Even though multiplication is commutative, the order of arguments
should be xcalloc(nmemb, size). ps_matched is an array of 1-byte
element whose size is the same as the number of pathspec elements.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Update to the "linked checkout" in 2.5.0-rc1.
Instead of "checkout --to" that does not do what "checkout"
normally does, move the functionality to "git worktree add".
* es/worktree-add: (24 commits)
Revert "checkout: retire --ignore-other-worktrees in favor of --force"
checkout: retire --ignore-other-worktrees in favor of --force
worktree: add: auto-vivify new branch when <branch> is omitted
worktree: add: make -b/-B default to HEAD when <branch> is omitted
worktree: extract basename computation to new function
checkout: require worktree unconditionally
checkout: retire --to option
tests: worktree: retrofit "checkout --to" tests for "worktree add"
worktree: add -b/-B options
worktree: add --detach option
worktree: add --force option
worktree: introduce "add" command
checkout: drop 'checkout_opts' dependency from prepare_linked_checkout
checkout: make --to unconditionally verbose
checkout: prepare_linked_checkout: drop now-unused 'new' argument
checkout: relocate --to's "no branch specified" check
checkout: fix bug with --to and relative HEAD
Documentation/git-worktree: add EXAMPLES section
Documentation/git-worktree: add high-level 'lock' overview
Documentation/git-worktree: split technical info from general description
...
"git checkout [<tree-ish>] <paths>" spent unnecessary cycles
checking if the current branch was checked out elsewhere, when we
know we are not switching the branches ourselves.
* nd/multiple-work-trees:
worktree: new place for "git prune --worktrees"
checkout: don't check worktrees when not necessary
This reverts commit 0d1a151783.
When trying to switch to a different branch, that happens to be
checked out in another working tree, the user shouldn't have to
give up the other safety measures (like protecting the local changes
that overlap the difference between the branches) while defeating
the "no two checkouts of the same branch" safety.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
As a safeguard, checking out a branch already checked out by a different
worktree is disallowed. This behavior can be overridden with
--ignore-other-worktrees, however, this option is neither obvious nor
particularly discoverable. As a common safeguard override, --force is
more likely to come to mind. Therefore, overload it to also suppress the
check for a branch already checked out elsewhere.
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In order to allow linked worktree creation via "git checkout --to" from
a bare repository, 3473ad0 (checkout: don't require a work tree when
checking out into a new one, 2014-11-30) dropped git-checkout's
unconditional NEED_WORK_TREE requirement and instead performed worktree
setup conditionally based upon presence or absence of the --to option.
Now that --to has been retired and git-checkout is no longer responsible
for linked worktree creation, the NEED_WORK_TREE requirement can be
re-instated.
This effectively reverts 3473ad0, except for the tests it added which
now check bare repository behavior of "git worktree add" instead.
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Now that "git worktree add" has achieved user-facing feature-parity with
"git checkout --to", retire the latter.
Move the actual linked worktree creation functionality,
prepare_linked_checkout() and its helpers, verbatim from checkout.c to
worktree.c.
This effectively reverts changes to checkout.c by 529fef2 (checkout:
support checking out into a new working directory, 2014-11-30) with the
exception of merge_working_tree() and switch_branches() which still
require specialized knowledge that a the checkout is occurring in a
newly-created linked worktree (signaled to them by the private
GIT_CHECKOUT_NEW_WORKTREE environment variable).
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The plan is to relocate "git checkout --to" functionality to "git
worktree add", however, worktree.c won't have access to the 'struct
checkout_opts' passed to prepare_linked_worktree(), which it consults
for the pathname of the new worktree and the argv[] of the command it
should run to populate the new worktree. Facilitate relocation of
prepare_linked_worktree() by instead having it accept the pathname and
argv[] directly, thus eliminating the final references to 'struct
checkout_opts'.
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
prepare_linked_checkout() respects git-checkout's --quiet flag, however,
the plan is to relocate "git checkout --to" functionality to "git
worktree add", and git-worktree does not (yet) have a --quiet flag.
Consequently, make prepare_linked_checkout() unconditionally verbose to
ease eventual code movement to worktree.c.
