1 files changed, 59 insertions, 0 deletions
diff --git a/Documentation/sphinx/load_config.py b/Documentation/sphinx/load_config.py
new file mode 100644
index 0000000000..8b416bfd75
--- /dev/null
+++ b/Documentation/sphinx/load_config.py
@@ -0,0 +1,59 @@
+# -*- coding: utf-8; mode: python -*-
+# pylint: disable=R0903, C0330, R0914, R0912, E0401
+
+import os
+import sys
+from sphinx.util.osutil import fs_encoding
+
+# ------------------------------------------------------------------------------
+def loadConfig(namespace):
+# ------------------------------------------------------------------------------
+
+    u"""Load an additional configuration file into *namespace*.
+
+    The name of the configuration file is taken from the environment
+    ``SPHINX_CONF``. The external configuration file extends (or overwrites) the
+    configuration values from the origin ``conf.py``.  With this you are able to
+    maintain *build themes*.  """
+
+    config_file = os.environ.get("SPHINX_CONF", None)
+    if (config_file is not None
+        and os.path.normpath(namespace["__file__"]) != os.path.normpath(config_file) ):
+        config_file = os.path.abspath(config_file)
+
+        # Let's avoid one conf.py file just due to latex_documents
+        start = config_file.find('Documentation/')
+        if start >= 0:
+            start = config_file.find('/', start + 1)
+
+        end = config_file.rfind('/')
+        if start >= 0 and end > 0:
+            dir = config_file[start + 1:end]
+
+            print("source directory: %s" % dir)
+            new_latex_docs = []
+            latex_documents = namespace['latex_documents']
+
+            for l in latex_documents:
+                if l[0].find(dir + '/') == 0:
+                    has = True
+                    fn = l[0][len(dir) + 1:]
+                    new_latex_docs.append((fn, l[1], l[2], l[3], l[4]))
+                    break
+
+            namespace['latex_documents'] = new_latex_docs
+
+        # If there is an extra conf.py file, load it
+        if os.path.isfile(config_file):
+            sys.stdout.write("load additional sphinx-config: %s\n" % config_file)
+            config = namespace.copy()
+            config['__file__'] = config_file
+            with open(config_file, 'rb') as f:
+                code = compile(f.read(), fs_encoding, 'exec')
+                exec(code, config)
+            del config['__file__']
+            namespace.update(config)
+        else:
+            config = namespace.copy()
+            config['tags'].add("subproject")
+            namespace.update(config)