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
diff --git a/shell/hush.c b/shell/hush.c
index 543f1fe..d791b62 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -513,6 +513,7 @@
smallint flag_break_continue;
#endif
smallint fake_mode;
+ smallint exiting; /* used to prevent EXIT trap recursion */
/* These four support $?, $#, and $1 */
smalluint last_exitcode;
/* are global_argv and global_argv[1..n] malloced? (note: not [0]) */
@@ -851,7 +852,7 @@
*
* Trap handlers will execute even within trap handlers. (right?)
*
- * User trap handlers are forgotten when subshell ("(cmd)") is entered. [TODO]
+ * User trap handlers are forgotten when subshell ("(cmd)") is entered.
*
* If job control is off, backgrounded commands ("cmd &")
* have SIGINT, SIGQUIT set to SIG_IGN.
@@ -905,7 +906,7 @@
* set bit in blocked_set (even if 'cmd' is '')
* after [v]fork, if we plan to be a shell:
* nothing for {} child shell (say, "true | { true; true; } | true")
- * unset all traps if () shell. [TODO]
+ * unset all traps if () shell.
* after [v]fork, if we plan to exec:
* POSIX says pending signal mask is cleared in child - no need to clear it.
* Restore blocked signal set to one inherited by shell just prior to exec.
@@ -1005,9 +1006,13 @@
static void hush_exit(int exitcode) NORETURN;
static void hush_exit(int exitcode)
{
- if (G.traps && G.traps[0] && G.traps[0][0]) {
- char *argv[] = { NULL, xstrdup(G.traps[0]), NULL };
-//TODO: do we need to prevent recursion?
+ if (G.exiting <= 0 && G.traps && G.traps[0] && G.traps[0][0]) {
+ /* Prevent recursion:
+ * trap "echo Hi; exit" EXIT; exit
+ */
+ char *argv[] = { NULL, G.traps[0], NULL };
+ G.traps[0] = NULL;
+ G.exiting = 1;
builtin_eval(argv);
free(argv[1]);
}
@@ -2350,7 +2355,6 @@
* and stderr if they are redirected. */
static int setup_redirects(struct command *prog, int squirrel[])
{
-//TODO: no callers ever check return value - ?!
int openfd, mode;
struct redir_struct *redir;
@@ -2952,11 +2956,13 @@
#endif
/* { list } */
debug_printf("non-subshell group\n");
- setup_redirects(command, squirrel);
- debug_printf_exec(": run_list\n");
- rcode = run_list(command->group) & 0xff;
+ rcode = 1; /* exitcode if redir failed */
+ if (setup_redirects(command, squirrel) == 0) {
+ debug_printf_exec(": run_list\n");
+ rcode = run_list(command->group) & 0xff;
+ debug_printf_exec("run_pipe return %d\n", rcode);
+ }
restore_redirects(squirrel);
- debug_printf_exec("run_pipe return %d\n", rcode);
IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;)
return rcode;
}
@@ -2970,7 +2976,7 @@
if (argv[command->assignment_cnt] == NULL) {
/* Assignments, but no command */
/* Ensure redirects take effect. Try "a=t >file" */
- setup_redirects(command, squirrel);
+ rcode = setup_redirects(command, squirrel);
restore_redirects(squirrel);
/* Set shell variables */
while (*argv) {
@@ -2983,7 +2989,8 @@
/* Do we need to flag set_local_var() errors?
* "assignment to readonly var" and "putenv error"
*/
- return EXIT_SUCCESS;
+ IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;)
+ return rcode;
}
/* Expand the rest into (possibly) many strings each */
@@ -2994,8 +3001,7 @@
continue;
if (x->function == builtin_exec && argv_expanded[1] == NULL) {
debug_printf("exec with redirects only\n");
- setup_redirects(command, NULL);
- rcode = EXIT_SUCCESS;
+ rcode = setup_redirects(command, NULL);
goto clean_up_and_ret1;
}
debug_printf("builtin inline %s\n", argv_expanded[0]);
@@ -3003,12 +3009,14 @@
* This is perfect for work that comes after exec().
