[src/trunk]: src/sys/kern simplify, no need for va_copy here. Add KASSERT.

[christos <christos%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/22aae567e1c3
branches:  trunk
changeset: 771444:22aae567e1c3
user:      christos <christos%NetBSD.org@localhost>
date:      Sun Nov 20 22:58:31 2011 +0000

description:
simplify, no need for va_copy here. Add KASSERT.

diffstat:

 sys/kern/subr_kmem.c |  24 +++++++++++-------------
 1 files changed, 11 insertions(+), 13 deletions(-)

diffs (51 lines):

diff -r 22e5d52ce1db -r 22aae567e1c3 sys/kern/subr_kmem.c
--- a/sys/kern/subr_kmem.c      Sun Nov 20 22:50:12 2011 +0000
+++ b/sys/kern/subr_kmem.c      Sun Nov 20 22:58:31 2011 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: subr_kmem.c,v 1.37 2011/11/20 21:27:26 apb Exp $       */
+/*     $NetBSD: subr_kmem.c,v 1.38 2011/11/20 22:58:31 christos Exp $  */
 
 /*-
  * Copyright (c) 2009 The NetBSD Foundation, Inc.
@@ -63,7 +63,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: subr_kmem.c,v 1.37 2011/11/20 21:27:26 apb Exp $");
+__KERNEL_RCSID(0, "$NetBSD: subr_kmem.c,v 1.38 2011/11/20 22:58:31 christos Exp $");
 
 #include <sys/param.h>
 #include <sys/callback.h>
@@ -472,23 +472,21 @@
 char *
 kmem_asprintf(const char *fmt, ...)
 {
-       int size, str_len;
-       va_list va, va2;
+       int size, len;
+       va_list va;
        char *str;
-       char buf[1];
        
        va_start(va, fmt);
-       va_copy(va2, va);
-       str_len = vsnprintf(buf, sizeof(buf), fmt, va) + 1;
+       len = vsnprintf(NULL, 0, fmt, va);
        va_end(va);
 
-       str = kmem_alloc(str_len, KM_SLEEP);
+       str = kmem_alloc(len + 1, KM_SLEEP);
 
-       if ((size = vsnprintf(str, str_len, fmt, va2)) == -1) {
-               kmem_free(str, str_len);
-               return NULL;
-       }
-       va_end(va2);
+       va_start(va, fmt);
+       size = vsnprintf(str, len + 1, fmt, va);
+       va_end(va);
+
+       KASSERT(size == len);
 
        return str;
 }