hush: cleanup pass, the biggest is - moved builtins to the end of the file,

 they really annoy in the middle of parser code. no real code changes.

2 files changed, 358 insertions, 355 deletions

diff --git a/shell/hush.c b/shell/hush.c
index 0b92c29d4..e64cc476d 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -244,7 +244,6 @@ typedef enum {
         PIPE_BG  = 4,
 } pipe_style;
 
-/* might eventually control execution */
 typedef enum {
         RES_NONE  = 0,
 #if ENABLE_HUSH_IF
@@ -265,6 +264,7 @@ typedef enum {
         RES_XXXX  = 12,
         RES_SNTX  = 13
 } reserved_style;
+
 /* This holds pointers to the various results of parsing */
 struct p_context {
         struct child_prog *child;
@@ -298,6 +298,7 @@ struct child_prog {
  * and on execution these are substituted with their values.
  * Substitution can make _several_ words out of one argv[n]!
  * Example: argv[0]=='.^C*^C.' here: echo .$*.
+ * References of the form ^C`cmd arg^C are `cmd arg` substitutions.
  */
 
 struct pipe {
@@ -341,8 +342,8 @@ typedef struct {
         smallint nonnull;
         smallint has_empty_slot;
 } o_string;
+/* Used for initialization: o_string foo = NULL_O_STRING; */
 #define NULL_O_STRING { NULL }
-/* used for initialization: o_string foo = NULL_O_STRING; */
 
 /* I can almost use ordinary FILE *.  Is open_memstream() universally
  * available?  Where is it documented? */
@@ -572,7 +573,7 @@ static int glob_needed(const char *s)
         return 0;
 }
 
-static char **add_strings_to_strings(int need_xstrdup, char **strings, char **add)
+static char **add_malloced_strings_to_strings(char **strings, char **add)
 {
         int i;
         unsigned count1;
@@ -597,19 +598,18 @@ static char **add_strings_to_strings(int need_xstrdup, char **strings, char **ad
         v[count1 + count2] = NULL;
         i = count2;
         while (--i >= 0)
-                v[count1 + i] = need_xstrdup ? xstrdup(add[i]) : add[i];
+                v[count1 + i] = add[i];
         return v;
 }
 
-/* 'add' should be a malloced pointer */
-static char **add_string_to_strings(char **strings, char *add)
+static char **add_malloced_string_to_strings(char **strings, char *add)
 {
         char *v[2];
 
         v[0] = add;
         v[1] = NULL;
 
-        return add_strings_to_strings(0, strings, v);
+        return add_malloced_strings_to_strings(strings, v);
 }
 
 static void free_strings(char **strings)
@@ -713,6 +713,7 @@ static const struct built_in_command bltins[] = {
 #endif
 };
 
+
 /* Signals are grouped, we handle them in batches */
 static void set_misc_sighandler(void (*handler)(int))
 {
@@ -846,333 +847,6 @@ static const char *set_cwd(void)
 }
 
