From f3a1293e4650b452125bb44f943c4b06d7a89743 Mon Sep 17 00:00:00 2001
From: Sean <skasun@gmail.com>
Date: Tue, 21 May 2024 21:26:08 -0700
Subject: [PATCH] support jumptable segments

---
 src/omf.cc | 17 +++++++++++++++++
 src/omf.h  |  1 +
 2 files changed, 18 insertions(+)

diff --git a/src/omf.cc b/src/omf.cc
index aed2a7b..0e024ce 100644
--- a/src/omf.cc
+++ b/src/omf.cc
@@ -32,6 +32,9 @@ bool Segment::isDPS() {
   return (kind & 0x1f) == 0x12;
 }
 
+bool Segment::isJump() {
+  return (kind & 0x1f) == 0x02;
+}
 
 bool OMF::load(const char *filename, uint32_t org) {
   handle = TheHandle::createFromFile(filename);
@@ -382,6 +385,20 @@ bool OMF::relocSegments() {
           break;
       }
     }
+    if (seg.isJump()) {  // patch jumptable
+      for (int i = 8; i < seg.length; i += 14) {
+        uint16_t segnum = data[i + 4] | (data[i + 5] << 8);
+        int32_t subOffset = data[i + 6] | (data[i + 7] << 8) |
+            (data[i + 8] << 16) | (data[i + 9] << 24);
+        for (auto &sub : segments) {
+          if (sub.segnum == segnum) {
+            subOffset += sub.mapped;
+            break;
+          }
+        }
+        patch(data, i + 11, 3, subOffset);
+      }
+    }
     seg.data = TheHandle::createFromArray(data);
   }
   return true;
diff --git a/src/omf.h b/src/omf.h
index 9ea0229..bfbf911 100644
--- a/src/omf.h
+++ b/src/omf.h
@@ -26,6 +26,7 @@ struct Segment {
   bool map(std::vector<uint32_t> &memory, bool force);
   void initDPS();
   bool isDPS();
+  bool isJump();
 };
 
 class OMF {