* src/util/logging.c: fix virLogDumpAllFD() to avoid snprintf, simplify
  the code and provide more useful signal descriptions. Also remove an
  unused variable.

Signed-off-by: NEric Blake <eblake@redhat.com>

virLogEmergencyDumpAll() allows to dump the content of the
debug buffer from within a signal handler. It saves to all
log file or stderr if none is found
* src/util/logging.h src/util/logging.c: add the new API
  and cleanup the old virLogDump code
* src/libvirt_private.syms: exports it as a private symbol

* src/util/logging.c: the start pointer need to wrap around too

Initially only the log actually written out by libvirt were
saved on the memory buffer, this patch forces all informations
including info and debug to be saved in memory too. This is
useful to get full data in case of crash.

In virFileOperation, the parent does a fallback to a non-fork
attempt if it detects that the child returned EACCES.  However,
the child was calling _exit(-EACCES), which does _not_ appear
as EACCES in the parent.

* src/util/util.c (virFileOperation): Correctly pass EACCES from
child to parent.

This fixes a possible crash of libvirtd during its startup. When qemu
driver reconnects to running domains, it iterates over all domain
objects in a hash. When reconnecting to an associated qemu monitor
fails and the domain is transient, it's immediately removed from the
hash. Despite the fact that it's explicitly forbidden to do so. If
libvirtd is lucky enough, virHashForEach will access random memory when
the callback finishes and the deamon will crash.

Since it's trivial to fix virHashForEach to allow removal of hash
entries while iterating through them, I went this way instead of fixing
qemuReconnectDomain callback (and possibly others) to avoid deleting the
entries.

Replace the 'Unknown failure' error message with something a
little bit more descriptive.

* src/util/virterror.c: Improve error message

The kill() function doesn't exist on Win32, so it needs to be
checked for at build time & code disabled in cgroups

* configure.ac: Check for kill()
* src/util/cgroup.c: Stub out virCGroupKill* functions
  when kill() isn't available

The virCgroupKill method kills all PIDs found in a cgroup

The virCgroupKillRecursively method does this recursively
for child cgroups.

The virCgroupKillPainfully method does a recursive kill
several times in a row until everything has really died

Relax the restriction that the hash table key must be a string
by allowing an arbitrary hash code generator + comparison func
to be provided

* util/hash.c, util/hash.h: Allow any pointer as a key
* internal.h: Include stdbool.h as standard.
* conf/domain_conf.c, conf/domain_conf.c,
  conf/nwfilter_params.c, nwfilter/nwfilter_gentech_driver.c,
  nwfilter/nwfilter_gentech_driver.h, nwfilter/nwfilter_learnipaddr.c,
  qemu/qemu_command.c, qemu/qemu_driver.c,
  qemu/qemu_process.c, uml/uml_driver.c,
  xen/xm_internal.c: s/char */void */ in hash callbacks

Since the deallocator is passed into the constructor of
a hash table it is not desirable to pass it into each
function again. Remove it from all functions, but provide
a virHashSteal to allow a item to be removed from a hash
table without deleteing it.

* src/util/hash.c, src/util/hash.h: Remove deallocator
  param from all functions. Add virHashSteal
* src/libvirt_private.syms: Add virHashSteal
* src/conf/domain_conf.c, src/conf/nwfilter_params.c,
  src/nwfilter/nwfilter_learnipaddr.c,
  src/qemu/qemu_command.c, src/xen/xm_internal.c: Update
  for changed hash API

Replace wrong "set" by correct "seek" in error message.
Signed-off-by: NPhilipp Hahn <hahn@univention.de>

* src/util/cgroup.c (virCgroupAllowDevicePath)
(virCgroupDenyDevicePath): Don't fail with EINVAL for
non-devices.
* src/qemu/qemu_driver.c (qemudDomainSaveFlag): Update caller.
* src/qemu/qemu_cgroup.c (qemuSetupDiskPathAllow)
(qemuSetupChardevCgroup, qemuSetupHostUsbDeviceCgroup)
(qemuSetupCgroup, qemuTeardownDiskPathDeny): Likewise.

valgrind warns:

==21079== Syscall param rt_sigaction(act->sa_mask) points to uninitialised byte(s)
==21079==    at 0x329840F63E: __libc_sigaction (sigaction.c:67)
==21079==    by 0x4E5A8E7: __virExec (util.c:661)

Regression introduced in commit ab07533e.  Technically, sa_mask
shouldn't affect operation if sa_flags selects sa_handler, and
sa_handler selects SIG_IGN, but better safe than sorry.

