1 files changed, 232 insertions, 23 deletions

diff --git a/builtin/update-index.c b/builtin/update-index.c
index 6271b54ad..1c94ca59b 100644
--- a/builtin/update-index.c
+++ b/builtin/update-index.c
@@ -33,6 +33,16 @@ static int mark_valid_only;
 static int mark_skip_worktree_only;
 #define MARK_FLAG 1
 #define UNMARK_FLAG 2
+static struct strbuf mtime_dir = STRBUF_INIT;
+
+/* Untracked cache mode */
+enum uc_mode {
+	UC_UNSPECIFIED = -1,
+	UC_DISABLE = 0,
+	UC_ENABLE,
+	UC_TEST,
+	UC_FORCE
+};
 
 __attribute__((format (printf, 1, 2)))
 static void report(const char *fmt, ...)
@@ -48,6 +58,166 @@ static void report(const char *fmt, ...)
 	va_end(vp);
 }
 
+static void remove_test_directory(void)
+{
+	if (mtime_dir.len)
+		remove_dir_recursively(&mtime_dir, 0);
+}
+
+static const char *get_mtime_path(const char *path)
+{
+	static struct strbuf sb = STRBUF_INIT;
+	strbuf_reset(&sb);
+	strbuf_addf(&sb, "%s/%s", mtime_dir.buf, path);
+	return sb.buf;
+}
+
+static void xmkdir(const char *path)
+{
+	path = get_mtime_path(path);
+	if (mkdir(path, 0700))
+		die_errno(_("failed to create directory %s"), path);
+}
+
+static int xstat_mtime_dir(struct stat *st)
+{
+	if (stat(mtime_dir.buf, st))
+		die_errno(_("failed to stat %s"), mtime_dir.buf);
+	return 0;
+}
+
+static int create_file(const char *path)
+{
+	int fd;
+	path = get_mtime_path(path);
+	fd = open(path, O_CREAT | O_RDWR, 0644);
+	if (fd < 0)
+		die_errno(_("failed to create file %s"), path);
+	return fd;
+}
+
+static void xunlink(const char *path)
+{
+	path = get_mtime_path(path);
+	if (unlink(path))
+		die_errno(_("failed to delete file %s"), path);
+}
+
+static void xrmdir(const char *path)
+{
+	path = get_mtime_path(path);
+	if (rmdir(path))
+		die_errno(_("failed to delete directory %s"), path);
+}
+
+static void avoid_racy(void)
+{
+	/*
+	 * not use if we could usleep(10) if USE_NSEC is defined. The
+	 * field nsec could be there, but the OS could choose to
+	 * ignore it?
+	 */
+	sleep(1);
+}
+
+static int test_if_untracked_cache_is_supported(void)
+{
+	struct stat st;
+	struct stat_data base;
+	int fd, ret = 0;
+
+	strbuf_addstr(&mtime_dir, "mtime-test-XXXXXX");
+	if (!mkdtemp(mtime_dir.buf))
+		die_errno("Could not make temporary directory");
+
+	fprintf(stderr, _("Testing mtime in '%s' "), xgetcwd());
+	atexit(remove_test_directory);
+	xstat_mtime_dir(&st);
+	fill_stat_data(&base, &st);
+	fputc('.', stderr);
+
+	avoid_racy();
+	fd = create_file("newfile");
+	xstat_mtime_dir(&st);
+	if (!match_stat_data(&base, &st)) {
+		close(fd);
+		fputc('\n', stderr);
+		fprintf_ln(stderr,_("directory stat info does not "
+				    "change after adding a new file"));
+		goto done;
+	}
+	fill_stat_data(&base, &st);
+	fputc('.', stderr);
+
+	avoid_racy();
+	xmkdir("new-dir");
+	xstat_mtime_dir(&st);
+	if (!match_stat_data(&base, &st)) {
+		close(fd);
+		fputc('\n', stderr);
+		fprintf_ln(stderr, _("directory stat info does not change "
+				     "after adding a new directory"));
+		goto done;
+	}
+	fill_stat_data(&base, &st);
+	fputc('.', stderr);
+
+	avoid_racy();
+	write_or_die(fd, "data", 4);
+	close(fd);
+	xstat_mtime_dir(&st);
+	if (match_stat_data(&base, &st)) {
+		fputc('\n', stderr);
+		fprintf_ln(stderr, _("directory stat info changes "
+				     "after updating a file"));
+		goto done;
+	}
+	fputc('.', stderr);
+
+	avoid_racy();
+	close(create_file("new-dir/new"));
+	xstat_mtime_dir(&st);
+	if (match_stat_data(&base, &st)) {
+		fputc('\n', stderr);
+		fprintf_ln(stderr, _("directory stat info changes after "
+				     "adding a file inside subdirectory"));
+		goto done;
+	}
+	fputc('.', stderr);
+
+	avoid_racy();
+	xunlink("newfile");
+	xstat_mtime_dir(&st);
+	if (!match_stat_data(&base, &st)) {
+		fputc('\n', stderr);
+		fprintf_ln(stderr, _("directory stat info does not "
+				     "change after deleting a file"));
+		goto done;
+	}
+	fill_stat_data(&base, &st);
+	fputc('.', stderr);
+
+	avoid_racy();
+	xunlink("new-dir/new");
+	xrmdir("new-dir");
+	xstat_mtime_dir(&st);
+	if (!match_stat_data(&base, &st)) {
+		fputc('\n', stderr);
+		fprintf_ln(stderr, _("directory stat info does not "
+				     "change after deleting a directory"));
+		goto done;
+	}
+
+	if (rmdir(mtime_dir.buf))
+		die_errno(_("failed to delete directory %s"), mtime_dir.buf);
+	fprintf_ln(stderr, _(" OK"));
+	ret = 1;
+
+done:
+	strbuf_release(&mtime_dir);
+	return ret;
+}
+
 static int mark_ce_flags(const char *path, int flag, int mark)
 {
 	int namelen = strlen(path);
@@ -307,12 +477,14 @@ static void update_one(const char *path)
 	report("add '%s'", path);
 }
 
