Fix implicit/explicit port in mysqlnd

[kamil-tekiela]

Fixes #8978 (partially). Ref #10922

@nielsdos I had another look at this. I observed that the connection is opened just fine even with the doubled port. The SSL fails due to missing certificate. However, the error message was incorrect and misleading. I don't know if we should still fix the doubled port, but at least to fix the reported issue we should only fix error message. What do you think?

[nielsdos]

This patch as-is makes sense. This can go in as a separate fix.

I don't know if we should still fix the doubled port

So the connection will still fail because of this problem, right?
I believe it should be fixed, can be seperate from this PR.

Actually, the patch from #10922 can be used with a little modification to make it work with ipv6.
The problem in that PR was strchr(hostname.s, ':') == NULL because : may occur in ipv6 addresses.

AFAIK ipv6 is only supported with square brackets right?
In that case we may modify your original PR code to:

if (strchr(hostname.s, ':') == NULL || (hostname.s[0] == '[' && strstr(hostname.s, "]:") == NULL)) {
	transport.l = mnd_sprintf(&transport.s, 0, "tcp://%s:%u", hostname.s, port);
} else {
	transport.l = mnd_sprintf(&transport.s, 0, "tcp://%s", hostname.s);
}

I believe that would do the right thing?

[kamil-tekiela]

So the connection will still fail because of this problem, right?
I believe it should be fixed, can be seperate from this PR.

That I do not know as I was not able to reproduce this. That's why I am not going to pursue that fix anymore.

[nielsdos]

So the connection will still fail because of this problem, right?
I believe it should be fixed, can be seperate from this PR.

That I do not know as I was not able to reproduce this. That's why I am not going to pursue that fix anymore.

Aha okay, that makes sense.