delta/git.git/object.h, branch jk/robustify-parse-commit

object_array_entry: fix memory handling of the name field

2013-06-02T22:28:46+00:00

Previously, the memory management of the object_array_entry::name
field was inconsistent and undocumented.  object_array_entries are
ultimately created by a single function, add_object_array_with_mode(),
which has an argument "const char *name".  This function used to
simply set the name field to reference the string pointed to by the
name parameter, and nobody on the object_array side ever freed the
memory.  Thus, it assumed that the memory for the name field would be
managed by the caller, and that the lifetime of that string would be
at least as long as the lifetime of the object_array_entry.  But
callers were inconsistent:

* Some passed pointers to constant strings or argv entries, which was
  OK.

* Some passed pointers to newly-allocated memory, but didn't arrange
  for the memory ever to be freed.

* Some passed the return value of sha1_to_hex(), which is a pointer to
  a statically-allocated buffer that can be overwritten at any time.

* Some passed pointers to refnames that they received from a
  for_each_ref()-type iteration, but the lifetimes of such refnames is
  not guaranteed by the refs API.

Bring consistency to this mess by changing object_array to make its
own copy for the object_array_entry::name field and free this memory
when an object_array_entry is deleted from the array.

Many callers were passing the empty string as the name parameter, so
as a performance optimization, treat the empty string specially.
Instead of making a copy, store a pointer to a statically-allocated
empty string to object_array_entry::name.  When deleting such an
entry, skip the free().

Change the callers that were already passing copies to
add_object_array_with_mode() to either skip the copy, or (if the
memory needed to be allocated anyway) freeing the memory itself.

A part of this commit effectively reverts

    70d26c6e76 read_revisions_from_stdin: make copies for handle_revision_arg

because the copying introduced by that commit (which is still
necessary) is now done at a deeper level.

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

object_array_remove_duplicates(): rewrite to reduce copying

2013-05-28T16:25:01+00:00

The old version copied one entry to its destination position, then
deleted any matching entries from the tail of the array.  This
required the tail of the array to be copied multiple times.  It didn't
affect the complexity of the algorithm because the whole tail has to
be searched through anyway.  But all the copying was unnecessary.

Instead, check for the existence of an entry with the same name in the
*head* of the list before copying an entry to its final position.
This way each entry has to be copied at most one time.

Extract a helper function contains_name() to do a bit of the work.

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

object_array: add function object_array_filter()

2013-05-28T16:25:01+00:00

Add a function that allows unwanted entries in an object_array to be
removed.  This encapsulation is a step towards giving object_array
ownership of its entries' name memory.

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

avoid segfaults on parse_object failure

2013-03-17T19:49:03+00:00

Many call-sites of parse_object assume that they will get a
non-NULL return value; this is not the case if we encounter
an error while parsing the object.

This patch adds a wrapper function around parse_object that
handles dying automatically, and uses it anywhere we
immediately try to access the return value as a non-NULL
pointer (i.e., anywhere that we would currently segfault).

This wrapper may also be useful in other places. The most
obvious one is code like:

  o = parse_object(sha1);
  if (!o)
	  die(...);

However, these should not be mechanically converted to
parse_object_or_die, as the die message is sometimes
customized. Later patches can address these sites on a
case-by-case basis.

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

Teach revision walking machinery to walk multiple times sequencially

2012-03-30T15:57:49+00:00

Previously it was not possible to iterate revisions twice using the
revision walking api. We add a reset_revision_walk() which clears the
used flags. This allows us to do multiple sequencial revision walks.

We add the appropriate calls to the existing submodule machinery doing
revision walks. This is done to avoid surprises if future code wants to
call these functions more than once during the processes lifetime.

Signed-off-by: Heiko Voigt 
Signed-off-by: Junio C Hamano

object.h: Remove obsolete struct object_refs

2011-03-14T17:49:28+00:00

7914053 (Remove unused object-ref code, 2008-02-25) removed all uses of
the structure from the code, but forgot to remove the type definition
itself.

Signed-off-by: Jakob Pfender 
Signed-off-by: Junio C Hamano

object.h: Add OBJECT_ARRAY_INIT macro and make use of it.

2010-08-30T05:42:49+00:00

Signed-off-by: Thiago Farina 
Signed-off-by: Junio C Hamano

object.c: remove unused functions

2010-01-18T06:49:36+00:00

object_list_append() and object_list_length}() are not used anywhere.

Signed-off-by: Junio C Hamano

Merge branch 'js/maint-all-implies-HEAD'

2009-01-26T01:13:02+00:00

* js/maint-all-implies-HEAD:
  bundle: allow the same ref to be given more than once
  revision walker: include a detached HEAD in --all

bundle: allow the same ref to be given more than once

2009-01-18T07:00:31+00:00

"git bundle create x master master" used to create a bundle that lists
the same branch (master) twice.  Cloning from such a bundle resulted in
a needless warning "warning: Duplicated ref: refs/remotes/origin/master".

Signed-off-by: Junio C Hamano