svn commit: r254621 - head/lib/libutil

[Sergey Kandaurov]

Author: pluknet
Date: Wed Aug 21 22:37:15 2013
New Revision: 254621
URL: http://svnweb.freebsd.org/changeset/base/254621

Log:
  Reset errno before strtoumax() call to properly detect ERANGE.
  Restore saved errno if strtoumax() call is successful.
  
  Reported by:	ache
  Reviewed by:	jilles
  MFC after:	1 week

Modified:
  head/lib/libutil/expand_number.c

Modified: head/lib/libutil/expand_number.c
==============================================================================
--- head/lib/libutil/expand_number.c	Wed Aug 21 22:30:11 2013	(r254620)
+++ head/lib/libutil/expand_number.c	Wed Aug 21 22:37:15 2013	(r254621)
@@ -50,15 +50,22 @@ int
 expand_number(const char *buf, uint64_t *num)
 {
 	uint64_t number;
+	int saved_errno;
 	unsigned shift;
 	char *endptr;
 
+	saved_errno = errno;
+	errno = 0;
+
 	number = strtoumax(buf, &endptr, 0);
 
 	if (number == UINTMAX_MAX && errno == ERANGE) {
 		return (-1);
 	}
 
+	if (errno == 0)
+		errno = saved_errno;
+
 	if (endptr == buf) {
 		/* No valid digits. */
 		errno = EINVAL;