-static void read_index_info(int line_termination)
+static void read_index_info(int nul_term_line)
 {
 	struct strbuf buf = STRBUF_INIT;
 	struct strbuf uq = STRBUF_INIT;
+	strbuf_getline_fn getline_fn;
 
-	while (strbuf_getline(&buf, stdin, line_termination) != EOF) {
+	getline_fn = nul_term_line ? strbuf_getline_nul : strbuf_getline_lf;
+	while (getline_fn(&buf, stdin) != EOF) {
 		char *ptr, *tab;
 		char *path_name;
 		unsigned char sha1[20];
@@ -361,7 +533,7 @@ static void read_index_info(int line_termination)
 			goto bad_line;
 
 		path_name = ptr;
-		if (line_termination && path_name[0] == '"') {
+		if (!nul_term_line && path_name[0] == '"') {
 			strbuf_reset(&uq);
 			if (unquote_c_style(&uq, path_name, NULL)) {
 				die("git update-index: bad quoting of path name");
@@ -532,10 +704,9 @@ static int do_unresolve(int ac, const char **av,
 
 	for (i = 1; i < ac; i++) {
 		const char *arg = av[i];
-		const char *p = prefix_path(prefix, prefix_length, arg);
+		char *p = prefix_path(prefix, prefix_length, arg);
 		err |= unresolve_one(p);
-		if (p < arg || p > arg + strlen(arg))
-			free((char *)p);
+		free(p);
 	}
 	return err;
 }
@@ -684,12 +855,12 @@ static int cacheinfo_callback(struct parse_opt_ctx_t *ctx,
 static int stdin_cacheinfo_callback(struct parse_opt_ctx_t *ctx,
 			      const struct option *opt, int unset)
 {
-	int *line_termination = opt->value;
+	int *nul_term_line = opt->value;
 
 	if (ctx->argc != 1)
 		return error("option '%s' must be the last argument", opt->long_name);
 	allow_add = allow_replace = allow_remove = 1;
-	read_index_info(*line_termination);
+	read_index_info(*nul_term_line);
 	return 0;
 }
 
@@ -741,7 +912,8 @@ static int reupdate_callback(struct parse_opt_ctx_t *ctx,
 
 int cmd_update_index(int argc, const char **argv, const char *prefix)
 {
-	int newfd, entries, has_errors = 0, line_termination = '\n';
+	int newfd, entries, has_errors = 0, nul_term_line = 0;
+	enum uc_mode untracked_cache = UC_UNSPECIFIED;
 	int read_from_stdin = 0;
 	int prefix_length = prefix ? strlen(prefix) : 0;
 	int preferred_index_format = 0;
@@ -751,6 +923,7 @@ int cmd_update_index(int argc, const char **argv, const char *prefix)
 	int split_index = -1;
 	struct lock_file *lock_file;
 	struct parse_opt_ctx_t ctx;
+	strbuf_getline_fn getline_fn;
 	int parseopt_state = PARSE_OPT_UNKNOWN;
 	struct option options[] = {
 		OPT_BIT('q', NULL, &refresh_args.flags,
@@ -802,13 +975,13 @@ int cmd_update_index(int argc, const char **argv, const char *prefix)
 			N_("add to index only; do not add content to object database"), 1),
 		OPT_SET_INT(0, "force-remove", &force_remove,
 			N_("remove named paths even if present in worktree"), 1),
-		OPT_SET_INT('z', NULL, &line_termination,
-			N_("with --stdin: input lines are terminated by null bytes"), '\0'),
+		OPT_BOOL('z', NULL, &nul_term_line,
+			 N_("with --stdin: input lines are terminated by null bytes")),
 		{OPTION_LOWLEVEL_CALLBACK, 0, "stdin", &read_from_stdin, NULL,
 			N_("read list of paths to be updated from standard input"),
 			PARSE_OPT_NONEG | PARSE_OPT_NOARG,
 			(parse_opt_cb *) stdin_callback},
-		{OPTION_LOWLEVEL_CALLBACK, 0, "index-info", &line_termination, NULL,
+		{OPTION_LOWLEVEL_CALLBACK, 0, "index-info", &nul_term_line, NULL,
 			N_("add entries from standard input to the index"),
 			PARSE_OPT_NONEG | PARSE_OPT_NOARG,
 			(parse_opt_cb *) stdin_cacheinfo_callback},
@@ -833,6 +1006,12 @@ int cmd_update_index(int argc, const char **argv, const char *prefix)
 			N_("write index in this format")),
 		OPT_BOOL(0, "split-index", &split_index,
 			N_("enable or disable split index")),
+		OPT_BOOL(0, "untracked-cache", &untracked_cache,
+			N_("enable/disable untracked cache")),
+		OPT_SET_INT(0, "test-untracked-cache", &untracked_cache,
+			    N_("test if the filesystem supports untracked cache"), UC_TEST),
+		OPT_SET_INT(0, "force-untracked-cache", &untracked_cache,
+			    N_("enable untracked cache without testing the filesystem"), UC_FORCE),
 		OPT_END()
 	};
 
