As per the centithread on ksummit-discuss [1], there are folks who feel that if a Change-Id is present in a developer's local commit that said Change-Id could be interesting to include in upstream posts. Specifically if two commits are posted with the same Change-Id there's a reasonable chance that they are either the same commit or a newer version of the same commit. Specifically this is because that's how gerrit has trained people to work.

There is much angst about Change-Id in upstream Linux, but one thing that seems safe and non-controversial is to include the Change-Id as part of the string of crud that makes up a Message-Id.

Let's give that a try.

In theory (if there is enough adoption) this could help a tool more reliably find various versions of a commit. This actually might work pretty well for U-Boot where (I believe) quite a number of developers use patman, so there could be critical mass (assuming that enough of these people also use a git hook that adds Change-Id to their commits). I was able to find this git hook by searching for "gerrit change id git hook" in my favorite search engine.

In theory one could imagine something like this could be integrated into other tools, possibly even git-send-email. Getting it into patman seems like a sane first step, though.

NOTE: this patch is being posted using a patman containing this patch, so you should be able to see the Message-Id of this patch and see that it contains my local Change-Id, which ends in 2b9 if you want to check.

[1] https://lists.linuxfoundation.org/pipermail/ksummit-discuss/2019-August/0067...

Signed-off-by: Douglas Anderson dianders@chromium.org ---

Changes in v3: - Allow faking the time of Message-Id for testing (testBasic) - Add skip_blank for Change-Id (testBasic). - Check the Message-Id in testBasic.

Changes in v2: - Add a "v" before the version part of the Message-Id - Reorder the parts of the Message-Id as per Johannes.

tools/patman/README | 8 ++++- tools/patman/commit.py | 3 ++ tools/patman/patchstream.py | 64 +++++++++++++++++++++++++++++++++++-- tools/patman/test.py | 15 +++++++-- 4 files changed, 85 insertions(+), 5 deletions(-)

diff --git a/tools/patman/README b/tools/patman/README index 7917fc8bdc33..02d582974495 100644 --- a/tools/patman/README +++ b/tools/patman/README @@ -259,12 +259,18 @@ Series-process-log: sort, uniq unique entries. If omitted, no change log processing is done. Separate each tag with a comma.

+Change-Id: + This tag is stripped out but is used to generate the Message-Id + of the emails that will be sent. When you keep the Change-Id the + same you are asserting that this is a slightly different version + (but logically the same patch) as other patches that have been + sent out with the same Change-Id. + Various other tags are silently removed, like these Chrome OS and Gerrit tags:

BUG=... TEST=... -Change-Id: Review URL: Reviewed-on: Commit-xxxx: (except Commit-notes) diff --git a/tools/patman/commit.py b/tools/patman/commit.py index 2bf3a0ba5b92..48d0529c5365 100644 --- a/tools/patman/commit.py +++ b/tools/patman/commit.py @@ -21,6 +21,8 @@ class Commit: The dict is indexed by change version (an integer) cc_list: List of people to aliases/emails to cc on this commit notes: List of lines in the commit (not series) notes + change_id: the Change-Id: tag that was stripped from this commit + and can be used to generate the Message-Id. """ def __init__(self, hash): self.hash = hash @@ -30,6 +32,7 @@ class Commit: self.cc_list = [] self.signoff_set = set() self.notes = [] + self.change_id = None

def AddChange(self, version, info): """Add a new change line to the change list for a version. diff --git a/tools/patman/patchstream.py b/tools/patman/patchstream.py index b6455b0fa383..ef0660629795 100644 --- a/tools/patman/patchstream.py +++ b/tools/patman/patchstream.py @@ -2,6 +2,7 @@ # Copyright (c) 2011 The Chromium OS Authors. #

+import datetime import math import os import re @@ -14,7 +15,7 @@ import gitutil from series import Series

# Tags that we detect and remove -re_remove = re.compile('^BUG=|^TEST=|^BRANCH=|^Change-Id:|^Review URL:' +re_remove = re.compile('^BUG=|^TEST=|^BRANCH=|^Review URL:' '|Reviewed-on:|Commit-\w*:')

# Lines which are allowed after a TEST= line @@ -32,6 +33,9 @@ re_cover_cc = re.compile('^Cover-letter-cc: *(.*)') # Patch series tag re_series_tag = re.compile('^Series-([a-z-]*): *(.*)')

+# Change-Id will be used to generate the Message-Id and then be stripped +re_change_id = re.compile('^Change-Id: *(.*)') + # Commit series tag re_commit_tag = re.compile('^Commit-([a-z-]*): *(.*)')

@@ -156,6 +160,7 @@ class PatchStream:

