add: add --chmod=+x / --chmod=-x options

The executable bit will not be detected (and therefore will not be
set) for paths in a repository with `core.filemode` set to false,
though the users may still wish to add files as executable for
compatibility with other users who _do_ have `core.filemode`
functionality.  For example, Windows users adding shell scripts may
wish to add them as executable for compatibility with users on
non-Windows.

Although this can be done with a plumbing command
(`git update-index --add --chmod=+x foo`), teaching the `git-add`
command allows users to set a file executable with a command that
they're already familiar with.

Signed-off-by: Edward Thomson <ethomson@edwardthomson.com>
Helped-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

6 files changed, 68 insertions, 20 deletions

diff --git a/builtin/add.c b/builtin/add.c
index 145f06ef9..b1dddb4ac 100644
--- a/builtin/add.c
+++ b/builtin/add.c
@@ -26,7 +26,7 @@ static int patch_interactive, add_interactive, edit_interactive;
 static int take_worktree_changes;
 
 struct update_callback_data {
-	int flags;
+	int flags, force_mode;
 	int add_errors;
 };
 
@@ -65,7 +65,8 @@ static void update_callback(struct diff_queue_struct *q,
 			die(_("unexpected diff status %c"), p->status);
 		case DIFF_STATUS_MODIFIED:
 		case DIFF_STATUS_TYPE_CHANGED:
-			if (add_file_to_index(&the_index, path, data->flags)) {
+			if (add_file_to_index(&the_index, path,
+					data->flags, data->force_mode)) {
 				if (!(data->flags & ADD_CACHE_IGNORE_ERRORS))
 					die(_("updating files failed"));
 				data->add_errors++;
@@ -83,14 +84,15 @@ static void update_callback(struct diff_queue_struct *q,
 	}
 }
 
-int add_files_to_cache(const char *prefix,
-		       const struct pathspec *pathspec, int flags)
+int add_files_to_cache(const char *prefix, const struct pathspec *pathspec,
+	int flags, int force_mode)
 {
 	struct update_callback_data data;
 	struct rev_info rev;
 
 	memset(&data, 0, sizeof(data));
 	data.flags = flags;
+	data.force_mode = force_mode;
 
 	init_revisions(&rev, prefix);
 	setup_revisions(0, NULL, &rev, NULL);
@@ -238,6 +240,8 @@ static int ignore_add_errors, intent_to_add, ignore_missing;
 static int addremove = ADDREMOVE_DEFAULT;
 static int addremove_explicit = -1; /* unspecified */
 
+static char *chmod_arg;
+
 static int ignore_removal_cb(const struct option *opt, const char *arg, int unset)
 {
 	/* if we are told to ignore, we are not adding removals */
@@ -263,6 +267,7 @@ static struct option builtin_add_options[] = {
 	OPT_BOOL( 0 , "refresh", &refresh_only, N_("don't add, only refresh the index")),
 	OPT_BOOL( 0 , "ignore-errors", &ignore_add_errors, N_("just skip files which cannot be added because of errors")),
 	OPT_BOOL( 0 , "ignore-missing", &ignore_missing, N_("check if - even missing - files are ignored in dry run")),
+	OPT_STRING( 0 , "chmod", &chmod_arg, N_("(+/-)x"), N_("override the executable bit of the listed files")),
 	OPT_END(),
 };
 
@@ -276,7 +281,7 @@ static int add_config(const char *var, const char *value, void *cb)
 	return git_default_config(var, value, cb);
 }
 
-static int add_files(struct dir_struct *dir, int flags)
+static int add_files(struct dir_struct *dir, int flags, int force_mode)
 {
 	int i, exit_status = 0;
 
@@ -289,7 +294,8 @@ static int add_files(struct dir_struct *dir, int flags)
 	}
 
 	for (i = 0; i < dir->nr; i++)
-		if (add_file_to_cache(dir->entries[i]->name, flags)) {
+		if (add_file_to_index(&the_index, dir->entries[i]->name,
+				flags, force_mode)) {
 			if (!ignore_add_errors)
 				die(_("adding files failed"));
 			exit_status = 1;
@@ -302,7 +308,7 @@ int cmd_add(int argc, const char **argv, const char *prefix)
 	int exit_status = 0;
 	struct pathspec pathspec;
 	struct dir_struct dir;
-	int flags;
+	int flags, force_mode;
 	int add_new_files;
 	int require_pathspec;
 	char *seen = NULL;
@@ -336,6 +342,15 @@ int cmd_add(int argc, const char **argv, const char *prefix)
 	if (!show_only && ignore_missing)
 		die(_("Option --ignore-missing can only be used together with --dry-run"));
 
