40576 (tweaked): entersubsh(): unblock any signals that were blocked for trap handling

Also small improvement to loop that resets trap handlers

2 files changed, 20 insertions, 3 deletions

diff --git a/ChangeLog b/ChangeLog
index 5f145a5a4..df1097493 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2017-02-19  Barton E. Schaefer  <schaefer@zsh.org>
+
+	* 40576 (tweaked): Src/exec.c: entersubsh(): small improvement to
+	loop that resets trap handlers; unblock any signals that were
+	blocked for trap handling
+
 2017-02-19  Oliver Kiddle  <opk@zsh.org>
 
 	* 40569: Completion/Unix/Command/_gphoto2: update to gphoto2 2.5.11
diff --git a/Src/exec.c b/Src/exec.c
index 8f4969f52..83d1513d0 100644
--- a/Src/exec.c
+++ b/Src/exec.c
@@ -975,9 +975,8 @@ entersubsh(int flags)
     int sig, monitor, job_control_ok;
 
     if (!(flags & ESUB_KEEPTRAP))
-	for (sig = 0; sig < VSIGCOUNT; sig++)
-	    if (!(sigtrapped[sig] & ZSIG_FUNC) &&
-		sig != SIGDEBUG && sig != SIGZERR)
+	for (sig = 0; sig < SIGCOUNT; sig++)
+	    if (!(sigtrapped[sig] & ZSIG_FUNC))
 		unsettrap(sig);
     monitor = isset(MONITOR);
     job_control_ok = monitor && (flags & ESUB_JOB_CONTROL) && isset(POSIXJOBS);
@@ -1068,6 +1067,18 @@ entersubsh(int flags)
     }
     if (!(sigtrapped[SIGQUIT] & ZSIG_IGNORED))
 	signal_default(SIGQUIT);
+    /*
+     * sigtrapped[sig] == ZSIG_IGNORED for signals that remain ignored,
+     * but other trapped signals are temporarily blocked when intrap,
+     * and must be unblocked before continuing into the subshell.  This
+     * is orthogonal to what the default handler for the signal may be.
+     *
+     * Start loop at 1 because 0 is SIGEXIT
+     */
+    if (intrap)
+	for (sig = 1; sig < SIGCOUNT; sig++)
+	    if (sigtrapped[sig] && sigtrapped[sig] != ZSIG_IGNORED)
+		signal_unblock(signal_mask(sig));
     if (!job_control_ok)
 	opts[MONITOR] = 0;
     opts[USEZLE] = 0;