Commit Graph

592 Commits

Author SHA1 Message Date
Junio C Hamano
4d5c4e498a Merge branch 'mh/reflog-expire'
Restructure "reflog expire" to fit the reflogs better with the
recently updated ref API.

Looked reasonable (except that some shortlog entries stood out like
a sore thumb).

* mh/reflog-expire: (24 commits)
  refs.c: let fprintf handle the formatting
  refs.c: don't expose the internal struct ref_lock in the header file
  lock_any_ref_for_update(): inline function
  refs.c: remove unlock_ref/close_ref/commit_ref from the refs api
  reflog_expire(): new function in the reference API
  expire_reflog(): treat the policy callback data as opaque
  Move newlog and last_kept_sha1 to "struct expire_reflog_cb"
  expire_reflog(): move rewrite to flags argument
  expire_reflog(): move verbose to flags argument
  expire_reflog(): pass flags through to expire_reflog_ent()
  struct expire_reflog_cb: a new callback data type
  Rename expire_reflog_cb to expire_reflog_policy_cb
  expire_reflog(): move updateref to flags argument
  expire_reflog(): move dry_run to flags argument
  expire_reflog(): add a "flags" argument
  expire_reflog(): extract two policy-related functions
  Extract function should_expire_reflog_ent()
  expire_reflog(): use a lock_file for rewriting the reflog file
  expire_reflog(): return early if the reference has no reflog
  expire_reflog(): rename "ref" parameter to "refname"
  ...
2015-02-11 13:43:38 -08:00
Junio C Hamano
092c4be7f5 Merge branch 'jk/blame-commit-label'
"git blame HEAD -- missing" failed to correctly say "HEAD" when it
tried to say "No such path 'missing' in HEAD".

* jk/blame-commit-label:
  blame.c: fix garbled error message
  use xstrdup_or_null to replace ternary conditionals
  builtin/commit.c: use xstrdup_or_null instead of envdup
  builtin/apply.c: use xstrdup_or_null instead of null_strdup
  git-compat-util: add xstrdup_or_null helper
2015-02-11 13:39:50 -08:00
Jeff King
8c53f0719b use xstrdup_or_null to replace ternary conditionals
This replaces "x ? xstrdup(x) : NULL" with xstrdup_or_null(x).
The change is fairly mechanical, with the exception of
resolve_refdup, which can eliminate a temporary variable.

There are still a few hits grepping for "?.*xstrdup", but
these are of slightly different forms and cannot be
converted (e.g., "x ? xstrdup(x->foo) : NULL").

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-01-13 10:05:48 -08:00
René Scharfe
33adc83ddb refs: plug strbuf leak in lock_ref_sha1_basic()
Don't just reset, but release the resource held by the local
variable that is about to go out of scope.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-29 13:14:16 -08:00
Junio C Hamano
aa9066fccd Merge branch 'jk/read-packed-refs-without-path-max'
Git did not correctly read an overlong refname from a packed refs
file.

* jk/read-packed-refs-without-path-max:
  read_packed_refs: use skip_prefix instead of static array
  read_packed_refs: pass strbuf to parse_ref_line
  read_packed_refs: use a strbuf for reading lines
2014-12-22 12:28:04 -08:00
Junio C Hamano
6f3abb7a87 Merge branch 'jk/for-each-reflog-ent-reverse'
The code that reads the reflog from the newer to the older entries
did not handle an entry that crosses a boundary of block it uses to
read them correctly.

* jk/for-each-reflog-ent-reverse:
  for_each_reflog_ent_reverse: turn leftover check into assertion
  for_each_reflog_ent_reverse: fix newlines on block boundaries
2014-12-22 12:27:32 -08:00
Junio C Hamano
a7ddaa8eac Merge branch 'mh/simplify-repack-without-refs'
"git remote update --prune" to drop many refs has been optimized.