* src/util/util.c (__virExec): Supply missing sigemptyset.

Remove the <stdbool.h> header from all source files / headers
and just put it into internal.h

* src/internal.h: Add <stdbool.h>

The virFileAbsPath was not taking into account the '/' directory
separator when allocating memory for combining cwd + path. Convert
to use virAsprintf to avoid this type of bug completely.

* src/util/util.c: Convert virFileAbsPath to use virAsprintf

Current code does an IFF_UP on a 8021Qbh interface immediately after a port
profile set. This is ok in most cases except when its the migration prepare
stage. During migration we want to postpone IFF_UP'ing the interface on the
destination host until the source host has disassociated the interface.
This patch moves IFF_UP of the interface to the final stage of migration.
The motivation for this change is to postpone any addr registrations on the
destination host until the source host has done the addr deregistrations.

While at it, for symmetry with associate move ifDown of a 8021Qbh interface
to before disassociate

Done mechanically with:
$ git grep -l '\bDEBUG0\? *(' | xargs -L1 sed -i 's/\bDEBUG0\? *(/VIR_&/'

followed by manual deletion of qemudDebug in daemon/libvirtd.c, along
with a single 'make syntax-check' fallout in the same file, and the
actual deletion in src/util/logging.h.

* src/util/logging.h (DEBUG, DEBUG0): Delete.
* daemon/libvirtd.h (qemudDebug): Likewise.
* global: Change remaining clients over to VIR_DEBUG counterpart.

Two-argument free functions are uncommon; match the style elsewhere
by caching the callback at creation.

* src/util/hash.h (virHashCreate, virHashFree): Move deallocator
argument to creation.
* cfg.mk (useless_free_options): Add virHashFree.
* src/util/hash.c (_virHashTable): Track deallocator.
(virHashCreate, virHashFree): Update to new signature.
* src/conf/domain_conf.c (virDomainObjListDeinit)
(virDomainObjListInit, virDomainDiskDefForeachPath)
(virDomainSnapshotObjListDeinit, virDomainSnapshotObjListInit):
Update callers.
* src/conf/nwfilter_params.c (virNWFilterHashTableFree)
(virNWFilterHashTableCreate): Likewise.
* src/conf/nwfilter_conf.c (virNWFilterTriggerVMFilterRebuild):
Likewise.
* src/cpu/cpu_generic.c (genericHashFeatures, genericBaseline):
Likewise.
* src/xen/xm_internal.c (xenXMOpen, xenXMClose): Likewise.
* src/nwfilter/nwfilter_learnipaddr.c (virNWFilterLearnInit)
(virNWFilterLearnShutdown): Likewise.
* src/qemu/qemu_command.c (qemuDomainPCIAddressSetCreate)
(qemuDomainPCIAddressSetFree): Likewise.
* src/qemu/qemu_process.c (qemuProcessWaitForMonitor): Likewise.

Two regressions:
Commit df1011ca broke builds for systems that lack devmapper
(non-Linux, as well as Linux with ./autogen.sh --without-libvirtd
and without the libraries present).
Commit ce6fd650 broke cross-compilation, due to a gnulib bug.

* .gnulib: Update to latest, for cross-compilation fix.
* src/util/util.c (virIsDevMapperDevice): Provide stub for
platforms not using storage driver.
* configure.ac (devmapper): Arrange to define HAVE_LIBDEVMAPPER_H.
devmapper issue reported by Wen Congyang.

The only difference between these 2 functions is that one errors
out when the entry is already present while the other modifies
the existing entry. Add an helper function with a boolean argument
indicating whether existing entries should be updated or not, and
use this helper in both functions.

The code in virHashUpdateEntry and virHashAddEntry is really
similar. However, the latter rebalances the hash table when
one of its buckets contains too many elements while the former
does not. Fix this discrepancy.

* src/util/hash.c (virHashGrow) [DEBUG_GROW]: Use modern logging.
Reported by Christophe Fergeau.

