cat-file: provide %(deltabase) batch format

diff --git a/builtin/cat-file.c b/builtin/cat-file.c
index b2ca775a80f54fcceba344d5545fe3cb34ba0184..2e0af2e617e400a5c99465edd82f0dd1f8927680 100644 (file)
--- a/builtin/cat-file.c
+++ b/builtin/cat-file.c
@@ -118,6 +118,7 @@ struct expand_data {
        unsigned long size;
        unsigned long disk_size;
        const char *rest;
+       unsigned char delta_base_sha1[20];
 
        /*
         * If mark_query is true, we do not expand anything, but rather
@@ -174,6 +175,11 @@ static void expand_atom(struct strbuf *sb, const char *atom, int len,
                        data->split_on_whitespace = 1;
                else if (data->rest)
                        strbuf_addstr(sb, data->rest);
+       } else if (is_atom("deltabase", atom, len)) {
+               if (data->mark_query)
+                       data->info.delta_base_sha1 = data->delta_base_sha1;
+               else
+                       strbuf_addstr(sb, sha1_to_hex(data->delta_base_sha1));
        } else
                die("unknown format element: %.*s", len, atom);
 }