VIR_AUTODISPOSE_STR is similar to VIR_AUTOFREE(char *) but uses
virDispose for clearing of the stored string.

This patch also refactors VIR_DISPOSE to use the new helper which is
used for the new macro.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Document that @func must take pointer to @type.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

We'd free only the first element of the vector leaking the rest.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NErik Skultety <eskultet@redhat.com>

The new utility macros are useful for variables we put on the stack but
require some cleanup. The most prominent of those is virBuffer which is
used almost exclusively in that way.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

Add helper for utilizing __attribute__(cleanup())) for unref-ing
instances of sublasses of virObject.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NErik Skultety <eskultet@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>

Signed-off-by: NYuri Chornoivan <yurchor@ukr.net>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NJán Tomko <jtomko@redhat.com>

New macros are introduced which help in adding GNU C's cleanup
attribute to variable declarations. Variables declared with these
macros will have their allocated memory freed automatically when
they go out of scope.
Signed-off-by: NSukrit Bhatnagar <skrtbhtngr@gmail.com>
Reviewed-by: NErik Skultety <eskultet@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>

Seems recent versions of Coverity have (mostly) resolved the issue using
ternary operations in VIR_FREE (and now VIR_DISPOSE*) macros.  So let's
just remove it and if necessary handle one off issues as the arise.

The INPLACE variants of the VIR_APPEND macros cannot fail and they are
inherently quiet.

For a few cases where we handle secret information it's good to clear
the buffers containing sensitive data before freeing them.

Introduce VIR_DISPOSE, VIR_DISPOSE_N and VIR_DISPOSE_STRING that allow
simple clearing fo the buffers holding sensitive information on cleanup
paths.

Now that we've finally fixed all the violators, it's time to
enforce that any pointer to a const object is never freed (it
is aliasing some other memory, where the non-const original
should be freed instead).  Alas, the code still needs a normal
vs. Coverity version, but at least we are still guaranteeing
that the macro call evaluates its argument exactly once.

I verified that we still get the following compiler warnings,
which in turn halts the build thanks to -Werror on gcc (hmm,
gcc 4.8.3's placement of the ^ for ?: type mismatch is a bit
off, but that's not our problem):

    int oops1 = 0;
    VIR_FREE(oops1);
    const char *oops2 = NULL;
    VIR_FREE(oops2);
    struct blah { int dummy; } oops3;
    VIR_FREE(oops3);

util/virauthconfig.c:159:35: error: pointer/integer type mismatch in conditional expression [-Werror]
     VIR_FREE(oops1);
                                   ^
util/virauthconfig.c:161:5: error: passing argument 1 of 'virFree' discards 'const' qualifier from pointer target type [-Werror]
     VIR_FREE(oops2);
     ^
In file included from util/virauthconfig.c:28:0:
util/viralloc.h:79:6: note: expected 'void *' but argument is of type 'const void *'
 void virFree(void *ptrptr) ATTRIBUTE_NONNULL(1);
      ^
util/virauthconfig.c:163:35: error: type mismatch in conditional expression
     VIR_FREE(oops3);
                                   ^

* src/util/viralloc.h (VIR_FREE): No longer cast away const.
* src/xenapi/xenapi_utils.c (xenSessionFree): Work around bogus
header.
Signed-off-by: NEric Blake <eblake@redhat.com>

Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

In fact, the suffix should be _QUIET not _QUIT to stress the
fact, that no OOM error is reported on error.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Similarly to VIR_STRDUP, we want the OOM error to be reported in
VIR_ALLOC and friends.

VIR_APPEND_ELEMENT(array, size, elem) was not safe if the expression
for 'size' had side effects.  While no one in the current code base
was trying to pass side effects, we might as well be robust and
explicitly document our intentions.

* src/util/viralloc.c (virInsertElementsN): Add special case.
* src/util/viralloc.h (VIR_APPEND_ELEMENT): Use it.
(VIR_ALLOC, VIR_ALLOC_N, VIR_REALLOC_N, VIR_EXPAND_N)
(VIR_RESIZE_N, VIR_SHRINK_N, VIR_INSERT_ELEMENT)
(VIR_DELETE_ELEMENT, VIR_ALLOC_VAR, VIR_FREE): Document
which macros are safe in the presence of side effects.
* docs/hacking.html.in: Document this.
* HACKING: Regenerate.
Signed-off-by: NEric Blake <eblake@redhat.com>

If users build with --enable-test-oom configure option,
they get this error saying, virAllocTest* functions are
not defined within tests/testutils.c.

