#include "tree.h"
 #include "progress.h"
 #include "fsck.h"
-#include "exec_cmd.h"
+#include "exec-cmd.h"
 #include "streaming.h"
 #include "thread-utils.h"
 #include "packfile.h"
+#include "object-store.h"
 
 static const char index_pack_usage[] =
 "git index-pack [-v] [-o <index-file>] [--keep | --keep=<msg>] [--verify] [--strict] (<pack-file> | --stdin [--fix-thin] [<pack-file>])";
        int pack_fd;
 };
 
+/* Remember to update object flag allocation in object.h */
 #define FLAG_LINK (1u<<20)
 #define FLAG_CHECKED (1u<<21)
 
 
        if (!(obj->flags & FLAG_CHECKED)) {
                unsigned long size;
-               int type = sha1_object_info(obj->oid.hash, &size);
+               int type = oid_object_info(&obj->oid, &size);
                if (type <= 0)
                        die(_("did not receive expected object %s"),
                              oid_to_hex(&obj->oid));
 
        memset(&data, 0, sizeof(data));
        data.entry = entry;
-       data.st = open_istream(entry->idx.oid.hash, &type, &size, NULL);
+       data.st = open_istream(&entry->idx.oid, &type, &size, NULL);
        if (!data.st)
                return -1;
        if (size != entry->size || type != entry->type)
                enum object_type has_type;
                unsigned long has_size;
                read_lock();
-               has_type = sha1_object_info(oid->hash, &has_size);
+               has_type = oid_object_info(oid, &has_size);
                if (has_type < 0)
                        die(_("cannot read existing object info %s"), oid_to_hex(oid));
                if (has_type != type || has_size != size)
                        die(_("SHA1 COLLISION FOUND WITH %s !"), oid_to_hex(oid));
-               has_data = read_sha1_file(oid->hash, &has_type, &has_size);
+               has_data = read_object_file(oid, &has_type, &has_size);
                read_unlock();
                if (!data)
                        data = new_data = get_data_from_pack(obj_entry);
                free(has_data);
        }
 
-       if (strict) {
+       if (strict || do_fsck_object) {
                read_lock();
                if (type == OBJ_BLOB) {
                        struct blob *blob = lookup_blob(oid);
                        if (do_fsck_object &&
                            fsck_object(obj, buf, size, &fsck_options))
                                die(_("Error in object"));
-                       if (fsck_walk(obj, NULL, &fsck_options))
+                       if (strict && fsck_walk(obj, NULL, &fsck_options))
                                die(_("Not all child objects of %s are reachable"), oid_to_hex(&obj->oid));
 
                        if (obj->type == OBJ_TREE) {
 
                if (objects[d->obj_no].real_type != OBJ_REF_DELTA)
                        continue;
-               base_obj->data = read_sha1_file(d->oid.hash, &type, &base_obj->size);
+               base_obj->data = read_object_file(&d->oid, &type,
+                                                 &base_obj->size);
                if (!base_obj->data)
                        continue;
 
-               if (check_sha1_signature(d->oid.hash, base_obj->data,
+               if (check_object_signature(&d->oid, base_obj->data,
                                base_obj->size, type_name(type)))
                        die(_("local object %s is corrupt"), oid_to_hex(&d->oid));
                base_obj->obj = append_obj_to_pack(f, d->oid.hash,
        /*
         * Get rid of the idx file as we do not need it anymore.
         * NEEDSWORK: extract this bit from free_pack_by_name() in
-        * sha1_file.c, perhaps?  It shouldn't matter very much as we
+        * sha1-file.c, perhaps?  It shouldn't matter very much as we
         * know we haven't installed this pack (hence we never have
         * read anything from it).
         */
                        } else if (!strcmp(arg, "--check-self-contained-and-connected")) {
                                strict = 1;
                                check_self_contained_and_connected = 1;
+                       } else if (!strcmp(arg, "--fsck-objects")) {
+                               do_fsck_object = 1;
                        } else if (!strcmp(arg, "--verify")) {
                                verify = 1;
                        } else if (!strcmp(arg, "--verify-stat")) {