Handle malformed TOH/TOT resources more gracefully

Fixes issues caused by 2767993 and d6c39dc.
Argent77 · Apr 6, 2024 · 3f2507d · 3f2507d
1 parent d6c39dc
commit 3f2507d
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Showing 4 changed files with 45 additions and 12 deletions.
diff --git a/src/org/infinity/resource/sav/SavResource.java b/src/org/infinity/resource/sav/SavResource.java
@@ -120,9 +120,15 @@ public void actionPerformed(ActionEvent event) {
     } else if (buttonPanel.getControlByType(CTRL_DECOMPRESS) == event.getSource()) {
       decompressData(true);
     } else if (buttonPanel.getControlByType(CTRL_EDIT) == event.getSource()) {
-      ResourceEntry fileentry = entries.get(filelist.getSelectedIndex());
-      Resource res = ResourceFactory.getResource(fileentry);
-      new ViewFrame(panel.getTopLevelAncestor(), res);
+      try {
+        ResourceEntry fileentry = entries.get(filelist.getSelectedIndex());
+        Resource res = ResourceFactory.getResource(fileentry);
+        new ViewFrame(panel.getTopLevelAncestor(), res);
+      } catch (Exception e) {
+        e.printStackTrace();
+        JOptionPane.showMessageDialog(panel.getTopLevelAncestor(), "Could not open selected resource.", "Error",
+            JOptionPane.ERROR_MESSAGE);
+      }
     } else if (buttonPanel.getControlByType(ButtonPanel.Control.EXPORT_BUTTON) == event.getSource()) {
       ResourceFactory.exportResource(entry, panel.getTopLevelAncestor());
     } else if (buttonPanel.getControlByType(CTRL_DELETE) == event.getSource()) {
@@ -209,9 +215,15 @@ public JComponent makeViewer(ViewableContainer container) {
       @Override
       public void mouseClicked(MouseEvent event) {
         if (event.getClickCount() == 2) {
-          ResourceEntry fileentry = entries.get(filelist.getSelectedIndex());
-          Resource res = ResourceFactory.getResource(fileentry);
-          new ViewFrame(panel.getTopLevelAncestor(), res);
+          try {
+            ResourceEntry fileentry = entries.get(filelist.getSelectedIndex());
+            Resource res = ResourceFactory.getResource(fileentry);
+            new ViewFrame(panel.getTopLevelAncestor(), res);
+          } catch (Exception e) {
+            e.printStackTrace();
+            JOptionPane.showMessageDialog(panel.getTopLevelAncestor(), "Could not open selected resource.", "Error",
+                JOptionPane.ERROR_MESSAGE);
+          }
         }
       }
     });

diff --git a/src/org/infinity/resource/to/StringEntry.java b/src/org/infinity/resource/to/StringEntry.java
@@ -36,7 +36,7 @@ public int read(ByteBuffer buffer, int offset) throws Exception {
     addField(new HexNumber(buffer, offset, 4, TOT_STRING_OFFSET_FREE_REGION));
     addField(new HexNumber(buffer, offset + 4, 4, TOT_STRING_OFFSET_PREV_ENTRY));
     addField(new TextEdit(buffer, offset + 8, 512, TOT_STRING_TEXT));
-    addField(new HexNumber(buffer, offset + 520, 4, TOT_STRING_OFFSET_NEXT_ENTRY)); // Note: offset value is relative to structure base offset
+    addField(new HexNumber(buffer, offset + 520, 4, TOT_STRING_OFFSET_NEXT_ENTRY));
     return offset + 524;
   }
 }
diff --git a/src/org/infinity/resource/to/TohResource.java b/src/org/infinity/resource/to/TohResource.java
@@ -203,9 +203,6 @@ public static String getOverrideString(TohResource toh, TotResource tot, int str
                 if (se != null) {
                   retVal += se.getAttribute(StringEntry.TOT_STRING_TEXT).toString();
                   sofs = ((IsNumeric) se.getAttribute(StringEntry.TOT_STRING_OFFSET_NEXT_ENTRY)).getValue();
-                  if (sofs != -1) {
-                    sofs += se.getOffset();
-                  }
                 } else {
                   sofs = -1;
                 }

diff --git a/src/org/infinity/resource/to/TotResource.java b/src/org/infinity/resource/to/TotResource.java
@@ -76,14 +76,16 @@ public int read(ByteBuffer buffer, int offset) throws Exception {
           // looping through entries to consider split text segments
           StringEntry stringEntry = new StringEntry(this, buffer, offset, idx);
           while (stringEntry != null) {
+            if (!isStringEntryValid(stringEntry)) {
+              throw new Exception(String.format("Invalid string section found at offset 0x%x", stringEntry.getOffset()));
+            }
             offset = stringEntry.getEndOffset();
             addField(stringEntry);
             idx++;
             int ofsNextEntry = ((IsNumeric) stringEntry.getAttribute(StringEntry.TOT_STRING_OFFSET_NEXT_ENTRY))
                 .getValue();
             if (ofsNextEntry != -1) {
-              // Note: next entry offset is relative to structure base offset
-              stringEntry = new StringEntry(this, buffer, stringEntry.getOffset() + ofsNextEntry, idx);
+              stringEntry = new StringEntry(this, buffer, ofsNextEntry, idx);
             } else {
               stringEntry = null;
             }
@@ -111,6 +113,28 @@ public int read(ByteBuffer buffer, int offset) throws Exception {
     return endoffset;
   }
 
+  /**
+   * Analyzes a TOT {@code StringEntry} to determine whether the entry contains valid data.
+   *
+   * @param entry a {@link StringEntry}
+   * @return {@code true} if the entry is valid, {@code false} otherwise.
+   */
+  public static boolean isStringEntryValid(StringEntry entry) {
+    boolean retVal = false;
+
+    if (entry != null) {
+      try {
+        int ofsPrev = ((IsNumeric) entry.getAttribute(StringEntry.TOT_STRING_OFFSET_PREV_ENTRY)).getValue();
+        int ofsNext = ((IsNumeric) entry.getAttribute(StringEntry.TOT_STRING_OFFSET_NEXT_ENTRY)).getValue();
+        retVal = (ofsPrev == -1 && ofsNext == -1) || (ofsPrev != ofsNext);
+      } catch (Exception e) {
+        e.printStackTrace();
+      }
+    }
+
+    return retVal;
+  }
+
   /**
    * Attempts to find the associated TOH resource in the same directory as the current TOT resource and loads it if
    * available.