Make the same fix as in commit de53effe.

* src/util/viralloc.h (virDeleteElementsN): Cater to old glibc.

The Coverity static analyzer was generating many false positives for the
unary operation inside the VIR_FREE() definition as it was trying to evaluate
the else portion of the "?:" even though the if portion was (1).
Signed-off-by: NEric Blake <eblake@redhat.com>

I noticed when writing the backend functions for virNetworkUpdate that
I was repeating the same sequence of memmove, VIR_REALLOC, nXXX-- (and
messed up the args to memmove at least once), and had seen the same
sequence in a lot of other places, so I decided to write a few
utility functions/macros - see the .h file for full documentation.

The intent is to reduce the number of lines of code, but more
importantly to eliminate the need to check the element size and
element count arithmetic every time we need to do this (I *always*
make at least one mistake.)

VIR_INSERT_ELEMENT: insert one element at an arbitrary index within an
  array of objects. The size of each object is determined
  automatically by the macro using sizeof(*array). The new element's
  contents are copied into the inserted space, then the original copy
  of contents are 0'ed out (if everything else was
  successful). Compile-time assignment and size compatibility between
  the array and the new element is guaranteed (see explanation below
  [*])

VIR_INSERT_ELEMENT_COPY: identical to VIR_INSERT_ELEMENT, except that
  the original contents of newelem are not cleared to 0 (i.e. a copy
  is made).

VIR_APPEND_ELEMENT: This is just a special case of VIR_INSERT_ELEMENT
  that "inserts" one past the current last element.

VIR_APPEND_ELEMENT_COPY: identical to VIR_APPEND_ELEMENT, except that
  the original contents of newelem are not cleared to 0 (i.e. a copy
  is made).

VIR_DELETE_ELEMENT: delete one element at an arbitrary index within an
  array of objects. It's assumed that the element being deleted is
  already saved elsewhere (or cleared, if that's what is appropriate).

All five of these macros have an _INPLACE variant, which skips the
memory re-allocation of the array, assuming that the caller has
already done it (when inserting) or will do it later (when deleting).

Note that VIR_DELETE_ELEMENT* can return a failure, but only if an
invalid index is given (index + amount to delete is > current array
size), so in most cases you can safely ignore the return (that's why
the helper function virDeleteElementsN isn't declared with
ATTRIBUTE_RETURN_CHECK). A warning is logged if this ever happens,
since it is surely a coding error.

[*] One initial problem with the INSERT and APPEND macros was that,
due to both the array pointer and newelem pointer being cast to void*
when passing to virInsertElementsN(), any chance of type-checking was
lost. If we were going to move in newelem with a memmove anyway, we
would be no worse off for this. However, most current open-coded
insert/append operations use direct struct assignment to move the new
element into place (or just populate the new element directly) - thus
use of the new macros would open a possibility for new usage errors
that didn't exist before (e.g. accidentally sending &newelemptr rather
than newelemptr - I actually did this quite a lot in my test
conversions of existing code).

But thanks to Eric Blake's clever thinking, I was able to modify the
INSERT and APPEND macros so that they *do* check for both assignment
and size compatibility of *ptr (an element in the array) and newelem
(the element being copied into the new position of the array). This is
done via clever use of the C89-guaranteed fact that the sizeof()
operator must have *no* side effects (so an assignment inside sizeof()
is checked for validity, but not actually evaluated), and the fact
that virInsertElementsN has a "# of new elements" argument that we
want to always be 1.

https://www.gnu.org/licenses/gpl-howto.html recommends that
the 'If not, see <url>.' phrase be a separate sentence.

* tests/securityselinuxhelper.c: Remove doubled line.
* tests/securityselinuxtest.c: Likewise.
* globally: s/;  If/.  If/

Per the FSF address could be changed from time to time, and GNU
recommends the following now: (http://www.gnu.org/licenses/gpl-howto.html)

  You should have received a copy of the GNU General Public License
  along with Foobar.  If not, see <http://www.gnu.org/licenses/>.

