if_start can be called recursively via if_encap. Avoid this as our
scheme of dequeuing packets is not compatible with this.

CC: Fabien Chouteau <chouteau@adacore.com>
CC: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
CC: Stefan Weil <sw@weilnetz.de>
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>

Make sure that next_m always points to a packet if batchq is non-empty.
This will simplify walking the queues in if_start.

CC: Fabien Chouteau <chouteau@adacore.com>
CC: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
CC: Stefan Weil <sw@weilnetz.de>
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>

Replace gotos with a while loop, fix coding style.

CC: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
CC: Fabien Chouteau <chouteau@adacore.com>
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>

In case we requeued a packet that was the head of a longer session
queue, we failed to restore this ordering. Also, we did not properly
deal with changes to Slirp::next_m.

Instead of a cumbersome roll back, this fix simply avoids any changes
until we know if the packet was actually sent. Both fixes crashes due
to inconsistent queues and simplifies the logic.

Thanks to Zhi Yong Wu who found the reason for these crashes.

CC: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
CC: Fabien Chouteau <chouteau@adacore.com>
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>

Remove duplicate ifs_init macros, reimplement the logic as static inline
in mbuf.h.

CC: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
CC: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>

The expiration timeout must only affect packets that are queued due to
pending ARP resolutions. The old version broke ping e.g.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>

No need to update the current time for each packet we send from the
queue. Processing time is comparably short.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>

In the current implementation, if Slirp tries to send an IP packet to a client
with an unknown hardware address, the packet is simply dropped and an ARP
request is sent (if_encap in slirp/slirp.c).

With this patch, Slirp will send the ARP request, re-queue the packet and try
to send it later. The packet is dropped after one second if the ARP reply is
not received.
Signed-off-by: NFabien Chouteau <chouteau@adacore.com>
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>

This now also exports the internal state to the slirp users in qemu,
returning it from slirp_init and expecting it along with service
invocations. Additionally provide an opaque value interface for the
callbacks from slirp into the qemu core.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

The essence of this patch is to stuff (almost) all global variables of
the slirp stack into the structure Slirp. In this step, we still keep
the structure as global variable, directly accessible by the whole
stack. Changes to the external interface of slirp will be applied in
the following patches.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

link_up is true once slirp is initialized, so these check are really not
required.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

After all its years inside the qemu tree, there is no point in keeping
the dead code paths of slirp. This patch is a first round of removing
usually commented out code parts. More cleanups need to follow (and
maybe finally a proper reindention).
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Fix Sparse warnings:
 * use NULL instead of plain 0
 * rearrange header include order to avoid redefining types accidentally
 * ANSIfy SLIRP
 * avoid "restrict" keyword
 * add static



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6736 c046a42c-6fe2-441c-8c8c-71466251a162

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5363 c046a42c-6fe2-441c-8c8c-71466251a162

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5021 c046a42c-6fe2-441c-8c8c-71466251a162

At the same time remove a bogus test (tested by Jason Wessel).
Quiet some gcc4 warnings from slirp compilation.


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4402 c046a42c-6fe2-441c-8c8c-71466251a162

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@3453 c046a42c-6fe2-441c-8c8c-71466251a162

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@3452 c046a42c-6fe2-441c-8c8c-71466251a162

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git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@1911 c046a42c-6fe2-441c-8c8c-71466251a162

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git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@1067 c046a42c-6fe2-441c-8c8c-71466251a162

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