_loader/loader: cythonize valid_chars_name

- Create a new _loader/utils.pyx cython module for functions cythonized
in the loader module.

- Move valid_chars_name from loader to utils and cythonize.

This function is called extensively, and easy to extract

2 files changed, 54 insertions, 31 deletions

diff --git a/src/buildstream/_loader/_loader.pyx b/src/buildstream/_loader/_loader.pyx
new file mode 100644
index 000000000..258a34ab7
--- /dev/null
+++ b/src/buildstream/_loader/_loader.pyx
@@ -0,0 +1,52 @@
+#
+#  Copyright (C) 2019 Bloomberg L.P.
+#
+#  This program is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU Lesser General Public
+#  License as published by the Free Software Foundation; either
+#  version 2 of the License, or (at your option) any later version.
+#
+#  This library is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU
+#  Lesser General Public License for more details.
+#
+#  You should have received a copy of the GNU Lesser General Public
+#  License along with this library. If not, see <http://www.gnu.org/licenses/>.
+#
+#  Authors:
+#        Benjamin Schubert <bschubert@bloomberg.net>
+#
+
+
+# Check if given filename containers valid characters.
+#
+# Args:
+#    name (str): Name of the file
+#
+# Returns:
+#    (bool): True if all characters are valid, False otherwise.
+#
+def valid_chars_name(str name):
+    cdef int char_value
+    cdef int forbidden_char
+
+    for char_value in name:
+        # 0-31 are control chars, 127 is DEL, and >127 means non-ASCII
+        if char_value <= 31 or char_value >= 127:
+            return False
+
+        # Disallow characters that are invalid on Windows. The list can be
+        # found at https://docs.microsoft.com/en-us/windows/desktop/FileIO/naming-a-file
+        #
+        # Note that although : (colon) is not allowed, we do not raise
+        # warnings because of that, since we use it as a separator for
+        # junctioned elements.
+        #
+        # We also do not raise warnings on slashes since they are used as
+        # path separators.
+        for forbidden_char in '<>"|?*':
+            if char_value == forbidden_char:
+                return False
+
+    return True
diff --git a/src/buildstream/_loader/loader.py b/src/buildstream/_loader/loader.py
index 752883d96..5435e0d41 100644
--- a/src/buildstream/_loader/loader.py
+++ b/src/buildstream/_loader/loader.py
@@ -27,6 +27,7 @@ from ..element import Element
 from .._profile import Topics, PROFILER
 from .._includes import Includes
 
+from ._loader import valid_chars_name
 from .types import Symbol
 from .loadelement import LoadElement, _extract_depends_from_node
 from .metaelement import MetaElement
@@ -759,7 +760,7 @@ class Loader():
         for filename in elements:
             if not filename.endswith(".bst"):
                 invalid_elements[CoreWarnings.BAD_ELEMENT_SUFFIX].append(filename)
-            if not self._valid_chars_name(filename):
+            if not valid_chars_name(filename):
                 invalid_elements[CoreWarnings.BAD_CHARACTERS_IN_NAME].append(filename)
 
         if invalid_elements[CoreWarnings.BAD_ELEMENT_SUFFIX]:
@@ -771,33 +772,3 @@ class Loader():
             self._warn("Target elements '{}' have invalid characerts in their name."
                        .format(invalid_elements[CoreWarnings.BAD_CHARACTERS_IN_NAME]),
                        warning_token=CoreWarnings.BAD_CHARACTERS_IN_NAME)
-
-    # Check if given filename containers valid characters.
-    #
-    # Args:
-    #    name (str): Name of the file
-    #
-    # Returns:
-    #    (bool): True if all characters are valid, False otherwise.
-    #
-    def _valid_chars_name(self, name):
-        for char in name:
-            char_val = ord(char)
-
-            # 0-31 are control chars, 127 is DEL, and >127 means non-ASCII
-            if char_val <= 31 or char_val >= 127:
-                return False
-
-            # Disallow characters that are invalid on Windows. The list can be
-            # found at https://docs.microsoft.com/en-us/windows/desktop/FileIO/naming-a-file
-            #
-            # Note that although : (colon) is not allowed, we do not raise
-            # warnings because of that, since we use it as a separator for
-            # junctioned elements.
-            #
-            # We also do not raise warnings on slashes since they are used as
-            # path separators.
-            if char in r'<>"|?*':
-                return False
-
-        return True