+	if (!chmod_arg)
+		force_mode = 0;
+	else if (!strcmp(chmod_arg, "-x"))
+		force_mode = 0666;
+	else if (!strcmp(chmod_arg, "+x"))
+		force_mode = 0777;
+	else
+		die(_("--chmod param '%s' must be either -x or +x"), chmod_arg);
+
 	add_new_files = !take_worktree_changes && !refresh_only;
 	require_pathspec = !(take_worktree_changes || (0 < addremove_explicit));
 
@@ -426,10 +441,10 @@ int cmd_add(int argc, const char **argv, const char *prefix)
 
 	plug_bulk_checkin();
 
-	exit_status |= add_files_to_cache(prefix, &pathspec, flags);
+	exit_status |= add_files_to_cache(prefix, &pathspec, flags, force_mode);
 
 	if (add_new_files)
-		exit_status |= add_files(&dir, flags);
+		exit_status |= add_files(&dir, flags, force_mode);
 
 	unplug_bulk_checkin();
 
diff --git a/builtin/checkout.c b/builtin/checkout.c
index 3398c61e9..c3486bdec 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -548,7 +548,7 @@ static int merge_working_tree(const struct checkout_opts *opts,
 			 * entries in the index.
 			 */
 
-			add_files_to_cache(NULL, NULL, 0);
+			add_files_to_cache(NULL, NULL, 0, 0);
 			/*
 			 * NEEDSWORK: carrying over local changes
 			 * when branches have different end-of-line
diff --git a/builtin/commit.c b/builtin/commit.c
index 443ff9196..163dbcabf 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -386,7 +386,7 @@ static const char *prepare_index(int argc, const char **argv, const char *prefix
 	 */
 	if (all || (also && pathspec.nr)) {
 		hold_locked_index(&index_lock, 1);
-		add_files_to_cache(also ? prefix : NULL, &pathspec, 0);
+		add_files_to_cache(also ? prefix : NULL, &pathspec, 0, 0);
 		refresh_cache_or_die(refresh_flags);
 		update_main_cache_tree(WRITE_TREE_SILENT);
 		if (write_locked_index(&the_index, &index_lock, CLOSE_LOCK))
diff --git a/cache.h b/cache.h
index 6049f8671..c73becbf2 100644
--- a/cache.h
+++ b/cache.h
@@ -367,8 +367,8 @@ extern void free_name_hash(struct index_state *istate);
 #define rename_cache_entry_at(pos, new_name) rename_index_entry_at(&the_index, (pos), (new_name))
 #define remove_cache_entry_at(pos) remove_index_entry_at(&the_index, (pos))
 #define remove_file_from_cache(path) remove_file_from_index(&the_index, (path))
-#define add_to_cache(path, st, flags) add_to_index(&the_index, (path), (st), (flags))
-#define add_file_to_cache(path, flags) add_file_to_index(&the_index, (path), (flags))
+#define add_to_cache(path, st, flags) add_to_index(&the_index, (path), (st), (flags), 0)
+#define add_file_to_cache(path, flags) add_file_to_index(&the_index, (path), (flags), 0)
 #define refresh_cache(flags) refresh_index(&the_index, (flags), NULL, NULL, NULL)
 #define ce_match_stat(ce, st, options) ie_match_stat(&the_index, (ce), (st), (options))
 #define ce_modified(ce, st, options) ie_modified(&the_index, (ce), (st), (options))
@@ -581,8 +581,8 @@ extern int remove_file_from_index(struct index_state *, const char *path);
 #define ADD_CACHE_IGNORE_ERRORS	4
 #define ADD_CACHE_IGNORE_REMOVAL 8
 #define ADD_CACHE_INTENT 16
-extern int add_to_index(struct index_state *, const char *path, struct stat *, int flags);
-extern int add_file_to_index(struct index_state *, const char *path, int flags);
+extern int add_to_index(struct index_state *, const char *path, struct stat *, int flags, int force_mode);
+extern int add_file_to_index(struct index_state *, const char *path, int flags, int force_mode);
 extern struct cache_entry *make_cache_entry(unsigned int mode, const unsigned char *sha1, const char *path, int stage, unsigned int refresh_options);
 extern int ce_same_name(const struct cache_entry *a, const struct cache_entry *b);
 extern void set_object_name_for_intent_to_add_entry(struct cache_entry *ce);
@@ -1772,7 +1772,7 @@ void packet_trace_identity(const char *prog);
  * return 0 if success, 1 - if addition of a file failed and
  * ADD_FILES_IGNORE_ERRORS was specified in flags
  */
-int add_files_to_cache(const char *prefix, const struct pathspec *pathspec, int flags);
+int add_files_to_cache(const char *prefix, const struct pathspec *pathspec, int flags, int force_mode);
 
