This is a self-locking wrapper around virHashTable. Only a limited set
of APIs are implemented now (the ones which are used in the following
patch) as more can be added on demand.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

I almost wrote a hash value free function that just called
VIR_FREE, then realized I couldn't be the first person to
do that.  Sure enough, it was worth factoring into a common
helper routine.

* src/util/virhash.h (virHashValueFree): New function.
* src/util/virhash.c (virHashValueFree): Implement it.
* src/util/virobject.h (virObjectFreeHashData): New function.
* src/libvirt_private.syms (virhash.h, virobject.h): Export them.
* src/nwfilter/nwfilter_learnipaddr.c (virNWFilterLearnInit): Use
common function.
* src/qemu/qemu_capabilities.c (virQEMUCapsCacheNew): Likewise.
* src/qemu/qemu_command.c (qemuDomainCCWAddressSetCreate):
Likewise.
* src/qemu/qemu_monitor.c (qemuMonitorGetBlockInfo): Likewise.
* src/qemu/qemu_process.c (qemuProcessWaitForMonitor): Likewise.
* src/util/virclosecallbacks.c (virCloseCallbacksNew): Likewise.
* src/util/virkeyfile.c (virKeyFileParseGroup): Likewise.
* tests/qemumonitorjsontest.c
(testQemuMonitorJSONqemuMonitorJSONGetBlockInfo): 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 virhash to provide a const-correct interface: all actions
that don't modify the table take a const table.  Note that in
one case (virHashSearch), we actually strip const away - we aren't
modifying the contents of the table, so much as associated data
for ensuring that the code uses the table correctly (if this were
C++, it would be a case for the 'mutable' keyword).

* src/util/virhash.h (virHashKeyComparator, virHashEqual): Use
intended type.
(virHashSize, virHashTableSize, virHashLookup, virHashSearch):
Make const-correct.
* src/util/virhash.c (virHashEqualData, virHashEqual)
(virHashLookup, virHashSize, virHashTableSize, virHashSearch)
(virHashComputeKey): Fix fallout.
* src/conf/nwfilter_params.c
(virNWFilterFormatParameterNameSorter): Likewise.
* src/nwfilter/nwfilter_ebiptables_driver.c
(ebiptablesFilterOrderSort): Likewise.
* tests/virhashtest.c (testHashGetItemsCompKey)
(testHashGetItemsCompValue): Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

Implement function to remove all entries of a hash table.

Some files are using uint32_t or int64_t without including
stdint.h which defines them. Fix this.

Recent discussions have illustrated the potential for DOS attacks
with the hash table implementations used by most languages and
libraries.

   https://lwn.net/Articles/474912/

libvirt has an internal hash table impl, and uses hash tables for
a variety of purposes. The hash key generation code is pretty
simple and thus not strongly collision resistant.

This patch replaces the current libvirt hash key generator with
the (public domain) Murmurhash3 code. In addition every hash
table now gets a random seed value which is used to perturb the
hashing code. This should make it impossible to mount any
practical attack against libvirt hashing code.

* bootstrap.conf: Import bitrotate module
* src/Makefile.am: Add virhashcode.[ch]
* src/util/util.c: Make virRandom() return a fixed 32 bit
  integer value.
* src/util/hash.c, src/util/hash.h, src/util/cgroup.c: Replace
  hash code generation with a call to virHashCodeGen()
* src/util/virhashcode.h, src/util/virhashcode.c: Add a new
  virHashCodeGen() API using the Murmurhash3 algorithm.

In preparation for the patch to include Murmurhash3, which
introduces a virhashcode.h and virhashcode.c files, rename
the existing hash.h and hash.c to virhash.h and virhash.c
respectively.

In preparation for conversion over to use the Murmurhash3
algorithm, convert various virHash APIs to use size_t or
uint32 for their return values/parameters, instead of the
variable size 'unsigned long' or 'int' types

Add function to compare two hash tables for equality.

Add a function to the virHashTable for getting an array of the hash table's
key-value pairs and have the keys (optionally) sorted.
Signed-off-by: NStefan Berger <stefanb@linux.vnet.ibm.com>

This adds several tests for remaining hash APIs (custom
hasher/comparator functions are not covered yet, though).

All tests pass both before and after the "Simplify hash implementation".

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

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.

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

Most of the hash iterators need to modify either payload of
data args. The const annotation prevents this.

* src/util/hash.h, src/util/hash.c: Remove const-ness from
  virHashForEach/Iterator
* src/xen/xm_internal.c: Remove bogus casts

* 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

Done using this command (also includes .c.in and .h.in files):
for i in $(g ls-files|grep -E '\.[ch](\.in)?$'|grep -v gnulib); do
  expand -i $i > j && mv j $i;done

  src/xs_internal.c: implementing domain pointers unification, thread
  safety and reference counting for domain and connections, this was
  the last critical change needed before making further progresses at
  the API level. Still a couple fo things TODO for this, unification
  at the Python level and adding UUID to hash. All domain/connect alloc
  and free routines are now centralized in hash.c
* docs/APIchunk1.html docs/libvirt-api.xml docs/libvirt-refs.xml
  docs/html/libvirt-libvirt.html: regenerated the docs, that doesn't
  change the API.
Daniel

  src/sexpr.h src/virsh.c src/virterror.c src/xen_internal.c
  src/xen_internal.h src/xend_internal.c src/xend_internal.h
  src/xml.c src/xml.h: applied cb/indent to homogenize the source
  style, as a first pass.
Daniel

  version for python bindings, heavilly based on libxml2/libxslt
  way of doing things, maybe this need to be revisited. Added packaging
  too.
* src/hash.h: fixed the Copyright notice.
Daniel

  libvir.spec.in docs/Makefile.am docs/apibuild.py docs/structures.fig
  include/Makefile.am include/libvir.h src/Makefile.am src/hash.c
  src/hash.h src/internal.h src/libvir.c src/libvir_sym.version
  src/virsh.c: renamed to libvir
Daniel