Rework the sysconf(3) interaction with aio:

sysconf.c:
  Use 'break' rather than 'goto yesno' in sysconf.c so that we report a '0'
  return value from the kernel sysctl.

vfs_aio.c:
  Make aio reset its configuration parameters to -1 after unloading
  instead of 0.

posix4_mib.c:
  Initialize the aio configuration parameters to -1
  to indicate that it is not loaded.
  Add a facility (p31b_iscfg()) to determine if a posix4 facility has been
  initialized to avoid having to re-order the SYSINITs.
  Use p31b_iscfg() to determine if aio has had a chance to run yet which
  is likely if it is compiled into the kernel and avoid spamming its
  values.
  Introduce a macro P31B_VALID() instead of doing the same comparison over
  and over.

posix4.h:
  Prototype p31b_iscfg().

1 files changed, 3 insertions, 6 deletions

diff --git a/lib/libc/gen/sysconf.c b/lib/libc/gen/sysconf.c
index aa906f6..ecb833e 100644
--- a/lib/libc/gen/sysconf.c
+++ b/lib/libc/gen/sysconf.c
@@ -254,20 +254,17 @@ do_NAME_MAX:
 		return (_POSIX_TIMERS);
 #endif
 	case _SC_AIO_LISTIO_MAX:
-		defaultresult = _POSIX_AIO_LISTIO_MAX;
 		mib[0] = CTL_P1003_1B;
 		mib[1] = CTL_P1003_1B_AIO_LISTIO_MAX;
-		goto yesno;
+		goto break;
 	case _SC_AIO_MAX:
-		defaultresult = _POSIX_AIO_MAX;
 		mib[0] = CTL_P1003_1B;
 		mib[1] = CTL_P1003_1B_AIO_MAX;
-		goto yesno;
+		goto break;
 	case _SC_AIO_PRIO_DELTA_MAX:
-		defaultresult = 0;
 		mib[0] = CTL_P1003_1B;
 		mib[1] = CTL_P1003_1B_AIO_PRIO_DELTA_MAX;
-		goto yesno;
+		goto break;
 	case _SC_DELAYTIMER_MAX:
 		mib[0] = CTL_P1003_1B;
 		mib[1] = CTL_P1003_1B_DELAYTIMER_MAX;