mm_mem_io_c: get_buffer() for r/w instances

src/common/mm_io.cpp

@@ -819,6 +819,14 @@ mm_mem_io_c::eof() {
   return m_pos >= m_mem_size;
 }
 
+unsigned char *
+mm_mem_io_c::get_buffer()
+  const {
+  if (m_read_only)
+    throw mtx::invalid_parameter_x();
+  return m_mem;
+}
+
 unsigned char *
 mm_mem_io_c::get_and_lock_buffer() {
   m_free_mem = false;

src/common/mm_io.h

@@ -236,6 +236,7 @@ public:
     m_file_name = file_name;
   }
 
+  virtual unsigned char *get_buffer() const;
   virtual unsigned char *get_and_lock_buffer();
   virtual std::string get_content() const;