* mh/simplify-repack-without-refs:
  sort_string_list(): rename to string_list_sort()
  prune_remote(): iterate using for_each_string_list_item()
  prune_remote(): rename local variable
  repack_without_refs(): make the refnames argument a string_list
  prune_remote(): sort delete_refs_list references en masse
  prune_remote(): initialize both delete_refs lists in a single loop
  prune_remote(): exit early if there are no stale references
2014-12-22 12:26:50 -08:00
Stefan Beller
c653e0343d refs.c: let fprintf handle the formatting
Instead of calculating whether to put a plus or minus sign, offload
the responsibilty to the fprintf function.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-22 10:13:16 -08:00
Stefan Beller
3581d79335 refs.c: don't expose the internal struct ref_lock in the header file
Now the struct ref_lock is used completely internally, so let's
remove it from the header file.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-22 10:13:15 -08:00
Michael Haggerty
31e07f76a9 lock_any_ref_for_update(): inline function
Inline the function at its one remaining caller (which is within
refs.c) and remove it.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-22 10:13:15 -08:00
Ronnie Sahlberg
0b1e654801 refs.c: remove unlock_ref/close_ref/commit_ref from the refs api
unlock|close|commit_ref can be made static since there are no more external
callers.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-22 10:13:15 -08:00
Michael Haggerty
fa5b1830b0 reflog_expire(): new function in the reference API
Move expire_reflog() into refs.c and rename it to reflog_expire().
Turn the three policy functions into function pointers that are passed
into reflog_expire(). Add function prototypes and documentation to
refs.h.

[jc: squashed in $gmane/261582, drop "extern" in function definition]

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Reviewed-by: Stefan Beller <sbeller@google.com>
Tweaked-by: Ramsay Jones
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-22 10:11:40 -08:00
Ronnie Sahlberg
2c6207abbd refs.c: add a function to append a reflog entry to a fd
Break out the code to create the string and writing it to the file
descriptor from log_ref_write and add it into a dedicated function
log_ref_write_fd. It is a nice unit of work.

For now this is only used from log_ref_write, but in the future it
might have other callers.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-12 11:42:00 -08:00
Jeff King
ea417833ea read_packed_refs: use skip_prefix instead of static array
We want to recognize the packed-refs header and skip to the
"traits" part of the line. We currently do it by feeding
sizeof() a static const array to strncmp. However, it's a
bit simpler to just skip_prefix, which expresses the
intention more directly, and without remembering to account
for the NUL-terminator in each sizeof() call.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-10 09:40:33 -08:00
Jeff King
6a49870a72 read_packed_refs: pass strbuf to parse_ref_line
Now that we have a strbuf in read_packed_refs, we can pass
it straight to the line parser, which saves us an extra
strlen.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-10 09:28:54 -08:00
Jeff King
10c497aa0c read_packed_refs: use a strbuf for reading lines
Current code uses a fixed PATH_MAX-sized buffer for reading
packed-refs lines. This is a reasonable guess, in the sense
that git generally cannot work with refs larger than
PATH_MAX.  However, there are a few cases where it is not
great:

  1. Some systems may have a low value of PATH_MAX, but can
     actually handle larger paths in practice. Fixing this
     code path probably isn't enough to make them work
     completely with long refs, but it is a step in the
     right direction.

  2. We use fgets, which will happily give us half a line on
     the first read, and then the rest of the line on the
     second. This is probably OK in practice, because our
     refline parser is careful enough to look for the
     trailing newline on the first line. The second line may
     look like a peeled line to us, but since "^" is illegal
     in refnames, it is not likely to come up.

     Still, it does not hurt to be more careful.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-10 09:27:24 -08:00
Jeff King
69216bf72b for_each_reflog_ent_reverse: turn leftover check into assertion
Our loop should always process all lines, even if we hit the
beginning of the file. We have a conditional after the loop
ends to double-check that there is nothing left and to
process it. But this should never happen, and is a sign of a
logic bug in the loop. Let's turn it into a BUG assertion.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-05 11:11:52 -08:00
Jeff King
e5e73ff20b for_each_reflog_ent_reverse: fix newlines on block boundaries
When we read a reflog file in reverse, we read whole chunks
of BUFSIZ bytes, then loop over the buffer, parsing any
lines we find. We find the beginning of each line by looking
for the newline from the previous line. If we don't find
one, we know that we are either at the beginning of
the file, or that we have to read another block.

In the latter case, we stuff away what we have into a
strbuf, read another block, and continue our parse. But we
missed one case here. If we did find a newline, and it is at
the beginning of the block, we must also stuff that newline
into the strbuf, as it belongs to the block we are about to
read.

