+#if ENABLE_HUSH_UNSET
+/* http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#unset */
+static int FAST_FUNC builtin_unset(char **argv)
+{
+ int ret;
+ unsigned opts;
+
+ /* "!": do not abort on errors */
+ /* "+": stop at 1st non-option */
+ opts = getopt32(argv, "!+vf");
+ if (opts == (unsigned)-1)
+ return EXIT_FAILURE;
+ if (opts == 3) {
+ bb_error_msg("unset: -v and -f are exclusive");
+ return EXIT_FAILURE;
+ }
+ argv += optind;
+
+ ret = EXIT_SUCCESS;
+ while (*argv) {
+ if (!(opts & 2)) { /* not -f */
+ if (unset_local_var(*argv)) {
+ /* unset <nonexistent_var> doesn't fail.
+ * Error is when one tries to unset RO var.
+ * Message was printed by unset_local_var. */
+ ret = EXIT_FAILURE;
+ }
+ }
+# if ENABLE_HUSH_FUNCTIONS
+ else {
+ unset_func(*argv);
+ }
+# endif
+ argv++;
+ }
+ return ret;
+}
+#endif
+
+#if ENABLE_HUSH_SET
+/* http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#set
+ * built-in 'set' handler
+ * SUSv3 says:
+ * set [-abCefhmnuvx] [-o option] [argument...]
+ * set [+abCefhmnuvx] [+o option] [argument...]
+ * set -- [argument...]
+ * set -o
+ * set +o
+ * Implementations shall support the options in both their hyphen and
+ * plus-sign forms. These options can also be specified as options to sh.
+ * Examples:
+ * Write out all variables and their values: set
+ * Set $1, $2, and $3 and set "$#" to 3: set c a b
+ * Turn on the -x and -v options: set -xv
+ * Unset all positional parameters: set --
+ * Set $1 to the value of x, even if it begins with '-' or '+': set -- "$x"
+ * Set the positional parameters to the expansion of x, even if x expands
+ * with a leading '-' or '+': set -- $x
+ *
+ * So far, we only support "set -- [argument...]" and some of the short names.
+ */
+static int FAST_FUNC builtin_set(char **argv)
+{
+ int n;
+ char **pp, **g_argv;
+ char *arg = *++argv;
+
+ if (arg == NULL) {
+ struct variable *e;
+ for (e = G.top_var; e; e = e->next)
+ puts(e->varstr);
+ return EXIT_SUCCESS;
+ }
+
+ do {
+ if (strcmp(arg, "--") == 0) {
+ ++argv;
+ goto set_argv;
+ }
+ if (arg[0] != '+' && arg[0] != '-')
+ break;
+ for (n = 1; arg[n]; ++n) {
+ if (set_mode((arg[0] == '-'), arg[n], argv[1]))
+ goto error;
+ if (arg[n] == 'o' && argv[1])
+ argv++;
+ }
+ } while ((arg = *++argv) != NULL);
+ /* Now argv[0] is 1st argument */
+
+ if (arg == NULL)
+ return EXIT_SUCCESS;
+ set_argv:
+
+ /* NB: G.global_argv[0] ($0) is never freed/changed */
+ g_argv = G.global_argv;
+ if (G.global_args_malloced) {
+ pp = g_argv;
+ while (*++pp)
+ free(*pp);
+ g_argv[1] = NULL;
+ } else {
+ G.global_args_malloced = 1;
+ pp = xzalloc(sizeof(pp[0]) * 2);
+ pp[0] = g_argv[0]; /* retain $0 */
+ g_argv = pp;
+ }
+ /* This realloc's G.global_argv */
+ G.global_argv = pp = add_strings_to_strings(g_argv, argv, /*dup:*/ 1);
+
+ n = 1;
+ while (*++pp)
+ n++;
+ G.global_argc = n;
+
+ return EXIT_SUCCESS;
+
+ /* Nothing known, so abort */
+ error:
+ bb_error_msg("set: %s: invalid option", arg);
+ return EXIT_FAILURE;
+}
+#endif
+
+static int FAST_FUNC builtin_shift(char **argv)
+{
+ int n = 1;
+ argv = skip_dash_dash(argv);
+ if (argv[0]) {
+ n = atoi(argv[0]);
+ }
+ if (n >= 0 && n < G.global_argc) {
+ if (G_global_args_malloced) {
+ int m = 1;
+ while (m <= n)
+ free(G.global_argv[m++]);
+ }
+ G.global_argc -= n;
+ memmove(&G.global_argv[1], &G.global_argv[n+1],
+ G.global_argc * sizeof(G.global_argv[0]));
+ return EXIT_SUCCESS;
+ }
+ return EXIT_FAILURE;
+}
+
+static int FAST_FUNC builtin_source(char **argv)
+{
+ char *arg_path, *filename;
+ FILE *input;
+ save_arg_t sv;
+ char *args_need_save;
+#if ENABLE_HUSH_FUNCTIONS
+ smallint sv_flg;
+#endif
+
+ argv = skip_dash_dash(argv);
+ filename = argv[0];
+ if (!filename) {
+ /* bash says: "bash: .: filename argument required" */
+ return 2; /* bash compat */
+ }
+ arg_path = NULL;
+ if (!strchr(filename, '/')) {
+ arg_path = find_in_path(filename);
+ if (arg_path)
+ filename = arg_path;
+ }
+ input = remember_FILE(fopen_or_warn(filename, "r"));
+ free(arg_path);
+ if (!input) {
+ /* bb_perror_msg("%s", *argv); - done by fopen_or_warn */
+ /* POSIX: non-interactive shell should abort here,
+ * not merely fail. So far no one complained :)
+ */
+ return EXIT_FAILURE;
+ }
+
+#if ENABLE_HUSH_FUNCTIONS
+ sv_flg = G_flag_return_in_progress;
+ /* "we are inside sourced file, ok to use return" */
+ G_flag_return_in_progress = -1;
+#endif
+ args_need_save = argv[1]; /* used as a boolean variable */
+ if (args_need_save)
+ save_and_replace_G_args(&sv, argv);
+
+ /* "false; . ./empty_line; echo Zero:$?" should print 0 */
+ G.last_exitcode = 0;
+ parse_and_run_file(input);
+ fclose_and_forget(input);
+
+ if (args_need_save) /* can't use argv[1] instead: "shift" can mangle it */
+ restore_G_args(&sv, argv);
+#if ENABLE_HUSH_FUNCTIONS
+ G_flag_return_in_progress = sv_flg;
+#endif
+
+ return G.last_exitcode;
+}
+
+#if ENABLE_HUSH_TRAP