Some systems will fail hostname() if buf too small, others won't, but
will truncate the name and not leave it '\0'-terminated. Apps end up
adding their own logic to '\0'-terminate it, but rarely add logic to
determine whether or not it was truncated. The app may or may not
work differently on systems where hostname() returns -1 if buf is too
small.
To move some of the gorpy logic out of the app, I changed
apr_gethostname() to zap any truncated buffer if hostname() failed
outright or if it returned a truncated name, and to return an error if
either of these occurred. Thus, the sloppy app can't mistakenly use a
truncated hostname and the good app gets a failure on all APR
platforms if the buffer is too small.
Any further suggestions?
(same change needed in win32/sockopt.c and os2/sockopt.c)
Index: include/apr_network_io.h
===================================================================
RCS file: /cvs/apache/apr/include/apr_network_io.h,v
retrieving revision 1.112
diff -u -r1.112 apr_network_io.h
--- apr_network_io.h 2001/11/13 19:35:15 1.112
+++ apr_network_io.h 2001/11/19 15:18:06
@@ -407,8 +407,9 @@
* Get name of the current machine
* @param buf A buffer to store the hostname in.
* @param len The maximum length of the hostname that can be stored in the
- * buffer provided.
+ * buffer provided. The suggested length is APRMAXHOSTLEN + 1.
* @param cont The pool to use.
+ * @remark If the buffer was not large enough, an error will be returned.
*/
APR_DECLARE(apr_status_t) apr_gethostname(char *buf, int len, apr_pool_t
*cont);
Index: network_io/unix/sockopt.c
===================================================================
RCS file: /cvs/apache/apr/network_io/unix/sockopt.c,v
retrieving revision 1.48
diff -u -r1.48 sockopt.c
--- sockopt.c 2001/07/30 17:56:16 1.48
+++ sockopt.c 2001/11/19 15:18:09
@@ -293,10 +293,18 @@
apr_status_t apr_gethostname(char *buf, apr_int32_t len, apr_pool_t *cont)
{
- if (gethostname(buf, len) == -1)
+ if (gethostname(buf, len) == -1) {
+ buf[0] = '\0';
return errno;
- else
- return APR_SUCCESS;
+ }
+ else if (!memchr(buf, '\0', len)) { /* buffer too small */
+ /* note... most platforms just truncate in this condition
+ * linux+glibc return an error
+ */
+ buf[0] = '\0';
+ return APR_ENAMETOOLONG;
+ }
+ return APR_SUCCESS;
}
#if APR_HAS_SO_ACCEPTFILTER
--
Jeff Trawick | [EMAIL PROTECTED] | PGP public key at web site:
http://www.geocities.com/SiliconValley/Park/9289/
Born in Roswell... married an alien...