The minimal fix here would be to add this special case to
the conditional that checks whether we found a newline.
But we can make the flow a little clearer by rearranging a
bit: we first handle lines that we are going to show, and
then at the end of each loop, stuff away any leftovers if
necessary. That lets us fold this special-case in with the
more common "we ended in the middle of a line" case.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-05 11:11:35 -08:00
Ronnie Sahlberg
a785d3f77c refs.c: make ref_transaction_delete a wrapper for ref_transaction_update
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Reviewed-by: Michael Haggerty <mhagger@alum.mit.edu>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-04 15:39:37 -08:00
Ronnie Sahlberg
bc9f2925fb refs.c: make ref_transaction_create a wrapper for ref_transaction_update
The ref_transaction_update function can already be used to create refs by
passing null_sha1 as the old_sha1 parameter. Simplify by replacing
transaction_create with a thin wrapper.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Reviewed-by: Michael Haggerty <mhagger@alum.mit.edu>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-04 15:39:36 -08:00
Michael Haggerty
4a45b2f347 repack_without_refs(): make the refnames argument a string_list
Most of the callers have string_lists available already, whereas two
of them had to read data out of a string_list into an array of strings
just to call this function. So change repack_without_refs() to take
the list of refnames to omit as a string_list, and change the callers
accordingly.

Suggested-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-11-25 10:09:58 -08:00
Ronnie Sahlberg
068395150b lock_ref_sha1_basic: do not die on locking errors
lock_ref_sha1_basic is inconsistent about when it calls
die() and when it returns NULL to signal an error. This is
annoying to any callers that want to recover from a locking
error.

This seems to be mostly historical accident. It was added in
4bd18c4 (Improve abstraction of ref lock/write.,
2006-05-17), which returned an error in all cases except
calling safe_create_leading_directories, in which case it
died.  Later, 40aaae8 (Better error message when we are
unable to lock the index file, 2006-08-12) asked
hold_lock_file_for_update to die for us, leaving the
resolve_ref code-path the only one which returned NULL.

We tried to correct that in 5cc3cef (lock_ref_sha1(): do not
sometimes error() and sometimes die()., 2006-09-30),
by converting all of the die() calls into returns. But we
missed the "die" flag passed to the lock code, leaving us
inconsistent. This state persisted until e5c223e
(lock_ref_sha1_basic(): if locking fails with ENOENT, retry,
2014-01-18). Because of its retry scheme, it does not ask
the lock code to die, but instead manually dies with
unable_to_lock_die().

We can make this consistent with the other return paths by
converting this to use unable_to_lock_message(), and
returning NULL. This is safe to do because all callers
already needed to check the return value of the function,
since it could fail (and return NULL) for other reasons.

[jk: Added excessive history explanation]

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-11-20 08:25:03 -08:00
Junio C Hamano
a1671dd82b Merge branch 'jk/fetch-reflog-df-conflict'
Corner-case bugfixes for "git fetch" around reflog handling.

* jk/fetch-reflog-df-conflict:
  ignore stale directories when checking reflog existence
  fetch: load all default config at startup
2014-11-06 10:52:32 -08:00
Jeff King
9233887cce ignore stale directories when checking reflog existence
When we update a ref, we have two rules for whether or not
we actually update the reflog:

  1. If the reflog already exists, we will always append to
     it.

  2. If log_all_ref_updates is set, we will create a new
     reflog file if necessary.

We do the existence check by trying to open the reflog file,
either with or without O_CREAT (depending on log_all_ref_updates).
If it fails, then we check errno to see what happened.

If we were not using O_CREAT and we got ENOENT, the file
doesn't exist, and we return success (there isn't a reflog
already, and we were not told to make a new one).

If we get EISDIR, then there is likely a stale directory
that needs to be removed (e.g., there used to be "foo/bar",
it was deleted, and the directory "foo" was left. Now we
want to create the ref "foo"). If O_CREAT is set, then we
catch this case, try to remove the directory, and retry our
open. So far so good.

But if we get EISDIR and O_CREAT is not set, then we treat
this as any other error, which is not right. Like ENOENT,
EISDIR is an indication that we do not have a reflog, and we
should silently return success (we were not told to create
it). Instead, the current code reports this as an error, and
we fail to update the ref at all.

Note that this is relatively unlikely to happen, as you
would have to have had reflogs turned on, and then later
turned them off (it could also happen due to a bug in fetch,
but that was fixed in the previous commit). However, it's
quite easy to fix: we just need to treat EISDIR like ENOENT
for the non-O_CREAT case, and silently return (note that
this early return means we can also simplify the O_CREAT
case).

Our new tests cover both cases (O_CREAT and non-O_CREAT).
The first one already worked, of course.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-11-04 12:18:44 -08:00
Jonathan Nieder
65732845e8 ref_transaction_commit: bail out on failure to remove a ref
When removal of a loose or packed ref fails, bail out instead of
trying to finish the transaction.  This way, a single error message
can be printed (instead of multiple messages being concatenated by
mistake) and the operator can try to solve the underlying problem
before there is a chance to muck things up even more.