(A --quiet flag can be added to git-worktree later if there is demand
for it.)
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The only references to 'new' were folded out by the last two patches.
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The plan is to relocate "git checkout --to" functionality to "git
worktree add", however, this check expects a 'struct branch_info' which
git-worktree won't have at hand. It will, however, have access to its
own command-line from which it can pick up the branch name. Therefore,
as a preparatory step, rather than having prepare_linked_checkout()
perform this check, make it the caller's responsibility.
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Given "git checkout --to <path> HEAD~1", the new worktree's HEAD should
begin life at the current branch's HEAD~1, however, it actually ends up
at HEAD~2. This happens because:
1. git-checkout resolves HEAD~1
2. to satisfy is_git_directory(), prepare_linked_worktree() creates
a HEAD for the new worktree with the value of the resolved HEAD~1
3. git-checkout re-invokes itself with the same arguments within the
new worktree to populate the worktree
4. the sub git-checkout resolves HEAD~1 relative to its own HEAD,
which is the resolved HEAD~1 from the original invocation,
resulting unexpectedly and incorrectly in HEAD~2 (relative to the
original)
Fix this by unconditionally assigning the current worktree's HEAD as the
value of the new worktree's HEAD.
As a side-effect, this change also eliminates a dependence within
prepare_linked_checkout() upon 'struct branch_info'. The plan is to
eventually relocate "git checkout --to" functionality to "git worktree
add", and worktree.c won't have knowledge of 'struct branch_info', so
removal of this dependency is a step toward that goal.
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When --patch or pathspecs are passed to git checkout, the working tree
will not be switching branch, so there's no need to check if the branch
that we are running checkout on is already checked out.
Original-patch-by: Spencer Baugh <sbaugh@catern.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change typedef each_ref_fn to take a "const struct object_id *oid"
parameter instead of "const unsigned char *sha1".
To aid this transition, implement an adapter that can be used to wrap
old-style functions matching the old typedef, which is now called
"each_ref_sha1_fn"), and make such functions callable via the new
interface. This requires the old function and its cb_data to be
wrapped in a "struct each_ref_fn_sha1_adapter", and that object to be
used as the cb_data for an adapter function, each_ref_fn_adapter().
This is an enormous diff, but most of it consists of simple,
mechanical changes to the sites that call any of the "for_each_ref"
family of functions. Subsequent to this change, the call sites can be
rewritten one by one to use the new interface.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A replacement for contrib/workdir/git-new-workdir that does not
rely on symbolic links and make sharing of objects and refs safer
by making the borrowee and borrowers aware of each other.
* nd/multiple-work-trees: (41 commits)
prune --worktrees: fix expire vs worktree existence condition
t1501: fix test with split index
t2026: fix broken &&-chain
t2026 needs procondition SANITY
git-checkout.txt: a note about multiple checkout support for submodules
checkout: add --ignore-other-wortrees
checkout: pass whole struct to parse_branchname_arg instead of individual flags
git-common-dir: make "modules/" per-working-directory directory
checkout: do not fail if target is an empty directory
t2025: add a test to make sure grafts is working from a linked checkout
checkout: don't require a work tree when checking out into a new one
git_path(): keep "info/sparse-checkout" per work-tree
count-objects: report unused files in $GIT_DIR/worktrees/...
gc: support prune --worktrees
gc: factor out gc.pruneexpire parsing code
gc: style change -- no SP before closing parenthesis
checkout: clean up half-prepared directories in --to mode
checkout: reject if the branch is already checked out elsewhere
prune: strategies for linked checkouts
checkout: support checking out into a new working directory
...
When detached and checking out a branch again, git checkout warns
about commit(s) that might get lost. It says "If you want to keep
them ..." even for only one commit.
Use Q_() to allow differentiating singular vs plural.
Signed-off-by: Thomas Schneider <thosch97@gmail.com>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This patch puts the usage info strings that were not already in docopt-
like format into docopt-like format, which will be a litle easier for
end users and a lot easier for translators. Changes include:
- Placing angle brackets around fill-in-the-blank parameters
- Putting dashes in multiword parameter names
- Adding spaces to [-f|--foobar] to make [-f | --foobar]
- Replacing <foobar>* with [<foobar>...]
