hush: fix EXIT trap recursion case; check redirection failures

function                                             old     new   delta                          
run_pipe                                            1299    1328     +29                          
hush_exit                                             90     102     +12                          
hush_main                                           1172    1179      +7                          
run_list                                            1226    1225      -1                          
------------------------------------------------------------------------------                    
(add/remove: 0/0 grow/shrink: 3/1 up/down: 48/-1)              Total: 47 bytes 

4 files changed, 28 insertions, 0 deletions

diff --git a/shell/hush_test/hush-misc/exit1.right b/shell/hush_test/hush-misc/exit1.right
new file mode 100644
index 000000000..dd2cfc279
--- /dev/null
+++ b/shell/hush_test/hush-misc/exit1.right
@@ -0,0 +1 @@
+Once
diff --git a/shell/hush_test/hush-misc/exit1.tests b/shell/hush_test/hush-misc/exit1.tests
new file mode 100755
index 000000000..41e0d092d
--- /dev/null
+++ b/shell/hush_test/hush-misc/exit1.tests
@@ -0,0 +1,4 @@
+trap "echo Not shown" EXIT
+(exit)  # must be silent
+trap "echo Once; exit" EXIT
+{ exit; }
diff --git a/shell/hush_test/hush-misc/redir3.right b/shell/hush_test/hush-misc/redir3.right
new file mode 100644
index 000000000..3d20bbf68
--- /dev/null
+++ b/shell/hush_test/hush-misc/redir3.right
@@ -0,0 +1,14 @@
+hush: can't open '/does/not/exist': No such file or directory
+One:1
+hush: can't open '/cant/be/created': No such file or directory
+One:1
+Ok
+hush: can't open '/cant/be/created': No such file or directory
+Zero:0
+hush: can't open '/cant/be/created': No such file or directory
+One:1
+hush: can't open '/cant/be/created': No such file or directory
+One:1
+hush: can't open '/cant/be/created': No such file or directory
+Zero:0
+Done
diff --git a/shell/hush_test/hush-misc/redir3.tests b/shell/hush_test/hush-misc/redir3.tests
new file mode 100755
index 000000000..7c28e4324
--- /dev/null
+++ b/shell/hush_test/hush-misc/redir3.tests
@@ -0,0 +1,9 @@
+echo Error >/does/not/exist; echo One:$?
+t=BAD
+t=Ok >>/cant/be/created; echo One:$?
+echo $t
+! >/cant/be/created; echo Zero:$?
+exec >/cant/be/created; echo One:$?
+exec /bin/true >/cant/be/created; echo One:$?
+! exec /bin/true >/cant/be/created; echo Zero:$?
+echo Done