In particular, when git fails to remove a ref, git goes on to try to
delete the reflog.  Exiting early lets us keep the reflog.

When git succeeds in deleting a ref A and fails to remove a ref B, it
goes on to try to delete both reflogs.  It would be better to just
remove the reflog for A, but that would be a more invasive change.
Failing early means we keep both reflogs, which puts the operator in a
good position to understand the problem and recover.

A long term goal is to avoid these problems altogether and roll back
the transaction on failure.  That kind of transactionality will have
to wait for a later series (the plan for which is to make all
destructive work happen in a single update of the packed-refs file).

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Reviewed-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-15 10:47:27 -07:00
Jonathan Nieder
5a603b0463 refs.c: do not permit err == NULL
Some functions that take a strbuf argument to append an error treat
!err as an indication that the message should be suppressed (e.g.,
ref_update_reject_duplicates).  Others write the message to stderr on
!err (e.g., repack_without_refs).  Others crash (e.g.,
ref_transaction_update).

Some of these behaviors are for historical reasons and others were
accidents.  Luckily no callers pass err == NULL any more.  Simplify
by consistently requiring the strbuf argument.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Reviewed-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-15 10:47:26 -07:00
Ronnie Sahlberg
d0f810f0bc refs.c: allow listing and deleting badly named refs
We currently do not handle badly named refs well:

  $ cp .git/refs/heads/master .git/refs/heads/master.....@\*@\\.
  $ git branch
    fatal: Reference has invalid format: 'refs/heads/master.....@*@\.'
  $ git branch -D master.....@\*@\\.
    error: branch 'master.....@*@\.' not found.

Users cannot recover from a badly named ref without manually finding
and deleting the loose ref file or appropriate line in packed-refs.
Making that easier will make it easier to tweak the ref naming rules
in the future, for example to forbid shell metacharacters like '`'
and '"', without putting people in a state that is hard to get out of.

So allow "branch --list" to show these refs and allow "branch -d/-D"
and "update-ref -d" to delete them.  Other commands (for example to
rename refs) will continue to not handle these refs but can be changed
in later patches.

Details:

In resolving functions, refuse to resolve refs that don't pass the
git-check-ref-format(1) check unless the new RESOLVE_REF_ALLOW_BAD_NAME
flag is passed.  Even with RESOLVE_REF_ALLOW_BAD_NAME, refuse to
resolve refs that escape the refs/ directory and do not match the
pattern [A-Z_]* (think "HEAD" and "MERGE_HEAD").

In locking functions, refuse to act on badly named refs unless they
are being deleted and either are in the refs/ directory or match [A-Z_]*.

Just like other invalid refs, flag resolved, badly named refs with the
REF_ISBROKEN flag, treat them as resolving to null_sha1, and skip them
in all iteration functions except for for_each_rawref.

Flag badly named refs (but not symrefs pointing to badly named refs)
with a REF_BAD_NAME flag to make it easier for future callers to
notice and handle them specially.  For example, in a later patch
for-each-ref will use this flag to detect refs whose names can confuse
callers parsing for-each-ref output.

In the transaction API, refuse to create or update badly named refs,
but allow deleting them (unless they try to escape refs/ and don't match
[A-Z_]*).

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>
2014-10-15 10:47:26 -07:00
Jonathan Nieder
f3cc52d840 packed-ref cache: forbid dot-components in refnames
Since v1.7.9-rc1~10^2 (write_head_info(): handle "extra refs" locally,
2012-01-06), this trick to keep track of ".have" refs that are only
valid on the wire and not on the filesystem is not needed any more.

Simplify by removing support for the REFNAME_DOT_COMPONENT flag.

This means we'll be slightly stricter with invalid refs found in a
packed-refs file or during clone.  read_loose_refs() already checks
for and skips refnames with .components so it is not affected.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Reviewed-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-15 10:47:25 -07:00
Jonathan Nieder
62a2d52514 branch -d: avoid repeated symref resolution
If a repository gets in a broken state with too much symref nesting,
it cannot be repaired with "git branch -d":

 $ git symbolic-ref refs/heads/nonsense refs/heads/nonsense
 $ git branch -d nonsense
 error: branch 'nonsense' not found.