This patch removes the explicit FSF address, and uses above instead
(of course, with inserting 'Lesser' before 'General').

Except a bunch of files for security driver, all others are changed
automatically, the copyright for securify files are not complete,
that's why to do it manually:

  src/security/security_selinux.h
  src/security/security_driver.h
  src/security/security_selinux.c
  src/security/security_apparmor.h
  src/security/security_apparmor.c
  src/security/security_driver.c

The code is splattered with a mix of

  sizeof foo
  sizeof (foo)
  sizeof(foo)

Standardize on sizeof(foo) and add a syntax check rule to
enforce it
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

We can exploit the fact that gcc warns about int-to-pointer conversion
in ternary cond?(void*):(int) in order to prevent future mistakes of
calling VIR_FREE on a scalar lvalue.  For example, between commits
158ba873 and 802e2df9, we would have had this warning:

cc1: warnings being treated as errors
remote.c: In function 'remoteDispatchListNetworks':
remote.c:3684:70: error: pointer/integer type mismatch in conditional expression

There are still a number of places that malloc into a const char*;
while it would probably be worth scrubbing them to use char*
instead, that is a separate patch, so we have to cast away const
in VIR_FREE for now.

* src/util/memory.h (VIR_FREE): Make gcc warn about integers.
Iteratively developed from a patch by Christophe Fergeau.

When compiling libvirt with GCC 3.4.6 the following warning is being triggered quite a lot:

util/memory.h:60: warning: declaration of 'remove' shadows a global declaration
/usr/include/stdio.h:175: warning: shadowed declaration is here

Fix this by renaming the parameter to 'toremove'.

* src/util/memory.h (VIR_RESIZE_N): New macro.
* src/util/memory.c (virResizeN): New function.
* src/libvirt_private.syms: Export new helper.
* docs/hacking.html.in: Document it.
* HACKING: Regenerate.

* src/util/memory.h (VIR_REALLOC_N): Update docs.
(VIR_EXPAND_N, VIR_SHRINK_N): New macros.
(virAlloc, virAllocN, virReallocN, virAllocVar, virFree): Add some
gcc attributes.
* src/util/memory.c (virExpandN, virShrinkN): New functions.
(virReallocN): Update docs.
* src/libvirt_private.syms: Export new helpers.
* docs/hacking.html.in: Prefer newer interfaces over
VIR_REALLOC_N, since uninitialized memory can bite us.
* HACKING: Regenerate.

Regression introduced in commit 62170b99.

* src/util/memory.h: Placate cppi, and fit 80 columns.

* This patch implements a memory allocator to obtain memory for
  structures whose last member is a variable length array.  C99 refers
  to these variable length objects as structs containing flexible
  array members.
* Fixed macro parentheses per Eric Blake

* global: patch created by running:
for f in $(git ls-files '*.[ch]') ; do
    cppi $f > $f.t && mv $f.t $f
done

* src/bridge.c, src/bridge.h, src/buf.c, src/buf.h, src/cgroup.c,
  src/cgroup.h, src/conf.c, src/conf.h, src/event.c, src/event.h,
  src/hash.c, src/hash.h, src/hostusb.c, src/hostusb.h,
  src/iptables.c, src/iptables.h, src/logging.c, src/logging.h,
  src/memory.c, src/memory.h, src/pci.c, src/pci.h, src/qparams.c,
  src/qparams.h, src/stats_linux.c, src/stats_linux.h,
  src/threads-pthread.c, src/threads-pthread.h, src/threads-win32.c,
  src/threads-win32.h, src/threads.c, src/threads.h, src/util.c,
  src/util.h, src/uuid.c, src/uuid.h, src/virterror.c,
  src/virterror_internal.h, src/xml.c, src/xml.h: Move all files
  into src/util/
* daemon/Makefile.am: Add -Isrc/util/ to build flags
* src/Makefile.am: Add -Isrc/util/ to build flags and update for
  moved files
* src/libvirt_private.syms: Export cgroup APIs since they're now
  in util rather than linking directly to drivers
* src/xen/xs_internal.c: Disable bogus virEventRemoveHandle call
  when built under PROXY
* proxy/Makefile.am: Update for changed file locations. Remove
  bogus build of event.c
* tools/Makefile.am, tests/Makefile.am: Add -Isrc/util/ to build flags