Followup to commit 17e19add, and would have prevented the bug
independently fixed in commit 76c57a7c.

* src/util/logging.c (virLogMessage): Preserve errno, since
logging should be as unintrusive as possible.

An upcoming patch has a use for a tap device to be created that
doesn't need to be actually put into the "up" state, and keeping it
"down" keeps the output of ifconfig from being unnecessarily cluttered
(ifconfig won't show down interfaces unless you add "-a").

bridge.[ch]: add "up" as an arg to brAddTap()
uml_conf.c, qemu_command.c: add "up" (set to "true") to brAddTap() call.

The name convention of device mapper disk is different, and 'parted'
can't be used to delete a device mapper disk partition. e.g.

Name                 Path
-----------------------------------------
3600a0b80005ad1d7000093604cae912fp1 /dev/mapper/3600a0b80005ad1d7000093604cae912fp1

Error: Expecting a partition number.

This patch introduces 'dmsetup' to fix it.

Changes:
  - New function "virIsDevMapperDevice" in "src/utils/utils.c"
  - remove "is_dm_device" in "src/storage/parthelper.c", use
    "virIsDevMapperDevice" instead.
  - Requires "device-mapper" for 'with-storage-disk" in "libvirt.spec.in"
  - Check "dmsetup" in 'configure.ac' for "with-storage-disk"
  - Changes on "src/Makefile.am" to link against libdevmapper
  - New entry for "virIsDevMapperDevice" in "src/libvirt_private.syms"

Changes from v1 to v3:
  - s/virIsDeviceMapperDevice/virIsDevMapperDevice/g
  - replace "virRun" with "virCommand"
  - sort the list of util functions in "libvirt_private.syms"
  - ATTRIBUTE_NONNULL(1) for virIsDevMapperDevice declaration.

e.g.

Name                 Path
-----------------------------------------
3600a0b80005ad1d7000093604cae912fp1 /dev/mapper/3600a0b80005ad1d7000093604cae912fp1

Vol /dev/mapper/3600a0b80005ad1d7000093604cae912fp1 deleted

Name                 Path
-----------------------------------------

* src/util/cgroup.c (virCgroupSetValueStr, virCgroupGetValueStr)
(virCgroupRemoveRecursively): VIR_DEBUG can clobber errno.
(virCgroupRemove): Use VIR_DEBUG rather than DEBUG.

clang had 5 reports against virCommand; three were false positives
(a NULL deref in ProcessIO solved by sa_assert, and two uninitialized
memory operations solved by adding an initializer), but two were real.

* src/util/command.c (virCommandProcessIO): Fix real bug of
possible NULL dereference.  Teach clang that buf is never NULL.
(virCommandRun): Teach clang that infd is only ever accessed when
initialized.

* src/util/threads-pthread.c: Fix mutex leak

This helps identifying which command exited with status != 0.

A couple of allocation were not calling virReportOOMError on allocation
errors

* src/util/hash.c: add the needed call in virHashCreate and
  virHashAddOrUpdateEntry

clang complained that STREQ(group->controllers[i].mountPoint,...)  was
a NULL dereference when i==VIR_CGROUP_CONTROLLER_CPUSET, because it
assumes the worst about virCgroupPathOfController.  Marking the
argument const doesn't yet have an effect, per this clang bug:
http://llvm.org/bugs/show_bug.cgi?id=7758

So, we use sa_assert, which was designed to shut up false positives
from tools like clang.

* src/util/cgroup.c (virCgroupMakeGroup): Teach clang that there
is no NULL dereference.

Detected by clang.

* src/util/xml.c (virXPathStringLimit): Use %zd, not obsolete %Zd.

* src/util/hash.c: virHashAddEntry and virHashUpdateEntry were missing NULL
  checks on strdup
* AUTHORS: add Christophe Fergeau

Building the 0.8.8 release candidate on cygwin produced this compiler
warning, which is indicative of catastrophic failure on any attempt to
print an error message with errno turned to a string:

  CC       strerror_r.lo
strerror_r.c: In function 'rpl_strerror_r':
strerror_r.c:67: warning: assignment makes integer from pointer without a cast

This has been fixed in gnulib.

* .gnulib: Update to latest, for strerror_r fix.
* src/util/memory.c (includes): Satisfy 'make syntax-check'.