 
-/* built-in 'true' handler */
-static int builtin_true(char **argv ATTRIBUTE_UNUSED)
-{
-        return 0;
-}
-
-/* built-in 'test' handler */
-static int builtin_test(char **argv)
-{
-        int argc = 0;
-        while (*argv) {
-                argc++;
-                argv++;
-        }
-        return test_main(argc, argv - argc);
-}
-
-/* built-in 'test' handler */
-static int builtin_echo(char **argv)
-{
-        int argc = 0;
-        while (*argv) {
-                argc++;
-                argv++;
-        }
-        return echo_main(argc, argv - argc);
-}
-
-/* built-in 'eval' handler */
-static int builtin_eval(char **argv)
-{
-        int rcode = EXIT_SUCCESS;
-
-        if (argv[1]) {
-                char *str = expand_strvec_to_string(argv + 1);
-                parse_and_run_string(str, PARSEFLAG_EXIT_FROM_LOOP);
-                free(str);
-                rcode = last_return_code;
-        }
-        return rcode;
-}
-
-/* built-in 'cd <path>' handler */
-static int builtin_cd(char **argv)
-{
-        const char *newdir;
-        if (argv[1] == NULL) {
-                // bash does nothing (exitcode 0) if HOME is ""; if it's unset,
-                // bash says "bash: cd: HOME not set" and does nothing (exitcode 1)
-                newdir = getenv("HOME") ? : "/";
-        } else
-                newdir = argv[1];
-        if (chdir(newdir)) {
-                printf("cd: %s: %s\n", newdir, strerror(errno));
-                return EXIT_FAILURE;
-        }
-        set_cwd();
-        return EXIT_SUCCESS;
-}
-
-/* built-in 'exec' handler */
-static int builtin_exec(char **argv)
-{
-        if (argv[1] == NULL)
-                return EXIT_SUCCESS; /* bash does this */
-        {
-#if !BB_MMU
-                char **ptrs2free = alloc_ptrs(argv);
-#endif
-// FIXME: if exec fails, bash does NOT exit! We do...
-                pseudo_exec_argv(ptrs2free, argv + 1);
-                /* never returns */
-        }
-}
-
-/* built-in 'exit' handler */
-static int builtin_exit(char **argv)
-{
-// TODO: bash does it ONLY on top-level sh exit (+interacive only?)
-        //puts("exit"); /* bash does it */
-// TODO: warn if we have background jobs: "There are stopped jobs"
-// On second consecutive 'exit', exit anyway.
-        if (argv[1] == NULL)
-                hush_exit(last_return_code);
-        /* mimic bash: exit 123abc == exit 255 + error msg */
-        xfunc_error_retval = 255;
-        /* bash: exit -2 == exit 254, no error msg */
-        hush_exit(xatoi(argv[1]) & 0xff);
-}
-
-/* built-in 'export VAR=value' handler */
-static int builtin_export(char **argv)
-{
-        const char *value;
-        char *name = argv[1];
-
-        if (name == NULL) {
-                // TODO:
-                // ash emits: export VAR='VAL'
-                // bash: declare -x VAR="VAL"
-                // (both also escape as needed (quotes, $, etc))
-                char **e = environ;
-                if (e)
-                        while (*e)
-                                puts(*e++);
-                return EXIT_SUCCESS;
-        }
-
-        value = strchr(name, '=');
-        if (!value) {
-                /* They are exporting something without a =VALUE */
-                struct variable *var;
-
-                var = get_local_var(name);
-                if (var) {
-                        var->flg_export = 1;
-                        putenv(var->varstr);
-                }
-                /* bash does not return an error when trying to export
-                 * an undefined variable.  Do likewise. */
-                return EXIT_SUCCESS;
-        }
-
-        set_local_var(xstrdup(name), 1);
-        return EXIT_SUCCESS;
-}
-
-#if ENABLE_HUSH_JOB
-/* built-in 'fg' and 'bg' handler */
-static int builtin_fg_bg(char **argv)
-{
-        int i, jobnum;
-        struct pipe *pi;
-
-        if (!interactive_fd)
-                return EXIT_FAILURE;
-        /* If they gave us no args, assume they want the last backgrounded task */
-        if (!argv[1]) {
-                for (pi = job_list; pi; pi = pi->next) {
-                        if (pi->jobid == last_jobid) {
-                                goto found;
-                        }
-                }
-                bb_error_msg("%s: no current job", argv[0]);
-                return EXIT_FAILURE;
-        }
-        if (sscanf(argv[1], "%%%d", &jobnum) != 1) {
-                bb_error_msg("%s: bad argument '%s'", argv[0], argv[1]);
-                return EXIT_FAILURE;
-        }
-        for (pi = job_list; pi; pi = pi->next) {
-                if (pi->jobid == jobnum) {
-                        goto found;
-                }
-        }
-        bb_error_msg("%s: %d: no such job", argv[0], jobnum);
-        return EXIT_FAILURE;
- found:
-        // TODO: bash prints a string representation
