[BUG & PATCH] USR2 traps aren't reset in subshells

[BUG & PATCH] USR2 traps aren't reset in subshells

[Philippe Altherr]

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The documentation states that traps defined for signals are reset in
subshells. This doesn't happen for the signal USR2. I couldn't find an
exception for USR2 neither in the documentation nor in the source code. It
looks like the discrepancy is due to an off by one error, see the proposed
patch.

Here is the script used to exhibit the bug:

bug.zsh:

> #!/bin/zsh

zmodload zsh/system;
> trap "echo Caught $1" $1;
> kill -$1 $sysparams[pid];
> echo Still alive;
> (
>   kill -$1 $sysparams[pid];
>   echo Should NOT be reached;
> )


And here is a run log that exhibits the bug:

% ./bug.zsh HUP
> Caught HUP
> Still alive
> % ./bug.zsh USR1
> Caught USR1
> Still alive
> % ./bug.zsh USR2
> Caught USR2
> Still alive
> Caught USR2
> Should NOT be reached


Philippe

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diff --git a/Src/exec.c b/Src/exec.c
index 097e0b368..00278ac50 100644
--- a/Src/exec.c
+++ b/Src/exec.c
@@ -1089,7 +1089,7 @@ entersubsh(int flags, struct entersubsh_ret *retp)
     int i, sig, monitor, job_control_ok;
 
     if (!(flags & ESUB_KEEPTRAP))
-	for (sig = 0; sig < SIGCOUNT; sig++)
+	for (sig = 0; sig <= SIGCOUNT; sig++)
 	    if (!(sigtrapped[sig] & ZSIG_FUNC) &&
 		!(isset(POSIXTRAPS) && (sigtrapped[sig] & ZSIG_IGNORED)))
 		unsettrap(sig);
@@ -1203,7 +1203,7 @@ entersubsh(int flags, struct entersubsh_ret *retp)
      * Start loop at 1 because 0 is SIGEXIT
      */
     if (intrap)
-	for (sig = 1; sig < SIGCOUNT; sig++)
+	for (sig = 1; sig <= SIGCOUNT; sig++)
 	    if (sigtrapped[sig] && sigtrapped[sig] != ZSIG_IGNORED)
 		signal_unblock(signal_mask(sig));
     if (!job_control_ok)

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#!/bin/zsh
zmodload zsh/system;
trap "echo Caught $1" $1;
kill -$1 $sysparams[pid];
echo Still alive;
(
  kill -$1 $sysparams[pid];
  echo Should NOT be reached;
)