base: Add ability to generate SymbolTable by filtering SymbolType

This allows filtering out non function symbols.

Change-Id: I518c2842a6f04c4475240126ad64070a6de09df9
Signed-off-by: Hoa Nguyen <hn@hnpl.org>

src/base/loader/symtab.hh

@@ -176,6 +176,22 @@ class SymbolTable
         return filter(filt);
     }
 
+    /**
+     * Generate a new table by applying a filter that only accepts the symbols
+     * whose type matches the given symbol type.
+     *
+     * @param The type that must be matched.
+     * @return A new table, filtered by type.
+     */
+    SymbolTablePtr
+    filterBySymbolType(const Symbol::SymbolType& symbol_type) const
+    {
+        auto filt = [symbol_type](const Symbol &symbol) {
+            return symbol.type == symbol_type;
+        };
+        return filter(filt);
+    }
+
   public:
     typedef SymbolVector::iterator iterator;
     typedef SymbolVector::const_iterator const_iterator;
@@ -302,6 +318,17 @@ class SymbolTable
         return filterByBinding(Symbol::Binding::Weak);
     }
 
+    /**
+     * Generates a new symbol table containing only function symbols.
+     *
+     * @return The new table.
+     */
+    SymbolTablePtr
+    functionSymbols() const
+    {
+        return filterBySymbolType(Symbol::SymbolType::Function);
+    }
+
     /**
      * Serialize the table's contents.
      *