-        // of job being foregrounded (like "sleep 1 | cat")
-        if (*argv[0] == 'f') {
-                /* Put the job into the foreground.  */
-                tcsetpgrp(interactive_fd, pi->pgrp);
-        }
-
-        /* Restart the processes in the job */
-        debug_printf_jobs("reviving %d procs, pgrp %d\n", pi->num_progs, pi->pgrp);
-        for (i = 0; i < pi->num_progs; i++) {
-                debug_printf_jobs("reviving pid %d\n", pi->progs[i].pid);
-                pi->progs[i].is_stopped = 0;
-        }
-        pi->stopped_progs = 0;
-
-        i = kill(- pi->pgrp, SIGCONT);
-        if (i < 0) {
-                if (errno == ESRCH) {
-                        delete_finished_bg_job(pi);
-                        return EXIT_SUCCESS;
-                } else {
-                        bb_perror_msg("kill (SIGCONT)");
-                }
-        }
-
-        if (*argv[0] == 'f') {
-                remove_bg_job(pi);
-                return checkjobs_and_fg_shell(pi);
-        }
-        return EXIT_SUCCESS;
-}
-#endif
-
-/* built-in 'help' handler */
-#if ENABLE_HUSH_HELP
-static int builtin_help(char **argv ATTRIBUTE_UNUSED)
-{
-        const struct built_in_command *x;
-
-        printf("\nBuilt-in commands:\n");
-        printf("-------------------\n");
-        for (x = bltins; x != &bltins[ARRAY_SIZE(bltins)]; x++) {
-                printf("%s\t%s\n", x->cmd, x->descr);
-        }
-        printf("\n\n");
-        return EXIT_SUCCESS;
-}
-#endif
-
-#if ENABLE_HUSH_JOB
-/* built-in 'jobs' handler */
-static int builtin_jobs(char **argv ATTRIBUTE_UNUSED)
-{
-        struct pipe *job;
-        const char *status_string;
-
-        for (job = job_list; job; job = job->next) {
-                if (job->running_progs == job->stopped_progs)
-                        status_string = "Stopped";
-                else
-                        status_string = "Running";
-
-                printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->cmdtext);
-        }
-        return EXIT_SUCCESS;
-}
-#endif
-
-/* built-in 'pwd' handler */
-static int builtin_pwd(char **argv ATTRIBUTE_UNUSED)
-{
-        puts(set_cwd());
-        return EXIT_SUCCESS;
-}
-
-/* built-in 'read VAR' handler */
-static int builtin_read(char **argv)
-{
-        char *string;
-        const char *name = argv[1] ? argv[1] : "REPLY";
-
-        string = xmalloc_reads(STDIN_FILENO, xasprintf("%s=", name), NULL);
-        return set_local_var(string, 0);
-}
-
-/* built-in 'set [VAR=value]' handler */
-static int builtin_set(char **argv)
-{
-        char *temp = argv[1];
-        struct variable *e;
-
-        if (temp == NULL)
-                for (e = top_var; e; e = e->next)
-                        puts(e->varstr);
-        else
-                set_local_var(xstrdup(temp), 0);
-
-        return EXIT_SUCCESS;
-}
-
-
-/* Built-in 'shift' handler */
-static int builtin_shift(char **argv)
-{
-        int n = 1;
-        if (argv[1]) {
-                n = atoi(argv[1]);
-        }
-        if (n >= 0 && n < global_argc) {
-                global_argv[n] = global_argv[0];
-                global_argc -= n;
-                global_argv += n;
-                return EXIT_SUCCESS;
-        }
-        return EXIT_FAILURE;
-}
-
-/* Built-in '.' handler (read-in and execute commands from file) */
-static int builtin_source(char **argv)
-{
-        FILE *input;
-        int status;
-
-        if (argv[1] == NULL)
-                return EXIT_FAILURE;
-
-        /* XXX search through $PATH is missing */
-        input = fopen(argv[1], "r");
-        if (!input) {
-                bb_error_msg("cannot open '%s'", argv[1]);
-                return EXIT_FAILURE;
-        }
-        close_on_exec_on(fileno(input));
-
-        /* Now run the file */
-        /* XXX argv and argc are broken; need to save old global_argv
-         * (pointer only is OK!) on this stack frame,
-         * set global_argv=argv+1, recurse, and restore. */
-        status = parse_and_run_file(input);
-        fclose(input);
-        return status;
-}
-
-static int builtin_umask(char **argv)
-{
-        mode_t new_umask;
-        const char *arg = argv[1];
-        char *end;
-        if (arg) {
-                new_umask = strtoul(arg, &end, 8);
-                if (*end != '\0' || end == arg) {
-                        return EXIT_FAILURE;
-                }
-        } else {
-                new_umask = umask(0);
-                printf("%.3o\n", (unsigned) new_umask);
-        }
-        umask(new_umask);
-        return EXIT_SUCCESS;
-}
-
-/* built-in 'unset VAR' handler */
-static int builtin_unset(char **argv)
-{
-        /* bash always returns true */
-        unset_local_var(argv[1]);
-        return EXIT_SUCCESS;
-}
-
 /*
  * o_string support
  */
@@ -1282,7 +956,7 @@ static void o_addQstr(o_string *o, const char *str, int len)
 
