Re: [libvirt] [patch 2/5] Instantiate comments in ip(6)tables rules
On 09/24/2010 01:38 PM, Stefan Berger wrote:
To prevent consecutive spaces in comments from becoming a single
space
(by bash), the IFS variable is now set to an empty string. Also, commands
are now executed using bash's 'eval' command.
-#define CMD_EXEC "res=`${cmd}`" CMD_SEPARATOR
+#define CMD_EXEC "res=`eval ${cmd}`" CMD_SEPARATOR
Underquoted. To be robust, this needs to be:
"res=`eval \"$cmd\"" CMD_SEPARATOR
which will then avoid your need for the empty IFS hack and double
escaping (you'll still need single escaping, but that's a bit more
manageable).
+/* avoiding a compiler warning trough own implementation */
+static const char *
+_strchr(const char *s, int c)
+{
+ while (*s && *s != (char)c)
+ s++;
+ if (*s)
+ return s;
+ return NULL;
+}
Ouch. That's probably 4x slower than the glibc version. I'd much
rather see:
#undef strchr
or
(strchr)(a, b)
which then guarantees that you get the function call, rather than the
macro expansion; after all, the macro expansion just defers to the
function call if both arguments are non-constants, not to mention the
fact that the -Wlogical-op warning is only triggered by the macro and
not by the function.
--
Eric Blake eblake(a)redhat.com +1-801-349-2682
Libvirt virtualization library http://libvirt.org