Soon we will allow for multiple datapath implementations. By allowing
the datapath to choose the port numbers, we possibly simplify some datapath
implementations, and the datapath's clients don't have to guess (or to
check) what port numbers are free, so this seems like a better way to go.
This function is easier for callers to use if they do not have to guess
how many ports are in the group. Since it's not performance critical at
all, introduce these easier semantics.
dpif_id() is often used in error messages, e.g. "dp%u: screwed up". But
soon we will be generalizing the concept of a datapath, so it is better
to have a function that returns a full name, e.g. "%s: screwed up".
Accordingly, this commit replaces dpif_id() by a new function dpif_name()
that does so.
The glibc 2.7 headers contain a bug that causes strtok_r() to segfault
in some circumstances. Until now, we have been working around this
problem at each invocation, but this depends on the programmer to remember
to do so each time.
This commit instead adds a shim that adds a work-around to the string.h
header itself, so that it is much more difficult to miss the workaround.
