delta/git.git/refs.h, branch fc/mergetools-vimdiff3

Merge branch 'sb/refs-code-cleanup'

2013-11-01T14:38:58+00:00

* sb/refs-code-cleanup:
  cache: remove unused function 'have_git_dir'
  refs: remove unused function invalidate_ref_cache

refs: remove unused function invalidate_ref_cache

2013-10-28T15:55:56+00:00

The function 'invalidate_ref_cache' was introduced in 79c7ca5 (2011-10-17,
invalidate_ref_cache(): rename function from invalidate_cached_refs())
by a rename and elevated to be publicly usable in 8be8bde (2011-10-17,
invalidate_ref_cache(): expose this function in the refs API)

However it is not used anymore, as 8bf90dc (2011-10-17, write_ref_sha1():
only invalidate the loose ref cache) and (much) later 506a760 (2013-04-22,
refs: change how packed refs are deleted) removed any calls to this
function. So it seems as if we don't need that function any more,
good bye!

Signed-off-by: Stefan Beller 
Acked-by: Michael Haggerty 
Signed-off-by: Junio C Hamano

refs: add update_refs for multiple simultaneous updates

2013-09-04T18:10:28+00:00

Add 'struct ref_update' to encode the information needed to update or
delete a ref (name, new sha1, optional old sha1, no-deref flag).  Add
function 'update_refs' accepting an array of updates to perform.  First
sort the input array to order locks consistently everywhere and reject
multiple updates to the same ref.  Then acquire locks on all refs with
verified old values.  Then update or delete all refs accordingly.  Fail
if any one lock cannot be obtained or any one old value does not match.

Though the refs themselves cannot be modified together in a single
atomic transaction, this function does enable some useful semantics.
For example, a caller may create a new branch starting from the head of
another branch and rewind the original branch at the same time.  This
transfers ownership of commits between branches without risk of losing
commits added to the original branch by a concurrent process, or risk of
a concurrent process creating the new branch first.

Signed-off-by: Brad King 
Signed-off-by: Junio C Hamano

refs: report ref type from lock_any_ref_for_update

2013-08-30T21:57:28+00:00

Expose lock_ref_sha1_basic's type_p argument to callers of
lock_any_ref_for_update.  Update all call sites to ignore it by passing
NULL for now.

Signed-off-by: Brad King 
Signed-off-by: Junio C Hamano

refs: implement simple transactions for the packed-refs file

2013-06-20T22:50:17+00:00

Handle simple transactions for the packed-refs file at the
packed_ref_cache level via new functions lock_packed_refs(),
commit_packed_refs(), and rollback_packed_refs().

Only allow the packed ref cache to be modified (via add_packed_ref())
while the packed refs file is locked.

Change clone to add the new references within a transaction.

Signed-off-by: Michael Haggerty 
Signed-off-by: Junio C Hamano

Merge branch 'mh/reflife'

2013-06-14T15:46:14+00:00

Define memory ownership and lifetime rules for what for-each-ref
feeds to its callbacks (in short, "you do not own it, so make a
copy if you want to keep it").

* mh/reflife: (25 commits)
  refs: document the lifetime of the args passed to each_ref_fn
  register_ref(): make a copy of the bad reference SHA-1
  exclude_existing(): set existing_refs.strdup_strings
  string_list_add_refs_by_glob(): add a comment about memory management
  string_list_add_one_ref(): rename first parameter to "refname"
  show_head_ref(): rename first parameter to "refname"
  show_head_ref(): do not shadow name of argument
  add_existing(): do not retain a reference to sha1
  do_fetch(): clean up existing_refs before exiting
  do_fetch(): reduce scope of peer_item
  object_array_entry: fix memory handling of the name field
  find_first_merges(): remove unnecessary code
  find_first_merges(): initialize merges variable using initializer
  fsck: don't put a void*-shaped peg in a char*-shaped hole
  object_array_remove_duplicates(): rewrite to reduce copying
  revision: use object_array_filter() in implementation of gc_boundary()
  object_array: add function object_array_filter()
  revision: split some overly-long lines
  cmd_diff(): make it obvious which cases are exclusive of each other
  cmd_diff(): rename local variable "list" -> "entry"
  ...

refs: document the lifetime of the args passed to each_ref_fn

2013-06-02T22:28:47+00:00

The lifetime of the memory pointed to by the refname and sha1
arguments to each_ref_fn was never documented, but some callers used
to assume that it was essentially permanent.  In fact the API does
*not* guarantee that these objects live beyond a single callback
invocation.

In the current code, the lifetimes are bound together with the
lifetimes of the ref_caches.  Since these are usually long, the
callers usually got away with their sloppiness.  But even today, if a
ref_cache is invalidated the memory can be freed.  And planned changes
to reference caching, needed to eliminate race conditions, will
probably need to shorten the lifetimes of these objects.

The commits leading up to this have (hopefully) fixed all of the
callers of the for_each_ref()-like functions.  This commit does the
last step: documents what each_ref_fn callbacks can assume about
object lifetimes.

Signed-off-by: Michael Haggerty 
Signed-off-by: Junio C Hamano

Merge branch 'mh/packed-refs-various'

2013-05-29T21:23:49+00:00

Update reading and updating packed-refs file, correcting corner case
bugs.

* mh/packed-refs-various: (33 commits)
  refs: handle the main ref_cache specially
  refs: change do_for_each_*() functions to take ref_cache arguments
  pack_one_ref(): do some cheap tests before a more expensive one
  pack_one_ref(): use write_packed_entry() to do the writing
  pack_one_ref(): use function peel_entry()
  refs: inline function do_not_prune()
  pack_refs(): change to use do_for_each_entry()
  refs: use same lock_file object for both ref-packing functions
  pack_one_ref(): rename "path" parameter to "refname"
  pack-refs: merge code from pack-refs.{c,h} into refs.{c,h}
  pack-refs: rename handle_one_ref() to pack_one_ref()
  refs: extract a function write_packed_entry()
  repack_without_ref(): write peeled refs in the rewritten file
  t3211: demonstrate loss of peeled refs if a packed ref is deleted
  refs: change how packed refs are deleted
  search_ref_dir(): return an index rather than a pointer
  repack_without_ref(): silence errors for dangling packed refs
  t3210: test for spurious error messages for dangling packed refs
  refs: change the internal reference-iteration API
  refs: extract a function peel_entry()
  ...

pack-refs: merge code from pack-refs.{c,h} into refs.{c,h}

2013-05-01T22:33:11+00:00

pack-refs.c doesn't contain much code, and the code it does contain is
closely related to reference handling.  Moreover, there is some
duplication between pack_refs() and repack_without_ref().  Therefore,
merge pack-refs.c into refs.c and pack-refs.h into refs.h.

The code duplication will be addressed in future commits.

Signed-off-by: Michael Haggerty 
Signed-off-by: Junio C Hamano

peel_ref(): fix return value for non-peelable, not-current reference

2013-05-01T22:33:10+00:00

The old version was inconsistent: when a reference was
REF_KNOWS_PEELED but with a null peeled value, it returned non-zero
for the current reference but zero for other references.  Change the
behavior for non-current references to match that of current_ref,
which is what callers expect.  Document the behavior.

Current callers only call peel_ref() from within a for_each_ref-style
iteration and only for the current ref; therefore, the buggy code path
was never reached.

Signed-off-by: Michael Haggerty 
Signed-off-by: Junio C Hamano