Extend the host OS checks to define an OS_WINDOWS automake conditional if
the host is MinGW-like. This will be useful for future Windows-specific
build tweaks.
[guillem@hadrons.org:
- Rename WINDOWS conditional to OS_WINDOWS. ]
Signed-off-by: Guillem Jover <guillem@hadrons.org>
This is a glibc-specific symbol that has no public declaration. But is
being used by the OpenBSD and this implementation as a hack to avoid
having to link against the pthread library. This interface is at least
included in LSB 5.0 [L], and using pthread_atfork() is otherwise
problematic anyway [P].
[L] <https://refspecs.linuxfoundation.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib---register-atfork.html>
[P] <http://austingroupbugs.net/view.php?id=851>
One problem is that we were using it whenever __GLIBC__ is defined,
which is supposed to be defined only on an actual glibc, but uClibc
defines that macro, but it does not provide the symbol on its noMMU
variant.
We add a new configure check that will try to link a program that uses
that symbol to make sure it is present.
Closes: !2
Reported-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Because we were assigning to another unused variable, when building the
check with optimizations enabled, which is the default when using gcc
as the compiler, the variable was being discarded. Instead pass it to
printf() so that it cannot do so.
In older glibc versions (< 2.17) clock_gettime() is in librt. Add a
check for this to avoid build breakage for programs/libraries that
use libbsd on such systems.
Based-on-patch-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Guillem Jover <guillem@hadrons.org>
Rework arc4random_stir() and arc4random_addrandom() code over the new
internal API, and documentation in the man page. Adapt the code to the
local build system.
Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=85827
In case the support is not available, just stop building the
libbsd-ctor.a library, which is a nice to have thing, but should not
have been a hard requirement from the start. This should allow to
build libbsd on non-glibc based systems using another libc.
This is a wrapper over the glibc fopencookie() function.
We diverge from the FreeBSD, OpenBSD and DragonFlyBSD declarations,
because seekfn() there wrongly uses fpos_t, assuming it's an integral
type, and any code using that on a system where fpos_t is a struct
(such as GNU-based systems or NetBSD) will fail to build. In which case,
as the code has to be modified anyway, we might just as well use the
correct declaration.
The automatic initialization cannot be part of the main shared library,
because there is no thread-safe way to change the environ global
variable. This is not a problem if the initializaion happens just at
program load time, but becomes one if the shared library is directly or
indirectly dlopen()ed during the execution of the program, which could
have either kept references to the old environ or could change it in
some other thread. This has been observed for example on systems using
Samba NSS modules.
To avoid any other possible fallout, the constructor is split into a
new static library that needs to be linked explicitly into programs
using setproctitle(). As an additional safety measure the pkg-config
linker flags will mark the program as not allowing to be dlopen()ed
so that we avoid the problem described above.
Reported-by: Jan Alexander Steffens (heftig) <jan.steffens@gmail.com>
Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=66679
The GNU .init_array support is an extension over the standard System V
ABI .init_array support, which passes the main() arguments to the init
function.
This support comes in three parts. First the dynamic linker (from glibc)
needs to support it. Then function pointers need to be placed in the
section, for example by using __attribute__((constructor)), that the
compiler (gcc or clang for example) might place in section .ctors and
the linker (from binutils) will move to .init_array on the output
object, or by placing them directly into .init_array by the compiler
when compiling. If this does not happen and the function pointers end
up in .ctors, then they will not get passed the main() arguments, which
we do really need in this case.
But this relies on recent binutils or gcc having native .init_array
support, and not having it disabled through --disable-initfini-array.
To guarantee we get the correct behaviour, let's just place the function
pointer in the .init_array section directly, so we only require a recent
enough glibc.
Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=65029
Make the 0.5 version the default, so that code wanting the actual
implemented version can get a proper versioned depdendency. For code
linked against the old version, make it available as an alias.
Use local getprogname()/setprogname() instead of reimplementing them
locally. Use clearenv() if available, not just on glibc. Use bool
instead of _Bool. Use paranthesis on sizeof. Fold the SPT_MIN macro
into spt_min(). Make spt_init() static. Avoid unnecessary gotos.
This centralizes the setting so there's no duplication anymore,
makes sure the user supplied variables are never overridden, and
are only set when using gcc.
Reported-by: Samuli Suominen <ssuominen@gentoo.org>
