add a wrapper for it in libc and rework the code in libthr, the
system call still can return EINTR, we keep this feature.
Discussed on: thread
Reviewed by: jilles
objects inside one ELF section, which prevents the creation of a ELF
section with mixed data types. For example, gcc LTO use libelf to
create a .gnu_lto_XXX section that contains integers and a string
table, which doesn't work with our libelf implementation.
The changes made in this commit include:
* Allow Elf_Data type to be different than section type.
* Relax Elf_Data alignment check.
* Align each Elf_Data by their own alignment instead of section alignment.
MFC after: 1 month
This adds a new "arrow" key "delete" corresponding to the kD termcap value.
It only works if that is a sequence such as "\033[3~"; if it is "\177", the
em-delete-prev-char or ed-delete-prev-char from the single-character
mappings remains. It turns out that most terminals (xterm and alikes,
syscons in xterm mode) produce "\033[3~" by default so <Delete> has the
expected effect.
This also means that things need to be considerably misconfigured for
<Backspace> to perform a <Delete> action.
This allows the nfs_getrootfh() function to return the
correct file handle size to pxe.c for pxeboot. It also
results in NFSv2 no longer being used by default anywhere
in FreeBSD. If built with OLD_NFSV2 defined, the old
code that predated this patch will be built and NFSv2
will be used.
Tested by: danny at cs.huji.ac.il
MFC after: 2 weeks
module private type, when private type mutex is locked/unlocked, thread
critical region is entered or leaved. These changes makes fork()
async-signal safe which required by POSIX. Note that user's atfork handler
still needs to be async-signal safe, but it is not problem of libthr, it
is user's responsiblity.
some cases we want to improve:
1) if a thread signal got a signal while in cancellation point,
it is possible the TDP_WAKEUP may be eaten by signal handler
if the handler called some interruptibly system calls.
2) In signal handler, we want to disable cancellation.
3) When thread holding some low level locks, it is better to
disable signal, those code need not to worry reentrancy,
sigprocmask system call is avoided because it is a bit expensive.
The signal handler wrapper works in this way:
1) libthr installs its signal handler if user code invokes sigaction
to install its handler, the user handler is recorded in internal
array.
2) when a signal is delivered, libthr's signal handler is invoke,
libthr checks if thread holds some low level lock or is in critical
region, if it is true, the signal is buffered, and all signals are
masked, once the thread leaves critical region, correct signal
mask is restored and buffered signal is processed.
3) before user signal handler is invoked, cancellation is temporarily
disabled, after user signal handler is returned, cancellation state
is restored, and pending cancellation is rescheduled.
their implementations aren't in the same files. Introduce LIBC_ARCH
and use that in preference to MACHINE_CPUARCH. Tested by amd64 and
powerpc64 builds (thanks nathanw@)
the separate .o for libc_pic.a. This prevents rtld from making the
symbol global.
Putting the stack_protector_compat.c into the public domain acknowledged
by kan.
Reviewed by: kan
MFC after: 2 weeks
atexit and __cxa_atexit handlers that are either installed by unloaded
dso, or points to the functions provided by the dso.
Use _rtld_addr_phdr to locate segment information from the address of
private variable belonging to the dso, supplied by crtstuff.c. Provide
utility function __elf_phdr_match_addr to do the match of address against
dso executable segment.
Call back into libthr from __cxa_finalize using weak
__pthread_cxa_finalize symbol to remove any atfork handler which
function points into unloaded object.
The rtld needs private __pthread_cxa_finalize symbol to not require
resolution of the weak undefined symbol at initialization time. This
cannot work, since rtld is relocated before sym_zero is set up.
Idea by: kan
Reviewed by: kan (previous version)
MFC after: 3 weeks
CLANG_PREFIX macro. This changes the default header search path when we
are building clang as part of cross-tools.
Submitted by: Dimitry Andric <dimitry at andric.com>
Reviewed by: freebsd-current
which does not know what is the state of interrupted system call, for
example, open() system call opened a file and the thread is still cancelled,
result is descriptor leak, there are other problems which can cause resource
leak or undeterminable side effect when a thread is cancelled. However, this
is no longer true in new implementation.
In defering mode, a thread is canceled if cancellation request is pending and
later the thread enters a cancellation point, otherwise, a later
pthread_cancel() just causes SIGCANCEL to be sent to the target thread, and
causes target thread to abort system call, userland code in libthr then checks
cancellation state, and cancels the thread if needed. For example, the
cancellation point open(), the thread may be canceled at start,
but later, if it opened a file descriptor, it is not canceled, this avoids
file handle leak. Another example is read(), a thread may be canceled at start
of the function, but later, if it read some bytes from a socket, the thread
is not canceled, the caller then can decide if it should still enable cancelling
or disable it and continue reading data until it thinks it has read all
bytes of a packet, and keeps a protocol stream in health state, if user ignores
partly reading of a packet without disabling cancellation, then second iteration
of read loop cause the thread to be cancelled.
An exception is that the close() cancellation point always closes a file handle
despite whether the thread is cancelled or not.
The old mechanism is still kept, for a functions which is not so easily to
fix a cancellation problem, the rough mechanism is used.
Reviewed by: kib@
number of host CPUs and osreldate.
This eliminates the last sysctl(2) calls from the dynamically linked image
startup.
No objections from: kan
Tested by: marius (sparc64)
MFC after: 1 month
