On Fri, Apr 15, 2016 at 12:27:20PM +0200, Andrea Bolognani wrote:
Having two "whiles" like that looks kinda off... I'd rather have something like
while (!virTimeBackOffHasExpired(&timeout))
or preferably something better than what I can come up with :)
The trouble is the function doesn't exactly do that. It also performs the delay. ...Wait (suggested elsewhere) was a better idea.
+/** + * virTimeBackOffWhile + * @var: Timeout variable (with type virTimeBackOffVar *). + * + * You must initialize @var first by calling the following function, + * which also starts the timer: + * + * if (virTimeBackOffStart(&var, first, timeout) < 0) { + * // handle errors + * } + * + * Then you use a while loop: + * + * while (virTimeBackOffWhile(&var)) { + * //... + * } + * + * The while loop that runs the body of the code repeatedly, with an + * exponential backoff. It first waits for first milliseconds, then + * runs the body, then waits for 2*first ms, then runs the body again. + * Then 4*first ms, and so on. + * + * When timeout milliseconds is reached, the while loop ends. + * + * The body should use "break" or "goto" when whatever condition it is + * testing for succeeds (or there is an unrecoverable error). + */ +bool virTimeBackOffWhile(virTimeBackOffVar *var); + #endif
API documentation should live in the .c file, like you did with virTimeBackOffStart(). I guess it's just a consequence of the "a" implementation using a macro for this part :)
OK. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com virt-df lists disk usage of guests without needing to install any software inside the virtual machine. Supports Linux and Windows. http://people.redhat.com/~rjones/virt-df/