all: update for Git

- rewrite .gitignore to use git patterns
- mv hg(1) to git(1) and rewrite
- add lib/git/commit-msg.hook
- add skeleton codereview script
- update codereview(1)

Change-Id: I061cd8e4de77ebbd6037a7c5d1582cd1d986f62f

.gitignore

@@ -1,27 +1,23 @@
-(^|/)CVS($|/)
+plan9.log
-(^|/)\.hg($|/)
+plan9-reverse.log
-(^|/)\.hgtags($|/)
+state
-^plan9.log$
+state.old
-^plan9-reverse.log$
+state.journal
-^state$
+*.o
-^state.old$
+*.a
-^state.journal$
+man/man?/*.html
-\.o$
+src/**/o.*
-\.a$
+y.tab.[ch]
-^man/man[0-9]+/.*\.html$
+src/cmd/rc/x.tab.h
-^src/.*/o\.[^/]+$
+unix/*.tgz
-y.tab.[ch]$
+bin/
-^src/cmd/rc/x.tab.h$
+log/
-^unix/.*\.tgz$
+dict/
-^bin/
+postscript/font/
-^log/
+*.orig
-^dict/
-^postscript/font/
-\.orig$
 config
 install.log
 install.sum
 last-change
-lib/codereview/codereview.pyc
 src/cmd/awk/y.output
 src/cmd/devdraw/latin1.h

bin/codereview

@@ -1,2 +1,142 @@
-#!/bin/sh
+#!/usr/local/plan9/bin/rc
-$PLAN9/bin/codereview.py -r rsc --cc codebot --send_mail "$@"
+
+git=git
+show=false
+fn gitshow {
+	echo '%' git $*
+	git $*
+}
+if(! ~ $#* 0 && ~ $1 -v) {
+	git=gitshow
+	show=true
+	shift
+}
+	
+if(~ $#* 0) {
+	echo 'usage: codereview <command> <args>' >[1=2]
+	exit usage
+}
+
+if(~ $#PLAN9 0) {
+	PLAN9=/usr/local/plan9
+}
+if(! test -d $PLAN9/lib/git) {
+	echo 'codereview: cannot find $PLAN9/lib/git' >[1=2]
+	exit git
+}
+
+if(! test -e $PLAN9/.git/hooks/commit-msg) {
+	if($show) {
+		echo '% ln -s ../../lib/git/commit-msg.hook $PLAN9/.git/hooks/commit-msg'
+	}
+	ln -s ../../lib/git/commit-msg.hook $PLAN9/.git/hooks/commit-msg
+}
+
+switch($1) {
+case help
+	9 man 1 codereview
+
+case pending
+	shift
+	if(! ~ $#* 0) {
+		echo 'usage: codereview pending' >[1=2]
+		exit usage
+	}
+	$git branch --list
+
+case create
+	shift
+	if(! ~ $#* 1) {
+		echo 'usage: codereview create branchname' >[1=2]
+		exit usage
+	}
+	branch=$1
+	if(! git branch -l | 9 grep '\* master$') {
+		echo 'codereview: create not on master branch; use codereview commit' >[1=2]
+		exit master
+	}
+	if($show) {
+		echo '% git branch '$branch' && git commit || git branch -d '$branch >[1=2]
+	}
+	git branch $branch && git commit $* || git branch -d $branch
+
+case commit
+	shift
+	if(git branch -l | 9 grep '\* master$') {
+		echo 'codereview: commit on master branch; use codereview create <branchname>' >[1=2]
+		exit master
+	}
+	if(~ `{git merge-base HEAD HEAD} `{git merge-base HEAD master}) {
+		# first commit on branch, somehow.
+		$git commit $*
+		exit $status
+	}
+	$git commit --amend $*
+	exit $status
+
+case upload
+	if(git branch -l | 9 grep '\* master$') {
+		echo 'codereview: upload on master branch' >[1=2]
+		exit master
+	}
+	if(~ `{git merge-base HEAD HEAD} `{git merge-base HEAD master}) {
+		# no commit on branch
+		echo 'codereview: no commits yet on this feature branch' >[1=2]
+		exit commit
+	}
+	if(! 9 grep 'machine plan9port-review.googlesource.com' $HOME/.netrc >/dev/null >[2=1]) {
+		echo 'codereview: warning: cannot find plan9port-review in netrc' >[1=2]
+	}
+	$git push https://plan9port-review.googlesource.com/plan9 HEAD:refs/for/master >[2=1] | 9 sed 's/.*
//'
+
+case sync
+	shift
+	if(! ~ $#* 0) {
+		echo 'usage: codereview sync' >[1=2]
+		exit usage
+	}
+	$git fetch -q
+	
+	branch=`{git branch -l | 9 sed -n 's/^\* //p'}
+	if(~ $branch master) {
+		$git merge -q --ff-only origin/master
+		exit $status
+	}
+
+	if(~ `{git merge-base HEAD HEAD} `{git merge-base HEAD master}) {
+		# no commit on branch
+		git merge -q --ff-only origin/master
+		exit $status
+	}
+
+	# Exactly this commit in master. Fast-forward from master and delete this branch.
+	if(git branch -r --contains HEAD | 9 grep '^ *origin/master$') {
+		$git checkout -q master
+		$git merge -q --ff-only origin/master
+		$git branch -q -d $branch
+		exit $status
+	}
+	
+	changeid=`{git log -n 1 | 9 sed -n 's/^    Change-Id: //p'}
+	if(~ $#changeid 0) {
+		echo 'codereview: cannot find change id'
+		exit changeid
+	}
+
+	if(git log --grep 'Change-Id: '$changeid origin/master | 9 grep .) {
+		# Something like this got submitted.
+		$git checkout -q master
+		$git merge -q --ff-only origin/master
+		echo 'Change submitted but perhaps not identical to your copy.' >[1=2]
+		echo 'To remove old copy:' git branch -d $branch >[1=2]
+		exit 1
+	}
+	
+	if(git branch -r --contains master | 9 grep '^ *origin/master$')
+		$git branch -f master origin/master
+	$git rebase -q origin/master
+
+case *
+	echo 'codereview: unrecognized command '$1 >[1=2]
+	exit usage
+}

