GP-4949 Added Structure.setLength method and made structure editor performance improvements and various bug fixes.

Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/data/StructureDB.java

@@ -236,9 +236,57 @@ class StructureDB extends CompositeDB implements StructureInternal {
 		}
 	}
 
+	@Override
+	public void setLength(int len) {
+		if (len < 0) {
+			throw new IllegalArgumentException("Invalid length: " + len);
+		}
+		if (len == structLength || isPackingEnabled()) {
+			return;
+		}
+		lock.acquire();
+		try {
+			checkDeleted();
+			if (len < structLength) {
+				// identify index of first defined-component to be removed
+				int index = Collections.binarySearch(components, Integer.valueOf(len),
+					OffsetComparator.INSTANCE);
+				
+				if (index < 0) {
+					index = -index - 1;
+				}
+				else {
+					index = backupToFirstComponentContainingOffset(index, len);
+				}
+				int definedComponentCount = components.size();
+				if (index >= 0 && index < definedComponentCount) {
+					for (int i = index; i < definedComponentCount; i++) {
+						doDelete(components.get(i));
+					}
+					components = components.subList(0, index);
+				}
+			}
+			else {
+				numComponents += len - structLength;
+			}
+			structLength = len;
+			repack(false, false);
+			notifySizeChanged(false);
+		}
+		catch (IOException e) {
+			dataMgr.dbError(e);
+		}
+		finally {
+			lock.release();
+		}
+	}
+	
 	@Override
 	public void growStructure(int amount) {
-		if (isPackingEnabled()) {
+		if (amount < 0) {
+			throw new IllegalArgumentException("Invalid growth amount: " + amount);
+		}
+		if (amount == 0 || isPackingEnabled()) {
 			return;
 		}
 		lock.acquire();

Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/model/data/StandAloneDataTypeManager.java

@@ -914,6 +914,7 @@ public class StandAloneDataTypeManager extends DataTypeManagerDB implements Clos
 			}
 		}
 		if (restored) {
+			invalidateCache();
 			notifyRestored();
 		}
 	}

Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/model/data/Structure.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.
@@ -430,13 +430,22 @@ public interface Structure extends Composite {
 			String comment) throws IllegalArgumentException;
 
 	/**
-	 * Increases the size of the structure by the specified amount by adding undefined filler at the
+	 * Increases the size of the structure by the specified positive amount by adding undefined filler at the
 	 * end of the structure.  NOTE: This method only has an affect on non-packed structures.
 	 * 
 	 * @param amount the amount by which to grow the structure.
-	 * @throws IllegalArgumentException if amount < 1
+	 * @throws IllegalArgumentException if amount < 0
 	 */
 	public void growStructure(int amount);
+	
+	/**
+	 * Set the size of the structure to the specified byte-length.  If the length is shortened defined
+	 * components will be cleared and removed as required.
+	 * NOTE: This method only has an affect on non-packed structures.
+	 * @param length new structure length
+	 * @throws IllegalArgumentException if length < 0
+	 */
+	public void setLength(int length);
 
 	/**
 	 * <code>BitOffsetComparator</code> provides ability to compare an normalized bit offset (see

Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/model/data/StructureDataType.java

@@ -624,9 +624,43 @@ public class StructureDataType extends CompositeDataTypeImpl implements Structur
 		return dtc;
 	}
 
+	@Override
+	public void setLength(int len) {
+		if (len < 0) {
+			throw new IllegalArgumentException("Invalid length: " + len);
+		}
+		if (len == structLength || isPackingEnabled()) {
+			return;
+		}
+		if (len < structLength) {
+			// identify index of first defined-component to be removed
+			int index = Collections.binarySearch(components, Integer.valueOf(len),
+				OffsetComparator.INSTANCE);
+			if (index < 0) {
+				index = -index - 1;
+			}
+			else {
+				index = backupToFirstComponentContainingOffset(index, len);
+			}
+			int definedComponentCount = components.size();
+			if (index >= 0 && index < definedComponentCount) {
+				components = components.subList(0, index);
+			}
+		}
+		else {
+			numComponents += len - structLength;
+		}
+		structLength = len;
+		repack(false);
+		notifySizeChanged();
+	}
+	
 	@Override
 	public void growStructure(int amount) {
-		if (isPackingEnabled()) {
+		if (amount < 0) {
+			throw new IllegalArgumentException("Invalid growth amount: " + amount);
+		}
+		if (amount == 0 || isPackingEnabled()) {
 			return;
 		}
 		doGrowStructure(amount);

Ghidra/Framework/SoftwareModeling/src/test/java/ghidra/program/database/data/StructureDBTest.java

@@ -1449,6 +1449,40 @@ public class StructureDBTest extends AbstractGenericTest {
 		assertEquals(dtc1, barStruct.getComponent(6));
 
 	}
+	
+	@Test
+	public void testSetLength() {
+
+		assertEquals(8, struct.getLength());
+		assertEquals(4, struct.getNumComponents());
+		assertEquals(4, struct.getNumDefinedComponents());
+		
+		struct.setLength(20);
+		assertEquals(20, struct.getLength());
+		assertEquals(16, struct.getNumComponents());
+		assertEquals(4, struct.getNumDefinedComponents());
+		
+		// new length is offcut within 3rd component at offset 0x3 which should get cleared
+		struct.setLength(4);
+		assertEquals(4, struct.getLength());
+		assertEquals(3, struct.getNumComponents());
+		assertEquals(2, struct.getNumDefinedComponents());
+		
+		// Maximum length supported by GUI editor is ~Integer.MAX_VALUE/10
+		int len = Integer.MAX_VALUE / 10;
+		struct.setLength(len);
+		assertEquals(len, struct.getLength());
+		assertEquals(len - 1, struct.getNumComponents());
+		assertEquals(2, struct.getNumDefinedComponents());
+		
+		len /= 2;
+		struct.replaceAtOffset(len-2, WordDataType.dataType, -1, "x", null); // will be preserved below
+		struct.replaceAtOffset(len+2, WordDataType.dataType, -1, "y", null); // will be cleared below
+		struct.setLength(len);
+		assertEquals(len, struct.getLength());
+		assertEquals(len - 2, struct.getNumComponents());
+		assertEquals(3, struct.getNumDefinedComponents());
+	}
 
 	@Test
 	public void testDeleteMany() {