If the remote DNS server address value of a DHCP server changes, the affected
interfaces do a link down/up to inform all DHCP clients that they should
re-request their DHCP info.
Issue #2730
The dns_server_from attribute of the dhcp-server tag has effect only if
the dns_server attribute of the same tag is not set. If this is the
case, the dns_server_from attribute states the domain from whose IP
config to take the DNS server address. This is useful, for instance, if
the stated domain receives the address of a local DNS server via DHCP.
Whenever the IP config of the stated domain becomes invalid, the DHCP
server switches to a mode where it drops all requests unanswered until
the IP config becomes valid again.
Issue #2730
Until now, the DHCP server of a domain was re-constructed each time the
IP config changed. This is not necessary as a domain that acts as DHCP
server must have a static IP config as it would be senseless to act as
DHCP server and client at the same time. Now, a configured DHCP server
is constructed only when the Domain gets constructed and stays alive
until the domain gets destructed. Furthermore, we now throw Domain::Invalid
if there is no static IP config plus a DHCP server configured. However, by
now, this exception is not caught as it is not trivial to destruct the
domain at this point.
Issue #2730
The Interface constructor previously tried to attach to a domain. This
might include sending a DHCP request to get the domain a valid IP config.
But in order to achieve this, the constructor used a pure virtual method
of Interface which crashes due to the unfinished vtable. To fix this bug,
the attach attempt was moved to a new Interface::init method.
Issue #2730
Instead of Pointer<T>::set use assignment operator with implicit constructor
from T-reference. Instead of Pointer<T>::unset use assignment operator with
Pointer<T>(). Instead of Pointer<T>::deref provide () operator.
Issue #2730
The router reacts as follows to a configuration change:
1) Construct new internal configuration representation (the old one stays
in place to be able to do comparisons in the following steps)
2) Iterate through all user-dependent objects (interfaces, link states, ARP
information, DHCP information) and re-check which remain valid with the
new configuration and which must be dismissed.
3) Adapt the objects that remain valid to the new configuration (re-write
references) and remove or detach the dismissed objects.
4) Do a link state DOWN at each interface and a link state UP at each
interface that remains attached to a domain.
5) Replace the old internal configuration representation with the new one
This way, the router keeps as much user dependent states as possible
while going through a configuration change. Thus, overwriting the old
configuration with an exact copy of itself is (almost) transparent to
clients of the router. Almost, because there are things the router must
do on every configuration handling, like re-scheduling the expiration
timeouts of links.
Ref #2670
The for_each method of the List wrapper remembers the next list item
before calling the functor on the current one, so, the current one can
be destroyed during the functor.
Ref #2670
Clients can connect at any time to the NIC router. The interfaces (sessions)
get attached to the appropriate domain as soon as it appears. This implies
that interfaces can also be detached from a domain without beeing destructed
when the domain disappears. All user dependent states of an interface such as
the link states, DHCP allocations and ARP information get lost when the
interface gets detached.
Ref #2670
This separates the decision wether to log the received and sent packets
from the 'verbose' attribute. This information is now only logged if
'verbose_packets' is switched on. If 'verbose' is switched on, only
routing decisions and optional hints are printed.
Ref #2670
This patch adds a safety check to nit_fb to ensures that nit_fb never
runs out of RAM. Should the available RAM not suffice for resizing the
virtual framebuffer to a new mode, it keeps the current mode.
This patch removes the notion of partial writes from the file-system
servers. Since write operations are asynchronously submitted, they are
expected to succeed completely, except for I/O errors. I/O errors are
propagated with the write acknowledgement but those are usually handled
out of band at the client side. Partial writes must never occur because
they would go undetected by clients, which usually don't wait for the
completion of each single write operation.
Until now, most file-system servers returned the number of written bytes
in the acknowledgement packet. If a server managed to write a part of
the request only, it issued the acknowledgement immediately where it
should have cared about writing the remaining part first.
The patch detects such misbehaving server-side code. If partial writes
unexpectedly occur, it prints a message and leaves the corresponding
request unacknowdleged.
Issue #2672
File_system clients may now watch files and directories for changes by
opening a 'Watch_handle' rather than submitting a 'CONTENT_CHANGED'
packet to the server. When a change happens at a node with an open
Watch_handle a CONTENT_CHANGED packet will be sent from the server to
the client. This serializes registration with other handle operations
and separates I/O handle state from notification handle state.
Test at run/fs_rom_update.
Ref #1934
This change enables the use of negative values for the 'initial_width'
and 'initial_height' attributes to specify values that are relative to
the screen size. This is consistent with the meaning of the 'width' and
'height' attributes.
The new 'Terminal_session::size_changed_sigh' RPC function registers a
signal handler that is triggered each time when the terminal size
changes. It enables the client to adjust itself to the new size by
subsequently calling the 'size' RPC function. Of all terminal servers,
only the graphical terminal triggers this signal.
AVL trees can't be copied with the default copy constructor as the
parent pointer of the first item of both of the resulting trees would
point to the original tree. Copying an AVL node, however, generally
violates the integrity of the corresponding tree. The copy constructor
of Avl_tree is used in some places but in those places it can be
replaced easily. So, this commit deletes the copy constructor of
Avl_node_base which makes Avl_node and Avl_tree non-copyable.
Issue #2654
The 'initial_width' and 'initial_height' attributes were added to
accomodate the use-case to set the initial dimensions whenever 'nit_fb'
is used in a dynamic fashion, e.g, in combination with a window manager.
