snapshot is stale when its version
+	 * is less than the trace's emulator cache version. A scratch snapshot, i.e., whose key is
+	 * negative, without a schedule set is considered inconsistent.
+	 * 
+	 * @param whenInconsistent the value to return for a scratch snapshot without a set schedule
+	 * @return true if re-emulation is needed
+	 * @see #getVersion()
+	 * @see #setVersion(long)
+	 * @see Trace#getEmulatorCacheVersion()
+	 */
+	boolean isStale(boolean whenInconsistent);
+
 	/**
 	 * Delete this snapshot
 	 *