maps: use uniform lifecycle management functions

Currently, the lifecycle functions for maps (allocation, deallocation, resize)
are not named in a uniform way and do not have a uniform function signature.
Rename the functions to fix that, and stick to libgit2's naming scheme of saying
`git_foo_new`. This results in the following new interface for allocation:

- `int git_<t>map_new(git_<t>map **out)` to allocate a new map, returning an
  error code if we ran out of memory

- `void git_<t>map_free(git_<t>map *map)` to free a map

- `void git_<t>map_clear(git<t>map *map)` to remove all entries from a map

This commit also fixes all existing callers.

1 files changed, 2 insertions, 4 deletions

diff --git a/src/pack-objects.c b/src/pack-objects.c
index e1528646a..4ccc84d4b 100644
--- a/src/pack-objects.c
+++ b/src/pack-objects.c
@@ -141,12 +141,10 @@ int git_packbuilder_new(git_packbuilder **out, git_repository *repo)
 	pb = git__calloc(1, sizeof(*pb));
 	GIT_ERROR_CHECK_ALLOC(pb);
 
-	pb->object_ix = git_oidmap_alloc();
-	if (!pb->object_ix)
+	if (git_oidmap_new(&pb->object_ix) < 0)
 		goto on_error;
 
-	pb->walk_objects = git_oidmap_alloc();
-	if (!pb->walk_objects)
+	if (git_oidmap_new(&pb->walk_objects) < 0)
 		goto on_error;
 
 	git_pool_init(&pb->object_pool, sizeof(struct walk_object));