Worse, "git update-ref --no-deref -d" doesn't work for such repairs
either:

 $ git update-ref -d refs/heads/nonsense
 error: unable to resolve reference refs/heads/nonsense: Too many levels of symbolic links

Fix both by teaching resolve_ref_unsafe a new RESOLVE_REF_NO_RECURSE
flag and passing it when appropriate.

Callers can still read the value of a symref (for example to print a
message about it) with that flag set --- resolve_ref_unsafe will
resolve one level of symrefs and stop there.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Reviewed-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-15 10:47:25 -07:00
Ronnie Sahlberg
7695d118e5 refs.c: change resolve_ref_unsafe reading argument to be a flags field
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>
2014-10-15 10:47:24 -07:00
Ronnie Sahlberg
aae383db8c refs.c: make write_ref_sha1 static
No external users call write_ref_sha1 any more so let's declare it static.

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>
2014-10-15 10:47:23 -07:00
Ronnie Sahlberg
28e6a97e39 refs.c: ref_transaction_commit: distinguish name conflicts from other errors
In _commit, ENOTDIR can happen in the call to lock_ref_sha1_basic, either
when we lstat the new refname or if the name checking function reports that
the same type of conflict happened.  In both cases, it means that we can not
create the new ref due to a name conflict.

Start defining specific return codes for _commit.  TRANSACTION_NAME_CONFLICT
refers to a failure to create a ref due to a name conflict with another ref.
TRANSACTION_GENERIC_ERROR is for all other errors.

When "git fetch" is creating refs, name conflicts differ from other errors in
that they are likely to be resolved by running "git remote prune <remote>".
"git fetch" currently inspects errno to decide whether to give that advice.
Once it switches to the transaction API, it can check for
TRANSACTION_NAME_CONFLICT instead.

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>
2014-10-15 10:47:23 -07:00
Ronnie Sahlberg
5fe7d825da refs.c: pass a list of names to skip to is_refname_available
Change is_refname_available to take a list of strings to exclude when
checking for conflicts instead of just one single name. We can already
exclude a single name for the sake of renames. This generalizes that support.

ref_transaction_commit already tracks a set of refs that are being deleted
in an array.  This array is then used to exclude refs from being written to
the packed-refs file.  At some stage we will want to change this array to a
struct string_list and then we can pass it to is_refname_available via the
call to lock_ref_sha1_basic.  That will allow us to perform transactions
that perform multiple renames as long as there are no conflicts within the
starting or ending state.

For example, that would allow a single transaction that contains two
renames that are both individually conflicting:

   m -> n/n
   n -> m/m

No functional change intended yet.

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>
2014-10-15 10:47:23 -07:00
Ronnie Sahlberg
5d94a1b033 refs.c: call lock_ref_sha1_basic directly from commit
Skip using the lock_any_ref_for_update wrapper and call lock_ref_sha1_basic
directly from the commit function.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Reviewed-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-15 10:47:23 -07:00
Ronnie Sahlberg
8a9df90d9a refs.c: refuse to lock badly named refs in lock_ref_sha1_basic
Move the check for check_refname_format from lock_any_ref_for_update to
lock_ref_sha1_basic.  At some later stage we will get rid of
lock_any_ref_for_update completely.  This has no visible impact to callers
except for the inability to lock badly named refs, which is not possible
today already for other reasons.(*)

Keep lock_any_ref_for_update as a no-op wrapper.  It is the public facing
version of this interface and keeping it as a separate function will make
it easier to experiment with the internal lock_ref_sha1_basic signature.

(*) For example, if lock_ref_sha1_basic checks the refname format and
refuses to lock badly named refs, it will not be possible to delete
such refs because the first step of deletion is to lock the ref.  We
currently already fail in that case because these refs are not recognized
to exist:

 $ cp .git/refs/heads/master .git/refs/heads/echo...\*\*
 $ git branch -D .git/refs/heads/echo...\*\*
 error: branch '.git/refs/heads/echo...**' not found.

This has been broken for a while.  Later patches in the series will start
repairing the handling of badly named refs.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Reviewed-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-15 10:47:22 -07:00
Ronnie Sahlberg
7522e3dbcc rename_ref: don't ask read_ref_full where the ref came from
We call read_ref_full with a pointer to flags from rename_ref but since
we never actually use the returned flags we can just pass NULL here instead.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Reviewed-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-15 10:47:22 -07:00
Ronnie Sahlberg
db7516ab9f refs.c: pass the ref log message to _create/delete/update instead of _commit
Change the ref transaction API so that we pass the reflog message to the
create/delete/update functions instead of to ref_transaction_commit.
This allows different reflog messages for each ref update in a multi-ref
transaction.