 /* A special kind of o_string for $VAR and `cmd` expansion.
  * It contains char* list[] at the beginning, which is grown in 16 element
- * increments. Actual string data starts at the next multiple of 16.
+ * increments. Actual string data starts at the next multiple of 16 * (char*).
  * list[i] contains an INDEX (int!) into this string data.
  * It means that if list[] needs to grow, data needs to be moved higher up
  * but list[i]'s need not be modified.
@@ -1355,7 +1029,8 @@ static int o_get_last_ptr(o_string *o, int n)
         return ((int)list[n-1]) + string_start;
 }
 
-/* Convert every \x to x in-place, return ptr past NUL. */
+/* o_glob performs globbing on last list[], saving each result
+ * as a new list[]. unbackslash() is just a helper */
 static char *unbackslash(char *src)
 {
         char *dst = src;
@@ -1367,7 +1042,6 @@ static char *unbackslash(char *src)
         }
         return dst;
 }
-
 static int o_glob(o_string *o, int n)
 {
         glob_t globdata;
@@ -1416,8 +1090,8 @@ static int o_glob(o_string *o, int n)
         return n;
 }
 
-/* o_save_ptr_helper + but glob the string so far remembered
- * if o->o_glob == 1 */
+/* If o->o_glob == 1, glob the string so far remembered.
+ * Otherwise, just finish current list[] and start new */
 static int o_save_ptr(o_string *o, int n)
 {
         if (o->o_glob)
@@ -1462,6 +1136,7 @@ static int static_peek(struct in_str *i)
 }
 
 #if ENABLE_HUSH_INTERACTIVE
+
 #if ENABLE_FEATURE_EDITING
 static void cmdedit_set_initial_prompt(void)
 {
@@ -1521,6 +1196,7 @@ static void get_user_input(struct in_str *i)
 #endif
         i->p = user_input_buf;
 }
+
 #endif  /* INTERACTIVE */
 
 /* This is the magic location that prints prompts
@@ -1604,6 +1280,7 @@ static void setup_string_in_str(struct in_str *i, const char *s)
         i->eof_flag = 0;
 }
 
+
 /* squirrel != NULL means we squirrel away copies of stdin, stdout,
  * and stderr if they are redirected. */
 static int setup_redirects(struct child_prog *prog, int squirrel[])
@@ -1659,6 +1336,7 @@ static void restore_redirects(int squirrel[])
         }
 }
 
+
 /* Called after [v]fork() in run_pipe(), or from builtin_exec().
  * Never returns.
  * XXX no exit() here.  If you don't exec, use _exit instead.
@@ -2589,6 +2267,7 @@ static int run_and_free_list(struct pipe *pi)
         return rcode;
 }
 
+
 /* expand_strvec_to_strvec() takes a list of strings, expands
  * all variable references within and returns a pointer to
  * a list of expanded strings, possibly with larger number
@@ -2737,7 +2416,9 @@ static int expand_vars_to_list(o_string *output, int n, char *arg, char or_mask)
                         } else
                                 val = lookup_param(arg);
                         arg[0] = first_ch;
+#if ENABLE_HUSH_TICK
  store_val:
+#endif
                         *p = SPECIAL_VAR_SYMBOL;
                         if (!(first_ch & 0x80)) { /* unquoted $VAR */
                                 if (val) {
@@ -2801,7 +2482,7 @@ static char **expand_strvec_to_strvec(char **argv)
         return expand_variables(argv, 0x100);
 }
 
