All refs under `refs/pull` should only be changed from Gitea inside but
not by pushing from outside of Gitea.
This PR will prevent the pull refs update but allow other refs to be
updated on the same pushing with `--mirror` operations.
The main changes are to add checks on `update` hook but not
`pre-receive` because `update` will be invoked by every ref but
`pre-receive` will revert all changes once one ref update fails.
Agit returned result should be from `ProcReceive` hook but not
`PostReceive` hook. Then for all non-agit pull requests, it will not
check the pull requests for every pushing `refs/pull/%d/head`.
Regression of #29493. If a branch has been deleted, repushing it won't
restore it.
Lunny may have noticed that, but I didn't delve into the comment then
overlooked it:
https://github.com/go-gitea/gitea/pull/29493#discussion_r1509046867
The additional comments added are to explain the issue I found during
testing, which are unrelated to the fixes.
Unlike other async processing in the queue, we should sync branches to
the DB immediately when handling git hook calling. If it fails, users
can see the error message in the output of the git command.
It can avoid potential inconsistency issues, and help #29494.
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Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
