This patch unifies the patterns of using the 'Genode' and 'Libc'
namespaces.
Types defined in the 'internal/' headers reside in the 'Libc'
namespace. The code in the headers does not need to use the
'Libc::' prefix.
Compilation units import the 'Libc' namespace after the definition of
local types. Local types reside in the 'Libc' namespace (and should
eventually move to an 'internal/' header).
Since the 'Libc' namespace imports the 'Genode' namespace, there is
no need to use the 'Genode::' prefix. Consequently, code in the
compilation units rarely need to qualify the 'Genode' or 'Libc'
namespaces.
There are a few cases where the 'Libc', the 'Genode', and the global
(libc) namespaces are ambigious. In these cases, an explicit
clarification is needed:
- 'Genode::Allocator' differs from 'Libc::Allocator'.
- 'Genode::Env' differs from 'Libc::Env'.
- Genode's string functions (strcmp, memcpy, strcpy) conflict
with the names of the (global) libc functions.
- There exist both 'Genode::uint64_t' and the libc'c 'uint64_t'.
Issue #3497
This patch is the first step of re-organizing the internal structure of
the libc. The original version involved many direct calls of global
functions (often with side effects) across compilation units, which
made the control flow (e.g., the initialization sequence) hard to
follow.
The new version replaces those ad-hoc interactions with dedicated
interfaces (like suspend.h, resume.h, select.h, current_time.h). The
underlying facilities are provided by the central Libc::Kernel and
selectively propagated to the various compilation units. The latter is
done by a sequence of 'init_*' calls, which eventually will be replaced
by constructor calls.
The addition of new headers increases the chance for name clashes with
existing (public) headers. To disambiguate libc-internal header files
from public headers, this patch moves the former into a new 'internal/'
subdirectory. This makes the include directives easier to follow and the
libc's source-tree structure more tidy.
There are still a few legacies left, which cannot easily be removed
right now (e.g., because noux relies on them). However, the patch moves
those bad apples to legacy.h and legacy.cc, which highlights the
deprecation of those functions.
Issue #3497
- readv_writev: move 'rw_lock' instance into a function scope,
constructing the instance on the first access.
- select: move 'select_cb_list' instance into function scope.
- thread: move 'key_list_lock' and 'keys' into function scope.
- rwlock, semaphore, socket_fs_plugin, thread, thread_create:
instantiate 'Libc::Allocator' per use, alleviating the need for a
global instance.
Issue #3496
Implement getifaddrs and freeifaddrs within the libc using socket
control files at the VFS. Add an "address" and "netmask" file to the
lwIP plugin.
Only a single IPv4 address is initially supported, and the broadcast
address returned will never be valid.
Fixes#3439
By using Genode::strncpy instead of the libc's strncpy, we cannot end up
in the situation where the result lacks the zero termination (where the
number of charactors equals the destination buffer size).
For better or worse we have no proper way of handling this right now
but contrib libraries, e.g. glib, use it to determine if they can use
the underlying fd.
Fxies #3265.
This patch reintroduces the LwIP stack to libc as a VFS plugin
implementing the socket_fs interface. Rather than use LwIP's socket
emulation layer this plugin interfaces directly to LwIP raw API and is
single threaded.
The internal TCP parameters of the stack are untuned.
Fix#2050Fix#2335
Generic code that operates over both UDP and TCP sockets might use
'sendto', but in the case of TCP the destination address ought to be
safely discarded. This seems to be the case for certain DNS software
that operates over both UDP and TCP.
Fix#2807
Socket_fs sockets are now created each time a 'new_socket' control file
is opened, not each time a 'new_socket' file is read. When a handle on a
'new_socket' file is closed the socket and its socket files are
destroyed. The accept control file on a listening socket reads "1" or
reads nothing to indicate a client connection is queued. Client sockets
are accepted by opening an 'accept_socket' file in the listen socket
directory. This file behaves like the aforementioned 'new_socket' file.
Ref #2707
This prevents diagnostic messages like
Error: partial write detected 0 vs 31
for writes into already released socket directories due to a still-open
handle to the socket data file.
There are programs, e.g. curl, that check if a connection was
established successfully by looking at SO_ERROR. Pretend that
the getsockopt() call was executed to keep them happy. If they
try to use a broken connection, the other socket functions will
bail.
If 'close' does not call 'unlink' like 'shutdown', the Lxip_socket_dir
never gets destroyed and thus the socket server leaks resources like
RAM and ports.
Ref #2285
Our 'shutdown' implementation handles only the case that 'how' is 'RDWR'.
Thus, print an error and continue if a user calls it with another value.
Fixes#2285
The socket file system can be configured in the "socket" attribute of
the libc config node like follows.
<vfs> <dir name="socket"> <fs/> </dir> </vfs>
<libc ... socket="/socket"/>
This configures the socket file system libc backend to access files in
"/socket" for socket operations.