@@ -871,14 +1050,14 @@ int cmd_update_index(int argc, const char **argv, const char *prefix)
 		case PARSE_OPT_DONE:
 		{
 			const char *path = ctx.argv[0];
-			const char *p;
+			char *p;
 
 			setup_work_tree();
 			p = prefix_path(prefix, prefix_length, path);
 			update_one(p);
 			if (set_executable_bit)
 				chmod_path(set_executable_bit, p);
-			free((char *)p);
+			free(p);
 			ctx.argc--;
 			ctx.argv++;
 			break;
@@ -892,6 +1071,8 @@ int cmd_update_index(int argc, const char **argv, const char *prefix)
 		}
 	}
 	argc = parse_options_end(&ctx);
+
+	getline_fn = nul_term_line ? strbuf_getline_nul : strbuf_getline_lf;
 	if (preferred_index_format) {
 		if (preferred_index_format < INDEX_FORMAT_LB ||
 		    INDEX_FORMAT_UB < preferred_index_format)
@@ -905,24 +1086,25 @@ int cmd_update_index(int argc, const char **argv, const char *prefix)
 	}
 
 	if (read_from_stdin) {
-		struct strbuf buf = STRBUF_INIT, nbuf = STRBUF_INIT;
+		struct strbuf buf = STRBUF_INIT;
+		struct strbuf unquoted = STRBUF_INIT;
 
 		setup_work_tree();
-		while (strbuf_getline(&buf, stdin, line_termination) != EOF) {
-			const char *p;
-			if (line_termination && buf.buf[0] == '"') {
-				strbuf_reset(&nbuf);
-				if (unquote_c_style(&nbuf, buf.buf, NULL))
+		while (getline_fn(&buf, stdin) != EOF) {
+			char *p;
+			if (!nul_term_line && buf.buf[0] == '"') {
+				strbuf_reset(&unquoted);
+				if (unquote_c_style(&unquoted, buf.buf, NULL))
 					die("line is badly quoted");
-				strbuf_swap(&buf, &nbuf);
+				strbuf_swap(&buf, &unquoted);
 			}
 			p = prefix_path(prefix, prefix_length, buf.buf);
 			update_one(p);
 			if (set_executable_bit)
 				chmod_path(set_executable_bit, p);
-			free((char *)p);
+			free(p);
 		}
-		strbuf_release(&nbuf);
+		strbuf_release(&unquoted);
 		strbuf_release(&buf);
 	}
 
@@ -940,6 +1122,33 @@ int cmd_update_index(int argc, const char **argv, const char *prefix)
 		the_index.cache_changed |= SOMETHING_CHANGED;
 	}
 
+	switch (untracked_cache) {
+	case UC_UNSPECIFIED:
+		break;
+	case UC_DISABLE:
+		if (git_config_get_untracked_cache() == 1)
+			warning("core.untrackedCache is set to true; "
+				"remove or change it, if you really want to "
+				"disable the untracked cache");
+		remove_untracked_cache(&the_index);
+		report(_("Untracked cache disabled"));
+		break;
+	case UC_TEST:
+		setup_work_tree();
+		return !test_if_untracked_cache_is_supported();
+	case UC_ENABLE:
+	case UC_FORCE:
+		if (git_config_get_untracked_cache() == 0)
+			warning("core.untrackedCache is set to false; "
+				"remove or change it, if you really want to "
+				"enable the untracked cache");
+		add_untracked_cache(&the_index);
+		report(_("Untracked cache enabled for '%s'"), get_git_work_tree());
+		break;
+	default:
+		die("Bug: bad untracked_cache value: %d", untracked_cache);
+	}
+
 	if (active_cache_changed) {
 		if (newfd < 0) {
 			if (refresh_args.flags & REFRESH_QUIET)