[git commit] setfattr: new applet

[Denys Vlasenko]

commit: https://git.busybox.net/busybox/commit/?id=b278ac0e607aa971c46706be63c580a2fd88dd56
branch: https://git.busybox.net/busybox/commit/?id=refs/heads/master

function                                             old     new   delta
setfattr_main                                          -     189    +189
packed_usage                                       31516   31588     +72
setxattr                                               -      53     +53
lsetxattr                                              -      53     +53
removexattr                                            -      37     +37
lremovexattr                                           -      37     +37
applet_names                                        2649    2658      +9
find_applet_by_name                                  124     128      +4
applet_main                                         1532    1536      +4
------------------------------------------------------------------------------
(add/remove: 7/0 grow/shrink: 4/0 up/down: 458/0)             Total: 458 bytes

Signed-off-by: Denys Vlasenko <vda.linux at googlemail.com>
---
 miscutils/setfattr.c | 68 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 68 insertions(+)

diff --git a/miscutils/setfattr.c b/miscutils/setfattr.c
new file mode 100644
index 0000000..f0ef227
--- /dev/null
+++ b/miscutils/setfattr.c
@@ -0,0 +1,68 @@
+/*
+ * setfattr - set extended attributes of filesystem objects.
+ *
+ * Copyright (C) 2017 by Denys Vlasenko <vda.linux at googlemail.com>
+ *
+ * Licensed under GPLv2, see file LICENSE in this source tree.
+ */
+//config:config SETFATTR
+//config:	bool "setfattr"
+//config:	default y
+//config:	help
+//config:	Set/delete extended attributes on files
+
+//applet:IF_SETFATTR(APPLET_NOEXEC(setfattr, setfattr, BB_DIR_USR_BIN, BB_SUID_DROP, setfattr))
+
+//kbuild:lib-$(CONFIG_SETFATTR) += setfattr.o
+
+#include <sys/xattr.h>
+#include "libbb.h"
+
+//usage:#define setfattr_trivial_usage
+//usage:       "[-h] -n|-x ATTR [-v VALUE] FILE..."
+//usage:#define setfattr_full_usage "\n\n"
+//usage:       "Set extended attributes"
+//usage:     "\n"
+//usage:     "\n	-h		Do not follow symlinks"
+//usage:     "\n	-x ATTR		Remove attribute ATTR"
+//usage:     "\n	-n ATTR		Set attribute ATTR to VALUE"
+//usage:     "\n	-v VALUE	(default: empty)"
+int setfattr_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int setfattr_main(int argc UNUSED_PARAM, char **argv)
+{
+	const char *name;
+	const char *value = "";
+	int status;
+	int opt;
+	enum {
+		OPT_h = (1 << 0),
+		OPT_x = (1 << 1),
+	};
+
+	opt = getopt32(argv, "^"
+		"hx:n:v:"
+		/* Min one arg, either -x or -n is a must, -x does not allow -v */
+		"\0" "-1:x:n:n--x:x--nv:v--x"
+		, &name, &name, &value
+	);
+	argv += optind;
+
+	status = EXIT_SUCCESS;
+	do {
+		int r;
+		if (opt & OPT_x)
+			r = ((opt & OPT_h) ? lremovexattr : removexattr)(*argv, name);
+		else {
+			r = ((opt & OPT_h) ? lsetxattr : setxattr)(
+					*argv, name,
+					value, strlen(value), /*flags:*/ 0
+			);
+		}
+		if (r) {
+			bb_simple_perror_msg(*argv);
+			status = EXIT_FAILURE;
+		}
+	} while (*++argv);
+
+	return status;
+}