pack: move pack name-related functions

Currently, sha1_file.c and cache.h contain many functions, both related
to and unrelated to packfiles. This makes both files very large and
causes an unclear separation of concerns.

Create a new file, packfile.c, to hold all packfile-related functions
currently in sha1_file.c. It has a corresponding header packfile.h.

In this commit, the pack name-related functions are moved. Subsequent
commits will move the other functions.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 23 insertions, 0 deletions

diff --git a/packfile.c b/packfile.c
new file mode 100644
index 0000000000..0d191dfd60
--- /dev/null
+++ b/packfile.c
@@ -0,0 +1,23 @@
+#include "cache.h"
+
+char *odb_pack_name(struct strbuf *buf,
+		    const unsigned char *sha1,
+		    const char *ext)
+{
+	strbuf_reset(buf);
+	strbuf_addf(buf, "%s/pack/pack-%s.%s", get_object_directory(),
+		    sha1_to_hex(sha1), ext);
+	return buf->buf;
+}
+
+char *sha1_pack_name(const unsigned char *sha1)
+{
+	static struct strbuf buf = STRBUF_INIT;
+	return odb_pack_name(&buf, sha1, "pack");
+}
+
+char *sha1_pack_index_name(const unsigned char *sha1)
+{
+	static struct strbuf buf = STRBUF_INIT;
+	return odb_pack_name(&buf, sha1, "idx");
+}