Initial LE format (Linear executable)

Author: yetmorecode

src/yetmorecode/format/exception/InvalidHeaderException.java

@@ -0,0 +1,9 @@
+package yetmorecode.format.exception;
+
+/**
+ * An exception class to handle encountering
+ * invalid LX/LE Headers.
+ */
+public class InvalidHeaderException extends Exception {
+	private static final long serialVersionUID = 1L;
+}

src/yetmorecode/format/lx/LeObjectPageTableEntry.java

@@ -0,0 +1,119 @@
+package yetmorecode.format.lx;
+
+/**
+ * The Object page table provides information about a logical page in an object. 
+ * 
+ * A logical page may be an enumerated page, a pseudo page or an iterated page. 
+ * The structure of the object page table in conjunction with the structure of the object table 
+ * allows for efficient access of a page when a page fault occurs, while still allowing the 
+ * physical page data to be located in the preload page, demand load page or 
+ * iterated data page sections in the linear EXE module. 
+ * 
+ * The logical page entries in the Object Page Table are numbered starting from one. 
+ * 
+ * The Object Page Table is parallel to the Fixup Page Table as they are both indexed by the logical page number.
+ * 
+ * Each Object Page Table entry has the following format:
+ * 
+ *    32                                  8 7          0
+ *     +-----+-----+-----+-----+-----+-----+-----+-----+
+ * 00h |             PAGE NUMBER           |   FLAGS   |
+ *     +-----+-----+-----+-----+-----+-----+-----+-----+
+ *     
+ * @author https://github.com/yetmorecode
+ *
+ */
+public class LeObjectPageTableEntry implements ObjectPageTableEntry {
+	/**
+	 * Size of an LE object page table entry
+	 */
+	public final static int SIZE = 0x4;
+	
+	/**
+	 * PAGE Number = 24bit Offset to the page data in the EXE file.
+	 * 
+	 * This field, when bit shifted left by the PAGE OFFSET SHIFT from the module header,
+	 * specifies the offset from the beginning of the Preload Page section of the physical
+	 * page data in the EXE file that corresponds to this logical page entry. The page data
+	 * may reside in the Preload Pages, Demand Load Pages or the Iterated Data Pages
+	 * sections.
+	 * 
+	 * A page might not start at the next available alignment boundary. Extra padding is
+	 * acceptable between pages as long as each page starts on an alignment boundary.
+	 * 
+	 * For example, several alignment boundaries may be skipped in order to start a
+	 * frequently accessed page on a sector boundary.
+	 * If the FLAGS field specifies that this is a Zero-Filled page then the PAGE DATA
+	 * OFFSET field will contain a 0.
+	 * 
+	 * If the logical page is specified as an iterated data page, as indicated by the FLAGS
+	 * field, then this field specifies the offset into the Iterated Data Pages section.
+	 * The logical page number (Object Page Table index), is used to index the Fixup Page
+	 * Table to find any fixups associated with the logical page.
+	 * 
+	 */
+	public int dataOffset;
+	
+	/**
+	 * 00h = Legal Physical Page in the module (Offset from Preload Page Section).
+	 */
+	public final static short FLAG_LEGAL = 0x0;
+	
+	/**
+	 * 01h = Iterated Data Page (Offset from Iterated Data Pages Section).
+	 */
+	public final static short FLAG_ITERATED = 0x1;
+	
+	/**
+	 * 02h = Invalid Page (zero).
+	 */
+	public final static short FLAG_INVALID = 0x2;
+	
+	/**
+	 * 03h = Zero Filled Page (zero).
+	 */
+	public final static short FLAG_ZERO = 0x3;
+	
+	/**
+	 * 04h = Range of Pages.
+	 */
+	public final static short FLAG_RANGE = 0x4;
+	
+	/**
+	 * 05h = Compressed Page (Offset from Preload Pages Section).
+	 */
+	public final static short FLAG_COMPRESSED = 0x5;
+	
+	/**
+	 * FLAGS = DW Attributes specifying characteristics of this logical page.
+	 * 
+	 * The bit definitions for this word field follow,
+	 * 00h = Legal Physical Page in the module (Offset from Preload Page Section).
+	 * 01h = Iterated Data Page (Offset from Iterated Data Pages Section).
+	 * 02h = Invalid Page (zero).
+	 * 03h = Zero Filled Page (zero).
+	 * 04h = Range of Pages.
+	 * 05h = Compressed Page (Offset from Preload Pages Section).
+	 */
+	public byte flags;
+
+	@Override
+	public int getOffset() {
+		return dataOffset;
+	}
+
+	@Override
+	public short getSize() {
+		return 0;
+	}
+
+	@Override
+	public short getFlags() {
+		// Prevent java sign extension issues
+		if (flags < 0) {
+			return (short) (flags + 0x100);
+		}
+		return flags;
+	}
+
+}

src/yetmorecode/format/lx/LxExecutable.java

@@ -0,0 +1,37 @@
+package yetmorecode.format.lx;
+
+import java.util.ArrayList;
+
+import yetmorecode.format.mz.MzHeader;
+
+public class LxExecutable {
+	/**
+	 * Old-style MS-DOS header (optional)
+	 */
+	public MzHeader dosHeader = new MzHeader();
+	
+	/**
+	 * LX/LE/LC header
+	 */
+	public LxHeader header = new LxHeader();
+	
+	/**
+	 * Object table
+	 */
+	public ArrayList<ObjectTableEntry> objectTable = new ArrayList<>();
+	
+	/**
+	 * The object page table (mapping page numbers to file offsets)
+	 */
+	public ArrayList<ObjectPageTableEntry> objectPageTable = new ArrayList<>();
+	
+	/**
+	 * The fixup record table
+	 */
+	public ArrayList<ArrayList<LxFixupRecord>> fixupRecordTable = new ArrayList<>();
+	
+	/**
+	 * The actual data pages
+	 */
+	public ArrayList<byte[]> pages = new ArrayList<>();
+}