Add 'patman' patch generation, checking and submission script

What is this?

=============

This tool is a Python script which:
- Creates patch directly from your branch
- Cleans them up by removing unwanted tags
- Inserts a cover letter with change lists
- Runs the patches through checkpatch.pl and its own checks
- Optionally emails them out to selected people

It is intended to automate patch creation and make it a less
error-prone process. It is useful for U-Boot and Linux work so far,
since it uses the checkpatch.pl script.

It is configured almost entirely by tags it finds in your commits.
This means that you can work on a number of different branches at
once, and keep the settings with each branch rather than having to
git format-patch, git send-email, etc. with the correct parameters
each time. So for example if you put:

in one of your commits, the series will be sent there.

See the README file for full details.
END

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/patman/commit.py b/tools/patman/commit.py
new file mode 100644
index 0000000..7144e54
--- /dev/null
+++ b/tools/patman/commit.py
@@ -0,0 +1,87 @@
+# Copyright (c) 2011 The Chromium OS Authors.
+#
+# See file CREDITS for list of people who contributed to this
+# project.
+#
+# 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 2 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, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+# MA 02111-1307 USA
+#
+
+import re
+
+# Separates a tag: at the beginning of the subject from the rest of it
+re_subject_tag = re.compile('([^:]*):\s*(.*)')
+
+class Commit:
+    """Holds information about a single commit/patch in the series.
+
+    Args:
+        hash: Commit hash (as a string)
+
+    Variables:
+        hash: Commit hash
+        subject: Subject line
+        tags: List of maintainer tag strings
+        changes: Dict containing a list of changes (single line strings).
+            The dict is indexed by change version (an integer)
+        cc_list: List of people to aliases/emails to cc on this commit
+    """
+    def __init__(self, hash):
+        self.hash = hash
+        self.subject = None
+        self.tags = []
+        self.changes = {}
+        self.cc_list = []
+
+    def AddChange(self, version, info):
+        """Add a new change line to the change list for a version.
+
+        Args:
+            version: Patch set version (integer: 1, 2, 3)
+            info: Description of change in this version
+        """
+        if not self.changes.get(version):
+            self.changes[version] = []
+        self.changes[version].append(info)
+
+    def CheckTags(self):
+        """Create a list of subject tags in the commit
+
+        Subject tags look like this:
+
+            propounder: Change the widget to propound correctly
+
+        Multiple tags are supported. The list is updated in self.tag
+
+        Returns:
+            None if ok, else the name of a tag with no email alias
+        """
+        str = self.subject
+        m = True
+        while m:
+            m = re_subject_tag.match(str)
+            if m:
+                tag = m.group(1)
+                self.tags.append(tag)
+                str = m.group(2)
+        return None
+
+    def AddCc(self, cc_list):
+        """Add a list of people to Cc when we send this patch.
+
+        Args:
+            cc_list:    List of aliases or email addresses
+        """
+        self.cc_list += cc_list