Merge branch 'bk/sob-dco' into jch

Document that the meaning of a Signed-off-by trailer can vary from
project to project in the end-user documentation, and clarify what
it means to this project.

* bk/sob-dco:
  SubmittingPatches: clarify DCO is our --signoff rule
  Documentation: clarify and expand description of --signoff
  doc: preparatory clean-up of description on the sign-off option

Documentation/SubmittingPatches

@@ -300,15 +300,12 @@ patch.
 [[sign-off]]
 === Certify your work by adding your "Signed-off-by: " line
 
-To improve tracking of who did what, we've borrowed the
-"sign-off" procedure from the Linux kernel project on patches
-that are being emailed around.  Although core Git is a lot
-smaller project it is a good discipline to follow it.
+To improve tracking of who did what, we ask you to certify that you
+wrote the patch or have the right to pass it on under the same license
+as ours, by "signing off" your patch.  Without sign-off, we cannot
+accept your patches.
 
-The sign-off is a simple line at the end of the explanation for
-the patch, which certifies that you wrote it or otherwise have
-the right to pass it on as an open-source patch.  The rules are
-pretty simple: if you can certify the below D-C-O:
+If you can certify the below D-C-O:
 
 [[dco]]
 .Developer's Certificate of Origin 1.1
@@ -338,14 +335,15 @@ d. I understand and agree that this project and the contribution
    this project or the open source license(s) involved.
 ____
 
-then you just add a line saying
+you add a "Signed-off-by" trailer to your commit, that looks like
+this:
 
 ....
 	Signed-off-by: Random J Developer <random@developer.example.org>
 ....
 
-This line can be automatically added by Git if you run the git-commit
-command with the -s option.
+This line can be added by Git if you run the git-commit command with
+the -s option.
 
 Notice that you can place your own Signed-off-by: line when
 forwarding somebody else's patch with the above rules for
@@ -353,6 +351,11 @@ D-C-O.  Indeed you are encouraged to do so.  Do not forget to
 place an in-body "From: " line at the beginning to properly attribute
 the change to its true author (see (2) above).
 
+This procedure originally came from the Linux kernel project, so our
+rule is quite similar to theirs, but what exactly it means to sign-off
+your patch differs from project to project, so it may be different
+from that of the project you are accustomed to.
+
 [[real-name]]
 Also notice that a real name is used in the Signed-off-by: line. Please
 don't hide your real name.

Documentation/git-commit.txt

@@ -59,6 +59,7 @@ commit by giving the same set of parameters (options and paths).
 If you make a commit and then find a mistake immediately after
 that, you can recover from it with 'git reset'.
 
+:git-commit: 1
 
 OPTIONS
 -------
@@ -163,14 +164,7 @@ The `-m` option is mutually exclusive with `-c`, `-C`, and `-F`.
 	message, the commit is aborted.  This has no effect when a message
 	is given by other means, e.g. with the `-m` or `-F` options.
 
--s::
---signoff::
-	Add Signed-off-by line by the committer at the end of the commit
-	log message.  The meaning of a signoff depends on the project,
-	but it typically certifies that committer has
-	the rights to submit this work under the same license and
-	agrees to a Developer Certificate of Origin
-	(see http://developercertificate.org/ for more information).
+include::signoff-option.txt[]
 
 -n::
 --no-verify::

Documentation/merge-options.txt

@@ -77,16 +77,7 @@ When not possible, refuse to merge and exit with a non-zero status.
 With --no-log do not list one-line descriptions from the
 actual commits being merged.
 
---signoff::
---no-signoff::
-	Add Signed-off-by line by the committer at the end of the commit
-	log message.  The meaning of a signoff depends on the project,
-	but it typically certifies that committer has
-	the rights to submit this work under the same license and
-	agrees to a Developer Certificate of Origin
-	(see http://developercertificate.org/ for more information).
-+
-With --no-signoff do not add a Signed-off-by line.
+include::signoff-option.txt[]
 
 --stat::
 -n::

Documentation/signoff-option.txt

+ifdef::git-commit[]
+-s::
+endif::git-commit[]
+--signoff::
+--no-signoff::
+	Add a Signed-off-by trailer by the committer at the end of the commit
+	log message.  The meaning of a signoff depends on the project
+	to which you're committing.  For example, it may certify that
+	the committer has the rights to submit the work under the
+	project's license or agrees to some contributor representation,
+	such as a Developer Certificate of Origin.
+	(See http://developercertificate.org for the one used by the
+	Linux kernel and Git projects.)  Consult the documentation or
+	leadership of the project to which you're contributing to
+	understand how the signoffs are used in that project.
++
+The --no-signoff option can be used to countermand an earlier --signoff
+option on the command line.