Since we now have the copy of the target in the session, use it instead
of relying on the SI for it. The SI drops the target upon unregister()
so applets such as stats were logged as "NOSRV".
This patch turns internal server addresses to sockaddr_storage to
store IPv6 addresses, and makes the connect() function use it. This
code already works but some caveats with getaddrinfo/gethostbyname
still need to be sorted out while the changes had to be merged at
this stage of internal architecture changes. So for now the config
parser will not emit an IPv6 address yet so that user experience
remains unchanged.
This change should have absolutely zero user-visible effect, otherwise
it's a bug introduced during the merge, that should be reported ASAP.
This one has been removed and is now totally superseded by ->target.
To get the server, one must use target_srv(&s->target) instead of
s->srv now.
The function ensures that non-server targets still return NULL.
s->prev_srv is used by assign_server() only, but all code paths leading
to it now take s->prev_srv from the existing s->srv. So assign_server()
can do that copy into its own stack.
If at one point a different srv is needed, we still have a copy of the
last server on which we failed a connection attempt in s->target.
When dealing with HTTP keep-alive, we'll have to know if we can reuse
an existing connection. For that, we'll have to check if the current
connection was made on the exact same target (referenced in the stream
interface).
Thus, we need to first assign the next target to the session, then
copy it to the stream interface upon connect(). Later we'll check for
equivalence between those two operations.
Now that we have the target pointer and type in the stream interface,
we don't need the applet.handler pointer anymore. That makes the code
somewhat cleaner because we know we're dealing with an applet by checking
its type instead of checking the pointer is not null.
When doing a connect() on a stream interface, some information is needed
from the server and from the backend. In some situations, we don't have
a server and only a backend (eg: peers). In other cases, we know we have
an applet and we don't want to connect to anything, but we'd still like
to have the info about the applet being used.
For this, we now store a pointer to the "target" into the stream interface.
The target describes what's on the other side before trying to connect. It
can be a server, a proxy or an applet for now. Later we'll probably have
descriptors for multiple-stage chains so that the final information may
still be found.
This will help removing many specific cases in the code. It already made
it possible to remove the "srv" and "be" parameters to tcpv4_connect_server().
I/O handlers are still delicate to manipulate. They have no type, they're
just raw functions which have no knowledge of themselves. Let's have them
declared as applets once for all. That way we can have multiple applets
share the same handler functions and we can store their names there. When
we later need to add more parameters (eg: usage stats), we'll be able to
do so in the applets themselves.
The CLI functions has been prefixed with "cli" instead of "stats" as it's
clearly what is going on there.
The applet descriptor in the stream interface should get all the applet
specific data (st0, ...) but this will be done in the next patch so that
we don't pollute this one too much.