Merge branch 'ma/skip-writing-unchanged-index'

Internal API clean-up to allow write_locked_index() optionally skip
writing the in-core index when it is not modified.

* ma/skip-writing-unchanged-index:
write_locked_index(): add flag to avoid writing unchanged index

diff --git a/builtin/add.c b/builtin/add.c
index ac7c1c327766c6a729ab0377fd71c2f8e9042d00..9ef7fb02d56aac94d104b50aed7d7dfda09cfc98 100644 (file)
--- a/builtin/add.c
+++ b/builtin/add.c
@@ -534,10 +534,9 @@ int cmd_add(int argc, const char **argv, const char *prefix)
        unplug_bulk_checkin();
 
 finish:
-       if (active_cache_changed) {
-               if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
-                       die(_("Unable to write new index file"));
-       }
+       if (write_locked_index(&the_index, &lock_file,
+                              COMMIT_LOCK | SKIP_IF_UNCHANGED))
+               die(_("Unable to write new index file"));
 
        UNLEAK(pathspec);
        UNLEAK(dir);

diff --git a/builtin/commit.c b/builtin/commit.c
index 092077c3eef7a81b3d814cee951cee98e37eac02..37fcb55ab0a03a5fdabaca1913bc700201fd8e10 100644 (file)
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -389,13 +389,9 @@ static const char *prepare_index(int argc, const char **argv, const char *prefix
                if (active_cache_changed
                    || !cache_tree_fully_valid(active_cache_tree))
                        update_main_cache_tree(WRITE_TREE_SILENT);
-               if (active_cache_changed) {
-                       if (write_locked_index(&the_index, &index_lock,
-                                              COMMIT_LOCK))
-                               die(_("unable to write new_index file"));
-               } else {
-                       rollback_lock_file(&index_lock);
-               }
+               if (write_locked_index(&the_index, &index_lock,
+                                      COMMIT_LOCK | SKIP_IF_UNCHANGED))
+                       die(_("unable to write new_index file"));
                commit_style = COMMIT_AS_IS;
                ret = get_index_file();
                goto out;

diff --git a/builtin/merge.c b/builtin/merge.c
index e8d9d4383ed69bd5783b0092a2ee221fc29ce439..ee050a47f34d7394d048f955baabb37a9e716ef8 100644 (file)
--- a/builtin/merge.c
+++ b/builtin/merge.c
@@ -652,10 +652,9 @@ static int try_merge_strategy(const char *strategy, struct commit_list *common,
 
        hold_locked_index(&lock, LOCK_DIE_ON_ERROR);
        refresh_cache(REFRESH_QUIET);
-       if (active_cache_changed &&
-           write_locked_index(&the_index, &lock, COMMIT_LOCK))
+       if (write_locked_index(&the_index, &lock,
+                              COMMIT_LOCK | SKIP_IF_UNCHANGED))
                return error(_("Unable to write index."));
-       rollback_lock_file(&lock);
 
        if (!strcmp(strategy, "recursive") || !strcmp(strategy, "subtree")) {
                int clean, x;
@@ -692,10 +691,9 @@ static int try_merge_strategy(const char *strategy, struct commit_list *common,
                                remoteheads->item, reversed, &result);
                if (clean < 0)
                        exit(128);
-               if (active_cache_changed &&
-                   write_locked_index(&the_index, &lock, COMMIT_LOCK))
+               if (write_locked_index(&the_index, &lock,
+                                      COMMIT_LOCK | SKIP_IF_UNCHANGED))
                        die (_("unable to write %s"), get_index_file());
-               rollback_lock_file(&lock);
                return clean ? 0 : 1;
        } else {
                return try_merge_command(strategy, xopts_nr, xopts,
@@ -811,10 +809,9 @@ static int merge_trivial(struct commit *head, struct commit_list *remoteheads)
 
        hold_locked_index(&lock, LOCK_DIE_ON_ERROR);
        refresh_cache(REFRESH_QUIET);
-       if (active_cache_changed &&
-           write_locked_index(&the_index, &lock, COMMIT_LOCK))
+       if (write_locked_index(&the_index, &lock,
+                              COMMIT_LOCK | SKIP_IF_UNCHANGED))
                return error(_("Unable to write index."));
-       rollback_lock_file(&lock);
 
        write_tree_trivial(&result_tree);
        printf(_("Wonderful.\n"));

diff --git a/builtin/mv.c b/builtin/mv.c
index 8eceb310aae5f8007475f571a0146832eab0be49..6d141f7a532c08e52f1f5f82330d046c60073f93 100644 (file)
--- a/builtin/mv.c
+++ b/builtin/mv.c
@@ -293,8 +293,8 @@ int cmd_mv(int argc, const char **argv, const char *prefix)
        if (gitmodules_modified)
                stage_updated_gitmodules(&the_index);
 
-       if (active_cache_changed &&
-           write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
+       if (write_locked_index(&the_index, &lock_file,
+                              COMMIT_LOCK | SKIP_IF_UNCHANGED))
                die(_("Unable to write new index file"));
 
        return 0;

diff --git a/builtin/rm.c b/builtin/rm.c
index a818efe230a0667b9e3e5f03efbb11b1db1df273..4447bb4d0faf8c34f3fc96361a651eaad396d6d4 100644 (file)
--- a/builtin/rm.c
+++ b/builtin/rm.c
@@ -385,10 +385,9 @@ int cmd_rm(int argc, const char **argv, const char *prefix)
                        stage_updated_gitmodules(&the_index);
        }
 
