packed_object_info: hoist delta type resolution to helper

To calculate the type of a packed object, we must walk down
its delta chain until we hit a true base object with a real
type. Most of the code in packed_object_info is for handling
this case.

Let's hoist it out into a separate helper function, which
will make it easier to make the type-lookup optional in the
future (and keep our indentation level sane).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/sha1_file.c b/sha1_file.c
index 285337819e3b9f8ca608a9e47e2e65fff8d725ce..8fb10e451cba0e07481c0c6f40ee97a7039c6360 100644 (file)
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -1710,52 +1710,21 @@ static int retry_bad_packed_offset(struct packed_git *p, off_t obj_offset)
        return type;
 }
 
-
 #define POI_STACK_PREALLOC 64
 
-static int packed_object_info(struct packed_git *p, off_t obj_offset,
-                             unsigned long *sizep, int *rtype,
-                             unsigned long *disk_sizep)
+static enum object_type packed_to_object_type(struct packed_git *p,
+                                             off_t obj_offset,
+                                             enum object_type type,
+                                             struct pack_window **w_curs,
+                                             off_t curpos)
 {
-       struct pack_window *w_curs = NULL;
-       unsigned long size;
-       off_t curpos = obj_offset;
-       enum object_type type;
        off_t small_poi_stack[POI_STACK_PREALLOC];
        off_t *poi_stack = small_poi_stack;
        int poi_stack_nr = 0, poi_stack_alloc = POI_STACK_PREALLOC;
 
-       type = unpack_object_header(p, &w_curs, &curpos, &size);
-
-       if (rtype)
-               *rtype = type; /* representation type */
-
-       if (sizep) {
-               if (type == OBJ_OFS_DELTA || type == OBJ_REF_DELTA) {
-                       off_t tmp_pos = curpos;
-                       off_t base_offset = get_delta_base(p, &w_curs, &tmp_pos,
-                                                          type, obj_offset);
-                       if (!base_offset) {
-                               type = OBJ_BAD;
-                               goto out;
-                       }
-                       *sizep = get_size_from_delta(p, &w_curs, tmp_pos);
-                       if (*sizep == 0) {
-                               type = OBJ_BAD;
-                               goto out;
-                       }
-               } else {
-                       *sizep = size;
-               }
-       }
-
-       if (disk_sizep) {
-               struct revindex_entry *revidx = find_pack_revindex(p, obj_offset);
-               *disk_sizep = revidx[1].offset - obj_offset;
-       }
-
        while (type == OBJ_OFS_DELTA || type == OBJ_REF_DELTA) {
                off_t base_offset;
+               unsigned long size;
                /* Push the object we're going to leave behind */
                if (poi_stack_nr >= poi_stack_alloc && poi_stack == small_poi_stack) {
                        poi_stack_alloc = alloc_nr(poi_stack_nr);
@@ -1766,11 +1735,11 @@ static int packed_object_info(struct packed_git *p, off_t obj_offset,
                }
                poi_stack[poi_stack_nr++] = obj_offset;
                /* If parsing the base offset fails, just unwind */
-               base_offset = get_delta_base(p, &w_curs, &curpos, type, obj_offset);
+               base_offset = get_delta_base(p, w_curs, &curpos, type, obj_offset);
                if (!base_offset)
                        goto unwind;
                curpos = obj_offset = base_offset;
-               type = unpack_object_header(p, &w_curs, &curpos, &size);
+               type = unpack_object_header(p, w_curs, &curpos, &size);
                if (type <= OBJ_NONE) {
                        /* If getting the base itself fails, we first
                         * retry the base, otherwise unwind */
@@ -1797,7 +1766,6 @@ static int packed_object_info(struct packed_git *p, off_t obj_offset,
 out:
        if (poi_stack != small_poi_stack)
                free(poi_stack);
-       unuse_pack(&w_curs);
        return type;
 
 unwind:
@@ -1811,6 +1779,51 @@ static int packed_object_info(struct packed_git *p, off_t obj_offset,
        goto out;
 }
 
+static int packed_object_info(struct packed_git *p, off_t obj_offset,
+                             unsigned long *sizep, int *rtype,
+                             unsigned long *disk_sizep)
+{
+       struct pack_window *w_curs = NULL;
+       unsigned long size;
+       off_t curpos = obj_offset;
+       enum object_type type;
+
+       type = unpack_object_header(p, &w_curs, &curpos, &size);
+
+       if (rtype)
+               *rtype = type; /* representation type */
+
+       if (sizep) {
+               if (type == OBJ_OFS_DELTA || type == OBJ_REF_DELTA) {
+                       off_t tmp_pos = curpos;
+                       off_t base_offset = get_delta_base(p, &w_curs, &tmp_pos,
+                                                          type, obj_offset);
+                       if (!base_offset) {
+                               type = OBJ_BAD;
+                               goto out;
+                       }
+                       *sizep = get_size_from_delta(p, &w_curs, tmp_pos);
+                       if (*sizep == 0) {
+                               type = OBJ_BAD;
+                               goto out;
+                       }
+               } else {
+                       *sizep = size;
+               }
+       }
+
+       if (disk_sizep) {
+               struct revindex_entry *revidx = find_pack_revindex(p, obj_offset);
+               *disk_sizep = revidx[1].offset - obj_offset;
+       }
+
+       type = packed_to_object_type(p, obj_offset, type, &w_curs, curpos);
+
+out:
+       unuse_pack(&w_curs);
+       return type;
+}
+
 static void *unpack_compressed_entry(struct packed_git *p,
                                    struct pack_window **w_curs,
                                    off_t curpos,