Jilles Tjoelker <jil...@stack.nl> wrote:
> In some cases the shell executes a subshell or an external command in
> the current process. This is not done if a trap on EXIT has been set, so
> that that trap can execute after the subshell or external command has
> finished. Extend that check to all traps. (A trap is "set" if a
> non-empty command string has been attached to it.)
>
> Improve encapsulation by exporting an accessor function for this and
> making the trap array static again.
>
> This is much like FreeBSD SVN r194127, enhanced to apply to subshells
> also (see FreeBSD SVN r194774).
>
> Example:
> dash -c '{ trap "echo moo" TERM; sleep 3; }& sleep 1; kill $!;wait'
> This should print "moo" after 3 seconds.
>
> Example:
> dash -c '{ trap "echo moo" TERM; (sleep 3) }& sleep 1; kill $!;wait'
> The same.
>
> Example:
> dash -c '{ trap "echo moo" TERM; sleep 3; :; }& sleep 1; kill $!;wait'
> This works correctly even without this patch.
>
> Signed-off-by: Jilles Tjoelker <jil...@stack.nl>
I've applied it with some changes. In particuar, I've made the
have_traps code done using a count kept up-to-date by trapcmd
and clear_traps. Let me know if you see any problems with this.
diff --git a/ChangeLog b/ChangeLog
index 650899a..969d6be 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2010-05-27 Jilles Tjoelker <jil...@stack.nl>
+
+ * Force fork if any trap is set, not just on EXIT.
+
2010-05-27 Herbert Xu <herb...@gondor.apana.org.au>
* Fix poplocalvar on abnormal exit from function.
diff --git a/src/eval.c b/src/eval.c
index d5c1e6c..439f881 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -449,7 +449,7 @@ evalsubshell(union node *n, int flags)
int status;
expredir(n->nredir.redirect);
- if (!backgnd && flags & EV_EXIT && !trap[0])
+ if (!backgnd && flags & EV_EXIT && !have_traps())
goto nofork;
INTOFF;
jp = makejob(n, 1);
@@ -836,7 +836,7 @@ bail:
switch (cmdentry.cmdtype) {
default:
/* Fork off a child process if necessary. */
- if (!(flags & EV_EXIT) || trap[0]) {
+ if (!(flags & EV_EXIT) || have_traps()) {
INTOFF;
jp = makejob(cmd, 1);
if (forkshell(jp, cmd, FORK_FG) != 0) {
diff --git a/src/trap.c b/src/trap.c
index 3f93c46..ba32da6 100644
--- a/src/trap.c
+++ b/src/trap.c
@@ -69,7 +69,9 @@
/* trap handler commands */
-char *trap[NSIG];
+static char *trap[NSIG];
+/* number of non-null traps */
+int trapcnt;
/* current value of signal */
char sigmode[NSIG - 1];
/* indicates specified signal received */
@@ -125,11 +127,17 @@ trapcmd(int argc, char **argv)
if (action) {
if (action[0] == '-' && action[1] == '\0')
action = NULL;
- else
+ else {
+ if (*action)
+ trapcnt++;
action = savestr(action);
+ }
}
- if (trap[signo])
+ if (trap[signo]) {
+ if (*trap[signo])
+ trapcnt--;
ckfree(trap[signo]);
+ }
trap[signo] = action;
if (signo != 0)
setsignal(signo);
@@ -150,16 +158,17 @@ clear_traps(void)
{
char **tp;
+ INTOFF;
for (tp = trap ; tp < &trap[NSIG] ; tp++) {
if (*tp && **tp) { /* trap not NULL or SIG_IGN */
- INTOFF;
ckfree(*tp);
*tp = NULL;
if (tp != &trap[0])
setsignal(tp - trap);
- INTON;
}
}
+ trapcnt = 0;
+ INTON;
}
diff --git a/src/trap.h b/src/trap.h
index f19a66b..50fc3ed 100644
--- a/src/trap.h
+++ b/src/trap.h
@@ -36,7 +36,7 @@
#include <signal.h>
-extern char *trap[];
+extern int trapcnt;
extern char sigmode[];
extern volatile sig_atomic_t pendingsigs;
@@ -49,3 +49,8 @@ int dotrap(void);
void setinteractive(int);
void exitshell(void) __attribute__((__noreturn__));
int decode_signal(const char *, int);
+
+static inline int have_traps(void)
+{
+ return trapcnt;
+}
Thanks,
--
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <herb...@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
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