Signed-off-by: Alex Henrie <alexhenrie24@gmail.com>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Noticed-by: Mark Levedahl <mlevedahl@gmail.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git ls-tree" does not support path selection based on negative
pathspecs, but did not error out when negative pathspecs are given.
* nd/ls-tree-pathspec:
t3102: style modernization
t3102: document that ls-tree does not yet support negated pathspec
ls-tree: disable negative pathspec because it's not supported
ls-tree: remove path filtering logic in show_tree
tree.c: update read_tree_recursive callback to pass strbuf as base
"git checkout $treeish $path", when $path in the index and the
working tree already matched what is in $treeish at the $path,
still overwrote the $path unnecessarily.
* jk/checkout-from-tree:
checkout $tree: do not throw away unchanged index entries
This allows the callback to use 'base' as a temporary buffer to
quickly assemble full path "without" extra allocation. The callback
has to restore it afterwards of course.
Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Non-recursive checkout creates empty directpries in place of submodules.
If then I try to "checkout --to" submodules there, it refuses to do so,
because directory already exists.
Fix by allowing checking out to empty directory. Add test and modify the
existing one so that it uses non-empty directory.
Signed-off-by: Max Kirillov <max@max630.net>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
For normal use cases, it does not make sense for 'checkout' to work on
a bare repository, without a worktree. But "checkout --to" is an
exception because it _creates_ a new worktree. Allow this option to
run on bare repositories.
People who check out from a bare repository should remember that
core.logallrefupdates is off by default and it should be turned back
on. `--to` cannot do this automatically behind the user's back because
some user may deliberately want no reflog.
For people interested in repository setup/discovery code,
is_bare_repository_cfg (aka "core.bare") is unchanged by this patch,
which means 'true' by default for bare repos. Fortunately when we get
the repo through a linked checkout, is_bare_repository_cfg is never
used. So all is still good.
[nd: commit message]
Signed-off-by: Dennis Kaarsemaker <dennis@kaarsemaker.net>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
One branch obviously can't be checked out at two places (but detached
heads are ok). Give the user a choice in this case: --detach, -b
new-branch, switch branch in the other checkout first or simply 'cd'
and continue to work there.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
(alias R=$GIT_COMMON_DIR/worktrees/<id>)
- linked checkouts are supposed to keep its location in $R/gitdir up
to date. The use case is auto fixup after a manual checkout move.
- linked checkouts are supposed to update mtime of $R/gitdir. If
$R/gitdir's mtime is older than a limit, and it points to nowhere,
worktrees/<id> is to be pruned.
- If $R/locked exists, worktrees/<id> is not supposed to be pruned. If
$R/locked exists and $R/gitdir's mtime is older than a really long
limit, warn about old unused repo.
- "git checkout --to" is supposed to make a hard link named $R/link
pointing to the .git file on supported file systems to help detect
the user manually deleting the checkout. If $R/link exists and its
link count is greated than 1, the repo is kept.
Helped-by: Marc Branchaud <marcnarc@xiplink.com>
Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Helped-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Marc Branchaud <marcnarc@xiplink.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git checkout --to" sets up a new working directory with a .git file
pointing to $GIT_DIR/worktrees/<id>. It then executes "git checkout"
again on the new worktree with the same arguments except "--to" is
taken out. The second checkout execution, which is not contaminated
with any info from the current repository, will actually check out and
everything that normal "git checkout" does.
Helped-by: Marc Branchaud <marcnarc@xiplink.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In the previous patch, git_snpath() is modified to allocate a new
strbuf buffer because vsnpath() needs that. But that makes it
awkward because git_snpath() receives a pre-allocated buffer from
outside and has to copy data back. Rename it to strbuf_git_path()
and make it receive strbuf directly.
Using git_path() in update_refs_for_switch() which used to call
git_snpath() is safe because that function and all of its callers do
not keep any pointer to the round-robin buffer pool allocated by
get_pathname().
