[Linux-ha-dev] heartbeat per-link status and nice failback enhancements

[Alan Robertson]

Michael Moerz wrote:
> 
> On Mon, 27 Mar 2000, Alan Robertson wrote:
> 
> > You're not appending a (char*) to the string, so you shouldn't use
> > sizeof(char*).  Perhaps you meant sizeof(char) or 2*sizeof(char)?  I
> > forget if the stringlen field includes the terminating NULL or not.
> 
> I think that strlen doesn't count NULL - values, so you have to add it
> yourself if you're calculating the memroy consumption.
> 
> kind regards,
> Michael Moerz Systemengineer
> CUBIT IT-Solutions

The line in question was:

	buf = ha_malloc(m->stringlen +
		((strlen(iface) + sizeof(IFACE)) * sizeof(char *)));

But, the field "m->stringlen" already includes space for a NULL byte.  I
went back and reread the code.  So, Marcelo didn't need to leave room
for an additional one.  This field is initialized in function
ha_msg_new() in this way:

	ret->stringlen  = sizeof(MSG_START)+sizeof(MSG_END)-1;

So, it leaves room for two strings minus the room for one of the two
NULL
bytes associated with the two constants.  Unlike strlen, sizeof *does*
count the NULL byte.  Perhaps I should have named the field stringspace
instead of stringlen.  To further attest to my intentions, when I copy a
message buffer to a string in function msg2string(), I do this:

	buf = ha_malloc(m->stringlen);

Fortunately, stringlen is a private field only used a handful of times
in only one file, so it's pretty easy to see how it's used.

It's GREAT to have someone else carefully looking over these patches!

	Thanks Michael!

	-- Alan Robertson
	   alanr@suse.com