make copy_ref globally available

diff --git a/builtin/diff.c b/builtin/diff.c
index 89ae89cde1e6d8a0a2e02209f5396263a81bda5b..d4d80c982e99f9a16e4e5228a963d1f2f1836bfb 100644 (file)
--- a/builtin/diff.c
+++ b/builtin/diff.c
@@ -13,6 +13,7 @@
 #include "revision.h"
 #include "log-tree.h"
 #include "builtin.h"
+#include "submodule.h"
 
 struct blobinfo {
        unsigned char sha1[20];
@@ -21,7 +22,7 @@ struct blobinfo {
 };
 
 static const char builtin_diff_usage[] =
-"git diff <options> <rev>{0,2} -- <path>*";
+"git diff [<options>] [<commit> [<commit>]] [--] [<path>...]";
 
 static void stuff_change(struct diff_options *opt,
                         unsigned old_mode, unsigned new_mode,
@@ -196,12 +197,7 @@ static void refresh_index_quietly(void)
        discard_cache();
        read_cache();
        refresh_cache(REFRESH_QUIET|REFRESH_UNMERGED);
-
-       if (active_cache_changed &&
-           !write_cache(fd, active_cache, active_nr))
-               commit_locked_index(lock_file);
-
-       rollback_lock_file(lock_file);
+       update_index_if_able(&the_index, lock_file);
 }
 
 static int builtin_diff_files(struct rev_info *revs, int argc, const char **argv)
@@ -279,6 +275,7 @@ int cmd_diff(int argc, const char **argv, const char *prefix)
         */
 
        prefix = setup_git_directory_gently(&nongit);
+       gitmodules_config();
        git_config(git_diff_ui_config, NULL);
 
        if (diff_use_color_default == -1)
@@ -328,8 +325,11 @@ int cmd_diff(int argc, const char **argv, const char *prefix)
                        else if (!strcmp(arg, "--cached") ||
                                 !strcmp(arg, "--staged")) {
                                add_head_to_pending(&rev);
-                               if (!rev.pending.nr)
-                                       die("No HEAD commit to compare with (yet)");
+                               if (!rev.pending.nr) {
+                                       struct tree *tree;
+                                       tree = lookup_tree((const unsigned char*)EMPTY_TREE_SHA1_BIN);
+                                       add_pending_object(&rev, &tree->object, "HEAD");
+                               }
                                break;
                        }
                }