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Before the previous commit, get_pathname returns an array of PATH_MAX
length. Even if git_path() and similar functions does not use the
whole array, git_path() caller can, in theory.
After the commit, get_pathname() may return a buffer that has just
enough room for the returned string and git_path() caller should never
write beyond that.
Make git_path(), mkpath() and git_path_submodule() return a const
buffer to make sure callers do not write in it at all.
This could have been part of the previous commit, but the "const"
conversion is too much distraction from the core changes in path.c.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we "git checkout $tree", we pull paths from $tree into
the index, and then check the resulting entries out to the
worktree. Our method for the first step is rather
heavy-handed, though; it clobbers the entire existing index
entry, even if the content is the same. This means we lose
our stat information, leading checkout_entry to later
rewrite the entire file with identical content.
Instead, let's see if we have the identical entry already in
the index, in which case we leave it in place. That lets
checkout_entry do the right thing. Our tests cover two
interesting cases:
1. We make sure that a file which has no changes is not
rewritten.
2. We make sure that we do update a file that is unchanged
in the index (versus $tree), but has working tree
changes. We keep the old index entry, and
checkout_entry is able to realize that our stat
information is out of date.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
resolve_ref_unsafe takes a boolean argument for reading (a nonexistent ref
resolves successfully for writing but not for reading). Change this to be
a flags field instead, and pass the new constant RESOLVE_REF_READING when
we want this behaviour.
While at it, swap two of the arguments in the function to put output
arguments at the end. As a nice side effect, this ensures that we can
catch callers that were unaware of the new API so they can be audited.
Give the wrapper functions resolve_refdup and read_ref_full the same
treatment for consistency.
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Continue where ae021d87 (use skip_prefix to avoid magic numbers) left off
and use skip_prefix() in more places for determining the lengths of prefix
strings to avoid using dependent constants and other indirect methods.
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move the interface declaration for the functions in lockfile.c from
cache.h to a new file, lockfile.h. Add #includes where necessary (and
remove some redundant includes of cache.h by files that already
include builtin.h).
Move the documentation of the lock_file state diagram from lockfile.c
to the new header file.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a few more places in "commit" and "checkout" that make sure
that the cache-tree is fully populated in the index.
* dt/cache-tree-repair:
cache-tree: do not try to use an invalidated subtree info to build a tree
cache-tree: Write updated cache-tree after commit
cache-tree: subdirectory tests
test-dump-cache-tree: invalid trees are not errors
cache-tree: create/update cache-tree on checkout
An experiment to use two files (the base file and incremental
changes relative to it) to represent the index to reduce I/O cost
of rewriting a large index when only small part of the working tree
changes.
* nd/split-index: (32 commits)
t1700: new tests for split-index mode
t2104: make sure split index mode is off for the version test
read-cache: force split index mode with GIT_TEST_SPLIT_INDEX
read-tree: note about dropping split-index mode or index version
read-tree: force split-index mode off on --index-output
rev-parse: add --shared-index-path to get shared index path
update-index --split-index: do not split if $GIT_DIR is read only
update-index: new options to enable/disable split index mode
split-index: strip pathname of on-disk replaced entries
split-index: do not invalidate cache-tree at read time
split-index: the reading part
split-index: the writing part
read-cache: mark updated entries for split index
read-cache: save deleted entries in split index
read-cache: mark new entries for split index
read-cache: split-index mode
read-cache: save index SHA-1 after reading
entry.c: update cache_changed if refresh_cache is set in checkout_entry()
cache-tree: mark istate->cache_changed on prime_cache_tree()
cache-tree: mark istate->cache_changed on cache tree update
...
When git checkout checks out a branch, create or update the
cache-tree so that subsequent operations are faster.
update_main_cache_tree learned a new flag, WRITE_TREE_REPAIR. When
WRITE_TREE_REPAIR is set, portions of the cache-tree which do not
correspond to existing tree objects are invalidated (and portions which
do are marked as valid). No new tree objects are created.
Signed-off-by: David Turner <dturner@twitter.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It's a common idiom to match a prefix and then skip past it
with strlen, like:
if (starts_with(foo, "bar"))
foo += strlen("bar");
This avoids magic numbers, but means we have to repeat the
string (and there is no compiler check that we didn't make a
typo in one of the strings).