-/* used for expansion of right hand of assignments */
+/* Used for expansion of right hand of assignments */
 /* NB: should NOT do globbing! "export v=/bin/c*; env | grep ^v=" outputs
  * "v=/bin/c*" */
 static char *expand_string_to_string(const char *str)
@@ -2820,7 +2501,7 @@ static char *expand_string_to_string(const char *str)
         return (char*)list;
 }
 
-/* used for eval */
+/* Used for "eval" builtin */
 static char* expand_strvec_to_string(char **argv)
 {
         char **list;
@@ -2842,7 +2523,8 @@ static char* expand_strvec_to_string(char **argv)
         return (char*)list;
 }
 
-/* This is used to get/check local shell variables */
+
+/* Used to get/check local shell variables */
 static struct variable *get_local_var(const char *name)
 {
         struct variable *cur;
@@ -3099,12 +2781,16 @@ static int reserved_word(const o_string *word, struct p_context *ctx)
                         continue;
                 debug_printf("found reserved word %s, res %d\n", r->literal, r->res);
                 if (r->flag == 0) { /* '!' */
+#if ENABLE_HUSH_LOOPS
                         if (ctx->res_w == RES_IN) {
                                 /* 'for a in ! a b c; ...' - ! isn't a keyword here */
                                 break;
                         }
-                        if (ctx->res_w == RES_FOR /* example: 'for ! a' */
-                         || ctx->ctx_inverted /* bash doesn't accept '! ! true' */
+#endif
+                        if (ctx->ctx_inverted /* bash doesn't accept '! ! true' */
+#if ENABLE_HUSH_LOOPS
+                         || ctx->res_w == RES_FOR /* example: 'for ! a' */
+#endif
                         ) {
                                 syntax(NULL);
                                 ctx->res_w = RES_SNTX;
@@ -3152,8 +2838,7 @@ static int reserved_word(const o_string *word, struct p_context *ctx)
 #endif
 
 /* Word is complete, look at it and update parsing context.
- * Normal return is 0.
- * Syntax or xglob errors return 1. */
+ * Normal return is 0. Syntax errors return 1. */
 static int done_word(o_string *word, struct p_context *ctx)
 {
         struct child_prog *child = ctx->child;
@@ -3184,7 +2869,7 @@ static int done_word(o_string *word, struct p_context *ctx)
         }
 
         if (word->length || word->nonnull) {
-                *glob_target = add_string_to_strings(*glob_target, xstrdup(word->data));
+                *glob_target = add_malloced_string_to_strings(*glob_target, xstrdup(word->data));
                 debug_print_strings("glob_target appended", *glob_target);
         }
 
@@ -3282,9 +2967,9 @@ static void done_pipe(struct p_context *ctx, pipe_style type)
         debug_printf_parse("done_pipe return\n");
 }
 
-/* peek ahead in the in_str to find out if we have a "&n" construct,
+/* Peek ahead in the in_str to find out if we have a "&n" construct,
  * as in "2>&1", that represents duplicating a file descriptor.
- * returns either -2 (syntax error), -1 (no &), or the number found.
+ * Return either -2 (syntax error), -1 (no &), or the number found.
  */
 static int redirect_dup_num(struct in_str *input)
 {
@@ -3395,7 +3080,7 @@ static int process_command_subs(o_string *dest,
 
         initialize_context(&inner);
 
-        /* recursion to generate command */
+        /* Recursion to generate command */
         retcode = parse_stream(&result, &inner, input, subst_end);
         if (retcode != 0)
                 return retcode;  /* syntax error or EOF */
@@ -3409,7 +3094,7 @@ static int process_command_subs(o_string *dest,
         close_on_exec_on(fileno(p));
         setup_file_in_str(&pipe_str, p);
 
