The libc monitor facility enables the execution of monitor jobs by the
main thread when the monitor pool was charged. In comparison to the
current suspend/resume_all mechanism the main thread iterates over all
job functions in contrast to waking up all threads to check their
conditions by themselves. Threads are only woken up if the completion
condition was met.
This commit is the result of a collaboration with Christian Prochaska.
Many thanks for your support, Christian.
Fixes#3550
sleep(), usleep(), and nanosleep() now return immediately on
zero-timeout. Also, non-zero timeouts sleep at least 1 ms (the current
minimal timeout in libc), which compensates rounding errors.
Issue #3550
If the suspend method for the main thread detects that the suspend
condition is false it must return the passed timeout value (not always
0). Otherwise, the caller may incorrectly assume the timeout expired.
Incoming ACK packets for sent data packets may be the only unblocker for
suspended write/send loops. This patch informs VFS users about I/O of
VFS handle on successfully sent packets.
Store errno in pthread objects, return member upon call to '__error()'.
This became necessary in order to make errno thread-safe.
Note, any call to libc code from a non-pthread (beside the first
entrypoint) is not supported.
issue #3568
This is important to issue sync requests for written-to files.
As the closing must be performed by an atexit handler, it happens at a
time _after_ libc plugins are destructed. Consequently an FD allocated
by such a plugin results in a close error, which in turn, does not
destruct the FD. We ultimatedly end up in an infinte loop of
re-attempting the close. For this reason, the patch changes 'close' to
be robust against this special case.
This is generally not a problem because libc plugins are phased out.
However, at present, the libc_noux plugin is still important. With the
changed 'close' in place, there occurred an error message "Error: close:
close not implemented" at the exit of each noux program. This patch
removes the error printing from the libc plugin mechansim to avoid this
noise. The error messages are not important anyway because the
deprecation of the libc plugin interface.
Issue #3578
The getpeername function is provided only by the socket fs.
In the case where the socket fs is not configured, return an appropriate
errno instead probing for a libc plugin (there is none).
Issue #3578
- Close FDs marked with the close-on-execve flag
(needed for 'make', which sets the flag for the pipe-in
FD of forked children)
- Update binary name on execve to use as ROM for subsequent fork
- Enable vfork as an alias for fork (needed by make)
- Purge line buffers for output streams during execve because they
may be allocated at the allocation heap, which does not survive
the execve call.
- Consider short-lived processes that may exit while the parent still
blocks in the fork call.
With these changes, the website generator of genodians.org works without
the need for the Noux runtime.
Issue #3578
fd > FD_SETSIZE cannot use 'select' or 'poll' within our libc.
Therefore, we added a bit allocator in order to allocate fd < FD_SETSIZE
(1024).
fixes#3568
'dlopen' causes the ldso to open ROM connections, right now we only
support single file names for these ROM not paths. Therefore, we extract
the file name from path within libc's 'dlopen'
fixes#3551
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 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 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
