From 080fef17f3de297763b0762351d9835ea4f766e3 Mon Sep 17 00:00:00 2001
From: Brian Maloney <Beercow@users.noreply.github.com>
Date: Thu, 5 Mar 2026 12:32:00 -0600
Subject: [PATCH] Fix load time

---
 src/XstReader.Api/LTP.cs | 57 ++++++++++++++++++++++++++++++++--------
 src/XstReader.Api/NDB.cs | 15 ++++++-----
 2 files changed, 55 insertions(+), 17 deletions(-)

diff --git a/src/XstReader.Api/LTP.cs b/src/XstReader.Api/LTP.cs
index ef2bcdf..c4d6720 100644
--- a/src/XstReader.Api/LTP.cs
+++ b/src/XstReader.Api/LTP.cs
@@ -828,21 +828,44 @@ private List<HNDataBlock> ReadHeapOnNode(UInt64 dataBid)
         private byte[] GetBytesForHNID(List<HNDataBlock> blocks, BTree<Node> subNodeTree, HNID hnid)
         {
             byte[] buf = null;
-
-            if (hnid.hidType == EnidType.HID)
+        
+            try
             {
-                if (hnid.GetIndex(ndb.IsUnicode4K) != 0)
+                if (hnid.hidType == EnidType.HID)
+                {
+                    var index = hnid.GetIndex(ndb.IsUnicode4K);
+        
+                    if (index > 0)
+                    {
+                        var blockIndex = hnid.HID.GetBlockIndex(ndb.IsUnicode4K);
+        
+                        // Validate block index
+                        if (blockIndex >= 0 && blockIndex < blocks.Count)
+                        {
+                            var size = HidSize(blocks, hnid.HID);
+        
+                            if (size > 0)
+                            {
+                                buf = MapArray<byte>(blocks, hnid.HID, size);
+                            }
+                        }
+                    }
+                }
+                else if (hnid.nidType == EnidType.LTP)
                 {
-                    buf = MapArray<byte>(blocks, hnid.HID, HidSize(blocks, hnid.HID));
+                    buf = ndb.ReadSubNodeDataBlock(subNodeTree, hnid.NID);
+                }
+                else
+                {
+                    throw new XstException("Data storage style not implemented");
                 }
             }
-            else if (hnid.nidType == EnidType.LTP)
+            catch (IndexOutOfRangeException)
             {
-                buf = ndb.ReadSubNodeDataBlock(subNodeTree, hnid.NID);
+                // Corrupt heap allocation or bad HID reference
+                return null;
             }
-            else
-                throw new XstException("Data storage style not implemented");
-
+        
             return buf;
         }
 
@@ -851,9 +874,21 @@ private byte[] GetBytesForHNID(List<HNDataBlock> blocks, BTree<Node> subNodeTree
         private int HidSize(List<HNDataBlock> blocks, HID hid)
         {
             var index = hid.GetIndex(ndb.IsUnicode4K);
-            if (index == 0) // Check for empty
+            if (index <= 0)
                 return 0;
-            var b = blocks[hid.GetBlockIndex(ndb.IsUnicode4K)];
+        
+            var blockIndex = hid.GetBlockIndex(ndb.IsUnicode4K);
+        
+            // Validate block index
+            if (blockIndex < 0 || blockIndex >= blocks.Count)
+                return 0;
+        
+            var b = blocks[blockIndex];
+        
+            // Validate allocation index
+            if (index >= b.rgibAlloc.Length || index - 1 < 0)
+                return 0;
+        
             return b.rgibAlloc[index] - b.rgibAlloc[index - 1];
         }
 
diff --git a/src/XstReader.Api/NDB.cs b/src/XstReader.Api/NDB.cs
index cbc54a4..3881e11 100644
--- a/src/XstReader.Api/NDB.cs
+++ b/src/XstReader.Api/NDB.cs
@@ -536,13 +536,16 @@ private byte[] ReadAndDecompress(DataRef rb, out int read, byte[] buffer = null,
                     {
                         if (buffer == null)
                             buffer = new byte[rb.InflatedLength];
-
-                        var writable = new MemoryStream(buffer, offset, rb.InflatedLength, true);
-                        decompressionStream.CopyTo(writable);
-
-                        if (writable.Position != writable.Length)
+                        int curPos = 0;
+                        int buffLen = buffer.Length;
+                        int batchSize = buffLen > 65536 ? 16384 : 4096;
+                        while (curPos < buffer.Length)
                         {
-                            throw new EndOfStreamException();
+                            int count = Math.Min(batchSize, buffLen - curPos);
+                            int bytesRead = decompressionStream.Read(buffer, curPos, count);
+                            if (bytesRead == 0)
+                                throw new EndOfStreamException();   // restore safety;
+                            curPos += bytesRead;
                         }
                     }
                     read = rb.InflatedLength;