-        /* now send results of command back into original context */
+        /* Now send results of command back into original context */
         eol_cnt = 0;
         while ((ch = i_getch(&pipe_str)) != EOF) {
                 if (ch == '\n') {
@@ -3596,7 +3281,7 @@ static void add_till_closing_curly_brace(o_string *dest, struct in_str *input)
 }
 #endif /* ENABLE_HUSH_TICK */
 
-/* return code: 0 for OK, 1 for syntax error */
+/* Return code: 0 for OK, 1 for syntax error */
 static int handle_dollar(o_string *dest, struct in_str *input)
 {
         int ch = i_peek(input);  /* first character after the $ */
@@ -3674,7 +3359,7 @@ static int handle_dollar(o_string *dest, struct in_str *input)
         return 0;
 }
 
-/* return code is 0 for normal exit, 1 for syntax error */
+/* Return code is 0 for normal exit, 1 for syntax error */
 static int parse_stream(o_string *dest, struct p_context *ctx,
         struct in_str *input, const char *end_trigger)
 {
@@ -3937,7 +3622,7 @@ static void update_charmap(void)
         set_in_charmap(ifs, CHAR_IFS);  /* are ordinary if quoted */
 }
 
-/* most recursion does not come through here, the exception is
+/* Most recursion does not come through here, the exception is
  * from builtin_source() and builtin_eval() */
 static int parse_and_run_stream(struct in_str *inp, int parse_flag)
 {
@@ -3975,7 +3660,9 @@ static int parse_and_run_stream(struct in_str *inp, int parse_flag)
                         free_pipe_list(ctx.list_head, /* indent: */ 0);
                         /* Discard all unprocessed line input, force prompt on */
                         inp->p = NULL;
+#if ENABLE_HUSH_INTERACTIVE
                         inp->promptme = 1;
+#endif
                 }
                 o_free(&temp);
                 /* loop on syntax errors, return on EOF: */
@@ -4034,6 +3721,7 @@ static void setup_job_control(void)
 }
 #endif
 
