ctf: add Dynamic Length Arrays

Change-Id: Icb35ac1c931e398be30debfa45c539f8c9fcd245
Signed-off-by: Matthew Khouzam <matthew.khouzam@ericsson.com>

Author: MatthewKhouzam

ctf/org.eclipse.tracecompass.ctf.core/src/org/eclipse/tracecompass/internal/ctf/core/event/metadata/tsdl/dynamicarray/DynamicLengthArrayParser.java

@@ -0,0 +1,121 @@
+/*******************************************************************************
+ * Copyright (c) 2025 Ericsson
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License 2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *******************************************************************************/
+package org.eclipse.tracecompass.internal.ctf.core.event.metadata.tsdl.dynamicarray;
+
+import org.eclipse.jdt.annotation.NonNullByDefault;
+import org.eclipse.tracecompass.ctf.core.event.metadata.DeclarationScope;
+import org.eclipse.tracecompass.ctf.core.event.types.IDeclaration;
+import org.eclipse.tracecompass.ctf.core.trace.CTFTrace;
+import org.eclipse.tracecompass.internal.ctf.core.event.metadata.AbstractScopedCommonTreeParser;
+import org.eclipse.tracecompass.internal.ctf.core.event.metadata.JsonStructureFieldMemberMetadataNode;
+import org.eclipse.tracecompass.internal.ctf.core.event.metadata.ParseException;
+import org.eclipse.tracecompass.internal.ctf.core.event.metadata.tsdl.TypeAliasParser;
+import org.eclipse.tracecompass.internal.ctf.core.event.types.ICTFMetadataNode;
+import org.eclipse.tracecompass.internal.ctf.core.event.types.SequenceDeclaration;
+import org.eclipse.tracecompass.internal.ctf.core.utils.JsonMetadataStrings;
+
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+
+/**
+ * A dynamic-length array field class describes dynamic-length array fields.
+ *
+ * @author Matthew Khouzam
+ */
+public final class DynamicLengthArrayParser extends AbstractScopedCommonTreeParser {
+
+    /**
+     * Instance
+     */
+    public static final DynamicLengthArrayParser INSTANCE = new DynamicLengthArrayParser();
+
+    private DynamicLengthArrayParser() {
+    }
+
+    @Override
+    public IDeclaration parse(ICTFMetadataNode node, ICommonTreeParserParameter param) throws ParseException {
+        if (!(node instanceof JsonStructureFieldMemberMetadataNode)) {
+            throw new ParseException("Dynamic-length array only supported in JSON metadata"); //$NON-NLS-1$
+        }
+        if (!(param instanceof Param)) {
+            throw new IllegalArgumentException("Param must be a " + Param.class.getCanonicalName()); //$NON-NLS-1$
+        }
+
+        JsonStructureFieldMemberMetadataNode member = (JsonStructureFieldMemberMetadataNode) node;
+        JsonElement fieldClassElement = member.getFieldClass();
+        if (fieldClassElement == null || !fieldClassElement.isJsonObject()) {
+            throw new ParseException(getClass().getName() + " fieldclass must be a json object."); //$NON-NLS-1$
+        }
+        JsonObject fieldClass = member.getFieldClass().getAsJsonObject();
+
+        JsonElement lengthFieldLocation = fieldClass.get(JsonMetadataStrings.LENGTH_FIELD_LOCATION);
+        if (lengthFieldLocation == null) {
+            throw new ParseException("Dynamic-length array requires length-field-location property"); //$NON-NLS-1$
+        }
+
+        JsonElement elementFieldClass = fieldClass.get(JsonMetadataStrings.ELEMENT_FIELD_CLASS);
+        if (elementFieldClass == null) {
+            throw new ParseException("Dynamic-length array requires element-field-class property"); //$NON-NLS-1$
+        }
+
+        JsonElement pathElement = lengthFieldLocation.getAsJsonObject().get(JsonMetadataStrings.PATH);
+        String lengthName = pathElement.isJsonArray() ?
+            pathElement.getAsJsonArray().get(pathElement.getAsJsonArray().size() - 1).getAsString() :
+            pathElement.getAsString();
+        CTFTrace trace = ((Param) param).getTrace();
+        DeclarationScope scope = ((Param) param).getScope();
+
+        JsonStructureFieldMemberMetadataNode elementNode = new JsonStructureFieldMemberMetadataNode(node, "", "", "", elementFieldClass.getAsJsonObject()); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
+        IDeclaration elementDeclaration = TypeAliasParser.INSTANCE.parse(elementNode, new TypeAliasParser.Param(trace, scope));
+
+        return new SequenceDeclaration(lengthName, elementDeclaration);
+    }
+
+    /**
+     * Parameters for the dynamic-length array parser
+     */
+    @NonNullByDefault
+    public static final class Param implements ICommonTreeParserParameter {
+        private final CTFTrace fTrace;
+        private final DeclarationScope fScope;
+
+        /**
+         * Parameter constructor
+         *
+         * @param trace
+         *            the trace
+         * @param scope
+         *            the declaration scope
+         */
+        public Param(CTFTrace trace, DeclarationScope scope) {
+            fTrace = trace;
+            fScope = scope;
+        }
+
+        /**
+         * Get the trace
+         *
+         * @return the trace
+         */
+        public CTFTrace getTrace() {
+            return fTrace;
+        }
+
+        /**
+         * Get the scope
+         *
+         * @return the scope
+         */
+        public DeclarationScope getScope() {
+            return fScope;
+        }
+    }
+}