On non-glibc based systems we cannot unconditionally use the
__GLIBC_PREREQ macro as it gets expanded before evaluation. Instead,
if it is undefined, define it to 0.
We should also always declare these functions on non-glibc based
systems. And on systems with a new enough glibc, which provides these
functions, we should still provide the declarations if _GNU_SOURCE
is *not* defined.
Reported-by: Jörg Krause <joerg.krause@embedded.rocks>
This is a non-portable header, and we cannot expect it to be provided by
the system libc (e.g. musl). We just need and rely on declaration that
we have defined ourselves in our own <bsd/sys/cdefs.h>. So we switch to
only ever assume that.
Fixes: https://bugs.freedesktop.org/105281
We mention that these are now superseded by the glibc implementations,
make the headers cope with already declared functions on glibc-based
systems, and document this in the man pages.
Some libc libraries do not have an <a.out.h> header. And a.out as an
executable format is very much obsolete on pretty much all currently
supported systems, even if they might still support loading such
objects.
Remove the a.out support to increase portability.
Some systems do not have these types available, and they are simply
convenience aliases. Instead use the expanded versions which are more
portable.
Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=101192
Although the current implementation in libbsd is probably one of the
safest ones around, it still poses some problems when used with many
file streams. This function has now a replacement, that is both more
standard and portable. Ask users to switch to getline(3) instead.
These two functions accept no arguments. The prototypes should reflect
this. This change lets the compiler warn about certain (admittedly
silly) mistakes.
Signed-off-by: Guillem Jover <guillem@hadrons.org>
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 glibc headers use selective inclusions through the __need_NAME
mechanism to avoid circular dependencies.
The problem is that if we are being overlaid, and have been requested
a partial inclusion, when we pass control to the system header, then
we might miss definitions needed by our own header, resulting in build
failures.
Workaround that by catching current partial requests, and skip the
current inclusion.
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
Taken from NetBSD.
[guillem@hadrons.org:
- Import from NetBSD instead of FreeBSD to get a 3-clause BSD license,
instead of a 4-clause one.
- Define compatibility macros.
- Change library from libc to libbsd and header in man page.
- Add copyright information to COPYING.
- Add symbol to map file. ]
Signed-off-by: Guillem Jover <guillem@hadrons.org>
Glibc tends to include standard headers with special definitions
that make few declarations or macros visible, this stomps over the
overlay #include_next <> logic.
Based-on-patch-by: Robert Millan <rmh@debian.org>