These attributes may not be mixed with the 'width' and 'height'
attributes, which are mostly used when a static size configuration is
desired.
When a NIC session is destructed at the router, we have to remove all ARP
cache entries that match the MAC address of that session. Otherwise the
outdated entries might be re-applied later, leading to wrong destination
MAC addresses in routed packets.
Fixes#2637
This fix handles the case where the focused domain loses its focus
because the currently focused client vanishes. In this case, the focus
will be undefined and the non-focused views of the domain become
tinted again. The refresh should take effect immediately as soon as the
client vanishes.
Instead of having a method validate_size in each packet class, check
sizes in the data accessor of the surrounding packet class. This packet
accessor is the one that casts the data pointer to the desired data type
so it is sensible that it also checks whether the desired type would
exceed the available RAM before doing the cast. This also fits nicely
the fact that for the top-level packet-class of a packet, the size must
not be checked (which was previously done).
Issue #465
The patch adjust the code of the base, base-<kernel>, and os repository.
To adapt existing components to fix violations of the best practices
suggested by "Effective C++" as reported by the -Weffc++ compiler
argument. The changes follow the patterns outlined below:
* A class with virtual functions can no longer publicly inherit base
classed without a vtable. The inherited object may either be moved
to a member variable, or inherited privately. The latter would be
used for classes that inherit 'List::Element' or 'Avl_node'. In order
to enable the 'List' and 'Avl_tree' to access the meta data, the
'List' must become a friend.
* Instead of adding a virtual destructor to abstract base classes,
we inherit the new 'Interface' class, which contains a virtual
destructor. This way, single-line abstract base classes can stay
as compact as they are now. The 'Interface' utility resides in
base/include/util/interface.h.
* With the new warnings enabled, all member variables must be explicitly
initialized. Basic types may be initialized with '='. All other types
are initialized with braces '{ ... }' or as class initializers. If
basic types and non-basic types appear in a row, it is nice to only
use the brace syntax (also for basic types) and align the braces.
* If a class contains pointers as members, it must now also provide a
copy constructor and assignment operator. In the most cases, one
would make them private, effectively disallowing the objects to be
copied. Unfortunately, this warning cannot be fixed be inheriting
our existing 'Noncopyable' class (the compiler fails to detect that
the inheriting class cannot be copied and still gives the error).
For now, we have to manually add declarations for both the copy
constructor and assignment operator as private class members. Those
declarations should be prepended with a comment like this:
/*
* Noncopyable
*/
Thread(Thread const &);
Thread &operator = (Thread const &);
In the future, we should revisit these places and try to replace
the pointers with references. In the presence of at least one
reference member, the compiler would no longer implicitly generate
a copy constructor. So we could remove the manual declaration.
Issue #465
The warning "no interface connected to domain" was introduced when only one NIC
session at a time could be connected to a domain. It should help to track
packet drops that were caused by startup timing issues between servers and
clients. However, a user should watch the "NIC sessions" value of a domain
(verbose_domain_state) instead when debugging packet loss. With support for
multiple sessions per domain, even a non-empty domain may still miss the
session that connects the desired server.
Fix#2629
Previously, all packets that the router wanted to sent were first prepared to
their final state and then copied at once into the packet stream RAM. This is
fine for packets that the router only passes through with modifying merely
a few values. But for packets that the router writes from scratch on its own,
it is better to compose the packet directly in the packet stream RAM.
Fix#2626
Normally, Interface::send always takes the base and size of the RAM region
where a packet was composed and copies this finished packet at once into the
packet stream RAM. But we want to be able to also compose packets directly in
the packet stream RAM, so that no memcpy is needed. Thus, Interface::send now
takes a functor that describes how to compose the packet, then allocates the
packet stream RAM and applies the functor to this RAM. there is also a version
of Interface::send that provides the old behavior but with the new back end.
This way, we stay backwards-compatible.
Issue #2626
When composing an ARP packet for sending, it's pointless to use the Arp_packet
constructor as the constructor only checks whether the packet is malformed.
Issue #2618
The NIC router can now be configured to periodically send reports.
Configuration example (shows default values):
<config>
<report interval_sec="5" bytes="yes" config="yes">
</config>
If the 'report' tag is not available, no reports are send.
The attributes of the 'report' tag:
'bytes' : Boolean : Whether to report sent bytes and received bytes per
domain
'config' : Boolean : Whether to report ipv4 interface and gateway per
domain
'interval_sec' : 1..3600 : Interval of sending reports in seconds
Issue #2614
In the context of link state objects we often used the term "close" were we
actually meant "dissolve". The term "close" originated from the TCP connection
state and is still used in TCP links in the correct manner.
Issue #2609
Act as hub for the interfaces at a domain. This also changes the roles of the
Domain and Interface classes. By now the Interface held the data structures for
the ARP cache, foreign ARP waiters, and the searchtrees for layer 3 links. All
these structures have moved to the Domain while the memory allocations and
lifetime management for the contents of these structures still come from from
the according Interface object. The mentioned data structures were also adapted
to fit the fact that they now may maintain objects of different interfaces.
Issue #2609
If an IPv4 packet targets an IP local to the domain it comes from and doesn't
target the routers IP of that domain, forward it to all other interfaces of
the domain without considering any other routing.
Issue #2609