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>
2014-10-15 10:47:22 -07:00
Ronnie Sahlberg
dbdcac7d5c refs.c: add an err argument to delete_ref_loose
Add an err argument to delete_ref_loose so that we can pass a descriptive
error string back to the caller. Pass the err argument from transaction
commit to this function so that transaction users will have a nice error
string if the transaction failed due to delete_ref_loose.

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>
2014-10-15 10:47:21 -07:00
Ronnie Sahlberg
3c93c847ca refs.c: lock_ref_sha1_basic is used for all refs
lock_ref_sha1_basic is used to lock refs that sit directly in the .git
dir such as HEAD and MERGE_HEAD in addition to the more ordinary refs
under "refs/".  Remove the note claiming otherwise.

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>
2014-10-15 10:47:21 -07:00
Ronnie Sahlberg
1054af7d04 wrapper.c: remove/unlink_or_warn: simplify, treat ENOENT as success
Simplify the function warn_if_unremovable slightly. Additionally, change
behaviour slightly. If we failed to remove the object because the object
does not exist, we can still return success back to the caller since none of
the callers depend on "fail if the file did not exist".

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>
2014-10-15 10:47:20 -07:00
Michael Haggerty
6e578a31e6 commit_packed_refs(): reimplement using fdopen_lock_file()
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-01 14:20:25 -07:00
Michael Haggerty
697cc8efd9 lockfile.h: extract new header file for the functions in lockfile.c
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>
2014-10-01 13:56:14 -07:00
Michael Haggerty
ec38b4e482 get_locked_file_path(): new function
Add a function to return the path of the file that is locked by a
lock_file object. This reduces the knowledge that callers have to have
about the lock_file layout.

Suggested-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-01 13:53:54 -07:00
Michael Haggerty
47ba4662bf lockfile: rename LOCK_NODEREF to LOCK_NO_DEREF
This makes it harder to misread the name as LOCK_NODE_REF.

Suggested-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-01 13:53:28 -07:00
Michael Haggerty
cf6950d3bf lockfile: change lock_file::filename into a strbuf
For now, we still make sure to allocate at least PATH_MAX characters
for the strbuf because resolve_symlink() doesn't know how to expand
the space for its return value.  (That will be fixed in a moment.)

Another alternative would be to just use a strbuf as scratch space in
lock_file() but then store a pointer to the naked string in struct
lock_file.  But lock_file objects are often reused.  By reusing the
same strbuf, we can avoid having to reallocate the string most times
when a lock_file object is reused.

Helped-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-01 13:50:01 -07:00
Michael Haggerty
91f1f19184 delete_ref_loose(): don't muck around in the lock_file's filename
It's bad manners. Especially since there could be a signal during the
call to unlink_or_warn(), in which case the signal handler will see
the wrong filename and delete the reference file, leaving the lockfile
behind.

So make our own copy to work with.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-01 13:45:11 -07:00
Michael Haggerty
7108ad232f cache.h: define constants LOCK_SUFFIX and LOCK_SUFFIX_LEN
There are a few places that use these values, so define constants for
them.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-01 13:45:11 -07:00
Michael Haggerty
e197c21807 unable_to_lock_die(): rename function from unable_to_lock_index_die()
This function is used for other things besides the index, so rename it
accordingly.

Suggested-by: Jeff King <peff@peff.net>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Reviewed-by: Ronnie Sahlberg <sahlberg@google.com>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-01 13:38:38 -07:00
Junio C Hamano
507fe835ed Merge branch 'da/rev-parse-verify-quiet'
"rev-parse --verify --quiet $name" is meant to quietly exit with a
non-zero status when $name is not a valid object name, but still
gave error messages in some cases.

* da/rev-parse-verify-quiet:
  stash: prefer --quiet over shell redirection of the standard error stream
  refs: make rev-parse --quiet actually quiet
  t1503: use test_must_be_empty
  Documentation: a note about stdout for git rev-parse --verify --quiet
2014-09-29 12:36:10 -07:00
Junio C Hamano
9bc4222746 Merge branch 'jk/faster-name-conflicts'
Optimize the check to see if a ref $F can be created by making sure
no existing ref has $F/ as its prefix, which especially matters in
a repository with a large number of existing refs.

* jk/faster-name-conflicts:
  refs: speed up is_refname_available
2014-09-26 14:39:43 -07:00