These functions don't really abort() on OOM. The fix was merged
upstream, but not in the minimal version we require. Provide our
own implementation which can be removed once we bump the minimal
version.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

Delete the macro to prevent its usage in new code.

The GLib version should be used instead:
    p = g_steal_pointer(&ptr);
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Remove the macro definition to prevent its usage in new code.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Prefer the GLib version of the macro.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Also define the macro for building with GLib older than 2.60
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Define the macro for older GLib versions.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Add the main glib.h to internal.h so that all common code can use it.

Historically glib allowed applications to register an alternative
memory allocator, so mixing g_malloc/g_free with malloc/free was not
safe.

This was feature was dropped in 2.46.0 with:

      commit 3be6ed60aa58095691bd697344765e715a327fc1
      Author: Alexander Larsson <alexl@redhat.com>
      Date:   Sat Jun 27 18:38:42 2015 +0200

        Deprecate and drop support for memory vtables

Applications are still encourged to match g_malloc/g_free, but it is no
longer a mandatory requirement for correctness, just stylistic. This is
explicitly clarified in

    commit 1f24b36607bf708f037396014b2cdbc08d67b275
    Author: Daniel P. Berrangé <berrange@redhat.com>
    Date:   Thu Sep 5 14:37:54 2019 +0100

        gmem: clarify that g_malloc always uses the system allocator

Applications can still use custom allocators in general, but they must
do this by linking to a library that replaces the core malloc/free
implemenentation entirely, instead of via a glib specific call.

This means that libvirt does not need to be concerned about use of
g_malloc/g_free causing an ABI change in the public libary, and can
avoid memory copying when talking to external libraries.

This patch probes for glib, which provides the foundation layer with
a collection of data structures, helper APIs, and platform portability
logic.

Later patches will introduce linkage to gobject which provides the
object type system, built on glib, and gio which providing objects
for various interesting tasks, most notably including DBus client
and server support and portable sockets APIs, but much more too.
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

We don't need to care about very old GCC versions, so implementing the
ignore_value macro directly is not a significant burden.
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

We're using gnulib to get ffs, ffsl, rotl32, count_one_bits,
and count_leading_zeros. Except for rotl32 they can all be
replaced with gcc/clangs builtins. rotl32 is a one-line
trivial function.
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

The previous bump to 4.4 was done in:

  commit 24241c23
  Author: Daniel P. Berrange <berrange@redhat.com>
  Date:   Wed Jul 5 10:35:32 2017 +0100

    Require use of GCC 4.4 or CLang compilers

with 4.4 picked due to RHEL-6. Since we dropped RHEL-6, the
next oldest distro is RHEL-7 (4.8.5), and thus we pick 4.8
as the new min.
Reviewed-by: NAndrea Bolognani <abologna@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Signed-off-by: NJonathon Jongsma <jjongsma@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NJán Tomko <jtomko@redhat.com>

With the introduction of more and more internal data types which support
VIR_AUTOPTR it's becoming common to see the following pattern:

  VIR_AUTOPTR(virSomething) some = NULL
  virSomethingPtr ret = NULL;

  ... (ret is not touched ) ...

  VIR_STEAL_PTR(ret, some);
  return ret;

This patch introduces a macro named VIR_RETURN_PTR which returns the
pointer directly without the need for an explicitly defined return
variable and use of VIR_STEAL_PTR. Internally obviously a temporary
pointer is created to allow setting the original pointer to NULL so that
the VIR_AUTOPTR function does not free the memory which we want to
actually return.

The name of the temporary variable is deliberately long and complex to
minimize the possibility of collision.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

This macro neither takes nor produces an empty string.
Remove it in favor of NULLSTR_MINUS.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NAndrea Bolognani <abologna@redhat.com>

NULLSTR_EMPTY, the quiet child,
NULLSTR_STAR, the famous one and
NULLSTR_MINUS, the grumpy one.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NAndrea Bolognani <abologna@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: NDaniel P. Berrangé <berrange@redhat.com>

This introduces a syntax-check script that validates header files use a
common layout:

  /*
   ...copyright header...
   */
  <one blank line>
  #ifndef SYMBOL
  # define SYMBOL
  ....content....
  #endif /* SYMBOL */

