The purpose of ERROR() macro in our NSS module is to print error
message provided as arguments followed by error string
corresponding to errno. Historically, we've used strerror_r() for
that (please note, we want our NSS module to be free of libvirt
internal functions, or glib even - hence, g_strerror() is off the
table).
Now strerror_r() is documented as:
Returns ... a pointer to a string that the function stores in
buf, or a pointer to some (immutable) static string (in which
case buf is unused).
Therefore, we can't rely the string being stored in the buf and
really need to store the retval and print that instead.
While touching this area, decrease the ebuf size, since its
current size (1KiB) is triggering our stack limit (2KiB) in some
cases.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Currently, we are mixing: #if HAVE_BLAH with #if WITH_BLAH.
Things got way better with Pavel's work on meson, but apparently,
mixing these two lead to confusing and easy to miss bugs (see
31fb929eca for instance). While we were forced to use HAVE_
prefix with autotools, we are free to chose our own prefix with
meson and since WITH_ prefix appears to be more popular let's use
it everywhere.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
When switching to meson, some of HAVE_* macros were renamed to
WITH_ because they did not reflect whether the build platform has
or doesn't have something, but whether we are building with some
functionality turned on or off. This is the case with
HAVE_BSD_NSS macro too. As a result, the NSS plugin built on BSD
did not expose nss_module_register() function which made the
plugin unusable:
https://www.redhat.com/archives/libvir-list/2020-September/msg00000.html
Fixes: c742687055
Reported-by: Roman Bogorodskiy <bogorodskiy@gmail.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Roman Bogorodskiy <bogorodskiy@gmail.com>
Reviewed-by: Jiri Denemark <jdenemar@redhat.com>
The NSS module has a compile time option which when enabled makes
ERROR() and DEBUG() print messages onto stderr. But now that the
module no longer links with libvirt, we need to include stdio.h
and define NULLSTR().
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
The conversion to drop gnulib in the previous patch:
commit 8242ce4f45
Author: Daniel P. Berrangé <berrange@redhat.com>
Date: Thu Aug 8 10:23:26 2019 +0100
tools: avoid accidentally using files from gnulib
Missed a few conversions needed for FreeBSD. In particular
netdb.h doesn't pull in sys/socket.h or netinet/in.h
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Use the plain libc APIs to avoid a dependancy on the main libvirt
code from the nss module.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The .macs file is currently loaded using the virMacMap class,
which in turn uses the virJSON parsing code. This pulls in a
heap of libvirt code (logging, hash tables, objects, etc) which
we do not wish to depend on.
This uses the yajl parser code directly, so the only dep is
yajl and plain libc functions.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Require that all headers are guarded by a symbol named
LIBVIRT_$FILENAME
where $FILENAME is the uppercased filename, with all characters
outside a-z changed into '_'.
Note we do not use a leading __ because that is technically a
namespace reserved for the toolchain.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
In many files there are header comments that contain an Author:
statement, supposedly reflecting who originally wrote the code.
In a large collaborative project like libvirt, any non-trivial
file will have been modified by a large number of different
contributors. IOW, the Author: comments are quickly out of date,
omitting people who have made significant contribitions.
In some places Author: lines have been added despite the person
merely being responsible for creating the file by moving existing
code out of another file. IOW, the Author: lines give an incorrect
record of authorship.
With this all in mind, the comments are useless as a means to identify
who to talk to about code in a particular file. Contributors will always
be better off using 'git log' and 'git blame' if they need to find the
author of a particular bit of code.
This commit thus deletes all Author: comments from the source and adds
a rule to prevent them reappearing.
The Copyright headers are similarly misleading and inaccurate, however,
we cannot delete these as they have legal meaning, despite being largely
inaccurate. In addition only the copyright holder is permitted to change
their respective copyright statement.
Reviewed-by: Erik Skultety <eskultet@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
So far the NSS module looks up only hostnames as provided by
guests themselves. However, there are some cases where this is
not enough: e.g. when there's a fresh new guest being installed
(with some generic hostname) say from a live ISO image; or some
(older) systems don't advertise their hostname in DHCP
transactions at all.
In cases like that it would be helpful if we translate domain
name as seen by libvirt too so that users can:
# virsh start $dom && ssh $dom
In order to achieve that new libvirt-guest module is introduced,
while older libvirt module maintains its current behaviour (that
is translating guest provided names into IP addresses).
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
The name of the exported functions for an NSS module is quite
fixed, it is derived from the module name:
_nss_$module_$function
Since we will create another NSS module with very similar
implementation we might as well generate the function names at
the compile time.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
* tools/nss/libvirt_nss.[ch]: add BSD-comptabile wrappers and
register via the nss_module_register() interface
* m4/virt-nss.m4: add checks if we're building NSS for FreeBSD
* tools/Makefile.am: handle target library name differences, as
Linux needs libnss_libvirt.so.2 and FreeBSD needs
nss_libvirt.so.1. Also, different syms files have to be used
as Linux needs to export all the methods while FreeBSD
only needs to have nss_module_register()
* tests/nsstest.c, tests/nssmock.c: s/__linux__/NSS/
* tests/nssmock.c: pass int instead of mode_t to va_arg() to please
gcc 4.8
* libvirt_nss_bsd.syms: FreeBSD syms file
This function is a different beast compared to previous ones.
But yet again, nothing surprising is happening here.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
The implementation is pretty straightforward. Moreover, because
of the nature of things, gethostbyname_r and gethostbyname2_r can
be implemented at the same time too.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Name Service Switch is a glibc feature responsible for many
things. Translating domain names into IP addresses and vice versa
is just one of them. However, currently it's the only
functionality that this commit is tickling. Well, in this commit
the plugin skeleton is introduced. Implementation to come in next
patches.
Because of the future testing, where the implementation is to be
linked with a test, this needs to go into static library. Linking
a program with an .so statically is not portable. Therefore a
dummy libnss_libvirt_impl library is being introduced too.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
