Commit 4dc04d3a added virNetlinkGetErrorCode, but forgot to provide
a fallback, which kills the build on mingw (among others):

  CCLD     libvirt.la
  Cannot export virNetlinkGetErrorCode: symbol not defined
  collect2: error: ld returned 1 exit status

* src/util/virnetlink.c (virNetlinkGetErrorCode): Provide fallback.
Signed-off-by: NEric Blake <eblake@redhat.com>

Add a default implementation of virNetDevSetIPv4Address using netlink
and libnl. This avoids requiring /usr/sbin/ip or /usr/sbin/ifconfig
external binaries.

C guarantees that static variables are zero-initialized.  Some older
compilers (and also gcc -fno-zero-initialized-in-bss) create larger
binaries if you explicitly zero-initialize a static variable.

* src/libvirt.c: Fix initialization.
* src/util/viralloc.c: Likewise.
* src/util/virdbus.c: Likewise.
* src/util/virevent.c: Likewise.
* src/util/virfile.c (safezero): Likewise.
* src/util/virlog.c: Likewise.
* src/util/virnetlink.c: Likewise.
* src/util/virthread.h (VIR_ONCE_GLOBAL_INIT): Likewise.
* src/util/virprocess.c (virProcessGetStartTime): Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

Inspired by a simpler patch from "Wangrui (K) <moon.wangrui@huawei.com>".

A submitted patch pointed out that virNetlinkCommand() was doing an
improper typecast of the return value from nl_recv() (int to
unsigned), causing it to miss error returns, and that even after
remedying that problem, virNetlinkCommand() was calling VIR_FREE() on
the pointer returned from nl_recv() (*resp) even if nl_recv() had
returned an error, and that in this case the pointer was verifiably
invalid, as it was pointing to memory that had been allocated by
libnl, but then freed prior to returning the error.

While reviewing this patch, I noticed several other problems with this
seemingly simple function (at least one of them as serious as the
problem being reported/fixed by the aforementioned patch), and decided
they all deserved to be fixed. Here is the list:

1) The return value from nl_recv() must be assigned to an int (rather
   than unsigned int) in order to detect failure.

2) When nl_recv() returns an error or 0, the contents of *resp is
   invalid, and should be simply set to 0, *not* VIR_FREE()'d.

3) When nl_recv() returns 0, errno is not set, so the logged error
   message should not reference errno (it *is* an error though).

4) The first error return from virNetlinkCommand returns -EINVAL,
   incorrectly implying that the caller can expect the return value to
   be of the "-errno" variety, which is not true in any other case.

5) The 2nd error return returns directly with garbage in *resp. While
   the caller should never use *resp in this case, it's still good
   practice to set it to NULL.

6) For the next 5 (!!) error conditions, *resp will contain garbage,
   and virNetlinkCommand() will goto it's cleanup code which will
   VIR_FREE(*resp), almost surely leading to a segfault.

In addition to fixing these 6 problems, this patch also makes the
following two changes to make the function conform more closely to the
style of other libvirt code:

1) Change the handling of return code from "named rc and defaulted to
0, but changed to -1 on error" to the more common "named ret and
defaulted to -1, but changed to 0 on success".

2) Rename the "error" label to "cleanup", since the code that follows
is executed in success cases as well as failure.

Any source file which calls the logging APIs now needs
to have a VIR_LOG_INIT("source.name") declaration at
the start of the file. This provides a static variable
of the virLogSource type.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Most of our code base uses space after comma but not before;
fix the remaining uses before adding a syntax check.

* src/util/vircommand.c: Consistently use commas.
* src/util/virlog.c: Likewise.
* src/util/virnetdevbandwidth.c: Likewise.
* src/util/virnetdevmacvlan.c: Likewise.
* src/util/virnetdevvportprofile.c: Likewise.
* src/util/virnetlink.c: Likewise.
* src/util/virpci.c: Likewise.
* src/util/virsysinfo.c: Likewise.
* src/util/virusb.c: Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

'const fooPtr' is the same as 'foo * const' (the pointer won't
change, but it's contents can).  But in general, if an interface
is trying to be const-correct, it should be using 'const foo *'
(the pointer is to data that can't be changed).

