[[ CodeResources ]] Load from library mapping

montegoulding · montegoulding · commit 736c2ebd27e0 · 2017-12-13T21:24:45.000+11:00
This patch loads extension code resources from lbrary mappings
if they have been mapped by the IDE or standalone deploy params.
If there is no mapping then it falls back to try loading the library
by name followed by attempting to load the library using legacy
paths.

This patch also ensures that iOS device builds retain the engine
as the library handle rather than trying to load a library.
diff --git a/engine/src/exec-extension.cpp b/engine/src/exec-extension.cpp
@@ -229,64 +229,45 @@ void MCEngineLoadExtensionFromData(MCExecContext& ctxt, MCDataRef p_extension_da
 }
 
 // This is the callback given to libscript so that it can resolve the absolute
-// path of native code libraries used by foreign handlers in the module. At
-// the moment we use the resources path of the module, however it will need to be
-// changed to a separate location at some point with explicit declaration so that
-// iOS linkage and Android placement issues can be resolved.
-//
-// Currently it expects:
-//   <resources>
-//     code/
-//       mac/<name>.dylib
-//       linux-x86/<name>.so
-//       linux-x86_64/<name>.so
-//       win-x86/<name>.dll
-//
+// path of native code libraries used by foreign handlers in the module.
+
 static bool MCEngineLoadLibrary(MCScriptModuleRef p_module, MCStringRef p_name, MCSLibraryRef& r_library)
 {
-    // If the module has no resource path, then it has no code.
-    MCAutoStringRef t_resource_path;
-    if (!MCEngineLookupResourcePathForModule(p_module, Out(t_resource_path)))
-        return false;
-    
     MCSLibraryRef t_library = nullptr;
-    if (t_resource_path.IsSet() &&
-        !MCStringIsEmpty(*t_resource_path))
+    
+    // extension libraries should be mapped by the IDE or deploy params
+    MCAutoStringRef t_mapped_path;
+    if (MCdispatcher->fetchlibrarymapping(p_name, &t_mapped_path))
     {
-#if defined(__MAC__)
-        static const char *kLibraryFormat = "%@/code/mac/%@";
-#elif defined(__LINUX__) && defined(__32_BIT__)
-        static const char *kLibraryFormat = "%@/code/linux-x86/%@";
-#elif defined(__LINUX__) && defined(__64_BIT__)
-        static const char *kLibraryFormat = "%@/code/linux-x86_64/%@";
-#elif defined(__WINDOWS__)
-        static const char *kLibraryFormat = "%@/code/win-x86/%@";
-#elif defined(__ANDROID__)
-        static const char *kLibraryFormat = "%@/code/android-armv6/%@";
-#elif defined(__IOS__)
-        static const char *kLibraryFormat = "%@/code/ios/%@";
-#elif defined(__EMSCRIPTEN__)
-        static const char *kLibraryFormat = "%@/code/emscripten/%@";
-#else
-#error No default code path set for this platform
-#endif
-        MCAutoStringRef t_ext_path;
-        if (!MCStringFormat(&t_ext_path,
-                            kLibraryFormat,
-                            *t_resource_path,
-                            p_name))
+        MCAutoStringRef t_map_name;
+        if (!MCStringFormat(&t_map_name, "./%@", p_name))
+            return false;
+    
+        t_library = MCU_library_load(*t_map_name);
+        
+        // there was a mapping and it failed to load
+        if (t_library == nullptr)
         {
             return false;
         }
-        
-        t_library = MCU_library_load(*t_ext_path);
     }
     
+    // if not mapped then fallback to assuming a full path or a location
+    // supported by dlopen
     if (t_library == nullptr)
     {
         t_library = MCU_library_load(p_name);
     }
     
+#if defined(__IOS__)
+    // On iOS we fallback to the engine because with the exception of
+    // dynamic frameworks libraries will be static linked
+    if (t_library == nullptr)
+    {
+        t_library = MCValueRetain(MCScriptGetLibrary());
+    }
+#endif
+
     if (t_library == nullptr)
     {
         return false;
diff --git a/libscript/include/libscript/script.h b/libscript/include/libscript/script.h
@@ -53,6 +53,8 @@ bool MCScriptForEachBuiltinModule(MCScriptForEachBuiltinModuleCallback p_callbac
 
 void MCScriptSetLoadLibraryCallback(MCScriptLoadLibraryCallback callback);
 
+MCSLibraryRef MCScriptGetLibrary(void);
+
 void MCScriptSetWidgetBarrierCallbacks(MCScriptWidgetEnterCallback entry_callback, MCScriptWidgetLeaveCallback leave_callback);
 
 ////////////////////////////////////////////////////////////////////////////////