+
 int hush_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int hush_main(int argc, char **argv)
 {
@@ -4230,3 +3918,318 @@ int lash_main(int argc, char **argv)
         return hush_main(argc, argv);
 }
 #endif
+
+
+/*
+ * Built-ins
+ */
+static int builtin_true(char **argv ATTRIBUTE_UNUSED)
+{
+        return 0;
+}
+
+static int builtin_test(char **argv)
+{
+        int argc = 0;
+        while (*argv) {
+                argc++;
+                argv++;
+        }
+        return test_main(argc, argv - argc);
+}
+
+static int builtin_echo(char **argv)
+{
+        int argc = 0;
+        while (*argv) {
+                argc++;
+                argv++;
+        }
+        return echo_main(argc, argv - argc);
+}
+
+static int builtin_eval(char **argv)
+{
+        int rcode = EXIT_SUCCESS;
+
+        if (argv[1]) {
+                char *str = expand_strvec_to_string(argv + 1);
+                parse_and_run_string(str, PARSEFLAG_EXIT_FROM_LOOP);
+                free(str);
+                rcode = last_return_code;
+        }
+        return rcode;
+}
+
+static int builtin_cd(char **argv)
+{
+        const char *newdir;
+        if (argv[1] == NULL) {
+                // bash does nothing (exitcode 0) if HOME is ""; if it's unset,
+                // bash says "bash: cd: HOME not set" and does nothing (exitcode 1)
+                newdir = getenv("HOME") ? : "/";
+        } else
+                newdir = argv[1];
+        if (chdir(newdir)) {
+                printf("cd: %s: %s\n", newdir, strerror(errno));
+                return EXIT_FAILURE;
+        }
+        set_cwd();
+        return EXIT_SUCCESS;
+}
+
+static int builtin_exec(char **argv)
+{
+        if (argv[1] == NULL)
+                return EXIT_SUCCESS; /* bash does this */
+        {
+#if !BB_MMU
+                char **ptrs2free = alloc_ptrs(argv);
+#endif
+// FIXME: if exec fails, bash does NOT exit! We do...
+                pseudo_exec_argv(ptrs2free, argv + 1);
+                /* never returns */
+        }
+}
+
+static int builtin_exit(char **argv)
+{
+// TODO: bash does it ONLY on top-level sh exit (+interacive only?)
+        //puts("exit"); /* bash does it */
+// TODO: warn if we have background jobs: "There are stopped jobs"
+// On second consecutive 'exit', exit anyway.
+        if (argv[1] == NULL)
+                hush_exit(last_return_code);
+        /* mimic bash: exit 123abc == exit 255 + error msg */
+        xfunc_error_retval = 255;
+        /* bash: exit -2 == exit 254, no error msg */
+        hush_exit(xatoi(argv[1]) & 0xff);
+}
+
+static int builtin_export(char **argv)
+{
+        const char *value;
+        char *name = argv[1];
+
+        if (name == NULL) {
+                // TODO:
+                // ash emits: export VAR='VAL'
+                // bash: declare -x VAR="VAL"
+                // (both also escape as needed (quotes, $, etc))
+                char **e = environ;
+                if (e)
+                        while (*e)
+                                puts(*e++);
+                return EXIT_SUCCESS;
+        }
+
+        value = strchr(name, '=');
+        if (!value) {
+                /* They are exporting something without a =VALUE */
+                struct variable *var;
+
+                var = get_local_var(name);
+                if (var) {
+                        var->flg_export = 1;
+                        putenv(var->varstr);
+                }
+                /* bash does not return an error when trying to export
+                 * an undefined variable.  Do likewise. */
+                return EXIT_SUCCESS;
+        }
+
+        set_local_var(xstrdup(name), 1);
+        return EXIT_SUCCESS;
+}
+
+#if ENABLE_HUSH_JOB
+/* built-in 'fg' and 'bg' handler */
+static int builtin_fg_bg(char **argv)
+{
+        int i, jobnum;
+        struct pipe *pi;
+
+        if (!interactive_fd)
+                return EXIT_FAILURE;
+        /* If they gave us no args, assume they want the last backgrounded task */
+        if (!argv[1]) {
+                for (pi = job_list; pi; pi = pi->next) {
+                        if (pi->jobid == last_jobid) {
+                                goto found;
+                        }
+                }
+                bb_error_msg("%s: no current job", argv[0]);
+                return EXIT_FAILURE;
+        }
+        if (sscanf(argv[1], "%%%d", &jobnum) != 1) {
+                bb_error_msg("%s: bad argument '%s'", argv[0], argv[1]);
+                return EXIT_FAILURE;
+        }
+        for (pi = job_list; pi; pi = pi->next) {
+                if (pi->jobid == jobnum) {
+                        goto found;
+                }
+        }
+        bb_error_msg("%s: %d: no such job", argv[0], jobnum);
+        return EXIT_FAILURE;
+ found:
+        // TODO: bash prints a string representation
+        // of job being foregrounded (like "sleep 1 | cat")
