Unfortunately the data reported by pkg-config is not completely
accurate, so until the issue has been fixed in readline we need
to work around it in libvirt.
The good news is that we only need the fix to land in FreeBSD
ports and macOS homebrew before we can drop the kludge, so
we're talking months rather than years.
Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
With the 7.0 release, readline has finally started shipping
pkg-config support in the form of a readline.pc file.
Unfortunately, most downstreams have yet to catch up with this
change: among Linux distributions in particular, Fedora Rawhide
seems to be the only one installing it at the moment.
Non-Linux operating systems have been faring much better in
this regard: both FreeBSD (through ports) and macOS (through
homebrew) include pkg-config support in their readline package.
This is great news for us, since those are the platforms where
pkg-config is more useful on account of them installing headers
and libraries outside of the respective default search paths.
Our implementation checks whether readline is registered as a
pkg-config package, and if so obtains CFLAGS and LIBS using the
tool; if not, we just keep using the existing logic.
This commit is best viewed with 'git show -w'.
Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
The first implementation of this logic was introduced with
commit 2ec759fc58 all the way back in 2007; looking at the
build logs from our CI environment, however, it's apparent
that none of the platforms we currently target are actually
using it, so we can assume whatever issue it was working
around has been fixed at some point in the last 12 years.
Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
The current code is a bit awkward, and we're going to need
to share it later anyway. We can drop the call to AC_SUBST()
while we're at it, since LIBVIRT_CHECK_LIB() already marks
READLINE_CFLAGS for substitution.
The new code goes to some extra length to avoid setting
-D_FUNCTION_DEF twice: this is mostly for cosmetic reasons,
and it's necessary because LIBVIRT_CHECK_READLINE() is called
twice: once on its own, and then once more as part of
LIBVIRT_CHECK_BASH_COMPLETION().
Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
The check was added in 74416b1d48 without offering any
explanation outside of the commit message. Introduce a comment
to make digging through the git history unnecessary.
Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Apparently we can't assume that people run readline recent enough
to have rl_completion_quote_character (added in readline-5.0
released in 2011). However, we can't compile without it. So if
not present, disable readline.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
When building with clang 4.0.0, virsh build fails like this:
gmake[3]: Entering directory '/usr/home/novel/code/libvirt/tools'
CC virsh-virsh.o
In file included from virsh.c:45:
In file included from /usr/local/include/readline/readline.h:31:
/usr/local/include/readline/rltypedefs.h:35:22: error: this function declaration is not a prototype [-Werror,-Wstrict-prototypes]
typedef int Function () __attribute__ ((deprecated));
^
void
/usr/local/include/readline/rltypedefs.h:36:24: error: this function declaration is not a prototype [-Werror,-Wstrict-prototypes]
typedef void VFunction () __attribute__ ((deprecated));
^
void
/usr/local/include/readline/rltypedefs.h:37:26: error: this function declaration is not a prototype [-Werror,-Wstrict-prototypes]
typedef char *CPFunction () __attribute__ ((deprecated));
^
void
/usr/local/include/readline/rltypedefs.h:38:28: error: this function declaration is not a prototype [-Werror,-Wstrict-prototypes]
typedef char **CPPFunction () __attribute__ ((deprecated));
^
void
In file included from virsh.c:45:
/usr/local/include/readline/readline.h:385:23: error: this function declaration is not a prototype [-Werror,-Wstrict-prototypes]
extern int rl_message ();
^
void
5 errors generated.
gmake[3]: *** [Makefile:2823: virsh-virsh.o] Error 1
Fix that by adding -D_FUNCTION_DEF to READLINE_CFLAGS to fix *Function
related warnings and add a check for stdarg.h so we have HAVE_STDARG_H
defined that's needed by the readline headers to use proper rl_message
declaration.
Bug report on the readline mailing list:
http://lists.gnu.org/archive/html/bug-readline/2017-05/msg00004.html
LIBVIRT_ARG_WITH_ALT is more generic than LIBVIRT_ARG_WITH, which
is tailored at switching features on and off.
Rename the macros according to their intended purpose, and add
some documentation to help developers pick between the two.
Usage of AC_REQUIRE will mess with order how LIBVIRT_CHECK_* macros
are composed into configure.ac. This ensures that the output of
configure --help is properly ordered and grouped into sections.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Following patch will update LIBVIRT_CHECK_(LIB|LIB_ALT|PKG) macros in
a way that you will be able to call a another macro as a fallback if
the first one fails. To allow that, we need to move the
LIBVIRT_ARG_WITH out of those macro to not have two or more same lines
in output of "configure --help".
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Make it much easier to test a configuration built without readline
support, by reusing our existing library probe machinery. It gets
a bit tricky with readline, which does not provide a pkg-config
snippet, and which on some platforms requires one of several
terminal libraries as a prerequiste, but the end result should be
the same default behavior but now with the option to disable things.
* m4/virt-readline.m4 (LIBVIRT_CHECK_READLINE): Simplify by using
LIBVIRT_CHECK_LIB.
* tools/virsh.c: Convert USE_READLINE to WITH_READLINE.
Signed-off-by: Eric Blake <eblake@redhat.com>
A future patch will allow disabling readline; doing this in an
isolated file instead of configure.ac will make the task easier.
* configure.ac: Move readline code...
* m4/virt-readline.m4: ...here.
Signed-off-by: Eric Blake <eblake@redhat.com>
