[PATCH] dim: set magic fdo cookie push-option on git push

[Jani Nikula]

Make it possible for the server side git pre-receive hook to determine
the client is dim and refuse the push otherwise.

Obviously it's possible to set the push-option manually on the git
command line as well, but there's really no plausible denial in that
case.

Cc: Daniel Stone <daniel at fooishbar.org>
Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
Cc: Emil Velikov <emil.l.velikov at gmail.com>
Signed-off-by: Jani Nikula <jani.nikula at intel.com>
---
 dim | 26 ++++++++++++++------------
 1 file changed, 14 insertions(+), 12 deletions(-)

diff --git a/dim b/dim
index a71c5f23d35c..f1b43552cb59 100755
--- a/dim
+++ b/dim
@@ -76,6 +76,8 @@ dim=$(basename $0)
 dim_today=$(date +%Y-%m-%d)
 dim_timestamp="$(date --utc +%Yy-%mm-%dd-%Hh-%Mm-%Ss) UTC"
 
+dim_fdo_cookie="--push-option fdo.pushedWithDim=this-was-pushed-with-dim-and-not-manually"
+
 maintainer_tools_https=https://gitlab.freedesktop.org/drm/maintainer-tools.git
 
 # Recipients for all dim based pull requests.
@@ -529,14 +531,14 @@ function update_linux_next # branch next next-fixes fixes
 
 	# always update drm-intel-fixes
 	echo -n "Pushing $linux_fixes to for-linux-next-fixes... "
-	git push $DRY_RUN $remote +$remote/$linux_fixes:for-linux-next-fixes # >& /dev/null
+	git push $dim_fdo_cookie $DRY_RUN $remote +$remote/$linux_fixes:for-linux-next-fixes # >& /dev/null
 	echo "Done."
 
 	if git merge-base --is-ancestor $remote/$linux_next_fixes $remote/$linux_fixes ; then
 		# -fixes has caught up to dinf, i.e. we're out of the merge
 		# window. Push the next queue.
 		echo -n "Out of merge window. Pushing $linux_next to for-linux-next... "
-		git push $DRY_RUN $remote +$remote/$linux_next:for-linux-next >& /dev/null
+		git push $dim_fdo_cookie $DRY_RUN $remote +$remote/$linux_next:for-linux-next >& /dev/null
 		echo "Done."
 	else
 		# dinf is ahead of -fixes, i.e. drm-next has already closed for
@@ -544,7 +546,7 @@ function update_linux_next # branch next next-fixes fixes
 		# for the current -next cycle. Push dinf
 
 		echo -n "Pushing $linux_next_fixes to for-linux-next... "
-		git push $DRY_RUN $remote +$remote/$linux_next_fixes:for-linux-next >& /dev/null
+		git push $dim_fdo_cookie $DRY_RUN $remote +$remote/$linux_next_fixes:for-linux-next >& /dev/null
 		echo "Done."
 	fi
 }
@@ -655,7 +657,7 @@ function commit_rerere_cache
 	rm $commit_message
 
 	echo -n "Pushing rerere cache... "
-	git push $DRY_RUN $remote HEAD >& /dev/null && echo "Done."
+	git push $dim_fdo_cookie $DRY_RUN $remote HEAD >& /dev/null && echo "Done."
 }
 
 function fetch_all
@@ -790,7 +792,7 @@ function dim_rebuild_tip
 	remote=$(repo_to_remote drm-tip)
 
 	echo -n "Pushing $integration_branch... "
-	git push $DRY_RUN $remote +HEAD >& /dev/null && echo "Done."
+	git push $dim_fdo_cookie $DRY_RUN $remote +HEAD >& /dev/null && echo "Done."
 
 	commit_rerere_cache
 }
@@ -979,7 +981,7 @@ function dim_push_branch
 		fi
 	fi
 
-	git push $DRY_RUN $remote $branch "$@"
+	git push $dim_fdo_cookie $DRY_RUN $remote $branch "$@"
 
 	update_linux_next $branch drm-intel-next-queued drm-intel-next-fixes drm-intel-fixes
 	update_linux_next $branch drm-misc-next drm-misc-next-fixes drm-misc-fixes
@@ -1505,7 +1507,7 @@ function dim_create_branch
 
 	# git push gives confusing error messages for non-existing branches,
 	# even with --dry-run, hence the even quieter $DRY
-	$DRY git push $remote +$branch --set-upstream
+	$DRY git push $dim_fdo_cookie $remote +$branch --set-upstream
 
 	cd $DIM_PREFIX/drm-rerere
 	$DRY sed -i "s/^\() # DO NOT CHANGE THIS LINE\)$/\t\"$repo\t\t${branch//\//\\\/}\"\n\1/" $dim_integration_config
@@ -1542,7 +1544,7 @@ function dim_remove_branch
 
 	remote=$(repo_to_remote $repo)
 
-	git push $DRY_RUN $remote --delete $branch
+	git push $dim_fdo_cookie $DRY_RUN $remote --delete $branch
 	$DRY git fetch $remote --prune
 	cd $DIM_PREFIX/drm-rerere
 	$DRY sed -i "/^[[:space:]]*\"${repo}[[:space:]]\+${branch//\//\\\/}.*$/d" $dim_integration_config
@@ -1997,11 +1999,11 @@ function dim_update_next_continue
 
 	remote=$(repo_to_remote drm-intel)
 
-	git push $DRY_RUN -f $remote drm-intel-next-queued:drm-intel-next
+	git push $dim_fdo_cookie $DRY_RUN -f $remote drm-intel-next-queued:drm-intel-next
 	tag=$(tag_name "drm-intel-next")
 
 	tag_branch $tag drm-intel-next
-	git push $DRY_RUN $remote $tag
+	git push $dim_fdo_cookie $DRY_RUN $remote $tag
 }
 
 function dim_tag_branch
@@ -2036,7 +2038,7 @@ function dim_tag_branch
 
 	tag=$(tag_name "$branch")
 	tag_branch $tag $branch
-	git push $DRY_RUN $remote $tag
+	git push $dim_fdo_cookie $DRY_RUN $remote $tag
 }
 
 function dim_tag_next
@@ -2074,7 +2076,7 @@ function dim_pull_request
 		tag=$(tag_name "$branch")
 		gitk --first-parent "$branch" ^$upstream &
 		tag_branch $tag $branch
-		$DRY git push $remote $tag
+		$DRY git push $dim_fdo_cookie $remote $tag
 		prep_pull_mail $req_file $tag
 
 		repo=$(branch_to_repo $branch)
-- 
2.20.1