+        if (*argv[0] == 'f') {
+                /* Put the job into the foreground.  */
+                tcsetpgrp(interactive_fd, pi->pgrp);
+        }
+
+        /* Restart the processes in the job */
+        debug_printf_jobs("reviving %d procs, pgrp %d\n", pi->num_progs, pi->pgrp);
+        for (i = 0; i < pi->num_progs; i++) {
+                debug_printf_jobs("reviving pid %d\n", pi->progs[i].pid);
+                pi->progs[i].is_stopped = 0;
+        }
+        pi->stopped_progs = 0;
+
+        i = kill(- pi->pgrp, SIGCONT);
+        if (i < 0) {
+                if (errno == ESRCH) {
+                        delete_finished_bg_job(pi);
+                        return EXIT_SUCCESS;
+                } else {
+                        bb_perror_msg("kill (SIGCONT)");
+                }
+        }
+
+        if (*argv[0] == 'f') {
+                remove_bg_job(pi);
+                return checkjobs_and_fg_shell(pi);
+        }
+        return EXIT_SUCCESS;
+}
+#endif
+
+#if ENABLE_HUSH_HELP
+static int builtin_help(char **argv ATTRIBUTE_UNUSED)
+{
+        const struct built_in_command *x;
+
+        printf("\nBuilt-in commands:\n");
+        printf("-------------------\n");
+        for (x = bltins; x != &bltins[ARRAY_SIZE(bltins)]; x++) {
+                printf("%s\t%s\n", x->cmd, x->descr);
+        }
+        printf("\n\n");
+        return EXIT_SUCCESS;
+}
+#endif
+
+#if ENABLE_HUSH_JOB
+static int builtin_jobs(char **argv ATTRIBUTE_UNUSED)
+{
+        struct pipe *job;
+        const char *status_string;
+
+        for (job = job_list; job; job = job->next) {
+                if (job->running_progs == job->stopped_progs)
+                        status_string = "Stopped";
+                else
+                        status_string = "Running";
+
+                printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->cmdtext);
+        }
+        return EXIT_SUCCESS;
+}
+#endif
+
+static int builtin_pwd(char **argv ATTRIBUTE_UNUSED)
+{
+        puts(set_cwd());
+        return EXIT_SUCCESS;
+}
+
+static int builtin_read(char **argv)
+{
+        char *string;
+        const char *name = argv[1] ? argv[1] : "REPLY";
+
+        string = xmalloc_reads(STDIN_FILENO, xasprintf("%s=", name), NULL);
+        return set_local_var(string, 0);
+}
+
+/* built-in 'set [VAR=value]' handler */
+static int builtin_set(char **argv)
+{
+        char *temp = argv[1];
+        struct variable *e;
+
+        if (temp == NULL)
+                for (e = top_var; e; e = e->next)
+                        puts(e->varstr);
+        else
+                set_local_var(xstrdup(temp), 0);
+
+        return EXIT_SUCCESS;
+}
+
+static int builtin_shift(char **argv)
+{
+        int n = 1;
+        if (argv[1]) {
+                n = atoi(argv[1]);
+        }
+        if (n >= 0 && n < global_argc) {
+                global_argv[n] = global_argv[0];
+                global_argc -= n;
+                global_argv += n;
+                return EXIT_SUCCESS;
+        }
+        return EXIT_FAILURE;
+}
+
+static int builtin_source(char **argv)
+{
+        FILE *input;
+        int status;
+
+        if (argv[1] == NULL)
+                return EXIT_FAILURE;
+
+        /* XXX search through $PATH is missing */
+        input = fopen(argv[1], "r");
+        if (!input) {
+                bb_error_msg("cannot open '%s'", argv[1]);
+                return EXIT_FAILURE;
+        }
+        close_on_exec_on(fileno(input));
+
+        /* Now run the file */
+        /* XXX argv and argc are broken; need to save old global_argv
+         * (pointer only is OK!) on this stack frame,
+         * set global_argv=argv+1, recurse, and restore. */
+        status = parse_and_run_file(input);
+        fclose(input);
+        return status;
+}
+
+static int builtin_umask(char **argv)
+{
+        mode_t new_umask;
+        const char *arg = argv[1];
+        char *end;
+        if (arg) {
+                new_umask = strtoul(arg, &end, 8);
+                if (*end != '\0' || end == arg) {
+                        return EXIT_FAILURE;
+                }
+        } else {
+                new_umask = umask(0);
+                printf("%.3o\n", (unsigned) new_umask);
+        }
+        umask(new_umask);
+        return EXIT_SUCCESS;
+}
+
+static int builtin_unset(char **argv)
+{
+        /* bash always returns true */
+        unset_local_var(argv[1]);
+        return EXIT_SUCCESS;
+}
diff --git a/shell/hush_leaktool.sh b/shell/hush_leaktool.sh
index 54a19aa6f..54161b3e9 100644
--- a/shell/hush_leaktool.sh
+++ b/shell/hush_leaktool.sh
@@ -8,6 +8,6 @@ freelist=`grep 'free 0x' "$output" | cut -d' ' -f2 | sort | uniq | xargs`
 grep -v free "$output" >temp1
 for freed in $freelist; do
     echo Dropping $freed
-    cat temp1 | grep -v $freed >temp2
+    grep -v $freed <temp1 >temp2
     mv temp2 temp1
 done