The VFS server as reworked in issue #3547 responds to such an attempt
with a failure as acknowledgement, triggering the client-side error
"Error: packet operation=2 failed" at noux.
This patch prevents the driver from translating Insufficient_ram_quota
and Insufficient_cap_quota exceptions to Service_denied exceptions at
session-creation time. This enables the client to respond to such a
condition by retrying the session creation with increased session quota.
Add a new plugin for creating pipes between pairs of VFS handles. It is
intended to replace the libc_pipe plugin, one of the last remaining libc
plugins.
In contrast to the libc_pipe plugin, this plugin defers cross-handle
notification until I/O signal handling rather than block and unblock
readers using a semaphore. This is a performance regression in the case
of multiple threads blocking on a pipe, but shall be an intermediate
mechanism pending renovations within the libc VFS and threading layers.
As a side effect, threads blocked on a pipe might not be resumed until
the main thread suspends and dispatches I/O signals.
The "test-libc_pipe" test has been adjusted to use the VFS pipe plugin
and tests both local pipes and pipes hosted remotely in the VFS server.
Merge adaptations (such as EOF handling, adjustment to VFS/libc
interface changes) by Norman Feske.
Fix#2303
This patch reworks the VFS server to become easier to understand.
- The packet-stream handling is hidden from the node types.
- Introduced the notion of a "job" as an abstraction from the raw packet
stream.
- The processing of requests is split into three phases:
(1) accepting new jobs,
(2) the execution of jobs, and
(3) the delivery of acknowledgements.
- There is no longer a global fifo of pending nodes. Instead, each
session has a fifo of "active" nodes, which are nodes that wait
for the completion of jobs.
- The Io_node type no longer uses virtual functions as hooks for
the derrived classes. Instead, it provides a number of utility
functions.
- The control flow of the 'Io_progress_handler' is now the same as
for the session-local packet-stream handler.
- Removed dependency from 'file_system/node.h', which is a relic
from the ram_fs.
While reworking the code, the following semantic changes were made
additionally.
- The handling of SEEK_TAIL no longer overwrites the file content at the
end of the file.
- Removed diagnostic message at session-creation time.
- Write loop for continuous files
Issue #3547
Issue #2303
This patch reduces the debug noise for the prominent case of executing
bash with coreutils. Without it, the forked process will always ask for
more RAM immediately when starting up.
This change allows for the conversion of directory entries in place
(i.e., in the VFS server) and anticipates the potential future merge of
both types into one.
Issue #3547
This patch improves the libc's write operation to iterate on partial
writes to continuous files until the original write count is reached.
The split of large write operations into small partial writes as
dictated by the VFS infrastructure (e.g., constained by I/O buffer
sizes) becomes invisible to the libc-using application.
Issue #3507
Issue #2303
Make sure that at least entry is present in the .dynamic section, so the
PT_DYNAMIC segment points to something valid in case there are no
dynamic symbols.
issue #3537
This patch adds the ability to call 'kill' with the own PID to trigger
the execution of the handler of the specified POSIX signal. This is used
by 'bash', e.g., when cancelling the input of a command via control-c.
Related to issue #3546
This patch equips the VFS terminal file system with the ability to
detect user interrupts in the incoming data stream, and propagate this
information via the new pseudo file '.terminal/interrupts'. Each time,
the user presses control-c in the terminal, the value stored in this
pseudo file is increased. Thereby, a VFS client can watch this file to
get notified about the occurrences of user interrupts.
Fixes#3546
The scratch buffer is now allocated from the heap and is shared
between the test as they are executed in a serial fashion. This
change saves memory as the test are constructed at start-up.
Fixes#3539.
This patch adds support for watch notifications for the
'Readonly_value_file_system', which is often used by VFS plugins to
implement pseudo files. It thereby enables VFS clients to respond to
VFS-plugin events (think of terminal resize) dynamically.
Fixes#3523