Fix up remaining offenders in src/util.

* src/util/virnetdev.h (virNetDevSetMAC)
(virNetDevReplaceMacAddress, virNetDevValidateConfig)
(virNetDevReplaceNetConfig): Use intended type.
* src/util/virnetdevbandwidth.h (virNetDevBandwidthCopy)
(virNetDevBandwidthPlug): Likewise.
* src/util/virnetdevmacvlan.h (virNetDevMacVLanCreate)
(virNetDevMacVLanCreateWithVPortProfile)
(virNetDevMacVLanDeleteWithVPortProfile)
(virNetDevMacVLanRestartWithVPortProfile)
(virNetDevMacVLanVPortProfileRegisterCallback): Likewise.
* src/util/virnetdevopenvswitch.h (virNetDevOpenvswitchAddPort):
Likewise.
* src/util/virnetdevtap.h (virNetDevTapCreateInBridgePort):
Likewise.
* src/util/virnetdevvlan.h (virNetDevVlanEqual)
(virNetDevVlanCopy): Likewise.
* src/util/virnetdevvportprofile.h
(virNetDevVPortProfileAssociate)
(virNetDevVPortProfileDisassociate): Likewise.
* src/util/virnetlink.h (virNetlinkEventRemoveCallback)
(virNetlinkEventAddClient, virNetlinkEventRemoveClient):
Likewise.
* src/util/virnetdev.c (virNetDevSetMAC)
(virNetDevReplaceMacAddress, virNetDevValidateConfig)
(virNetDevReplaceNetConfig): Fix fallout.
* src/util/virnetdevbandwidth.c (virNetDevBandwidthCopy)
(virNetDevBandwidthPlug): Likewise.
* src/util/virnetdevmacvlan.c (virNetDevMacVLanCreate)
(virNetDevMacVLanCreateWithVPortProfile)
(virNetDevMacVLanDeleteWithVPortProfile)
(virNetDevMacVLanRestartWithVPortProfile)
(virNetDevMacVLanVPortProfileRegisterCallback): Likewise.
* src/util/virnetdevopenvswitch.c (virNetDevOpenvswitchAddPort):
Likewise.
* src/util/virnetdevtap.c (virNetDevTapCreateInBridgePort):
Likewise.
* src/util/virnetdevvlan.c (virNetDevVlanEqual)
(virNetDevVlanCopy): Likewise.
* src/util/virnetdevvportprofile.c
(virNetDevVPortProfileAssociate)
(virNetDevVPortProfileDisassociate)
(virNetDevVPortProfileOpSetLink, virNetDevVPortProfileOpCommon)
(virNetDevVPortProfileOp8021Qbg, virNetDevVPortProfileOp8021Qbh):
Likewise.
* src/util/virnetlink.c (virNetlinkEventRemoveCallback)
(virNetlinkEventAddClient, virNetlinkEventRemoveClient):
Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

Convert the type of loop iterators named 'i', 'j', k',
'ii', 'jj', 'kk', to be 'size_t' instead of 'int' or
'unsigned int', also santizing 'ii', 'jj', 'kk' to use
the normal 'i', 'j', 'k' naming
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Use of the select() system call is inherantly dangerous since
applications will hit a buffer overrun if any FD number exceeds
the size of the select set size (typically 1024). Replace the
two uses of select() with poll() and use cfg.mk to ban any
future use of select().

