find_unique_abbrev: move logic out of get_short_sha1()

The get_short_sha1() is only about reading short sha1s; we
do call it in a loop to check "is this long enough" for each
object, but otherwise it should not need to know about
things like our default_abbrev setting.

So instead of asking it to set default_automatic_abbrev as a
side-effect, let's just have find_unique_abbrev() pick the
right place to start its loop.  This requires a separate
approximate_object_count() function, but that naturally
belongs with the rest of sha1_file.c.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 6 insertions, 1 deletions

diff --git a/cache.h b/cache.h
index 0e2a059..f22ace5 100644
--- a/cache.h
+++ b/cache.h
@@ -1204,7 +1204,6 @@ struct object_context {
 #define GET_SHA1_TREEISH          020
 #define GET_SHA1_BLOB             040
 #define GET_SHA1_FOLLOW_SYMLINKS 0100
-#define GET_SHA1_AUTOMATIC	 0200
 #define GET_SHA1_ONLY_TO_DIE    04000
 
 #define GET_SHA1_DISAMBIGUATORS \
@@ -1456,6 +1455,12 @@ extern void prepare_packed_git(void);
 extern void reprepare_packed_git(void);
 extern void install_packed_git(struct packed_git *pack);
 
+/*
+ * Give a rough count of objects in the repository. This sacrifices accuracy
+ * for speed.
+ */
+unsigned long approximate_object_count(void);
+
 extern struct packed_git *find_sha1_pack(const unsigned char *sha1,
 					 struct packed_git *packs);