 /* diff.c */
 extern int diff_auto_refresh_index;
diff --git a/read-cache.c b/read-cache.c
index d9fb78bc5..db2776605 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -630,7 +630,7 @@ void set_object_name_for_intent_to_add_entry(struct cache_entry *ce)
 	hashcpy(ce->sha1, sha1);
 }
 
-int add_to_index(struct index_state *istate, const char *path, struct stat *st, int flags)
+int add_to_index(struct index_state *istate, const char *path, struct stat *st, int flags, int force_mode)
 {
 	int size, namelen, was_same;
 	mode_t st_mode = st->st_mode;
@@ -659,7 +659,9 @@ int add_to_index(struct index_state *istate, const char *path, struct stat *st,
 	else
 		ce->ce_flags |= CE_INTENT_TO_ADD;
 
-	if (trust_executable_bit && has_symlinks)
+	if (S_ISREG(st_mode) && force_mode)
+		ce->ce_mode = create_ce_mode(force_mode);
+	else if (trust_executable_bit && has_symlinks)
 		ce->ce_mode = create_ce_mode(st_mode);
 	else {
 		/* If there is an existing entry, pick the mode bits and type
@@ -720,12 +722,13 @@ int add_to_index(struct index_state *istate, const char *path, struct stat *st,
 	return 0;
 }
 
-int add_file_to_index(struct index_state *istate, const char *path, int flags)
+int add_file_to_index(struct index_state *istate, const char *path,
+	int flags, int force_mode)
 {
 	struct stat st;
 	if (lstat(path, &st))
 		die_errno("unable to stat '%s'", path);
-	return add_to_index(istate, path, &st, flags);
+	return add_to_index(istate, path, &st, flags, force_mode);
 }
 
 struct cache_entry *make_cache_entry(unsigned int mode,
diff --git a/t/t3700-add.sh b/t/t3700-add.sh
index f14a66535..4865304eb 100755
--- a/t/t3700-add.sh
+++ b/t/t3700-add.sh
@@ -332,4 +332,34 @@ test_expect_success 'git add --dry-run --ignore-missing of non-existing file out
 	test_i18ncmp expect.err actual.err
 '
 
+test_expect_success 'git add --chmod=+x stages a non-executable file with +x' '
+	echo foo >foo1 &&
+	git add --chmod=+x foo1 &&
+	case "$(git ls-files --stage foo1)" in
+	100755" "*foo1) echo pass;;
+	*) echo fail; git ls-files --stage foo1; (exit 1);;
+	esac
+'
+
+test_expect_success 'git add --chmod=-x stages an executable file with -x' '
+	echo foo >xfoo1 &&
+	chmod 755 xfoo1 &&
+	git add --chmod=-x xfoo1 &&
+	case "$(git ls-files --stage xfoo1)" in
+	100644" "*xfoo1) echo pass;;
+	*) echo fail; git ls-files --stage xfoo1; (exit 1);;
+	esac
+'
+
+test_expect_success POSIXPERM,SYMLINKS 'git add --chmod=+x with symlinks' '
+	git config core.filemode 1 &&
+	git config core.symlinks 1 &&
+	echo foo >foo2 &&
+	git add --chmod=+x foo2 &&
+	case "$(git ls-files --stage foo2)" in
+	100755" "*foo2) echo pass;;
+	*) echo fail; git ls-files --stage foo2; (exit 1);;
+	esac
+'
+
 test_done