Forgot to add ReadContentInputStream

DataModel/src/org/sleuthkit/autopsy/datamodel/ReadContentInputStream.java

@@ -0,0 +1,90 @@
+/*
+ * Autopsy Forensic Browser
+ *
+ * Copyright 2011 Basis Technology Corp.
+ * Contact: carrier <at> sleuthkit <dot> org
+ *
+ * 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.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.sleuthkit.autopsy.datamodel;
+
+import java.io.IOException;
+import java.io.InputStream;
+import org.sleuthkit.datamodel.Content;
+import org.sleuthkit.datamodel.TskException;
+
+/**
+ * InputStream to read bytes from a Content object's data
+ */
+class ReadContentInputStream extends InputStream {
+
+    private long position;
+    private long length;
+    private Content content;
+
+    ReadContentInputStream(Content content) {
+        this.content = content;
+        this.position = 0;
+        this.length = content.getSize();
+    }
+
+    @Override
+    public int read() throws IOException {
+        byte[] buff = new byte[1];
+        return (read(buff) != -1) ? buff[0] : -1;
+    }
+
+    @Override
+    public int read(byte[] b) throws IOException {
+        return read(b, 0, b.length);
+    }
+
+    @Override
+    public int read(byte[] b, int off, int len) throws IOException {
+        
+        // must return 0 for zero-length arrays
+        if (b.length == 0) {
+            return 0;
+        }
+        
+        // will get an error from TSK if we try to read an empty file
+        if (this.length == 0) {
+            return -1;
+        }
+        
+        if (position < length) {
+            // data remains to be read
+            
+            int lenToRead = (int) Math.min(len, length - position);
+        
+            try {
+                byte[] buff = content.read(position, lenToRead);
+                int lenRead = buff.length;
+
+                if (lenRead == 0) {
+                    // TSK could not read the whole file, ending partway
+                    return -1;
+                } else {
+                    System.arraycopy(buff, 0, b, off, lenRead);
+                    position += lenRead;
+                    return lenRead;
+                }
+            } catch (TskException ex) {
+                throw new IOException(ex);
+            }
+        } else {
+            // at end of file
+            return -1;
+        }
+    }
+}