lib/git/commit-msg.hook

@@ -0,0 +1,104 @@
+#!/bin/sh
+# From Gerrit Code Review 2.2.1
+#
+# Part of Gerrit Code Review (http://code.google.com/p/gerrit/)
+#
+# Copyright (C) 2009 The Android Open Source Project
+#
+# 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.
+#
+
+CHANGE_ID_AFTER="Bug|Issue"
+MSG="$1"
+
+# Check for, and add if missing, a unique Change-Id
+#
+add_ChangeId() {
+	clean_message=`sed -e '
+		/^diff --git a\/.*/{
+			s///
+			q
+		}
+		/^Signed-off-by:/d
+		/^#/d
+	' "$MSG" | git stripspace`
+	if test -z "$clean_message"
+	then
+		return
+	fi
+
+	if grep -i '^Change-Id:' "$MSG" >/dev/null
+	then
+		return
+	fi
+
+	id=`_gen_ChangeId`
+	perl -e '
+		$MSG = shift;
+		$id = shift;
+		$CHANGE_ID_AFTER = shift;
+
+		undef $/;
+		open(I, $MSG); $_ = <I>; close I;
+		s|^diff --git a/.*||ms;
+		s|^#.*$||mg;
+		exit unless $_;
+
+		@message = split /\n/;
+		$haveFooter = 0;
+		$startFooter = @message;
+		for($line = @message - 1; $line >= 0; $line--) {
+			$_ = $message[$line];
+
+			if (/^[a-zA-Z0-9-]+:/ && !m,^[a-z0-9-]+://,) {
+				$haveFooter++;
+				next;
+			}
+			next if /^[ []/;
+			$startFooter = $line if ($haveFooter && /^\r?$/);
+			last;
+		}
+
+		@footer = @message[$startFooter+1..@message];
+		@message = @message[0..$startFooter];
+		push(@footer, "") unless @footer;
+
+		for ($line = 0; $line < @footer; $line++) {
+			$_ = $footer[$line];
+			next if /^($CHANGE_ID_AFTER):/i;
+			last;
+		}
+		splice(@footer, $line, 0, "Change-Id: I$id");
+
+		$_ = join("\n", @message, @footer);
+		open(O, ">$MSG"); print O; close O;
+	' "$MSG" "$id" "$CHANGE_ID_AFTER"
+}
+_gen_ChangeIdInput() {
+	echo "tree `git write-tree`"
+	if parent=`git rev-parse HEAD^0 2>/dev/null`
+	then
+		echo "parent $parent"
+	fi
+	echo "author `git var GIT_AUTHOR_IDENT`"
+	echo "committer `git var GIT_COMMITTER_IDENT`"
+	echo
+	printf '%s' "$clean_message"
+}
+_gen_ChangeId() {
+	_gen_ChangeIdInput |
+	git hash-object -t commit --stdin
+}
+
+
+add_ChangeId