We can use skip_prefix to handle this case without repeating
ourselves.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Other fill_stat_cache_info() is on new entries, which should set
CE_ENTRY_ADDED in cache_changed, so we're safe.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Update "update-ref --stdin [-z]" and then introduce a transactional
support for (multi-)reference updates.
* mh/ref-transaction: (27 commits)
ref_transaction_commit(): work with transaction->updates in place
struct ref_update: add a type field
struct ref_update: add a lock field
ref_transaction_commit(): simplify code using temporary variables
struct ref_update: store refname as a FLEX_ARRAY
struct ref_update: rename field "ref_name" to "refname"
refs: remove API function update_refs()
update-ref --stdin: reimplement using reference transactions
refs: add a concept of a reference transaction
update-ref --stdin: harmonize error messages
update-ref --stdin: improve the error message for unexpected EOF
t1400: test one mistake at a time
update-ref --stdin -z: deprecate interpreting the empty string as zeros
update-ref.c: extract a new function, parse_next_sha1()
t1400: test that stdin -z update treats empty <newvalue> as zeros
update-ref --stdin: simplify error messages for missing oldvalues
update-ref --stdin: make error messages more consistent
update-ref --stdin: improve error messages for invalid values
update-ref.c: extract a new function, parse_refname()
parse_cmd_verify(): copy old_sha1 instead of evaluating <oldvalue> twice
...
Change checkout.c to check if a ref exists instead of checking if a loose ref
file exists when deciding if to delete an orphaned log file. Otherwise, if a
ref only exists as a packed ref without a corresponding loose ref for the
currently checked out branch, we risk that the reflog will be deleted when we
switch to a different branch.
Update the reflog tests to check for this bug.
The following reproduces the bug:
$ git init-db
$ git config core.logallrefupdates true
$ git commit -m Initial --allow-empty
[master (root-commit) bb11abe] Initial
$ git reflog master
[8561dcb master@{0}: commit (initial): Initial]
$ find .git/{refs,logs} -type f | grep master
[.git/refs/heads/master]
[.git/logs/refs/heads/master]
$ git branch foo
$ git pack-refs --all
$ find .git/{refs,logs} -type f | grep master
[.git/logs/refs/heads/master]
$ git checkout foo
$ find .git/{refs,logs} -type f | grep master
... reflog file is missing ...
$ git reflog master
... nothing ...
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Acked-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add two new functions, reflog_exists and delete_reflog, to hide the internal
reflog implementation (that they are files under .git/logs/...) from callers.
Update checkout.c to use these functions in update_refs_for_switch instead of
building pathnames and calling out to file access functions. Update reflog.c
to use these to check if the reflog exists. Now there are still many places
in reflog.c where we are still leaking the reflog storage implementation but
this at least reduces the number of such dependencies by one. Finally
change two places in refs.c itself to use the new function to check if a ref
exists or not isntead of build-path-and-stat(). Now, this is strictly not all
that important since these are in parts of refs that are implementing the
actual file storage backend but on the other hand it will not hurt either.
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Acked-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Eradicate mistaken use of "nor" (that is, essentially "nor" used
not in "neither A nor B" ;-)) from in-code comments, command output
strings, and documentations.
* jl/nor-or-nand-and:
code and test: fix misuses of "nor"
comments: fix misuses of "nor"
contrib: fix misuses of "nor"
Documentation: fix misuses of "nor"
Make sure that the help text given to describe the "<param>" part
of the "git cmd --option=<param>" does not contain SP or _,
e.g. "--gpg-sign=<key-id>" option for "git commit" is not spelled
as "--gpg-sign=<key id>".
* jc/rev-parse-argh-dashed-multi-words:
parse-options: make sure argh string does not have SP or _
update-index: teach --cacheinfo a new syntax "mode,sha1,path"
parse-options: multi-word argh should use dash to separate words
Given that these constants are only being used when updating
references, it is inappropriate to give them such generic names as
"DIE_ON_ERR". So prefix their names with "UPDATE_REFS_".
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>