pack-objects: reuse on-disk deltas for thin "have" objects

diff --git a/pack-objects.c b/pack-objects.c
index 92708522e76b4565882177f899612d72a3f6d75a..9ae0cecd817640d7c4a82d0e5cdaa2eed71a2e2c 100644 (file)
--- a/pack-objects.c
+++ b/pack-objects.c
@@ -177,3 +177,22 @@ struct object_entry *packlist_alloc(struct packing_data *pdata,
 
        return new_entry;
 }
+
+void oe_set_delta_ext(struct packing_data *pdata,
+                     struct object_entry *delta,
+                     const unsigned char *sha1)
+{
+       struct object_entry *base;
+
+       ALLOC_GROW(pdata->ext_bases, pdata->nr_ext + 1, pdata->alloc_ext);
+       base = &pdata->ext_bases[pdata->nr_ext++];
+       memset(base, 0, sizeof(*base));
+       hashcpy(base->idx.oid.hash, sha1);
+
+       /* These flags mark that we are not part of the actual pack output. */
+       base->preferred_base = 1;
+       base->filled = 1;
+
+       delta->ext_base = 1;
+       delta->delta_idx = base - pdata->ext_bases + 1;
+}