man/man1/codereview.1

@@ -2,70 +2,154 @@
 .SH NAME
 codereview \- review of submitted changes (experimental)
 .SH SYNOPSIS
-.B hg
+.B git
 .B diff
+.B HEAD
 .I path ...
 .PP
 .B codereview
-.I path ...
+[
+.B -v
+]
+.B create
+.I name
+[
+.B -a
+]
 .PP
 .B codereview
-.B -i
+[
-.I issue
+.B -v
-.I path ...
+]
+.B commit
+[
+.B -a
+]
+.PP
+.B codereview
+[
+.B -v
+]
+.B upload
+.PP
+.B codereview
+[
+.B -v
+]
+.B pending
+.PP
+.B codereview
+[
+.B -v
+]
+.B sync
 .SH DESCRIPTION
 .I Codereview
-uploads suggested changes to the code review server
+manages the review and submission of changes to the Plan 9 from User Space project.
-.I codereview.appspot.com
-and sends email to reviewers.
 It must be used from within a Plan 9 from User Space tree
-checked out via Mercurial
+checked out via Git
 (see
-.IR hg (1)).
+.IR git (1)).
 .PP
-A developer makes changes to a local copy of the tree
+A developer makes changes to a local copy of the tree,
-and reviews them locally using 
+reviews them by using
-.I hg
+.I git
-.I diff .
+.I diff
-When the changes are ready for external review, the 
+.IR HEAD 
-developer creates a review issue by running
+and then commits them to a ``feature branch''
+using
 .I codereview
-naming the files to be reviewed.
+.IR create .
-.I Codereview
+.I Git
-prompts for a Google Accounts user name
+requires that changes be added to a ``staging area'' before the initial commit,
-and password to log in to 
+using commands such as
-.I http://codereview.appspot.com/
+.I git
-and create a new review issue.
+.I add
-Once created, it prints a line like
+and
-.EX
+.I git
-Issue created. URL: http://codereview.appspot.com/96161
+.IR rm .
-.EE
+The 
-among other output.
+.B -a
-.PP
+option causes
-The reviewer will likely respond with comments
-and suggestions for improving the submission.
-After making the changes, reupload by repeating
-the 
 .I codereview
-command with the
+.I create
-.B -i
+to add all local modifications to the staging area as part of the initial commit.
-option to specify the issue number
+.PP
-(in the above example, 96161).
+Once a feature branch is created, files can still be edited, but they must then be
+incorporated into the change by using
+.I codereview
+.IR commit .
+.PP
+If other changes have been committed since the feature branch was created,
+.I codereview
+.I sync
+will update it to be based on the most recent copy of the repository.
+.PP
+When the code is ready for review,
+.I codereview
+.I upload
+uploads the change to 
+.HR https://plan9port-review.googlesource.com/
+for review.
+In order to upload, 
+.I git
+must have access to a 
+.I $HOME/.netrc
+that contains a password obtained from
+.HR https://plan9port-review.googlesource.com/#/settings/http-password .
+.PP
+The most likely initial result of a code review is suggestions for
+improving the code.
+After making those changes, repeat the
+.I codereview
+.I commit
+and 
+.I codereview
+.I upload
+steps.
+.PP
+Once the code is ready, it will be submitted by the reviewer using the web interface.
+At that point,
+.I codereview
+.I sync
 .PP
-Once the reviewer accepts the changes, they will be applied
-automatically using the patch uploaded to the review server.
-To update the local tree, run 
-.I hg
-.I pull
-with the
-.B -u
-option.
-.SH SEE ALSO
-.HR http://codereview.appspot.com/
-.SH BUGS
 The
 .I codereview
-command should be replaced by a proper Mercurial extension.
+.I pending
+command lists the active feature branches.
 .PP
-Making changes to the repository via patches
+All the
-discards the executable bit on new shell scripts.
+.I codereview
+commands take a leading
+.B -v
+option, which causes them to print
+.I git
+commands being executed.
+This can be useful for debugging
+.IR codereview .
+.PP
+The
+.I codereview
+command depends on a 
+.I git
+``commit hook''
+script being in place to add
+.L Change-Id
+lines to the commit messages.
+.I Codereview
+installs the hook at startup, if necessary,
+by adding a symbolic link from
+.B $PLAN9/.git/hooks/commit-msg
+to
+.BR $PLAN9/lib/git/commit-msg.hook .
+.SH SEE ALSO
+.IR git (1),
+.HR http://plan9port-review.googlesource.com/
+.SH BUGS
+.I Git
+is too complicated to use.
+The 
+.I codereview
+script helps, but a working understanding of
+.I git
+is still required.

