From 95d165832448798ed3391442f9d077bc89921afb Mon Sep 17 00:00:00 2001
From: Matt Nadareski <mnadareski@outlook.com>
Date: Fri, 4 Nov 2022 16:04:01 -0700
Subject: [PATCH] Add LE/LX debug information

---
 .../LinearExecutable/DebugInformation.cs      | 36 +++++++++++++++++++
 BurnOutSharp.Models/LinearExecutable/Enums.cs | 23 ++++++++++++
 .../LinearExecutable/Executable.cs            |  6 +++-
 3 files changed, 64 insertions(+), 1 deletion(-)
 create mode 100644 BurnOutSharp.Models/LinearExecutable/DebugInformation.cs

diff --git a/BurnOutSharp.Models/LinearExecutable/DebugInformation.cs b/BurnOutSharp.Models/LinearExecutable/DebugInformation.cs
new file mode 100644
index 00000000..32ce5070
--- /dev/null
+++ b/BurnOutSharp.Models/LinearExecutable/DebugInformation.cs
@@ -0,0 +1,36 @@
+using System.Runtime.InteropServices;
+
+namespace BurnOutSharp.Models.LinearExecutable
+{
+    /// <summary>
+    /// The debug information is defined by the debugger and is not controlled by
+    /// the linear EXE format or linker. The only data defined by the linear EXE
+    /// format relative to the debug information is it's offset in the EXE file and
+    /// length in bytes as defined in the linear EXE header.
+    /// 
+    /// To support multiple debuggers the first word of the debug information is a
+    /// type field which determines the format of the debug information.
+    /// </summary>
+    /// <see href="https://faydoc.tripod.com/formats/exe-LE.htm"/>
+    /// <see href="http://www.edm2.com/index.php/LX_-_Linear_eXecutable_Module_Format_Description"/>
+    [StructLayout(LayoutKind.Sequential)]
+    public class DebugInformation
+    {
+        /// <summary>
+        /// The signature consists of a string of three (3) ASCII characters: "NB0"
+        /// </summary>
+        public byte[] Signature;
+
+        /// <summary>
+        /// This defines the type of debugger data that exists in the remainder of the
+        /// debug information.
+        /// </summary>
+        public DebugFormatType FormatType;
+
+        // DEBUGGER DATA = Debugger specific data.
+        // The format of the debugger data is defined by the debugger that is being used.
+        // The values defined for the type field are not enforced by the system. It is
+        // the responsibility of the linker or debugging tools to follow the convention
+        // for the type field that is defined here. 
+    }
+}
diff --git a/BurnOutSharp.Models/LinearExecutable/Enums.cs b/BurnOutSharp.Models/LinearExecutable/Enums.cs
index 7c5ae0fa..f4d4cf69 100644
--- a/BurnOutSharp.Models/LinearExecutable/Enums.cs
+++ b/BurnOutSharp.Models/LinearExecutable/Enums.cs
@@ -102,6 +102,29 @@ namespace BurnOutSharp.Models.LinearExecutable
         MIPSMarkIII = 0x42,
     }
 
+    public enum DebugFormatType : byte
+    {
+        /// <summary>
+        /// 32-bit CodeView debugger format.
+        /// </summary>
+        CodeView32Bit = 0x00,
+
+        /// <summary>
+        /// AIX debugger format.
+        /// </summary>
+        AIXDebugger = 0x01,
+
+        /// <summary>
+        /// 16-bit CodeView debugger format.
+        /// </summary>
+        CodeView16Bit = 0x02,
+
+        /// <summary>
+        /// 32-bit OS/2 PM debugger (IBM) format.
+        /// </summary>
+        OS2PM32Bit = 0x04,
+    }
+
     public enum DirectiveNumber : ushort
     {
         /// <summary>
diff --git a/BurnOutSharp.Models/LinearExecutable/Executable.cs b/BurnOutSharp.Models/LinearExecutable/Executable.cs
index e1d62628..84d09c59 100644
--- a/BurnOutSharp.Models/LinearExecutable/Executable.cs
+++ b/BurnOutSharp.Models/LinearExecutable/Executable.cs
@@ -82,6 +82,10 @@ namespace BurnOutSharp.Models.LinearExecutable
         public NonResidentNameTableEntry[] NonResidentNameTable { get; set; }
 
         // TODO: Non-resident directives data
-        // TODO: Debug Info
+
+        /// <summary>
+        /// Debug information
+        /// </summary>
+        public DebugInformation DebugInformation { get; set; }
     }
 }