Fix problem with traps not runing if shell exec'd final command

3 files changed, 24 insertions, 3 deletions

diff --git a/ChangeLog b/ChangeLog
index 4d5402a0b..358fa6f5c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2001-03-30  Peter Stephenson  <pws@csr.com>
+
+	* 13851: Src/signals.c, Src/exec.c: don't exec final command in
+	in list if any traps are set, since we don't know whether we will
+	need to handle them when that command exits.
+
 2001-03-30  Bart Schaefer  <schaefer@zsh.org>
 
 	* 13846: Test/ztst.zsh: When "make check" is run with output to a
diff --git a/Src/exec.c b/Src/exec.c
index fa49c3137..073bea456 100644
--- a/Src/exec.c
+++ b/Src/exec.c
@@ -1954,7 +1954,7 @@ execcmd(Estate state, int input, int output, int how, int last1)
      *    be needed after the current command.  This is typically the case    *
      *    when when the command is the last stage in a subshell, or is the    *
      *    last command after the option `-c'.                                 *
-     * 2) We are not trapping EXIT or ZERR.                                   *
+     * 2) We don't have any traps set.                                        *
      * 3) We don't have any files to delete.                                  *
      *                                                                        *
      * The condition above for a `fake exec' will also work for a current     *
@@ -1966,8 +1966,7 @@ execcmd(Estate state, int input, int output, int how, int last1)
     if ((how & Z_ASYNC) ||
 	(!do_exec &&
 	 (((is_builtin || is_shfunc) && output) ||
-	  (!is_cursh && (last1 != 1 || sigtrapped[SIGZERR] ||
-			 sigtrapped[SIGEXIT] || havefiles()))))) {
+	  (!is_cursh && (last1 != 1 || nsigtrapped || havefiles()))))) {
 
 	pid_t pid;
 	int synch[2];
diff --git a/Src/signals.c b/Src/signals.c
index 7ff4fca9d..d664f80c3 100644
--- a/Src/signals.c
+++ b/Src/signals.c
@@ -41,6 +41,11 @@ mod_export int sigtrapped[VSIGCOUNT];
 /**/
 mod_export Eprog sigfuncs[VSIGCOUNT];
 
+/* Total count of trapped signals */
+
+/**/
+mod_export int nsigtrapped;
+
 /* Variables used by signal queueing */
 
 /**/
@@ -716,6 +721,7 @@ settrap(int sig, Eprog l)
             sig != SIGCHLD)
             signal_ignore(sig);
     } else {
+	nsigtrapped++;
         sigtrapped[sig] = ZSIG_TRAPPED;
         if (sig && sig <= SIGCOUNT &&
 #ifdef SIGWINCH
@@ -773,6 +779,8 @@ removetrap(int sig)
 	unqueue_signals();
         return NULL;
     }
+    if (sigtrapped[sig] & ZSIG_TRAPPED)
+	nsigtrapped--;
     sigtrapped[sig] = 0;
     if (sig == SIGINT && interact) {
 	/* PWS 1995/05/16:  added test for interactive, also noholdintr() *
@@ -860,6 +868,8 @@ endtrapscope(void)
 	    exitfn = sigfuncs[SIGEXIT];
 	}
 	sigfuncs[SIGEXIT] = NULL;
+	if (sigtrapped[SIGEXIT] & ZSIG_TRAPPED)
+	    nsigtrapped--;
 	sigtrapped[SIGEXIT] = 0;
     }
 
@@ -878,6 +888,12 @@ endtrapscope(void)
 		dontsavetrap++;
 		settrap(sig, prog);
 		dontsavetrap--;
+		/*
+		 * counting of nsigtrapped should presumably be handled
+		 * in settrap...
+		 */
+		DPUTS((sigtrapped[sig] ^ st->flags) & ZSIG_TRAPPED,
+		      "BUG: settrap didn't restore correct ZSIG_TRAPPED");
 		if ((sigtrapped[sig] = st->flags) & ZSIG_FUNC)
 		    shfunctab->addnode(shfunctab, ((Shfunc)st->list)->nam,
 				       (Shfunc) st->list);