NB: This changes the phyp driver so that it uses an infinite
timeout, instead of busy-waiting for 1ms at a time.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The second param of virNetlinkCommand should be
struct nlmsghdr, not unsigned char.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The virNetlinkCommand() method takes an 'unsigned char **'
parameter to be filled with the received netlink message.
The callers then immediately cast this to 'struct nlmsghdr',
triggering (bogus) warnings about increasing alignment
requirements

util/virnetdev.c: In function 'virNetDevLinkDump':
util/virnetdev.c:1300:12: warning: cast increases required alignment of target type [-Wcast-align]
     resp = (struct nlmsghdr *)*recvbuf;
            ^
util/virnetdev.c: In function 'virNetDevSetVfConfig':
util/virnetdev.c:1429:12: warning: cast increases required alignment of target type [-Wcast-align]
     resp = (struct nlmsghdr *)recvbuf;

Since all callers cast to 'struct nlmsghdr' we can avoid
the warning problem entirely by simply changing the
signature of virNetlinkCommand to return a 'struct nlmsghdr **'
instead of 'unsigned char **'. The way we do the cast inside
virNetlinkCommand does not have any alignment issues.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

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/

The virNetlinkEventAddClient / virNetlinkEventRemoveClient stub
impls had syntax errors in their parameter lists, using a ')'
after the second-to-last parameter instead of a ','
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

This patch introduce virNetlinkEventServiceStopAll() to stop
all the monitors to receive netlink messages for libvirtd.
Signed-off-by: NTang Chen <tangchen@cn.fujitsu.com>

This patch improve all the API in virnetlink.c to support
all kinds of netlink protocols, and make all netlink sockets
be able to join in groups.
Signed-off-by: NTang Chen <tangchen@cn.fujitsu.com>

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

Detected on Cygwin.  Broken in commit 387117ad.

* src/util/virnetdev.c (virNetDevValidateConfig)
(virNetDevReplaceNetConfig): Fix prototypes.
* src/util/virnetlink.c (virNetlinkEventAddClient)
(virNetlinkEventRemoveClient): Likewise.

This removes nearly all the per-file error reporting macros
from the code in src/util/. A few custom macros remain for the
case, where the file needs to report errors with a variety of
different codes or parameters
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Introduce new members in the virMacAddr 'class'
- virMacAddrSet: set virMacAddr from a virMacAddr
- virMacAddrSetRaw: setting virMacAddr from raw 6 byte MAC address buffer
- virMacAddrGetRaw: writing virMacAddr into raw 6 byte MAC address buffer
- virMacAddrCmp: comparing two virMacAddr
- virMacAddrCmpRaw: comparing a virMacAddr with a raw 6 byte MAC address buffer

then replace raw MAC addresses by replacing

- 'unsigned char *' with virMacAddrPtr
- 'unsigned char ... [VIR_MAC_BUFLEN]' with virMacAddr

and introduce usage of above functions where necessary.

To facilitate future troubleshooting add a bunch more debugging
statements into important startup parts of libvirt

The libvirt_private.syms file exports virNetlinkEventServiceLocalPid
so there needs to be a no-op stub for Win32 to avoid linker errors
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Commit 64297313 added three direct
references to nl_handle_* instead of using our aliases which hide
differences between libnl-3 and libnl-1.

This value will be needed to set the src_pid when sending netlink
messages to lldpad. It is part of the solution to:

  https://bugzilla.redhat.com/show_bug.cgi?id=816465

Note that libnl's port generation algorithm guarantees that the
nl_socket_get_local_port() will always be > 0 (since it is "getpid() +
(n << 22>" where n is always < 1024), so it is okay to cast the
uint32_t to int (thus allowing us to use -1 as an error sentinel).

Until now, virNetlinkCommand has assumed that the nl_pid in the source
address of outgoing netlink messages should always be the return value
of getpid(). In most cases it actually doesn't matter, but in the case
of communication with lldpad, lldpad saves this info and later uses it
to send netlink messages back to libvirt. A recent patch to fix Bug
816465 changed the order of the universe such that the netlink event
service socket is no longer bound with nl_pid == getpid(), so lldpad
could no longer send unsolicited messages to libvirtd. Adding src_pid
as an argument to virNetlinkCommand() is the first step in notifying
lldpad of the proper address of the netlink event service socket.

