hush: make run_pipe code simpler to understand, no logic changes

function                                             old     new   delta
run_pipe                                            1641    1651     +10

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 57 insertions, 66 deletions

diff --git a/shell/hush.c b/shell/hush.c
index 00d86b4e4..3ad6a9724 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -7599,9 +7599,8 @@ static NOINLINE void pseudo_exec_argv(nommu_save_t *nommu_save,
 {
         const struct built_in_command *x;
         char **new_env;
-#if ENABLE_HUSH_COMMAND
-        char opt_vV = 0;
-#endif
+        IF_HUSH_COMMAND(char opt_vV = 0;)
+        IF_HUSH_FUNCTIONS(const struct function *funcp;)
 
         new_env = expand_assignments(argv, assignment_cnt);
         dump_cmd_in_x_mode(new_env);
@@ -7640,12 +7639,9 @@ static NOINLINE void pseudo_exec_argv(nommu_save_t *nommu_save,
 
 #if ENABLE_HUSH_FUNCTIONS
         /* Check if the command matches any functions (this goes before bltins) */
-        {
-                const struct function *funcp = find_function(argv[0]);
-                if (funcp) {
-                        exec_function(&nommu_save->argv_from_re_execing, funcp, argv);
-                }
-        }
+        funcp = find_function(argv[0]);
+        if (funcp)
+                exec_function(&nommu_save->argv_from_re_execing, funcp, argv);
 #endif
 
 #if ENABLE_HUSH_COMMAND
@@ -8366,22 +8362,18 @@ static NOINLINE int run_pipe(struct pipe *pi)
                 if (!funcp)
                         x = find_builtin(argv_expanded[0]);
                 if (x || funcp) {
-                        if (!funcp) {
-                                if (x->b_function == builtin_exec && argv_expanded[1] == NULL) {
-                                        debug_printf("exec with redirects only\n");
-                                        rcode = setup_redirects(command, NULL);
-                                        /* rcode=1 can be if redir file can't be opened */
-                                        goto clean_up_and_ret1;
-                                }
+                        if (x && x->b_function == builtin_exec && argv_expanded[1] == NULL) {
+                                debug_printf("exec with redirects only\n");
+                                rcode = setup_redirects(command, NULL);
+                                /* rcode=1 can be if redir file can't be opened */
+                                goto clean_up_and_ret1;
                         }
 
-                        /* Without bumping var nesting level, this leaks
-                         * exported $a:
+                        /* Bump var nesting, or this will leak exported $a:
                          * a=b true; env | grep ^a=
                          */
                         enter_var_nest_level();
                         rcode = redirect_and_varexp_helper(&old_vars, command, &squirrel, argv_expanded);
-
                         if (rcode == 0) {
                                 if (!funcp) {
                                         debug_printf_exec(": builtin '%s' '%s'...\n",
@@ -8406,58 +8398,57 @@ static NOINLINE int run_pipe(struct pipe *pi)
                                 }
 #endif
                         }
- clean_up_and_ret:
-                        leave_var_nest_level();
-                        add_vars(old_vars);
-                        restore_redirects(squirrel);
-                        /*
-                         * Try "usleep 99999999" + ^C + "echo $?"
-                         * with FEATURE_SH_NOFORK=y.
-                         */
-                        if (!funcp) {
-                                /* It was builtin or nofork.
-                                 * if this would be a real fork/execed program,
-                                 * it should have died if a fatal sig was received.
-                                 * But OTOH, there was no separate process,
-                                 * the sig was sent to _shell_, not to non-existing
-                                 * child.
-                                 * Let's just handle ^C only, this one is obvious:
-                                 * we aren't ok with exitcode 0 when ^C was pressed
-                                 * during builtin/nofork.
+                } else
+                if (ENABLE_FEATURE_SH_NOFORK && NUM_APPLETS > 1) {
+                        int n = find_applet_by_name(argv_expanded[0]);
+                        if (n < 0 || !APPLET_IS_NOFORK(n))
+                                goto must_fork;
+
+                        enter_var_nest_level();
+                        rcode = redirect_and_varexp_helper(&old_vars, command, &squirrel, argv_expanded);
+                        if (rcode == 0) {
+                                debug_printf_exec(": run_nofork_applet '%s' '%s'...\n",
+                                        argv_expanded[0], argv_expanded[1]);
+                                /*
+                                 * Note: signals (^C) can't interrupt here.
+                                 * We remember them and they will be acted upon
+                                 * after applet returns.
+                                 * This makes applets which can run for a long time
+                                 * and/or wait for user input ineligible for NOFORK:
+                                 * for example, "yes" or "rm" (rm -i waits for input).
                                  */
-                                if (sigismember(&G.pending_set, SIGINT))
-                                        rcode = 128 + SIGINT;
+                                rcode = run_nofork_applet(n, argv_expanded);
                         }
- clean_up_and_ret1:
-                        free(argv_expanded);
-                        IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;)
-                        debug_leave();
-                        debug_printf_exec("run_pipe return %d\n", rcode);
-                        return rcode;
                 }
 
-                if (ENABLE_FEATURE_SH_NOFORK && NUM_APPLETS > 1) {
-                        int n = find_applet_by_name(argv_expanded[0]);
-                        if (n >= 0 && APPLET_IS_NOFORK(n)) {
-                                enter_var_nest_level();
-                                rcode = redirect_and_varexp_helper(&old_vars, command, &squirrel, argv_expanded);
-                                if (rcode == 0) {
-                                        debug_printf_exec(": run_nofork_applet '%s' '%s'...\n",
-                                                argv_expanded[0], argv_expanded[1]);
-                                        /*
-                                         * Note: signals (^C) can't interrupt here.
-                                         * We remember them and they will be acted upon
-                                         * after applet returns.
-                                         * This makes applets which can run for a long time
-                                         * and/or wait for user input ineligible for NOFORK:
-                                         * for example, "yes" or "rm" (rm -i waits for input).
-                                         */
-                                        rcode = run_nofork_applet(n, argv_expanded);
-                                }
-                                goto clean_up_and_ret;
-                        }
+                leave_var_nest_level();
+                add_vars(old_vars);
+                restore_redirects(squirrel);
+
+                /*
+                 * Try "usleep 99999999" + ^C + "echo $?"
+                 * with FEATURE_SH_NOFORK=y.
+                 */
+                if (!funcp) {
+                        /* It was builtin or nofork.
+                         * if this would be a real fork/execed program,
+                         * it should have died if a fatal sig was received.
+                         * But OTOH, there was no separate process,
+                         * the sig was sent to _shell_, not to non-existing
+                         * child.
+                         * Let's just handle ^C only, this one is obvious:
+                         * we aren't ok with exitcode 0 when ^C was pressed
+                         * during builtin/nofork.
+                         */
+                        if (sigismember(&G.pending_set, SIGINT))
+                                rcode = 128 + SIGINT;
                 }
-                /* It is neither builtin nor applet. We must fork. */
+ clean_up_and_ret1:
+                free(argv_expanded);
+                IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;)
+                debug_leave();
+                debug_printf_exec("run_pipe return %d\n", rcode);
+                return rcode;
         }
 
  must_fork: