ash: fix signal and "set -e" interaction

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

5 files changed, 58 insertions, 6 deletions

diff --git a/shell/ash.c b/shell/ash.c
index 9089adc63..ea835527e 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -8214,7 +8214,7 @@ static int evalstring(char *s, int mask);
 
 /* Called to execute a trap.
  * Single callsite - at the end of evaltree().
- * If we return non-zero, exaltree raises EXEXIT exception.
+ * If we return non-zero, evaltree raises EXEXIT exception.
  *
  * Perhaps we should avoid entering new trap handlers
  * while we are executing a trap handler. [is it a TODO?]
@@ -8404,11 +8404,15 @@ evaltree(union node *n, int flags)
 
  out:
         exception_handler = savehandler;
+
  out1:
+        /* Order of checks below is important:
+         * signal handlers trigger before exit caused by "set -e".
+         */
+        if (pending_sig && dotrap())
+                goto exexit;
         if (checkexit & exitstatus)
                 evalskip |= SKIPEVAL;
-        else if (pending_sig && dotrap())
-                goto exexit;
 
         if (flags & EV_EXIT) {
  exexit:
@@ -8740,7 +8744,7 @@ poplocalvars(void)
         while ((lvp = localvars) != NULL) {
                 localvars = lvp->next;
                 vp = lvp->vp;
-                TRACE(("poplocalvar %s\n", vp ? vp->text : "-"));
+                TRACE(("poplocalvar %s\n", vp ? vp->var_text : "-"));
                 if (vp == NULL) {       /* $- saved */
                         memcpy(optlist, lvp->text, sizeof(optlist));
                         free((char*)lvp->text);
@@ -13009,10 +13013,12 @@ int ash_main(int argc UNUSED_PARAM, char **argv)
                 if (e == EXERROR)
                         exitstatus = 2;
                 s = state;
-                if (e == EXEXIT || s == 0 || iflag == 0 || shlvl)
+                if (e == EXEXIT || s == 0 || iflag == 0 || shlvl) {
                         exitshell();
-                if (e == EXINT)
+                }
+                if (e == EXINT) {
                         outcslow('\n', stderr);
+                }
 
                 popstackmark(&smark);
                 FORCE_INT_ON; /* enable interrupts */
@@ -13105,6 +13111,7 @@ int ash_main(int argc UNUSED_PARAM, char **argv)
                 _mcleanup();
         }
 #endif
+        TRACE(("End of main reached\n"));
         exitshell();
         /* NOTREACHED */
 }
diff --git a/shell/ash_test/ash-signals/signal8.right b/shell/ash_test/ash-signals/signal8.right
new file mode 100644
index 000000000..39572f30e
--- /dev/null
+++ b/shell/ash_test/ash-signals/signal8.right
@@ -0,0 +1,3 @@
+Removing traps
+End of exit_func
+Done: 0
diff --git a/shell/ash_test/ash-signals/signal8.tests b/shell/ash_test/ash-signals/signal8.tests
new file mode 100755
index 000000000..731af7477
--- /dev/null
+++ b/shell/ash_test/ash-signals/signal8.tests
@@ -0,0 +1,18 @@
+"$THIS_SH" -c '
+exit_func() {
+    echo "Removing traps"
+    trap - EXIT TERM INT
+    echo "End of exit_func"
+}
+set -e
+trap exit_func EXIT TERM INT
+sleep 2
+exit 77
+' &
+
+sleep 1
+# BUG: ash kills -PGRP, but in non-interactive shell we do not create pgrps!
+# In this case, bash kills by PID, not PGRP.
+kill -TERM %1
+wait
+echo Done: $?
diff --git a/shell/ash_test/ash-signals/signal9.right b/shell/ash_test/ash-signals/signal9.right
new file mode 100644
index 000000000..39572f30e
--- /dev/null
+++ b/shell/ash_test/ash-signals/signal9.right
@@ -0,0 +1,3 @@
+Removing traps
+End of exit_func
+Done: 0
diff --git a/shell/ash_test/ash-signals/signal9.tests b/shell/ash_test/ash-signals/signal9.tests
new file mode 100755
index 000000000..18e71012b
--- /dev/null
+++ b/shell/ash_test/ash-signals/signal9.tests
@@ -0,0 +1,21 @@
+# Note: the inner script is a test which checks for a different bug
+# (ordering between INT handler and exit on "set -e"),
+# but so far I did not figure out how to simulate it non-interactively.
+
+"$THIS_SH" -c '
+exit_func() {
+    echo "Removing traps"
+    trap - EXIT TERM INT
+    echo "End of exit_func"
+}
+set -e
+trap exit_func EXIT TERM INT
+sleep 2
+exit 77
+' &
+
+child=$!
+sleep 1
+kill -TERM $child
+wait
+echo Done: $?