sha1_file: add repository argument to alt_odb_usable

Add a repository argument to allow the alt_odb_usable caller to be
more specific about which repository to act on. This is a small
mechanical change; it doesn't change the implementation to handle
repositories other than the_repository yet.

Since the implementation does not yet work with other repositories,
use a wrapper macro to enforce that the caller passes in
the_repository as the first argument. It would be more appealing to
use BUILD_ASSERT_OR_ZERO to enforce this, but that doesn't work
because it requires a compile-time constant and common compilers like
gcc 4.8.4 do not consider "r == the_repository" a compile-time
constant.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/sha1_file.c b/sha1_file.c
index 7c6ffd205a..1c757b44a3 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -280,7 +280,9 @@ static const char *alt_sha1_path(struct alternate_object_database *alt,
 /*
  * Return non-zero iff the path is usable as an alternate object database.
  */
-static int alt_odb_usable(struct strbuf *path, const char *normalized_objdir)
+#define alt_odb_usable(r, p, n) alt_odb_usable_##r(p, n)
+static int alt_odb_usable_the_repository(struct strbuf *path,
+					 const char *normalized_objdir)
 {
 	struct alternate_object_database *alt;
 
@@ -348,7 +350,7 @@ static int link_alt_odb_entry(const char *entry, const char *relative_base,
 	while (pathbuf.len && pathbuf.buf[pathbuf.len - 1] == '/')
 		strbuf_setlen(&pathbuf, pathbuf.len - 1);
 
-	if (!alt_odb_usable(&pathbuf, normalized_objdir)) {
+	if (!alt_odb_usable(the_repository, &pathbuf, normalized_objdir)) {
 		strbuf_release(&pathbuf);
 		return -1;
 	}