first version of license header reporter

license-headers.py

@@ -0,0 +1,88 @@
+#!/usr/bin/env python
+#
+# Copyright (c) 2011 Free Software Foundation, Inc.
+# Written by Brett Smith <brett@fsf.org>
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+# 
+#   http://www.apache.org/licenses/LICENSE-2.0
+# 
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# This program recursively greps the current directory for things that
+# look like license statements, and then prints out a report about
+# which files have which statements.  This is useful for picking
+# through a project that has standard license boilerplate on most
+# files, but a few exceptions; it's easy to pick out the oddballs with
+# the report.
+
+# Ideas for improvement:
+# * Better output formatting.  Sort by frequency.
+# * Modify the grep options with command line arguments.
+# * Smarter logic about what makes a license statement.  Something to make
+#   this less sensitive to line wrapping issues and things like that.
+
+import subprocess
+
+class LicenseFilenameMismatch(Exception):
+    pass
+
+
+class LicenseData(object):
+    def add_line(self, line):
+        current_filename = getattr(self, 'filename', None)
+        filename, text = line.split('\0')
+        if current_filename is None:
+            self.filename = filename
+            self.text = [text]
+        elif current_filename == filename:
+            self.text.append(text)
+        else:
+            raise LicenseFilenameMismatch
+        
+
+class LicenseFiler(object):
+    def __init__(self):
+        self.licenses = {}
+        self.process = subprocess.Popen(['grep', '-Zir', 'license', '.'],
+                                        stdout=subprocess.PIPE)
+        self.parse_grep()
+
+    def save_license(self, license):
+        if not getattr(license, 'text', None):
+            return
+        filenames = self.licenses.setdefault(tuple(license.text), set())
+        filenames.add(license.filename)
+
+    def parse_grep(self):
+        current_license = LicenseData()
+        for line in self.process.stdout:
+            try:
+                current_license.add_line(line)
+            except LicenseFilenameMismatch:
+                self.save_license(current_license)
+                current_license = LicenseData()
+                current_license.add_line(line)
+        self.save_license(current_license)
+        self.process.stdout.close()
+        self.process.wait()
+        
+    def report(self):
+        for text, filenames in self.licenses.items():
+            print "".join(text)
+            print "\n".join(("\t" + fn for fn in filenames))
+            print
+
+
+def main(args):
+    filer = LicenseFiler()
+    filer.report()
+
+if __name__ == '__main__':
+    main([])