* Is it really safe for inline use? Experimentally,
* things seem to work with glibc. */
- setup_redirects(command, squirrel);
- new_env = expand_assignments(argv, command->assignment_cnt);
- old_env = putenv_all_and_save_old(new_env);
- debug_printf_exec(": builtin '%s' '%s'...\n",
- x->cmd, argv_expanded[1]);
- rcode = x->function(argv_expanded) & 0xff;
+ rcode = setup_redirects(command, squirrel);
+ if (rcode == 0) {
+ new_env = expand_assignments(argv, command->assignment_cnt);
+ old_env = putenv_all_and_save_old(new_env);
+ debug_printf_exec(": builtin '%s' '%s'...\n",
+ x->cmd, argv_expanded[1]);
+ rcode = x->function(argv_expanded) & 0xff;
+ }
#if ENABLE_FEATURE_SH_STANDALONE
clean_up_and_ret:
#endif
@@ -3027,13 +3035,15 @@
#if ENABLE_FEATURE_SH_STANDALONE
i = find_applet_by_name(argv_expanded[0]);
if (i >= 0 && APPLET_IS_NOFORK(i)) {
- setup_redirects(command, squirrel);
- save_nofork_data(&G.nofork_save);
- new_env = expand_assignments(argv, command->assignment_cnt);
- old_env = putenv_all_and_save_old(new_env);
- debug_printf_exec(": run_nofork_applet '%s' '%s'...\n",
+ rcode = setup_redirects(command, squirrel);
+ if (rcode == 0) {
+ save_nofork_data(&G.nofork_save);
+ new_env = expand_assignments(argv, command->assignment_cnt);
+ old_env = putenv_all_and_save_old(new_env);
+ debug_printf_exec(": run_nofork_applet '%s' '%s'...\n",
argv_expanded[0], argv_expanded[1]);
- rcode = run_nofork_applet_prime(&G.nofork_save, i, argv_expanded);
+ rcode = run_nofork_applet_prime(&G.nofork_save, i, argv_expanded);
+ }
goto clean_up_and_ret;
}
#endif
@@ -3095,7 +3105,8 @@
close(pipefds[0]); /* read end */
/* Like bash, explicit redirects override pipes,
* and the pipe fd is available for dup'ing. */
- setup_redirects(command, NULL);
+ if (setup_redirects(command, NULL))
+ _exit(1);
/* Restore default handlers just prior to exec */
/*signal(SIGCHLD, SIG_DFL); - so far we don't have any handlers */
@@ -3324,9 +3335,9 @@
//// /* ctrl-Z handler will store pid etc in pi */
//// G.toplevel_list = pi;
//// G.ctrl_z_flag = 0;
-////#if ENABLE_FEATURE_SH_STANDALONE
-//// G.nofork_save.saved = 0; /* in case we will run a nofork later */
-////#endif
+#if ENABLE_FEATURE_SH_STANDALONE
+ G.nofork_save.saved = 0; /* in case we will run a nofork later */
+#endif
//// signal_SA_RESTART_empty_mask(SIGTSTP, handler_ctrl_z);
//// signal(SIGINT, handler_ctrl_c);
}
@@ -5680,6 +5691,8 @@
enable_restore_tty_pgrp_on_exit(); /* sets die_sleep = -1 */
if (setjmp(die_jmp)) {
/* xfunc has failed! die die die */
+ /* no EXIT traps, this is an escape hatch! */
+ G.exiting = 1;
hush_exit(xfunc_error_retval);
}
} else if (!signal_mask_is_inited) {
@@ -5907,6 +5920,9 @@
//puts("exit"); /* bash does it */
// TODO: warn if we have background jobs: "There are stopped jobs"
// On second consecutive 'exit', exit anyway.
+// perhaps use G.exiting = -1 as indicator "last cmd was exit"
+
+ /* note: EXIT trap is run by hush_exit */
if (*++argv == NULL)
hush_exit(G.last_exitcode);
/* mimic bash: exit 123abc == exit 255 + error msg */
diff --git a/shell/hush_test/hush-misc/exit1.right b/shell/hush_test/hush-misc/exit1.right
new file mode 100644
index 0000000..dd2cfc2
--- /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 0000000..41e0d09
--- /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 0000000..3d20bbf
--- /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 0000000..7c28e43
--- /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