Re: [libvirt] [PATCH v2 1/7] util: introduce virFileCache

The new virFileCache will nicely handle the caching logic for any data that we would like to cache. For each type of data we will just need to implement few handlers that will take care of creating, validating, loading and saving the cached data. The cached data must be an instance of virObject. Currently we cache QEMU capabilities which will start using virFileCache. Signed-off-by: Pavel Hrdina <phrdina(a)redhat.com&gt; --- Notes: Changes in v2: - added suffix argument into virFileCacheNew() - fixed locking for virFileCache APIs - moved virObjectUnref() into virFileCacheLoad() po/POTFILES.in | 1 + src/Makefile.am | 1 + src/libvirt_private.syms | 9 + src/util/virfilecache.c | 439 +++++++++++++++++++++++++++++++++++++++++++++++ src/util/virfilecache.h | 137 +++++++++++++++ 5 files changed, 587 insertions(+) create mode 100644 src/util/virfilecache.c create mode 100644 src/util/virfilecache.h

diff --git a/src/util/virfilecache.c b/src/util/virfilecache.c new file mode 100644 index 0000000000..0401253146 --- /dev/null +++ b/src/util/virfilecache.c @@ -0,0 +1,439 @@

+/** + * virFileCacheNew: + * @dir: the cache directory where all the cache files will be stored + * @suffix: the cache file suffix or NULL if no suffix is required + * @handlers: filled structure with all required handlers + * + * Creates a new cache object which handles caching any data to files + * stored on a filesystem. + * + * Returns new cache object or NULL on error. + */ +virFileCachePtr +virFileCacheNew(const char *dir, + const char *suffix, + virFileCacheHandlers handlers)

+{ + virFileCachePtr cache; + + if (virFileCacheInitialize() < 0) + return NULL; + + if (!(cache = virObjectNew(virFileCacheClass))) + return NULL; + + if (!(cache->table = virHashCreate(10, virObjectFreeHashData))) + goto cleanup; + + if (VIR_STRDUP(cache->dir, dir) < 0) + goto cleanup; + + if (VIR_STRDUP(cache->suffix, suffix) < 0) + goto cleanup; + + cache->handlers = handlers;

+ + return cache; + + cleanup: + virObjectUnref(cache); + return NULL; +}

+/** + * virFileCacheInsertData: + * @cache: existing cache object + * @name: name of the new data + * @data: the actual data object to store in cache + * + * Adds a new data into a cache but doesn't store the data into + * a file. This function should be used only by testing code. + * + * Returns 0 on success, -1 on error. + */ +int +virFileCacheInsertData(virFileCachePtr cache, + const char *name, + void *data) +{ + int rc; + + virObjectLock(cache); + + rc = virHashUpdateEntry(cache->table, name, data); + + virObjectUnlock(cache); + + if (rc < 0) + return -1; + return 0;

+}