Merge branch 'sb/push-options'

"git push" learned to accept and pass extra options to the
receiving end so that hooks can read and react to them.

* sb/push-options:
  add a test for push options
  push: accept push options
  receive-pack: implement advertising and receiving push options
  push options: {pre,post}-receive hook learns about push options

5 files changed, 47 insertions, 7 deletions

diff --git a/Documentation/config.txt b/Documentation/config.txt
index 8b1aee4b3b..4ae564b487 100644
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -2427,8 +2427,13 @@ rebase.instructionFormat
 
 receive.advertiseAtomic::
 	By default, git-receive-pack will advertise the atomic push
-	capability to its clients. If you don't want to this capability
-	to be advertised, set this variable to false.
+	capability to its clients. If you don't want to advertise this
+	capability, set this variable to false.
+
+receive.advertisePushOptions::
+	By default, git-receive-pack will advertise the push options
+	capability to its clients. If you don't want to advertise this
+	capability, set this variable to false.
 
 receive.autogc::
 	By default, git-receive-pack will run "git-gc --auto" after
diff --git a/Documentation/git-push.txt b/Documentation/git-push.txt
index 93c3527f0c..ec514f6cd5 100644
--- a/Documentation/git-push.txt
+++ b/Documentation/git-push.txt
@@ -11,7 +11,7 @@ SYNOPSIS
 [verse]
 'git push' [--all | --mirror | --tags] [--follow-tags] [--atomic] [-n | --dry-run] [--receive-pack=<git-receive-pack>]
 	   [--repo=<repository>] [-f | --force] [-d | --delete] [--prune] [-v | --verbose]
-	   [-u | --set-upstream]
+	   [-u | --set-upstream] [--push-option=<string>]
 	   [--[no-]signed|--sign=(true|false|if-asked)]
 	   [--force-with-lease[=<refname>[:<expect>]]]
 	   [--no-verify] [<repository> [<refspec>...]]
@@ -156,6 +156,12 @@ already exists on the remote side.
 	Either all refs are updated, or on error, no refs are updated.
 	If the server does not support atomic pushes the push will fail.
 
+-o::
+--push-option::
+	Transmit the given string to the server, which passes them to
+	the pre-receive as well as the post-receive hook. The given string
+	must not contain a NUL or LF character.
+
 --receive-pack=<git-receive-pack>::
 --exec=<git-receive-pack>::
 	Path to the 'git-receive-pack' program on the remote
diff --git a/Documentation/githooks.txt b/Documentation/githooks.txt
index d82e912e55..9565dc3fda 100644
--- a/Documentation/githooks.txt
+++ b/Documentation/githooks.txt
@@ -247,6 +247,15 @@ Both standard output and standard error output are forwarded to
 'git send-pack' on the other end, so you can simply `echo` messages
 for the user.
 
+The number of push options given on the command line of
+`git push --push-option=...` can be read from the environment
+variable `GIT_PUSH_OPTION_COUNT`, and the options themselves are
+found in `GIT_PUSH_OPTION_0`, `GIT_PUSH_OPTION_1`,...
+If it is negotiated to not use the push options phase, the
+environment variables will not be set. If the client selects
+to use push options, but doesn't transmit any, the count variable
+will be set to zero, `GIT_PUSH_OPTION_COUNT=0`.
+
 [[update]]
 update
 ~~~~~~
@@ -322,6 +331,15 @@ a sample script `post-receive-email` provided in the `contrib/hooks`
 directory in Git distribution, which implements sending commit
 emails.
 
+The number of push options given on the command line of
+`git push --push-option=...` can be read from the environment
+variable `GIT_PUSH_OPTION_COUNT`, and the options themselves are
+found in `GIT_PUSH_OPTION_0`, `GIT_PUSH_OPTION_1`,...
+If it is negotiated to not use the push options phase, the
+environment variables will not be set. If the client selects
+to use push options, but doesn't transmit any, the count variable
+will be set to zero, `GIT_PUSH_OPTION_COUNT=0`.
+
 [[post-update]]
 post-update
 ~~~~~~~~~~~
diff --git a/Documentation/technical/pack-protocol.txt b/Documentation/technical/pack-protocol.txt
index 8b36343802..7a2ed30cfc 100644
--- a/Documentation/technical/pack-protocol.txt
+++ b/Documentation/technical/pack-protocol.txt
@@ -454,7 +454,8 @@ The reference discovery phase is done nearly the same way as it is in the
 fetching protocol. Each reference obj-id and name on the server is sent
 in packet-line format to the client, followed by a flush-pkt.  The only
 real difference is that the capability listing is different - the only
-possible values are 'report-status', 'delete-refs' and 'ofs-delta'.
+possible values are 'report-status', 'delete-refs', 'ofs-delta' and
+'push-options'.
 
 Reference Update Request and Packfile Transfer
 ----------------------------------------------
@@ -465,9 +466,10 @@ that it wants to update, it sends a line listing the obj-id currently on
 the server, the obj-id the client would like to update it to and the name
 of the reference.
 
-This list is followed by a flush-pkt and then the packfile that should
-contain all the objects that the server will need to complete the new
-references.
+This list is followed by a flush-pkt. Then the push options are transmitted
+one per packet followed by another flush-pkt. After that the packfile that
+should contain all the objects that the server will need to complete the new
+references will be sent.
 
 ----
   update-request    =  *shallow ( command-list | push-cert ) [packfile]
diff --git a/Documentation/technical/protocol-capabilities.txt b/Documentation/technical/protocol-capabilities.txt
index eaab6b4ac7..4c28d3a8ae 100644
--- a/Documentation/technical/protocol-capabilities.txt
+++ b/Documentation/technical/protocol-capabilities.txt
@@ -253,6 +253,15 @@ atomic pushes. If the pushing client requests this capability, the server
 will update the refs in one atomic transaction. Either all refs are
 updated or none.
 
+push-options
+------------
+
+If the server sends the 'push-options' capability it is able to accept
+push options after the update commands have been sent, but before the
+packfile is streamed. If the pushing client requests this capability,
+the server will pass the options to the pre- and post- receive hooks
+that process this push request.
+
 allow-tip-sha1-in-want
 ----------------------