[PATCH 3/4] index-pack: Track the object_entry that creates each base_data

["Shawn O. Pearce" <spearce@spearce.org>]

If we free the data stored within a base_data we need the struct
object_entry to get the data back again for use with another
dependent delta.  Storing the object_entry* makes it simple to call
get_data_from_pack() to recover the compressed information.

This however means we must add the missing baes object to the end
of our packfile prior to calling resolve_delta() on each of the
dependent deltas.  Adding the base first ensures we can read the
base back from the pack we indexing, as if it had been included by
the remote side.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
---
 index-pack.c |   18 ++++++++++++------
 1 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/index-pack.c b/index-pack.c
index 6c59fd3..7239e89 100644
--- a/index-pack.c
+++ b/index-pack.c
@@ -29,6 +29,7 @@ union delta_base {
 struct base_data {
 	struct base_data *base;
 	struct base_data *child;
+	struct object_entry *obj;
 	void *data;
 	unsigned long size;
 };
@@ -476,6 +477,7 @@ static void resolve_delta(struct object_entry *delta_obj,
 	sha1_object(result.data, result.size, type, delta_obj->idx.sha1);
 	nr_resolved_deltas++;
 
+	result.obj = delta_obj;
 	link_base_data(base_obj, &result);
 
 	hashcpy(delta_base.sha1, delta_obj->idx.sha1);
@@ -588,6 +590,7 @@ static void parse_pack_objects(unsigned char *sha1)
 			continue;
 		base_obj.data = get_data_from_pack(obj);
 		base_obj.size = obj->size;
+		base_obj.obj = obj;
 		link_base_data(NULL, &base_obj);
 
 		if (ref)
@@ -633,7 +636,8 @@ static int write_compressed(int fd, void *in, unsigned int size, uint32_t *obj_c
 	return size;
 }
 
-static void append_obj_to_pack(const unsigned char *sha1, void *buf,
+static struct object_entry *append_obj_to_pack(
+			       const unsigned char *sha1, void *buf,
 			       unsigned long size, enum object_type type)
 {
 	struct object_entry *obj = &objects[nr_objects++];
@@ -654,6 +658,7 @@ static void append_obj_to_pack(const unsigned char *sha1, void *buf,
 	obj[1].idx.offset = obj[0].idx.offset + n;
 	obj[1].idx.offset += write_compressed(output_fd, buf, size, &obj[0].idx.crc32);
 	hashcpy(obj->idx.sha1, sha1);
+	return obj;
 }
 
 static int delta_pos_compare(const void *_a, const void *_b)
@@ -697,6 +702,12 @@ static void fix_unresolved_deltas(int nr_unresolved)
 		base_obj.data = read_sha1_file(d->base.sha1, &type, &base_obj.size);
 		if (!base_obj.data)
 			continue;
+
+		if (check_sha1_signature(d->base.sha1, base_obj.data,
+				base_obj.size, typename(type)))
+			die("local object %s is corrupt", sha1_to_hex(d->base.sha1));
+		base_obj.obj = append_obj_to_pack(d->base.sha1, base_obj.data,
+			base_obj.size, type);
 		link_base_data(NULL, &base_obj);
 
 		find_delta_children(&d->base, &first, &last);
@@ -706,11 +717,6 @@ static void fix_unresolved_deltas(int nr_unresolved)
 				resolve_delta(child, &base_obj, type);
 		}
 
-		if (check_sha1_signature(d->base.sha1, base_obj.data,
-				base_obj.size, typename(type)))
-			die("local object %s is corrupt", sha1_to_hex(d->base.sha1));
-		append_obj_to_pack(d->base.sha1, base_obj.data,
-			base_obj.size, type);
 		unlink_base_data(&base_obj);
 		display_progress(progress, nr_resolved_deltas);
 	}
-- 
1.5.6.2.393.g45096