This is part of the solution to the problem detailed in:

  https://bugzilla.redhat.com/show_bug.cgi?id=816465

and further detailed in

  https://www.redhat.com/archives/libvir-list/2012-May/msg00202.htm

A short explanation is included in the comments of the patch itself.

Note that this patch by itself breaks communication between lldpad and
libvirtd, so the other 3 patches in the series must be applied at the
same time as this patch.

These two functions are called from main() on all platforms, and
always return success on platforms that don't support libnl. They
still log an error message, though, which doesn't make sense - they
should just be NOPs on those platforms. (Per a suggestion during
review, I've turned the logs into debug messages rather than removing
them completely).

configure.ac: check for libnl-3 in addition to libnl-1

src/Makefile.am: link against libnl when needed

src/util/virnetlink.c:
support libnl3 api.  To minimize impact on code flow, wrap the
differences under the virNetlink* namespace.

Unfortunately libnl3 moves netlink/msg.h to
/usr/include/libnl3/netlink/msg.h, so the LIBNL_CFLAGS need to be added
to a bunch of places where they weren't needed with libnl1.
Signed-off-by: NSerge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: NEric Blake <eblake@redhat.com>

Some of the error messages in this function should have been
virReportSystemError (since they have an errno they want to log), but
were mistakenly written as netlinkError, which expects a libvirt error
code instead. The result was that when one of the errors was
encountered, "No error message provided" would be printed instead of
something meaningful (see
https://bugzilla.redhat.com/show_bug.cgi?id=816465 for an example).

When libvirtd is restarted, also restart the netlink event
message callbacks for existing VEPA connections and send
a message to lldpad for these existing links, so it learns
the new libvirtd pid.
Signed-off-by: ND. Herrendoerfer <d.herrendoerfer@herrendoerfer.name>

Return statements with parameter enclosed in parentheses were modified
and parentheses were removed. The whole change was scripted, here is how:

List of files was obtained using this command:
git grep -l -e '\<return\s*([^()]*\(([^()]*)[^()]*\)*)\s*;' |             \
grep -e '\.[ch]$' -e '\.py$'

Found files were modified with this command:
sed -i -e                                                                 \
's_^\(.*\<return\)\s*(\(\([^()]*([^()]*)[^()]*\)*\))\s*\(;.*$\)_\1 \2\4_' \
-e 's_^\(.*\<return\)\s*(\([^()]*\))\s*\(;.*$\)_\1 \2\3_'

Then checked for nonsense.

The whole command looks like this:
git grep -l -e '\<return\s*([^()]*\(([^()]*)[^()]*\)*)\s*;' |             \
grep -e '\.[ch]$' -e '\.py$' | xargs sed -i -e                            \
's_^\(.*\<return\)\s*(\(\([^()]*([^()]*)[^()]*\)*\))\s*\(;.*$\)_\1 \2\4_' \
-e 's_^\(.*\<return\)\s*(\([^()]*\))\s*\(;.*$\)_\1 \2\3_'

There are special stub versions of all public functions in this file
that are compiled when either libnl isn't available or the platform
isn't linux. Each of these functions had two almost identical message,
differing only in the function name included in the message. Since log
messages already contain the function name, we can just define a const
char* with the common part of the string, and use that same string for
all the log messages.

Also, rather than doing #if defined ... #else ... #endif *inside the
error log macro invocation*, this patch does #if defined ... just
once, using it to decide which single string to define. This turns the
error log in each function from 6 lines, to 1 line.

I'm building on OSX with no libnl. I had to do this to get src/util/virnetlink.c to compile:

Commit e3ba4025 introduced a few build errors with HAVE_LIBNL undefined.