# Handle state transition and skipping blank lines series_tag_match = re_series_tag.match(line) + change_id_match = re_change_id.match(line) commit_tag_match = re_commit_tag.match(line) cover_match = re_cover.match(line) cover_cc_match = re_cover_cc.match(line) @@ -177,7 +182,7 @@ class PatchStream: self.state = STATE_MSG_HEADER

# If a tag is detected, or a new commit starts - if series_tag_match or commit_tag_match or \ + if series_tag_match or commit_tag_match or change_id_match or \ cover_match or cover_cc_match or signoff_match or \ self.state == STATE_MSG_HEADER: # but we are already in a section, this means 'END' is missing @@ -275,6 +280,16 @@ class PatchStream: self.AddToSeries(line, name, value) self.skip_blank = True

+ # Detect Change-Id tags + elif change_id_match: + value = change_id_match.group(1) + if self.is_log: + if self.commit.change_id: + raise ValueError("%s: Two Change-Ids: '%s' vs. '%s'" % + (self.commit.hash, self.commit.change_id, value)) + self.commit.change_id = value + self.skip_blank = True + # Detect Commit-xxx tags elif commit_tag_match: name = commit_tag_match.group(1) @@ -345,6 +360,47 @@ class PatchStream: self.warn.append('Found %d lines after TEST=' % self.lines_after_test)

+ def WriteMessageId(self, outfd): + """Write the Message-Id into the output. + + This is based on the Change-Id in the original patch, the version, + and the prefix. + + Args: + outfd: Output stream file object + """ + if not self.commit.change_id: + return + + # If the count is -1 we're testing, so use a fixed time + if self.commit.count == -1: + time_now = datetime.datetime(1999, 12, 31, 23, 59, 59) + else: + time_now = datetime.datetime.now() + + # In theory there is email.utils.make_msgid() which would be nice + # to use, but it already produces something way too long and thus + # will produce ugly commit lines if someone throws this into + # a "Link:" tag in the final commit. So (sigh) roll our own. + + # Start with the time; presumably we wouldn't send the same series + # with the same Change-Id at the exact same second. + parts = [time_now.strftime("%Y%m%d%H%M%S")] + + # These seem like they would be nice to include. + if 'prefix' in self.series: + parts.append(self.series['prefix']) + if 'version' in self.series: + parts.append("v%s" % self.series['version']) + + parts.append(str(self.commit.count + 1)) + + # The Change-Id must be last, right before the @ + parts.append(self.commit.change_id) + + # Join parts together with "." and write it out. + outfd.write('Message-Id: %s@changeid\n' % '.'.join(parts)) + def ProcessStream(self, infd, outfd): """Copy a stream from infd to outfd, filtering out unwanting things.

@@ -358,6 +414,9 @@ class PatchStream: fname = None last_fname = None re_fname = re.compile('diff --git a/(.*) b/.*') + + self.WriteMessageId(outfd) + while True: line = infd.readline() if not line: @@ -481,6 +540,7 @@ def FixPatches(series, fnames): for fname in fnames: commit = series.commits[count] commit.patch = fname + commit.count = count result = FixPatch(backup_dir, fname, series, commit) if result: print('%d warnings for %s:' % (len(result), fname)) diff --git a/tools/patman/test.py b/tools/patman/test.py index e1b94bd1a7db..cc61c20606e8 100644 --- a/tools/patman/test.py +++ b/tools/patman/test.py @@ -12,6 +12,7 @@ import checkpatch import gitutil import patchstream import series +import commit

class TestPatch(unittest.TestCase): @@ -48,7 +49,8 @@ Signed-off-by: Simon Glass sjg@chromium.org arch/arm/cpu/armv7/tegra2/ap20.c | 57 ++---- arch/arm/cpu/armv7/tegra2/clock.c | 163 +++++++++++++++++ ''' - expected=''' + expected='''Message-Id: 19991231235959.0.I80fe1d0c0b7dd10aa58ce5bb1d9290b6664d5413@changeid +

From 656c9a8c31fa65859d924cd21da920d6ba537fad Mon Sep 17 00:00:00 2001 From: Simon Glass sjg@chromium.org @@ -79,7 +81,16 @@ Signed-off-by: Simon Glass sjg@chromium.org expfd.write(expected) expfd.close()

- patchstream.FixPatch(None, inname, series.Series(), None) + # Normally by the time we call FixPatch we've already collected + # metadata. Here, we haven't, but at least fake up something. + # Set the "count" to -1 which tells FixPatch to use a bogus/fixed + # time for generating the Message-Id. + com = commit.Commit('') + com.change_id = 'I80fe1d0c0b7dd10aa58ce5bb1d9290b6664d5413' + com.count = -1 + + patchstream.FixPatch(None, inname, series.Series(), com) + rc = os.system('diff -u %s %s' % (inname, expname)) self.assertEqual(rc, 0)