Commit Graph

34 Commits

Author SHA1 Message Date
Martin Stein
d9b5e4ae8d libc: warn on missing std*="" or <fd path=""> file
The libc kernel used to silently go on if one of the files given through
stdin/stdout/stderr or <fd path=""> was missing (with possibly vital
functionality for the component not working). A pointer to the presumably
simple configuration issue of the underlying scenario was not given to the
user.

With this commit, the libc kernel prints a descriptive warning before
proceeding with the invalid file descriptor

Fixes #4218
2022-09-19 14:00:34 +02:00
Martin Stein
5e9e003bb0 libc: warn on missing std*="" or <fd path=""> dirs
The libc kernel used to end up in an uncaught exception if one of the
directories in the paths given through stdin/stdout/stderr or <fd path=""> was
missing. The resulting error didn't point the user to the presumably simple
configuration issue of his scenario in any way and killed the affected
component.

With this commit, the libc kernel prints a descriptive warning instead and
simply continues to run the component with the corresponding file descriptor
missing. At least in case of stdin/stdout/stderr, the libc deals gracefully
with this approach.

Ref #4218
2022-09-19 14:00:34 +02:00
Johannes Schlatow
7d143087c9 xml_node: change with_sub_node signature
The `with_sub_node` method is renamed to `with_optional_sub_node` to
better reflect that the non-existence of a sub node with the desired type is
ignored.
At the same time, the new `with_sub_node` now takes a second functor that is
called when no sub node of the desired type exists.

genodelabs/genode#4600
2022-09-19 14:00:33 +02:00
Norman Feske
16cf1f48d3 libc: make app stack size configurable
This patch changes the libc to query the stack size from the
config attribute <libc> <stack size=""/> </libc> for regular
components, not only cloned processes.
2022-05-25 12:19:32 +02:00
Norman Feske
c2efa5406e xml_node: support backslash as attribute value
XML allows attribute values like <node attr="\"/>. The XML parser
wrongly reflects this case as 'Invalid_syntax'. This behavior stems from
the implicit use of the 'end_of_quote' function, which considers the
sequence of '\"' as a quoted '"' rather than the end of a quoted string.

The patch solves this problem by making the 'end_of_quote' part of
the tokenizer's scanner policy.

The patch removes the 'end_of_quote' function from 'util/string.h'
because it is not universal, and to avoid the ambiguity with
'SCANNER_POLICY::end_of_quote'.

Fixes #4431
2022-02-21 15:44:22 +01:00
Alexander Boettcher
33a64f79dc libc: place pthreads round-robin
if the number of threads started exceed configured placement configuration

Issue #3967
2021-05-05 11:21:42 +02:00
Norman Feske
a99f6a81b6 libc: clone 'environ' pointer value after fork
The 'environ' pointer is a global variable that must be considered as
part of the application state. It must be copied from the parent to the
child process during fork. Otherwise, a child returning from fork is
unable to access environment variables before invoking execve. The
actual environment variables and their values are already captured
because they reside at the application heap, which is cloned from the
parent. So the copied 'environ' pointer refers to valid data.

Fixes #4015
2021-02-23 12:02:44 +01:00
Josef Söntgen
51a50ece60 libc: guard select call in socket_fs with monitor
Issue #3682.
2020-11-27 09:19:08 +01:00
Christian Prochaska
058f2e687c libc: make 'mmap()' address alignment configurable
With this commit, the alignment of anonymous 'mmap()' allocations can be
configured like this:

<config>
  <libc>
    <mmap align_log2="21"/>
  </libc>
</config>

Fixes #3907
2020-10-09 13:47:33 +02:00
Christian Helmuth
a0a112ffe7 libc: use monitor for fork
Issue #3874
2020-09-17 10:13:20 +02:00
Christian Helmuth
a891b3832c libc: use monitor for pthread join/cancel
Issue #3874
2020-09-17 10:13:20 +02:00
Norman Feske
e9a3f0f095 libc: use monitor for select
This patch simplifies the control flow within the libc kernel by
facilitating the monitor mechanism for the implementation of 'select'.

Issue #3874
2020-09-17 10:13:20 +02:00
Christian Helmuth
ab953a534c libc: remove residues of noux fork support 2020-09-09 16:57:34 +02:00
Christian Prochaska
9bc6b8be5a libc: handle 'MAP_SHARED' flag in 'mmap()'
Fixes #3857
2020-08-25 11:50:11 +02:00
Norman Feske
556a5c8086 libc: clean up 'clock_gettime' handling
This patch untangles the dependency of VFS operations that need RTC
information from the 'clock_gettime' libc function that must never be
called from the libc kernel context.

- The 'Rtc' class uses the VFS directly for reading the rtc file instead
  of relying on libc functions.

- The 'Rtc' instance has become part of the 'Kernel' instead of
  being construced as a side effect of the first call of
  'clock_gettime'.

- Changed 'Rtc::read' to return a timespec value, which has a higher
  precision than the formerly used time_t value.

- The 'Rtc::read' returns a value with the relative 'current_time'
  already applied. The former handling of subsequent rtc-value
  updates has been rewritten to become more logical.

- The 'Vfs_plugin' no longer calls 'clock_gettime' but the new
  kernel-level 'Current_real_time' interface.

Issue #2635
2020-08-25 11:50:10 +02:00
Norman Feske
852ab79359 Move atexit handling from base lib to libc
This patch untangles the interplay of the base library and the libc
during the exit handling.

- The CXA ABI for the atexit handling is now provided by the libc.
  For plain Genode components without libc dependency, __cxa_atexit
  is a no-op, which is consistent with Genode's notion of components.

- The 'abort' implementation of the base library no longer calls
  'genode_exit' but merely 'sleep_forever'. This way, the cxx library
  no longer depends on a 'genode_exit' implementation.

- The libc provides 'atexit' support by storing metadata on the
  libc kernel's heap now, thereby eliminating the former bounded
  maximum number of atexit handlers.

- Shared-library dtors are no longer called via the atexit mechanism
  by explicitly by the dynamic linker. This slightly changes the
  call order of destructors (adjustment of the ldso test). Functions
  marked as destructors are called after the atexit handlers now.

- The libc executes atexit handlers in the application context,
  which supports the I/O operations in those handles, in particular
  the closing of file descriptors.

Fixes #3851
2020-08-25 11:50:09 +02:00
Christian Helmuth
36b6ebc030 libc: process VFS operations in monitor
Fixes #2635
2020-08-25 11:49:44 +02:00
Christian Helmuth
9453287a6b libc: move current working directory into kernel 2020-08-25 11:49:43 +02:00
Alexander Boettcher
87b08d6c7f libc: support pthread placement configuration
Up to now all pthreads get placed on one CPU.

The patch adds support to evaluate a libc pthread configuration specifying
a placement strategy.

The default strategy is now to use all available CPUs as imposed by Genode's
affinity configuration for the pthread application.

The old behaviour, putting all pthreads on one single cpu can be still
configured by:

<libc>
 <pthread placement="single-cpu"/>
 ...
</libc>

Fixes #3775
2020-06-22 09:39:39 +02:00
Norman Feske
b078224753 Replace Genode::strncpy by Genode::copy_cstring
- Since Genode::strncpy is not 100% compatible with the POSIX
  strncpy function, better use a distinct name.

- Remove bogus return value from the function, easing the potential
  enforcement of mandatory return-value checks later.

Fixes #3752
2020-05-27 11:56:45 +02:00
Christian Helmuth
e52802162c libc: reimplement synchronization primitives
The new implementation relieves the main entrypoint from monitor jobs
for contended lock primitives and is based on custom applicant data
structures, per-lock resp. per-semaphore applicant lists, and a
libc-internal blockade with timeouts based on libc kernel primitives.
2020-02-27 14:47:00 +01:00
Christian Helmuth
ff5175ec76 libc: synchronization primitives based on monitor
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
2020-02-10 14:21:47 +01:00
Norman Feske
cd92b32622 libc: close all open FDs on exit
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
2019-12-19 17:00:48 +01:00
Norman Feske
b7fbe65ff2 libc: fork/execve improvements
- 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
2019-12-19 17:00:47 +01:00
Norman Feske
d4e0d2f578 libc: defer clone ack after FD initialization
Issue #3478
Issue #2303
2019-11-19 14:54:12 +01:00
Norman Feske
91412c6c52 libc: trigger SIGCHLD for when forked child exits 2019-11-19 14:45:39 +01:00
Norman Feske
c1012e6a45 libc: translate terminal user interrupts to SIGINT
Issue #3546
2019-11-19 14:45:38 +01:00
Norman Feske
636e0f6444 libc: cancel select when POSIX signal occurs
With this patch, Vim running via the 'bash.run' script becomes able to
adopt itself to changed window dimensions.

Issue #3544
2019-11-19 14:45:36 +01:00
Norman Feske
7b0771659e libc: trigger SIGWINCH by watching .terminal/info
Issue #3544
2019-11-19 14:43:43 +01:00
Josef Söntgen
e281174dae libc: bring back old 'poll()' emulation
Issue #3499
2019-11-19 14:23:55 +01:00
Norman Feske
418ac4c560 libc: remove global watch() function
This patch replaces the function with a 'Watch' interface to be
explicitly passed to the caller (currently only time.cc).

Issue #3497
2019-11-19 14:10:55 +01:00
Norman Feske
89a38723bd libc: reimplement passwd handling
- Eliminate call of global libc_config()
- Remove dynamic memory allocation, const cast
- Prepare for moving the state from compilation unit to header
- Fix run/libc_getpwent.run

Issue #3497
2019-11-19 14:10:55 +01:00
Norman Feske
648bcd1505 libc: unify use of namespaces
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
2019-11-19 14:10:55 +01:00
Norman Feske
bf92232698 libc: split task.cc into multiple files
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
2019-11-19 14:10:55 +01:00