xnu-6153.101.6.tar.gz

[apple/xnu.git] / libsyscall / mach / string.c

diff --git a/libsyscall/mach/string.c b/libsyscall/mach/string.c
index e1555b49dcca84c88ee048cde879376b83c1bb83..fcb9e6fd2702b78456e819436ecdbe595b2a38df 100644 (file)
--- a/libsyscall/mach/string.c
+++ b/libsyscall/mach/string.c
@@ -2,7 +2,7 @@
  * Copyright (c) 2010 Apple Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
- * 
+ *
  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in
@@ -11,10 +11,10 @@
  * unlawful or unlicensed copies of an Apple operating system, or to
  * circumvent, violate, or enable the circumvention or violation of, any
  * terms of an Apple operating system software license agreement.
- * 
+ *
  * Please obtain a copy of the License at
  * http://www.opensource.apple.com/apsl/ and read it before using this file.
- * 
+ *
  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
@@ -22,7 +22,7 @@
  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  * Please see the License for the specific language governing rights and
  * limitations under the License.
- * 
+ *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 
@@ -48,14 +48,14 @@ _mach_hex(char **buffer, int *length, unsigned long long n)
 {
        char buf[32];
        char *cp = buf + sizeof(buf);
-       
+
        if (n) {
                *--cp = '\0';
                while (n) {
                        *--cp = hex[n & 0xf];
                        n >>= 4;
                }
-               
+
                int width = _mach_strlen(cp);
                while (width > 0 && length > 0) {
                        *(*buffer)++ = *cp++;
@@ -70,7 +70,7 @@ _mach_vsnprintf(char *buffer, int length, const char *fmt, va_list ap)
 {
        int width, max = length;
        char *out_ptr = buffer;
-       
+
        // we only ever write n-1 bytes so we can put a \0 at the end
        length--;
        while (length > 0 && *fmt) {
@@ -86,26 +86,28 @@ _mach_vsnprintf(char *buffer, int length, const char *fmt, va_list ap)
                // only going to support a specific subset of sprintf flags
                // namely %s, %x, with no padding modifiers
                switch (*fmt++) {
-                       case 's':
-                       {
-                               char *cp = va_arg(ap, char*);
-                               width = _mach_strlen(cp);
-                               while (width > 0 && length > 0) {
-                                       *(out_ptr++) = *(cp++);
-                                       width--;
-                                       length--;
-                               }
-                               break;
-                       }
-                       case 'x':
-                       {
-                               _mach_hex(&out_ptr, &length, va_arg(ap, unsigned int));
-                               break;
+               case 's':
+               {
+                       char *cp = va_arg(ap, char*);
+                       width = _mach_strlen(cp);
+                       while (width > 0 && length > 0) {
+                               *(out_ptr++) = *(cp++);
+                               width--;
+                               length--;
                        }
+                       break;
+               }
+               case 'x':
+               {
+                       _mach_hex(&out_ptr, &length, va_arg(ap, unsigned int));
+                       break;
+               }
                }
        }
-       *out_ptr = '\0';
-       return max - length;
+       if (max > 0) {
+               *out_ptr = '\0';
+       }
+       return max - (length + 1); /* don't include the final NULL in the return value */
 }
 
 int