Fixed exporters to support features

Unified how resources are loaded into the configuration system
(Config.load_resources) and applied it to build_api and exporters

tools/build_api.py

@@ -214,23 +214,8 @@ def build_project(src_path, build_path, target, toolchain_name,
             else:
                 resources.inc_dirs.append(inc_dirs)
 
-        # Update configuration files until added features creates no changes
+        # Load resources into the config system which might expand/modify resources based on config data
-        prev_features = set()
+        resources = config.load_resources(resources)
-        while True:
-            # Update the configuration with any .json files found while scanning
-            config.add_config_files(resources.json_files)
-
-            # Add features while we find new ones
-            features = config.get_features()
-            if features == prev_features:
-                break
-
-            for feature in features:
-                if feature in resources.features:
-                    resources.add(resources.features[feature])
-
-            prev_features = features
-        config.validate_config()
 
         # Set the toolchain's config header with the config data
         toolchain.set_config_header_content(config.get_config_data_header())
@@ -373,23 +358,8 @@ def build_library(src_paths, build_path, target, toolchain_name,
         # Handle configuration
         config = Config(target)
 
-        # Update configuration files until added features creates no changes
+        # Load resources into the config system which might expand/modify resources based on config data
-        prev_features = set()
+        resources = config.load_resources(resources)
-        while True:
-            # Update the configuration with any .json files found while scanning
-            config.add_config_files(resources.json_files)
-
-            # Add features while we find new ones
-            features = config.get_features()
-            if features == prev_features:
-                break
-
-            for feature in features:
-                if feature in resources.features:
-                    resources.add(resources.features[feature])
-
-            prev_features = features
-        config.validate_config()
 
         # Set the toolchain's config header with the config data
         toolchain.set_config_header_content(config.get_config_data_header())

tools/config.py

@@ -396,6 +396,30 @@ class Config:
             raise self.config_errors[0]
         return True
 
+        
+    # Loads configuration data from resources. Also expands resources based on defined features settings
+    def load_resources(self, resources):
+        # Update configuration files until added features creates no changes
+        prev_features = set()
+        while True:
+            # Add/update the configuration with any .json files found while scanning
+            self.add_config_files(resources.json_files)
+
+            # Add features while we find new ones
+            features = self.get_features()
+            if features == prev_features:
+                break
+
+            for feature in features:
+                if feature in resources.features:
+                    resources.add(resources.features[feature])
+
+            prev_features = features
+        self.validate_config()
+
+        return resources
+        
+
     # Return the configuration data converted to the content of a C header file,
     # meant to be included to a C/C++ file. The content is returned as a string.
     # If 'fname' is given, the content is also written to the file called "fname".

tools/export/exporters.py

@@ -129,7 +129,7 @@ class Exporter(object):
         # Copy only the file for the required target and toolchain
         lib_builds = []
         # Create the configuration object
-        cfg = Config(self.target, prj_paths)
+        config = Config(self.target, prj_paths)
         for src in ['lib', 'src']:
             resources = reduce(add, [self.__scan_and_copy(join(path, src), trg_path) for path in prj_paths])
             lib_builds.extend(resources.lib_builds)
@@ -155,15 +155,20 @@ class Exporter(object):
 
         if not relative:
             # Final scan of the actual exported resources
-            self.resources = self.toolchain.scan_resources(trg_path)
+            resources = self.toolchain.scan_resources(trg_path)
-            self.resources.relative_to(trg_path, self.DOT_IN_RELATIVE_PATH)
+            resources.relative_to(trg_path, self.DOT_IN_RELATIVE_PATH)
         else:
             # use the prj_dir (source, not destination)
-            self.resources = reduce(add, [self.toolchain.scan_resources(path) for path in prj_paths])
+            resources = self.toolchain.scan_resources(prj_paths[0])
-        # Add all JSON files discovered during scanning to the configuration object
+            for path in prj_paths[1:]:
-        cfg.add_config_files(self.resources.json_files)
+                resources.add(toolchain.scan_resources(path))
-        # Get data from the configuration system
+
-        self.config_macros = cfg.get_config_data_macros()
+        # Loads the resources into the config system which might expand/modify resources based on config data
+        self.resources = config.load_resources(resources)
+
+        # And add the configuration macros to the toolchain
+        self.config_macros = config.get_config_data_macros()
+                
         # Check the existence of a binary build of the mbed library for the desired target
         # This prevents exporting the mbed libraries from source
         # if not self.toolchain.mbed_libs: