Commit Graph

24 Commits

Author SHA1 Message Date
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
Sebastian Sumpf
6dae147785 libc: limit fd id allocations to FD_SETSIZE
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
2019-12-19 17:00:47 +01:00
Josef Söntgen
180f9e6384 libc: handle modified files
Issue #1784.
2019-11-19 14:17:30 +01:00
Norman Feske
6894ced63b libc: execve
This patch implements 'execve' in Genode's libc.

The mechanism relies on the dynamic linker's ability to replace the
loaded binary while keeping crucial libraries - in particular the libc -
intact. The state outside the libc is wiped. For this reason, all libc
internal state needed beyond the 'execve' call must be allocated on a
heap separate from the application-owned malloc heap. E.g.,
libc-internal file-descriptor objects must not be allocated or refer to
any memory object allocated from the malloc heap.

Issue #3481
2019-08-28 14:19:45 +02:00
Norman Feske
bb5827b4e3 libc: fork, getpid, and wait4
This patch complements the C runtime with support for fork, getpid, and
wait4 (and its cousin 'waitpid').

Fixes #3478
2019-08-28 14:18:45 +02:00
Norman Feske
65f75589e9 libc: configurable initial FDs
The libc already supports the configuration of 'stdin', 'stdout', and
'stderr' using '<libc>' config attributes. This patch equips the libc
with the additional ability to pre-initialize any other file descriptor.
A file descriptor is configured as follows:

<config>
  ...
  <libc ...>
    <fd id="3" path="/dev/log" writeable="yes" readable="no" seek="10"/>
    ...
  </libc>
</config>

Furthermore, this patch moves the FD initialization code from the VFS
plugin to the libc kernel initialization because opening the FDs
depends on 'malloc' ('strdup'), which should not be used at early
'Libc::Kernel' initialization time.

Issue #3478
2019-08-28 14:18:44 +02:00
Norman Feske
6e38b53001 libc: use Id_space for FD allocator
This patch replaces the former use of an Allocator_avl with the Id_space
utility, which is safer to use and allows for the iteration of all
elements. The iteration over open file descriptors is needed for
implementing 'fork'.

Issue #3478
2019-08-28 14:18:44 +02:00
Emery Hemingway
863654d188 Libc: update port to Freebsd 12
Fix #3289
2019-05-27 14:46:53 +02:00
Emery Hemingway
8ca63d4a6e libc: reintegrate libc_resolv library
Remove getaddrinfo and freeaddrinfo from the Libc::Plugin and get rid of
the extra libc_resolv library. Remove getaddrinfo/freeaddrinfo symbol
hiding patch for FreeBSD sources. Remove libc_resolv from Makefiles and
run scenarios.

Fix #2273
2017-10-05 17:40:04 +02:00
Emery Hemingway
604ff9ca2c msync and Sytem V semaphore dummies
Ref #2467
2017-08-30 09:59:57 +02:00
Sebastian Sumpf
61ae2e5b80 libc-plugin: make fd allocator thread safe
issue #2488
2017-08-28 16:49:42 +02:00
Emery Hemingway
7ef8c81607 libc: socket fcntl flags inheritence
Set O_NONBLOCK on sockets from the fcntl syscall and propagate this flag
to socket_fs control files and sockets returned from accept.

Fix #2318
2017-03-24 16:19:55 +01:00
Norman Feske
29b8d609c9 Adjust file headers to refer to the AGPLv3 2017-02-28 12:59:29 +01:00
Josef Söntgen
a79f7d234b libc: remove global env from fd_alloc
Issue #2280.
2017-02-28 12:59:27 +01:00
Martin Stein
06e605defa LibC VFS: Warn on possible FD path leaks 2017-02-28 12:59:19 +01:00
Sebastian Sumpf
643a09b518 libc: late intialization of plugins
- for-each plugin iterator
* Call 'init(Genode::env &)' for each plugin bofore 'Libc::construct' or
'main' is called
2017-02-23 14:54:46 +01:00
Norman Feske
e370e08e01 Define Genode::size_t as unsigned long
Fixes #2105
2016-10-21 12:39:29 +02:00
Norman Feske
17c79a9e23 base: avoid use of deprecated base/printf.h
Besides adapting the components to the use of base/log.h, the patch
cleans up a few base headers, i.e., it removes unused includes from
root/component.h, specifically base/heap.h and
ram_session/ram_session.h. Hence, components that relied on the implicit
inclusion of those headers have to manually include those headers now.

While adjusting the log messages, I repeatedly stumbled over the problem
that printing char * arguments is ambiguous. It is unclear whether to
print the argument as pointer or null-terminated string. To overcome
this problem, the patch introduces a new type 'Cstring' that allows the
caller to express that the argument should be handled as null-terminated
string. As a nice side effect, with this type in place, the optional len
argument of the 'String' class could be removed. Instead of supplying a
pair of (char const *, size_t), the constructor accepts a 'Cstring'.
This, in turn, clears the way let the 'String' constructor use the new
output mechanism to assemble a string from multiple arguments (and
thereby getting rid of snprintf within Genode in the near future).

To enforce the explicit resolution of the char * ambiguity, the 'char *'
overload of the 'print' function is marked as deleted.

Issue #1987
2016-08-29 17:27:10 +02:00
Christian Helmuth
bf5df7d88d libc: qualify Plugin_context as base class
...by defining a virtual destructor.
2016-04-25 10:48:02 +02:00
Emery Hemingway
5d434944eb libc: support access() in plugins
Fixes #1703
2015-09-30 12:20:38 +02:00
Norman Feske
e3be65833f vfs: decouple file-system factory from libc
This patch moves the VFS file-system factory to a separate vfs library
that is independent from libc. This enables libc-less Genode programs to
easily use the VFS infrastructure.

Fixes #1561
2015-06-09 11:00:10 +02:00
Josef Söntgen
2bf67136c6 libc: add support for external vfs file systems
These file systems are provided on-demand by loading a shared library
when the fstab node is traversed. By convention this library is named
after the file system it provides. For example a file system that
provides a 'random' file system node is called 'vfs_random.lib.so'. It
is still possible to give the the node another name in the vfs. The
following code snippts illustrates this matter:

! [...]
! <config>
!   <libc>
!     <vfs>
!       <dir name="dev"> <jitterentropy name="random"/> </dir>
!     </vfs>
!   </libc>
! </config>
! [...]

Here the jitterentropy file system, implemented in
'vfs_jitterentropy.lib.so' provides a file system node named 'random'
in the 'dev' directory. When traversing the vfs section the libc will
try to load 'vfs_jitterentropy.lib.so' but programs may access the
file system only via '/dev/random'.

Fixes #1240.
2014-08-22 16:16:41 +02:00
Norman Feske
ca971bbfd8 Move repositories to 'repos/' subdirectory
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
2014-05-14 16:08:00 +02:00