For any file ending priv.h, before the #ifndef, we will require a
guard to prevent bogus imports:

  #ifndef SYMBOL_ALLOW
  # error ....
  #endif /* SYMBOL_ALLOW */
  <one blank line>

The many mistakes this script identifies are then fixed.
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

It doesn't really make sense for us to have stdlib.h and string.h but
not stdio.h in the internal.h header.
Signed-off-by: NErik Skultety <eskultet@redhat.com>
Acked-by: NMichal Privoznik <mprivozn@redhat.com>

Historically we have relied on autopoint/gettextize to install a
standard po/Makefile.in.in. There is very limited scope for customizing
this and it also causes a bunch of extra stuff to be pulled into
configure.ac which potentially clashes with gnulib. Writing make rules
for po file management is no more difficult than any other rules libvirt
has, so stop using autopoint/gettextize.
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Simple macro to check the prefix of a string in a case-insensitive way.
Signed-off-by: NPino Toscano <ptoscano@redhat.com>

Right-aligning backslashes when defining macros or using complex
commands in Makefiles looks cute, but as soon as any changes is
required to the code you end up with either distractingly broken
alignment or unnecessarily big diffs where most of the changes
are just pushing all backslashes a few characters to one side.

Generated using

  $ git grep -El '[[:blank:]][[:blank:]]\\$' | \
    grep -E '*\.([chx]|am|mk)$$' | \
    while read f; do \
      sed -Ei 's/[[:blank:]]*[[:blank:]]\\$/ \\/g' "$f"; \
    done
Signed-off-by: NAndrea Bolognani <abologna@redhat.com>

This reverts commit e4b980c8.

When a binary links against a .a archive (as opposed to a shared library),
any symbols which are marked as 'weak' get silently dropped. As a result
when the binary later runs, those 'weak' functions have an address of
0x0 and thus crash when run.

This happened with virtlogd and virtlockd because they don't link to
libvirt.so, but instead just libvirt_util.a and libvirt_rpc.a. The
virRandomBits symbols was weak and so left out of the virtlogd &
virtlockd binaries, despite being required by virHashTable functions.

Various other binaries like libvirt_lxc, libvirt_iohelper, etc also
link directly to .a files instead of libvirt.so, so are potentially
at risk of dropping symbols leading to a later runtime crash.

This is normal linker behaviour because a weak symbol is not treated
as undefined, so nothing forces it to be pulled in from the .a You
have to force the linker to pull in weak symbols using -u$SYMNAME
which is not a practical approach.

This risk is silent bad linkage that affects runtime behaviour is
not acceptable for a fix that was merely trying to fix the test
suite. So stop using __weak__ again.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

This reverts commit b9473d8b.

The Win32 platform will fail to link if you use weak symbols
because it is incompatible with exporting symbols in a DLL:

Cannot export virRandomGenerateWWN: symbol wrong type (2 vs 3)

We only need weak symbols for our test suite to do LD_PRELOAD
and this doesn't work on Win32, so we can just drop the hack
for Win32
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Currently all mockable functions are annotated with the 'noinline'
attribute. This is insufficient to guarantee that a function can
be reliably mocked with an LD_PRELOAD. The C language spec allows
the compiler to assume there is only a single implementation of
each function. It can thus do things like propagating constant
return values into the caller at compile time, or creating
multiple specialized copies of the function body each optimized
for a different caller. To prevent these optimizations we must
also set the 'noclone' and 'weak' attributes.

This fixes the test suite when libvirt.so is built with CLang
with optimization enabled.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The TODO macro expands to an fprintf() call and is used in several
places in the Xen driver. Anything that wishes to print such debug
messages should use the logging macros. In this case though, all the
places in the Xen driver should have been raising a formal libvirt
error instead. Add proper error handling and delete the TODO macro
to prevent future misuse.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The HOST_NAME_MAX, INET_ADDRSTRLEN and VIR_LOOPBACK_IPV4_ADDR
constants are only used by a handful of files, so are better
kept in virsocketaddr.h or the source file that uses them.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

We only ever test libvirt with GCC or CLang which provides a
GCC compatible compilation environment. Between them, these
compilers cover every important operating system platform,
even Windows.

