feat: ContextBuilder::release to get owned underlying FFI context builder

CMakeLists.txt

@@ -14,7 +14,7 @@
 cmake_minimum_required(VERSION 3.27)
 
 # This is the current version of this C++ project
-project(c2pa-c VERSION 0.19.2)
+project(c2pa-c VERSION 0.20.0)
 
 # Set the version of the c2pa_rs library used
 set(C2PA_VERSION "0.78.6")

include/c2pa.hpp

@@ -317,9 +317,12 @@ namespace c2pa
             /// @note This consumes the builder. After calling this, is_valid() returns false.
             [[nodiscard]] Context create_context();
 
-            /// @brief Get the underlying C2paContextBuilder pointer.
+            /// @brief Release ownership of the underlying C2paContextBuilder pointer.
+            ///        After this call, the ContextBuilder no longer owns the pointer
+            ///        and is_valid() returns false. The caller is responsible for managing
+            ///        the lifetime of the returned pointer.
             /// @return Pointer to the C2paContextBuilder object, or nullptr if moved from.
-            C2paContextBuilder* c2pa_context_builder() const noexcept;
+            C2paContextBuilder* release() noexcept;
 
         private:
             C2paContextBuilder* context_builder;

src/c2pa_context.cpp

@@ -154,8 +154,8 @@ namespace c2pa
         return *this;
     }
 
-    C2paContextBuilder* Context::ContextBuilder::c2pa_context_builder() const noexcept {
-        return context_builder;
+    C2paContextBuilder* Context::ContextBuilder::release() noexcept {
+        return std::exchange(context_builder, nullptr);
     }
 
     Context Context::ContextBuilder::create_context() {