man/man1/git.1

@@ -1,42 +1,34 @@
 .TH HG 1
 .SH NAME 
-hg, cvs \- introduction to using plan9port Mercurial repository
+git, hg, cvs \- introduction to using plan9port Git repository
 .SH SYNOPSIS
-.B hg
+.B git
 .B clone
 .B http://code.swtch.com/plan9port
 .B plan9
 .PP
-.B hg
+.B git
 .B pull
-.B -u
 .PP
-.B hg
+.B git
 .B diff
-[
-.B -r
 .I revision
-]
 [
 .I path ...
 ]
 .PP
-.B hg 
+.B gitk 
-.B serve
-.PP
-.B hg 
-.B view
 .PP
 .B web
 .B http://code.swtch.com/plan9port
 .SH DESCRIPTION
 The master source tree for Plan 9 from User Space is maintained
-using the source control system Mercurial
+using the source control system Git
 as a substitute for Plan 9's
 \fIreplica\fR(8) and dump file system.
 .PP
 The first argument to
-.I hg
+.I git
 is a command, which determines the form of the rest of the command line.
 .PP
 The
@@ -45,67 +37,53 @@ command downloads a copy of the tree into the directory
 .BR plan9 ,
 which it will create.
 After
-.B hg
+.B git
 .BR clone ,
 the other commands listed 
 should be run within the
 .B plan9
 directory tree.
 .PP
-Unlike CVS, Mercurial downloads the entire revision history
+Git downloads the entire revision history
 of Plan 9 from User Space 
 in addition to the current tree.
 .PP
-.I Hg
+.I Git
 .I pull
 incorporates changes from the master repository
-into the local revision history.
+into the local revision history and applies them to the
-The 
+current file tree.
-.B -u
-flag applies these changes to the current file tree.
 .PP
-.I Hg
+.I Git
 .I diff
 runs Unix's
 .IR diff (1)
 to compare the files in the local tree with the corresponding
 files in the revision history.
-By default it compares against the version that was most recently
-incorporated into the local tree.
-The
-.B -r
-flag specifies an alternate version to compare against.
 The special revision
-.B tip
+.B HEAD
-refers to the most recent version on the server.
+refers to the most recent version in the version history.
 .PP
-.I Hg
+.I Gitk
-.I serve
-starts an HTTP server serving information about
-the local repository at the address
-.BR http://localhost:8000/ .
-.PP
-.I Hg
-.I view
 starts an interactive history viewer.
 .PP
-The Mercurial tree can be inspected on the web at
+The Git tree can be inspected on the web at
 .HR http://code.swtch.com/plan9port/ "" .
 .SH FILES
 .TP
-.B \*9/.hg
+.B \*9/.git
 directory containing Mercurial local repository
 .TP
-.B .hgignore
+.B .gitignore
-list of files and wildcards to exclude from Mercurial operations
+list of files and wildcards to exclude from Git operations
 .SH SEE ALSO
 .IR codereview (1)
 .PP
 Unix's
-\fIhg\fR(1),
+\fIgit\fR(1),
-.HR http://www.selenic.com/mercurial/wiki/
+.HR http://git-scm.com/doc
 .PP
 .HR http://code.swtch.com/plan9port/
 .SH BUGS
-Plan 9 from User Space is no longer accessible using CVS;
+Plan 9 from User Space is no longer accessible using CVS or Mercurial;
-you must use Mercurial.
+you must use Git.