Port shared code information from the wiki

Since the shared code now has special status with respect to
copyrights, port them into a more structured format in the source tree
and add a python function that parses and returns a dictionary with
the information.

I need this to exclude these files from the Contributed-by changes and
I reckon it would be useful to know these files for future tooling.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>

scripts/glibc_shared_code.py

@@ -0,0 +1,70 @@
+#!/usr/bin/python
+# Copyright (C) 2021 Free Software Foundation, Inc.
+# This file is part of the GNU C Library.
+#
+# The GNU C Library 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 2.1 of the License, or (at your option) any later version.
+#
+# The GNU C 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 the GNU C Library; if not, see
+# <https://www.gnu.org/licenses/>.
+
+def get_glibc_shared_code(path):
+    """ Get glibc shared code information from a file
+
+    The input file must have project names in their own line ending with a colon
+    and all shared files in the project on their own lines following the project
+    name.  Whitespaces are ignored.  Lines with # as the first non-whitespace
+    character are ignored.
+
+    Args:
+        path: The path to file containing shared code information.
+
+    Returns:
+        A dictionary with project names as key and lists of files as values.
+    """
+
+    projects = {}
+    with open(path, 'r') as f:
+        for line in f.readlines():
+            line = line.strip()
+            if len(line) == 0 or line[0] == '#':
+                continue
+            if line[-1] == ':':
+                cur = line[:-1]
+                projects[cur] = []
+            else:
+                projects[cur].append(line)
+
+    return projects
+
+# Function testing.
+import sys
+from os import EX_NOINPUT
+from os.path import exists
+from pprint import *
+
+if __name__ == '__main__':
+    if len(sys.argv) != 2:
+        print('Usage: %s <file name>' % sys.argv[0])
+        print('Run this script from the base glibc source directory')
+        sys.exit(EX_NOINPUT)
+
+    print('Testing get_glibc_shared_code with %s:\n' % sys.argv[1])
+    r = get_glibc_shared_code(sys.argv[1])
+    errors = False
+    for k in r.keys():
+        for f in r[k]:
+            if not exists(f):
+                print('%s does not exist' % f)
+                errors = True
+
+    if not errors:
+        pprint(r)