mirror of
https://github.com/git/git
synced 2024-08-25 02:35:46 +00:00
![Shawn Pearce](/assets/img/avatar_default.png)
This conversion also adds the '-m' switch to update-ref allowing the caller to record why the ref is changing. At present this is merely copied down into the ref_lock API. Signed-off-by: Shawn O. Pearce <spearce@spearce.org> Signed-off-by: Junio C Hamano <junkio@cox.net>
59 lines
1.8 KiB
Plaintext
59 lines
1.8 KiB
Plaintext
git-update-ref(1)
|
|
=================
|
|
|
|
NAME
|
|
----
|
|
git-update-ref - update the object name stored in a ref safely
|
|
|
|
SYNOPSIS
|
|
--------
|
|
'git-update-ref' <ref> <newvalue> [<oldvalue>] [-m <reason>]
|
|
|
|
DESCRIPTION
|
|
-----------
|
|
Given two arguments, stores the <newvalue> in the <ref>, possibly
|
|
dereferencing the symbolic refs. E.g. `git-update-ref HEAD
|
|
<newvalue>` updates the current branch head to the new object.
|
|
|
|
Given three arguments, stores the <newvalue> in the <ref>,
|
|
possibly dereferencing the symbolic refs, after verifying that
|
|
the current value of the <ref> matches <oldvalue>.
|
|
E.g. `git-update-ref refs/heads/master <newvalue> <oldvalue>`
|
|
updates the master branch head to <newvalue> only if its current
|
|
value is <oldvalue>.
|
|
|
|
It also allows a "ref" file to be a symbolic pointer to another
|
|
ref file by starting with the four-byte header sequence of
|
|
"ref:".
|
|
|
|
More importantly, it allows the update of a ref file to follow
|
|
these symbolic pointers, whether they are symlinks or these
|
|
"regular file symbolic refs". It follows *real* symlinks only
|
|
if they start with "refs/": otherwise it will just try to read
|
|
them and update them as a regular file (i.e. it will allow the
|
|
filesystem to follow them, but will overwrite such a symlink to
|
|
somewhere else with a regular filename).
|
|
|
|
In general, using
|
|
|
|
git-update-ref HEAD "$head"
|
|
|
|
should be a _lot_ safer than doing
|
|
|
|
echo "$head" > "$GIT_DIR/HEAD"
|
|
|
|
both from a symlink following standpoint *and* an error checking
|
|
standpoint. The "refs/" rule for symlinks means that symlinks
|
|
that point to "outside" the tree are safe: they'll be followed
|
|
for reading but not for writing (so we'll never write through a
|
|
ref symlink to some other tree, if you have copied a whole
|
|
archive by creating a symlink tree).
|
|
|
|
Author
|
|
------
|
|
Written by Linus Torvalds <torvalds@osdl.org>.
|
|
|
|
GIT
|
|
---
|
|
Part of the gitlink:git[7] suite
|