Add in a (disabled) test for bug #43670 (not yet fixed)

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@589417 13f79535-47bb-0310-9956-ffa450edef68

src/scratchpad/src/org/apache/poi/hdgf/chunks/ChunkFactory.java

@@ -107,6 +107,12 @@ public class ChunkFactory {
 		// Create the header
 		ChunkHeader header = 
 			ChunkHeader.createChunkHeader(version, data, offset);
+		// Sanity check
+		if(header.length < 0) {
+			throw new IllegalArgumentException("Found a chunk with a negative length, which isn't allowed");
+		}
+		
+		// How far up to look
 		int endOfDataPos = offset + header.getLength() + header.getSizeInBytes();
 		
 		// Check we have enough data, and tweak the header size

src/scratchpad/src/org/apache/poi/hdgf/chunks/ChunkHeader.java

@@ -45,6 +45,7 @@ public abstract class ChunkHeader {
 			ch.length   = (int)LittleEndian.getUInt(data, offset + 12);
 			ch.unknown2 = LittleEndian.getShort(data, offset + 16);
 			ch.unknown3 = (short)LittleEndian.getUnsignedByte(data, offset + 18);
+			
 			return ch;
 		} else if(documentVersion == 5) {
 			throw new RuntimeException("TODO");

src/scratchpad/testcases/org/apache/poi/hdgf/TestHDGFCore.java

@@ -25,11 +25,13 @@ import org.apache.poi.poifs.filesystem.POIFSFileSystem;
 import junit.framework.TestCase;
 
 public class TestHDGFCore extends TestCase {
-	POIFSFileSystem fs;
+	private POIFSFileSystem fs;
+	private String dirname;
+	private String filename;
 	
 	protected void setUp() throws Exception {
-		String dirname = System.getProperty("HDGF.testdata.path");
-		String filename = dirname + "/Test_Visio-Some_Random_Text.vsd";
+		dirname = System.getProperty("HDGF.testdata.path");
+		filename = dirname + "/Test_Visio-Some_Random_Text.vsd";
 		fs = new POIFSFileSystem(new FileInputStream(filename));
 	}
 	
@@ -59,4 +61,16 @@ public class TestHDGFCore extends TestCase {
 		assertNotNull(ps8.getPointedToStreams());
 		assertEquals(8, ps8.getPointedToStreams().length);
 	}
+	
+	/**
+	 * Tests that we can open a problematic file, that initially
+	 *  appears to have a negative chunk length
+	 */
+	public void DISABLEDtestNegativeChunkLength() throws Exception {
+		filename = dirname + "/NegativeChunkLength.vsd";
+		fs = new POIFSFileSystem(new FileInputStream(filename));
+		
+		HDGFDiagram hdgf = new HDGFDiagram(fs);
+		assertNotNull(hdgf);
+	}
 }