hush: add readonly testcase, fix fallout

function                                             old     new   delta
helper_export_local                                  185     214     +29
run_pipe                                            1549    1560     +11
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 40/0)               Total: 40 bytes

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

3 files changed, 53 insertions, 9 deletions

diff --git a/shell/hush.c b/shell/hush.c
index 7771172b6..eab1284f6 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -7767,10 +7767,10 @@ static NOINLINE int run_pipe(struct pipe *pi)
                         if (new_env) {
                                 argv = new_env;
                                 while (*argv) {
-                                        set_local_var(*argv, /*flag:*/ 0);
-                                        /* Do we need to flag set_local_var() errors?
-                                         * "assignment to readonly var" and "putenv error"
-                                         */
+                                        if (set_local_var(*argv, /*flag:*/ 0)) {
+                                                /* assignment to readonly var / putenv error? */
+                                                rcode = 1;
+                                        }
                                         argv++;
                                 }
                         }
@@ -7795,10 +7795,10 @@ static NOINLINE int run_pipe(struct pipe *pi)
                                         fprintf(stderr, " %s", p);
                                 debug_printf_exec("set shell var:'%s'->'%s'\n",
                                                 *argv, p);
-                                set_local_var(p, /*flag:*/ 0);
-                                /* Do we need to flag set_local_var() errors?
-                                 * "assignment to readonly var" and "putenv error"
-                                 */
+                                if (set_local_var(p, /*flag:*/ 0)) {
+                                        /* assignment to readonly var / putenv error? */
+                                        rcode = 1;
+                                }
                                 argv++;
                         }
                         if (G_x_mode)
@@ -9336,6 +9336,13 @@ static int helper_export_local(char **argv, unsigned flags)
                                         continue;
                                 }
                         }
+                        if (flags & SETFLAG_MAKE_RO) {
+                                /* readonly NAME (without =VALUE) */
+                                if (var) {
+                                        var->flg_read_only = 1;
+                                        continue;
+                                }
+                        }
 # if ENABLE_HUSH_LOCAL
                         /* Is this "local" bltin? */
                         if (!(flags & (SETFLAG_EXPORT|SETFLAG_UNEXPORT|SETFLAG_MAKE_RO))) {
@@ -9364,7 +9371,8 @@ static int helper_export_local(char **argv, unsigned flags)
                         /* (Un)exporting/making local NAME=VALUE */
                         name = xstrdup(name);
                 }
-                set_local_var(name, flags);
+                if (set_local_var(name, flags))
+                        return EXIT_FAILURE;
         } while (*++argv);
         return EXIT_SUCCESS;
 }
diff --git a/shell/hush_test/hush-vars/readonly0.right b/shell/hush_test/hush-vars/readonly0.right
new file mode 100644
index 000000000..9688d2e5f
--- /dev/null
+++ b/shell/hush_test/hush-vars/readonly0.right
@@ -0,0 +1,12 @@
+readonly a=A
+readonly b=B
+Ok:0
+hush: a=A: readonly variable
+Fail:1
+hush: a=A: readonly variable
+Fail:1
+hush: a=A: readonly variable
+Fail:1
+Visible:0
+hush: a: readonly variable
+Fail:1
diff --git a/shell/hush_test/hush-vars/readonly0.tests b/shell/hush_test/hush-vars/readonly0.tests
new file mode 100755
index 000000000..3845f76ac
--- /dev/null
+++ b/shell/hush_test/hush-vars/readonly0.tests
@@ -0,0 +1,24 @@
+readonly a=A
+b=B
+readonly b
+# readonly on already readonly var is harmless
+readonly b a
+readonly | grep '^readonly [ab]='
+# this should work
+export a b
+export -n a b
+echo Ok:$?
+env | grep -e^a= -e^b=  # shows nothing
+
+# these should all fail (despite the same value being assigned)
+# bash does not abort even in non-interactive more (in script)
+true
+a=A
+echo Fail:$?; true
+readonly a=A
+echo Fail:$?; true
+export a=A
+echo Fail:$?; true
+a=A echo Visible:$? # command still runs
+unset a
+echo Fail:$?; true