From e1b959ccbb4e47421b37a0f75a2bf89ccd34dcb1 Mon Sep 17 00:00:00 2001 From: "David M. Lee" Date: Thu, 1 Aug 2013 13:49:34 +0000 Subject: Split caching out from the stasis_caching_topic. In working with res_stasis, I discovered a significant limitation to the current structure of stasis_caching_topics: you cannot subscribe to cache updates for a single channel/bridge/endpoint/etc. To address this, this patch splits the cache away from the stasis_caching_topic, making it a first class object. The stasis_cache object is shared amongst individual stasis_caching_topics that are created per channel/endpoint/etc. These are still forwarded to global whatever_all_cached topics, so their use from most of the code does not change. In making these changes, I noticed that we frequently used a similar pattern for bridges, endpoints and channels: single_topic ----------------> all_topic ^ | single_topic_cached ----+----> all_topic_cached | +----> cache This pattern was extracted as the 'Stasis Caching Pattern', defined in stasis_caching_pattern.h. This avoids a lot of duplicate code between the different domain objects. Since the cache is now disassociated from its upstream caching topics, this also necessitated a change to how the 'guaranteed' flag worked for retrieving from a cache. The code for handling the caching guarantee was extracted into a 'stasis_topic_wait' function, which works for any stasis_topic. (closes issue ASTERISK-22002) Review: https://reviewboard.asterisk.org/r/2672/ git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@395954 65c4cc65-6c06-0410-ace0-fbb531ad65f3 --- main/presencestate.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) (limited to 'main/presencestate.c') diff --git a/main/presencestate.c b/main/presencestate.c index 45174d5a1..3f394b635 100644 --- a/main/presencestate.c +++ b/main/presencestate.c @@ -55,6 +55,7 @@ static const struct { STASIS_MESSAGE_TYPE_DEFN(ast_presence_state_message_type); struct stasis_topic *presence_state_topic_all; +struct stasis_cache *presence_state_cache; struct stasis_caching_topic *presence_state_topic_cached; /*! \brief A presence state provider */ @@ -95,7 +96,7 @@ static enum ast_presence_state presence_state_cached(const char *presence_provid RAII_VAR(struct stasis_message *, msg, NULL, ao2_cleanup); struct ast_presence_state_message *presence_state; - msg = stasis_cache_get(ast_presence_state_topic_cached(), ast_presence_state_message_type(), presence_provider); + msg = stasis_cache_get(ast_presence_state_cache(), ast_presence_state_message_type(), presence_provider); if (!msg) { return res; @@ -294,9 +295,14 @@ struct stasis_topic *ast_presence_state_topic_all(void) return presence_state_topic_all; } -struct stasis_caching_topic *ast_presence_state_topic_cached(void) +struct stasis_cache *ast_presence_state_cache(void) { - return presence_state_topic_cached; + return presence_state_cache; +} + +struct stasis_topic *ast_presence_state_topic_cached(void) +{ + return stasis_caching_get_topic(presence_state_topic_cached); } static const char *presence_state_get_id(struct stasis_message *msg) @@ -314,6 +320,8 @@ static void presence_state_engine_cleanup(void) { ao2_cleanup(presence_state_topic_all); presence_state_topic_all = NULL; + ao2_cleanup(presence_state_cache); + presence_state_cache = NULL; presence_state_topic_cached = stasis_caching_unsubscribe_and_join(presence_state_topic_cached); STASIS_MESSAGE_TYPE_CLEANUP(ast_presence_state_message_type); } @@ -331,7 +339,12 @@ int ast_presence_state_engine_init(void) return -1; } - presence_state_topic_cached = stasis_caching_topic_create(presence_state_topic_all, presence_state_get_id); + presence_state_cache = stasis_cache_create(presence_state_get_id); + if (!presence_state_cache) { + return -1; + } + + presence_state_topic_cached = stasis_caching_topic_create(presence_state_topic_all, presence_state_cache); if (!presence_state_topic_cached) { return -1; } -- cgit v1.2.3