Mandate their use to make it explicit that we don't care about
compilers like Microsoft VCC or other UNIX vendor C compilers.

GCC 4.4 was picked as the baseline, since RHEL-6 ships 4.4.7
and that lets us remove a large set of checks. There is a slight
issue that CLang reports itself as GCC 4.2, so we must also check
if __clang__ is defined. We could check a particular CLang version
too, but that would require someone to figure out a suitable min
version which is fun because OS-X reports totally different CLang
version numbers from CLang builds on Linux/BSD
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Back in this commit:

  commit b436a8ae
  Author: Fabian Freyer <fabian.freyer@physik.tu-berlin.de>
  Date:   Thu Jun 9 00:50:35 2016 +0000

    gnulib: add getopt module

config-post.h was modified to define __GNUC_PREREQ, but the
original definition was never removed from internal.h, and
that is now dead code since config.h is always the first file
included.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Use a macro instead of hardcoding "127.0.0.1" throughout the
sources.

Currently, we don't assign any meaning to that. Our current view
on virStream is that it's merely a pipe. And pipes don't support
seeking.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

The debian etch distro was end-of-life a long time ago so we no
longer need the ULLONG_MAX hack. In any case gnulib now provides
an equivalent fix by default, and so our definition now triggers
syntax-check rule failure

src/internal.h:#    define ULLONG_MAX   ULONG_LONG_MAX
maint.mk: define the above via some gnulib .h file
maint.mk:843: recipe for target 'sc_prohibit_always-defined_macros' failed
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Apple have annotated all SASL functions as deprecated for
unknown reasons. Since they still work, lets just ignore
the warnings. If Apple finally delete the SASL functions
our configure check should already catch that
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

CLang's optimizer is more aggressive at inlining functions than
gcc and so will often inline functions that our tests want to
mock-override. This causes the test to fail in bizarre ways.

We don't want to disable inlining completely, but we must at
least prevent inlining of mocked functions. Fortunately there
is a 'noinline' attribute that lets us control this per function.

A syntax check rule is added that parses tests/*mock.c to extract
the list of functions that are mocked (restricted to names starting
with 'vir' prefix). It then checks that src/*.h header file to
ensure it has a 'ATTRIBUTE_NOINLINE' annotation. This should prevent
use from bit-rotting in future.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

In GCC 7 there is a new warning triggered when a switch
case has a conditional statement (eg if ... else...) and
some of the code paths fallthrough to the next switch
statement. e.g.

conf/domain_conf.c: In function 'virDomainChrEquals':
conf/domain_conf.c:14926:12: error: this statement may fall through [-Werror=implicit-fallthrough=]
         if (src->targetTypeAttr != tgt->targetTypeAttr)
            ^
conf/domain_conf.c:14928:5: note: here
     case VIR_DOMAIN_CHR_DEVICE_TYPE_CONSOLE:
     ^~~~
conf/domain_conf.c: In function 'virDomainChrDefFormat':
conf/domain_conf.c:22143:12: error: this statement may fall through [-Werror=implicit-fallthrough=]
         if (def->targetTypeAttr) {
            ^
conf/domain_conf.c:22151:5: note: here
     default:
     ^~~~~~~

GCC introduced a __attribute__((fallthrough)) to let you
indicate that this is intentionale behaviour rather than
a bug.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Our STREQ_NULLABLE and STRNEQ_NULLABLE macros are too
complicated. This was a result of some broken version of gcc.
However, that is long gone and therefore we can simplify the
macros.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

VIR_STEAL_PTR copies the pointer from the second argument into the
first argument and then sets the second to NULL.

fdstream.c: In function 'virFDStreamWrite':
fdstream.c:390:29: error: logical 'or' of equal expressions [-Werror=logical-op]
        if (errno == EAGAIN || errno == EWOULDBLOCK) {
                            ^~

Fedora rawhide now uses gcc 6.0 and there is a bug with -Wlogical-op
producing false warnings.

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69602

Use GCC pragma push/pop and ignore -Wlogical-op for GCC that supports
push/pop pragma and also has this bug.
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>