Merge branch 'nd/split-index'

An experiment to use two files (the base file and incremental
changes relative to it) to represent the index to reduce I/O cost
of rewriting a large index when only small part of the working tree
changes.

* nd/split-index: (32 commits)
  t1700: new tests for split-index mode
  t2104: make sure split index mode is off for the version test
  read-cache: force split index mode with GIT_TEST_SPLIT_INDEX
  read-tree: note about dropping split-index mode or index version
  read-tree: force split-index mode off on --index-output
  rev-parse: add --shared-index-path to get shared index path
  update-index --split-index: do not split if $GIT_DIR is read only
  update-index: new options to enable/disable split index mode
  split-index: strip pathname of on-disk replaced entries
  split-index: do not invalidate cache-tree at read time
  split-index: the reading part
  split-index: the writing part
  read-cache: mark updated entries for split index
  read-cache: save deleted entries in split index
  read-cache: mark new entries for split index
  read-cache: split-index mode
  read-cache: save index SHA-1 after reading
  entry.c: update cache_changed if refresh_cache is set in checkout_entry()
  cache-tree: mark istate->cache_changed on prime_cache_tree()
  cache-tree: mark istate->cache_changed on cache tree update
  ...

1 files changed, 3 insertions, 4 deletions

diff --git a/builtin/reset.c b/builtin/reset.c
index 850d53229..855d478e3 100644
--- a/builtin/reset.c
+++ b/builtin/reset.c
@@ -84,7 +84,7 @@ static int reset_index(const unsigned char *sha1, int reset_type, int quiet)
 
 	if (reset_type == MIXED || reset_type == HARD) {
 		tree = parse_tree_indirect(sha1);
-		prime_cache_tree(&active_cache_tree, tree);
+		prime_cache_tree(&the_index, tree);
 	}
 
 	return 0;
@@ -353,7 +353,7 @@ int cmd_reset(int argc, const char **argv, const char *prefix)
 
 	if (reset_type != SOFT) {
 		struct lock_file *lock = xcalloc(1, sizeof(*lock));
-		int newfd = hold_locked_index(lock, 1);
+		hold_locked_index(lock, 1);
 		if (reset_type == MIXED) {
 			int flags = quiet ? REFRESH_QUIET : REFRESH_IN_PORCELAIN;
 			if (read_from_tree(&pathspec, sha1, intent_to_add))
@@ -369,8 +369,7 @@ int cmd_reset(int argc, const char **argv, const char *prefix)
 				die(_("Could not reset index file to revision '%s'."), rev);
 		}
 
-		if (write_cache(newfd, active_cache, active_nr) ||
-		    commit_locked_index(lock))
+		if (write_locked_index(&the_index, lock, COMMIT_LOCK))
 			die(_("Could not write new index file."));
 	}