-       if (active_cache_changed) {
-               if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
-                       die(_("Unable to write new index file"));
-       }
+       if (write_locked_index(&the_index, &lock_file,
+                              COMMIT_LOCK | SKIP_IF_UNCHANGED))
+               die(_("Unable to write new index file"));
 
        return 0;
 }

diff --git a/cache.h b/cache.h
index d06932ed0bd049c8d41906da3508725c8978aa1c..a61b2d3f0d79b0f56992e0343803811f5265d716 100644 (file)
--- a/cache.h
+++ b/cache.h
@@ -599,6 +599,7 @@ extern int read_index_unmerged(struct index_state *);
 
 /* For use with `write_locked_index()`. */
 #define COMMIT_LOCK            (1 << 0)
+#define SKIP_IF_UNCHANGED      (1 << 1)
 
 /*
  * Write the index while holding an already-taken lock. Close the lock,
@@ -615,6 +616,9 @@ extern int read_index_unmerged(struct index_state *);
  * With `COMMIT_LOCK`, the lock is always committed or rolled back.
  * Without it, the lock is closed, but neither committed nor rolled
  * back.
+ *
+ * If `SKIP_IF_UNCHANGED` is given and the index is unchanged, nothing
+ * is written (and the lock is rolled back if `COMMIT_LOCK` is given).
  */
 extern int write_locked_index(struct index_state *, struct lock_file *lock, unsigned flags);
 

diff --git a/merge-recursive.c b/merge-recursive.c
index 129577987ba25402a6b9494b103a4643e2b37e68..2f232ad3b40e6a94ea78bd856a4ea2deaaf1d468 100644 (file)
--- a/merge-recursive.c
+++ b/merge-recursive.c
@@ -2223,10 +2223,9 @@ int merge_recursive_generic(struct merge_options *o,
                return clean;
        }
 
-       if (active_cache_changed &&
-           write_locked_index(&the_index, &lock, COMMIT_LOCK))
+       if (write_locked_index(&the_index, &lock,
+                              COMMIT_LOCK | SKIP_IF_UNCHANGED))
                return err(o, _("Unable to write index."));
-       rollback_lock_file(&lock);
 
        return clean ? 0 : 1;
 }

diff --git a/read-cache.c b/read-cache.c
index 977921d90c65ea94b40cb7f8332246bf77c0f215..d05eb725b533d3b70daca910df60d27de9ce947c 100644 (file)
--- a/read-cache.c
+++ b/read-cache.c
@@ -2538,6 +2538,12 @@ int write_locked_index(struct index_state *istate, struct lock_file *lock,
        int new_shared_index, ret;
        struct split_index *si = istate->split_index;
 
+       if ((flags & SKIP_IF_UNCHANGED) && !istate->cache_changed) {
+               if (flags & COMMIT_LOCK)
+                       rollback_lock_file(lock);
+               return 0;
+       }
+
        if (istate->fsmonitor_last_update)
                fill_fsmonitor_bitmap(istate);
 

diff --git a/rerere.c b/rerere.c
index 79203c6c1eae0db5515030b138e9e40e219af5f5..ea24d4c2f47ab6495d97f38245dd420a1ad38391 100644 (file)
--- a/rerere.c
+++ b/rerere.c
@@ -719,11 +719,9 @@ static void update_paths(struct string_list *update)
                        item->string);
        }
 
-       if (active_cache_changed) {
-               if (write_locked_index(&the_index, &index_lock, COMMIT_LOCK))
-                       die("Unable to write new index file");
-       } else
-               rollback_lock_file(&index_lock);
+       if (write_locked_index(&the_index, &index_lock,
+                              COMMIT_LOCK | SKIP_IF_UNCHANGED))
+               die("Unable to write new index file");
 }
 
 static void remove_variant(struct rerere_id *id)

diff --git a/sequencer.c b/sequencer.c
index 091bd6bda5c55c27e2d0688a5e12988e22e6e431..f9d1001dee9ad10e243aaeafc46fbdd13597fce7 100644 (file)
--- a/sequencer.c
+++ b/sequencer.c
@@ -517,15 +517,14 @@ static int do_recursive_merge(struct commit *base, struct commit *next,
                return clean;
        }
 
-       if (active_cache_changed &&
-           write_locked_index(&the_index, &index_lock, COMMIT_LOCK))
+       if (write_locked_index(&the_index, &index_lock,
+                              COMMIT_LOCK | SKIP_IF_UNCHANGED))
                /*
                 * TRANSLATORS: %s will be "revert", "cherry-pick" or
                 * "rebase -i".
                 */
                return error(_("%s: Unable to write new index file"),
                        _(action_name(opts)));
-       rollback_lock_file(&index_lock);
 
        if (!clean)
                append_conflicts_hint(msgbuf);
@@ -1713,13 +1712,13 @@ static int read_and_refresh_cache(struct replay_opts *opts)
                        _(action_name(opts)));
        }
        refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED, NULL, NULL, NULL);
-       if (the_index.cache_changed && index_fd >= 0) {
-               if (write_locked_index(&the_index, &index_lock, COMMIT_LOCK)) {
+       if (index_fd >= 0) {
+               if (write_locked_index(&the_index, &index_lock,
+                                      COMMIT_LOCK | SKIP_IF_UNCHANGED)) {
                        return error(_("git %s: failed to refresh the index"),
                                _(action_name(opts)));
                }
        }
-       rollback_lock_file(&index_lock);
        return 0;
 }