Report the correct stack size and top for the primordial thread in

pthread_stackseg_np(). With input and okay marc@

1 files changed, 18 insertions, 15 deletions

diff --git a/lib/libpthread/uthread/uthread_stackseg_np.c b/lib/libpthread/uthread/uthread_stackseg_np.c
index cd423aeaf9a..c2a981c3a57 100644
--- a/lib/libpthread/uthread/uthread_stackseg_np.c
+++ b/lib/libpthread/uthread/uthread_stackseg_np.c
@@ -1,9 +1,11 @@
-/* $OpenBSD: uthread_stackseg_np.c,v 1.5 2007/05/18 19:28:50 kurt Exp $ */
+/* $OpenBSD: uthread_stackseg_np.c,v 1.6 2007/07/08 01:53:46 kurt Exp $ */
 
 /* PUBLIC DOMAIN: No Rights Reserved. Marco S Hyman <marc@snafu.org> */
 
 #include <sys/param.h>
+#include <sys/time.h>
 #include <sys/lock.h>
+#include <sys/resource.h>
 #include <sys/queue.h>
 
 #include <errno.h>
@@ -27,6 +29,7 @@ pthread_stackseg_np(pthread_t thread, stack_t *sinfo)
 	char *base;
 	size_t pgsz;
 	int ret;
+	struct rlimit rl;
 
 	if (thread->stack) {
 		base = thread->stack->base;
@@ -38,22 +41,22 @@ pthread_stackseg_np(pthread_t thread, stack_t *sinfo)
 		sinfo->ss_flags = 0;
 		ret = 0;
 	} else if (thread == _thread_initial) {
+		if (getrlimit(RLIMIT_STACK, &rl) != 0)
+			return (EAGAIN);
 		pgsz = (size_t)sysconf(_SC_PAGESIZE);
 		if (pgsz == (size_t)-1)
-			ret = EAGAIN;
-		else {
-#if defined(MACHINE_STACK_GROWS_UP)
-			base = (caddr_t) USRSTACK;
-#else
-			base = (caddr_t) ((USRSTACK - DFLSSIZ) & ~(pgsz - 1));
-			base += DFLSSIZ;
-#endif
-			sinfo->ss_sp = base;
-			sinfo->ss_size = DFLSSIZ;
-			sinfo->ss_flags = 0;
-			ret = 0;
-		}
-
+			return (EAGAIN);
+		/*
+		 * round_page() stack rlim_cur and
+		 * trunc_page() USRSTACK to be consistent with
+		 * the way the kernel sets up the stack.
+		 */
+		sinfo->ss_size = (size_t)rl.rlim_cur;
+		sinfo->ss_size += (pgsz - 1);
+		sinfo->ss_size &= ~(pgsz - 1);
+		sinfo->ss_sp = (caddr_t) (USRSTACK & ~(pgsz - 1));
+		sinfo->ss_flags = 0;
+		ret = 0;
 	} else
 		ret = EAGAIN;