remove recursion from the ApplyStateTable::read and add flat call ApplyStateTable::readLocal

Signed-off-by: Pratik Mankawde <3397372+pratikmankawde@users.noreply.github.com>

Author: pratikmankawde

include/xrpl/ledger/detail/ApplyStateTable.h

@@ -64,6 +64,11 @@ class ApplyStateTable
     std::shared_ptr<SLE const>
     read(ReadView const& base, Keylet const& k) const;
 
+    /** Check only local items without delegating to base.
+        Returns std::nullopt if key not found locally. */
+    std::optional<std::shared_ptr<SLE const>>
+    readLocal(Keylet const& k) const;
+
     std::shared_ptr<SLE>
     peek(ReadView const& base, Keylet const& k);
 

src/libxrpl/ledger/ApplyStateTable.cpp

@@ -330,6 +330,28 @@ ApplyStateTable::read(ReadView const& base, Keylet const& k) const
     return sle;
 }
 
+std::optional<std::shared_ptr<SLE const>>
+ApplyStateTable::readLocal(Keylet const& k) const
+{
+    auto const iter = items_.find(k.key);
+    if (iter == items_.end())
+        return std::nullopt;
+    auto const& item = iter->second;
+    auto const& sle = item.second;
+    switch (item.first)
+    {
+        case Action::erase:
+            return nullptr;
+        case Action::cache:
+        case Action::insert:
+        case Action::modify:
+            break;
+    };
+    if (!k.check(*sle))
+        return nullptr;
+    return sle;
+}
+
 std::shared_ptr<SLE>
 ApplyStateTable::peek(ReadView const& base, Keylet const& k)
 {

src/libxrpl/ledger/ApplyViewBase.cpp

@@ -48,7 +48,20 @@ ApplyViewBase::succ(key_type const& key, std::optional<key_type> const& last) co
 std::shared_ptr<SLE const>
 ApplyViewBase::read(Keylet const& k) const
 {
-    return items_.read(*base_, k);
+    // Iteratively walk up the chain of ApplyViewBase layers
+    // instead of recursing through items_.read(*base_, k).
+    auto const* current = this;
+    while (current)
+    {
+        if (auto result = current->items_.readLocal(k))
+            return *result;
+
+        // Check if the base is another ApplyViewBase layer
+        auto const* next = dynamic_cast<ApplyViewBase const*>(current->base_);
+        if (!next)
+            return current->base_->read(k);
+        current = next;
+    }
 }
 
 auto