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diff --git a/scripts/gitlog_to_changelog.py b/scripts/gitlog_to_changelog.py
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+#!/usr/bin/python3
+# Main VCSToChangeLog script.
+# Copyright (C) 2019 Free Software Foundation, Inc.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program 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 General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+''' Generate a ChangeLog style output based on a VCS log.
+
+This script takes two revisions as input and generates a ChangeLog style output
+for all revisions between the two revisions.
+
+This script is intended to be executed from the project parent directory.
+
+The vcs_to_changelog directory has a file vcstocl_quirks.py that defines a
+function called get_project_quirks that returns a object of class type
+ProjectQuirks or a subclass of the same.  The definition of the ProjectQuirks
+class is below and it specifies the properties that the project must set to
+ensure correct parsing of its contents.
+
+Among other things, ProjectQurks specifies the VCS to read from; the default is
+assumed to be git.  The script then studies the VCS log and for each change,
+list out the nature of changes in the constituent files.
+
+Each file type may have parser frontends that can read files and construct
+objects that may be compared to determine the minimal changes that occured in
+each revision.  For files that do not have parsers, we may only know the nature
+of changes at the top level depending on the information that the VCS stores.
+
+The parser frontend must have a compare() method that takes the old and new
+files as arrays of strings and prints the output in ChangeLog format.
+
+Currently implemented VCS:
+
+    git
+
+Currently implemented frontends:
+
+    C
+'''
+import sys
+import os
+import re
+import argparse
+from vcs_to_changelog.misc_util import *
+from vcs_to_changelog import frontend_c
+from vcs_to_changelog.vcs_git import *
+
+debug = DebugUtil(False)
+
+class ProjectQuirks:
+    # This is a list of regex substitutions for C/C++ macros that are known to
+    # break parsing of the C programs.  Each member of this list is a dict with
+    # the key 'orig' having the regex and 'sub' having the substitution of the
+    # regex.
+    MACRO_QUIRKS = []
+
+    # This is a list of macro definitions that are extensively used and are
+    # known to break parsing due to some characteristic, mainly the lack of a
+    # semicolon at the end.
+    C_MACROS = []
+
+    # The repo type, defaults to git.
+    repo = 'git'
+
+    # List of files to ignore either because they are not needed (such as the
+    # ChangeLog) or because they are non-parseable.  For example, glibc has a
+    # header file that is only assembly code, which breaks the C parser.
+    IGNORE_LIST = ['ChangeLog']
+
+
+# Load quirks file.  We assume that the script is run from the top level source
+# directory.
+sys.path.append('/'.join([os.getcwd(), 'scripts', 'vcs_to_changelog']))
+try:
+    from vcstocl_quirks import *
+    project_quirks = get_project_quirks(debug)
+except:
+    project_quirks = ProjectQuirks()
+
+def analyze_diff(filename, oldfile, newfile, frontends):
+    ''' Parse the output of the old and new files and print the difference.
+
+    For input files OLDFILE and NEWFILE with name FILENAME, generate reduced
+    trees for them and compare them.  We limit our comparison to only C source
+    files.
+    '''
+    name, ext = os.path.splitext(filename)
+
+    if not ext in frontends.keys():
+        return None
+    else:
+        frontend = frontends[ext]
+        frontend.compare(oldfile, newfile)
+
+
+def main(repo, frontends, refs):
+    ''' ChangeLog Generator Entry Point.
+    '''
+    commits = repo.list_commits(args.refs)
+    for commit in commits:
+        repo.list_changes(commit, frontends)
+
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser()
+
+    parser.add_argument('refs', metavar='ref', type=str, nargs=2,
+                     help='Refs to print ChangeLog entries between')
+
+    parser.add_argument('-d', '--debug', required=False, action='store_true',
+                     help='Run the file parser debugger.')
+
+    args = parser.parse_args()
+
+    debug.debug = args.debug
+
+    if len(args.refs) < 2:
+        debug.eprint('Two refs needed to get a ChangeLog.')
+        sys.exit(os.EX_USAGE)
+
+    REPO = {'git': GitRepo(project_quirks.IGNORE_LIST, debug)}
+
+    fe_c = frontend_c.Frontend(project_quirks, debug)
+    FRONTENDS = {'.c': fe_c,
+                 '.h': fe_c}
+
+    main(REPO[project_quirks.repo], FRONTENDS, args.refs)