... and set initial time by using RTC session.
Up to now Noux used a monotic clock whose initial start value always
was '0' (which correlates to the start of the UNIX epoch) to provide
a notion of time. In addition it is now possible to use the RTC
session to set the initial value for use cases where having a proper
real-world time matters.
To use the RTC session the 'rtc' attribute of the '<config>' node
must be set to 'yes'. Thereby the session becomes a mandatory
dependency as Noux will not start without it.
Issue #1784
Replace the I/O response handler that is passed to the VFS at
construction with an object that is dynamically attached to handles.
This object shall also accept read-ready notifications, and plugins are
encouraged to keep handles awaiting ready-ready notifications separate
from handles that await I/O progress.
Replace the use of handle lists in plugins with handle queues, this
makes the code easier to understand and the ordering of notifications to
the application more explicit.
These changes replace the use of the Post_signal_hook from all VFS
plugins, applications must assume that read-ready and I/O notifications
occur during I/O signal dispatch and use an Io_progress_handler at its
entrypoints to defer response until after signal dispatching.
Fix#3257
Calling 'handle_io_response()' in a regular VFS function (in contrast to a
post-signal hook) can cause problems if the caller of the VFS function holds
a lock which prevents the io response handler from returning.
With this commit, the user of the VFS becomes responsible for unblocking
threads which might be blocking after a failed 'queue_read()', 'queue_sync()'
or 'write()' call.
Fixes#2896
Reduce the size and forward compatibility of VFS file-system
constructors by passing an object holding accessors for 'Genode::Env',
'Genode::Allocator', response handlers, and the root file-system.
Fix#2742
Channels, and therefore contexts, may be shared between children
causing corruption when a child is destroyed while another child still
uses the old context within the channel.
related to #2601
The VFS library can be used in single-threaded or multi-threaded
environments and depending on that, signals are handled by the same thread
which uses the VFS library or possibly by a different thread. If a VFS
plugin needs to block to wait for a signal, there is currently no way
which works reliably in both environments.
For this reason, this commit makes the interface of the VFS library
nonblocking, similar to the File_system session interface.
The most important changes are:
- Directories are created and opened with the 'opendir()' function and the
directory entries are read with the recently introduced 'queue_read()'
and 'complete_read()' functions.
- Symbolic links are created and opened with the 'openlink()' function and
the link target is read with the 'queue_read()' and 'complete_read()'
functions and written with the 'write()' function.
- The 'write()' function does not wait for signals anymore. This can have
the effect that data written by a VFS library user has not been
processed by a file system server yet when the library user asks for the
size of the file or closes it (both done with RPC functions at the file
system server). For this reason, a user of the VFS library should
request synchronization before calling 'stat()' or 'close()'. To make
sure that a file system server has processed all write request packets
which a client submitted before the synchronization request,
synchronization is now requested at the file system server with a
synchronization packet instead of an RPC function. Because of this
change, the synchronization interface of the VFS library is now split
into 'queue_sync()' and 'complete_sync()' functions.
Fixes#2399
The support has two parts. First, a VFS plugin now gets passed an
I/O-response handler callback on construction, which informs users of the
VFS that an I/O event occurred. This enables, for example, the libC to
check if blocking read can be completed. Further, the VFS file I/O
interface provides now functions for suspendable reads, i.e.,
queue_read() and complete_read().
This patch removes the dependency of the deprecated Genode API,
fixes the coding style, and removes the "random" file system
(superseded by the VFS plugin mechanism).
Ref #1987
Opening a VFS handle previously involved allocating from the global heap
at each VFS file system. By amending open with an allocator argument,
dynamic allocation can be partitioned.
A new close method is used to deallocate open handles.
Issue #1751
Issue #1891
This patch changes the top-level directory layout as a preparatory
step for improving the tools for managing 3rd-party source codes.
The rationale is described in the issue referenced below.
Issue #1082