hush: fix var=`exit 2` not setting $? to 2

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

diff --git a/shell/hush.c b/shell/hush.c
index df81eaa..8da9439 100644 (file)
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -2523,7 +2523,7 @@ static NOINLINE int expand_vars_to_list(o_string *output, int n, char *arg, char
                         * and $IFS-splitted */
                        debug_printf_subst("SUBST '%s' first_ch %x\n", arg, first_ch);
                        G.last_exitcode = process_command_subs(&subst_result, arg);
-                       debug_printf_subst("SUBST RES '%s'\n", subst_result.data);
+                       debug_printf_subst("SUBST RES:%d '%s'\n", G.last_exitcode, subst_result.data);
                        val = subst_result.data;
                        goto store_val;
 #endif
@@ -4117,9 +4117,9 @@ static NOINLINE int run_pipe(struct pipe *pi)
 
                if (argv[command->assignment_cnt] == NULL) {
                        /* Assignments, but no command */
-                       /* Ensure redirects take effect. Try "a=t >file" */
+                       /* Ensure redirects take effect (that is, create files).
+                        * Try "a=t >file": */
                        rcode = setup_redirects(command, squirrel);
-//FIXME: "false; q=`false`; echo $?" should print 1
                        restore_redirects(squirrel);
                        /* Set shell variables */
                        while (*argv) {
@@ -4129,6 +4129,11 @@ static NOINLINE int run_pipe(struct pipe *pi)
                                set_local_var(p, /*exp:*/ 0, /*lvl:*/ 0, /*ro:*/ 0);
                                argv++;
                        }
+                       /* Redirect error sets $? to 1. Othervise,
+                        * if evaluating assignment value set $?, retain it.
+                        * Try "false; q=`exit 2`; echo $?" - should print 2: */
+                       if (rcode == 0)
+                               rcode = G.last_exitcode;
                        /* Do we need to flag set_local_var() errors?
                         * "assignment to readonly var" and "putenv error"
                         */
@@ -4186,7 +4191,7 @@ static NOINLINE int run_pipe(struct pipe *pi)
                                old_vars = set_vars_and_save_old(new_env);
                                if (!funcp) {
                                        debug_printf_exec(": builtin '%s' '%s'...\n",
-                                               x->cmd, argv_expanded[1]);
+                                               x->b_cmd, argv_expanded[1]);
                                        rcode = x->b_function(argv_expanded) & 0xff;
                                        fflush_all();
                                }
@@ -6814,7 +6819,7 @@ int hush_main(int argc, char **argv)
        struct variable *cur_var;
 
        INIT_G();
-       if (EXIT_SUCCESS) /* if EXIT_SUCCESS == 0, is already done */
+       if (EXIT_SUCCESS) /* if EXIT_SUCCESS == 0, it is already done */
                G.last_exitcode = EXIT_SUCCESS;
 #if !BB_MMU
        G.argv0_for_re_execing = argv[0];

diff --git a/shell/hush_test/hush-psubst/falsetick.right b/shell/hush_test/hush-psubst/falsetick.right
new file mode 100644 (file)
index 0000000..0b98fb7
--- /dev/null
+++ b/shell/hush_test/hush-psubst/falsetick.right
@@ -0,0 +1,27 @@
+0
+0
+0
+0
+2
+2
+2
+2
+hush: can't open '/does/not/exist': No such file or directory
+1
+hush: can't open '/does/not/exist': No such file or directory
+1
+hush: can't open '/does/not/exist': No such file or directory
+1
+hush: can't open '/does/not/exist': No such file or directory
+1
+hush: can't open '/does/not/exist': No such file or directory
+1
+hush: can't open '/does/not/exist': No such file or directory
+1
+hush: can't open '/does/not/exist': No such file or directory
+1
+hush: can't open '/does/not/exist': No such file or directory
+1
+hush: can't open '/does/not/exist': No such file or directory
+1
+Done: a=b

diff --git a/shell/hush_test/hush-psubst/falsetick.tests b/shell/hush_test/hush-psubst/falsetick.tests
new file mode 100755 (executable)
index 0000000..44d2eae
--- /dev/null
+++ b/shell/hush_test/hush-psubst/falsetick.tests
@@ -0,0 +1,22 @@
+# Exitcode 0 (`` has no exitcode, but assignment has):
+true;  a=``; echo $?
+false; a=``; echo $?
+true;  a=$(); echo $?
+false; a=$(); echo $?
+# Exitcode 2 (`cmd` expansion sets exitcode after assignment set it to 0):
+true;  a=`exit 2`; echo $?
+false; a=`exit 2`; echo $?
+true;  a=$(exit 2); echo $?
+false; a=$(exit 2); echo $?
+# Exitcode 1 (redirect sets exitcode to 1 on error after them):
+true;  a=`` >/does/not/exist; echo $?
+false; a=`` >/does/not/exist; echo $?
+true;  a=$() >/does/not/exist; echo $?
+false; a=$() >/does/not/exist; echo $?
+true;  a=`exit 2` >/does/not/exist; echo $?
+false; a=`exit 2` >/does/not/exist; echo $?
+true;  a=$(exit 2) >/does/not/exist; echo $?
+false; a=$(exit 2) >/does/not/exist; echo $?
+# ...and assignment still happens despite redirect error:
+true;  a=$(echo b) >/does/not/exist; echo $?
+echo "Done: a=$a"