diff options
Diffstat (limited to 'src/cyn.c')
| -rw-r--r-- | src/cyn.c | 156 |
1 files changed, 130 insertions, 26 deletions
@@ -28,35 +28,100 @@ #include "queue.h" #include "cyn.h" +#if !CYN_SEARCH_DEEP_MAX +# define CYN_SEARCH_DEEP_MAX 10 +#endif + +/** + * items of the list of observers or awaiters + */ struct callback { + /** link to the next item of the list */ struct callback *next; union { + /** any callback value */ void *any_cb; + /** awaiter callback */ on_enter_cb_t *on_enter_cb; + /** observer callback */ on_change_cb_t *on_change_cb; }; + /** closure of the callback */ void *closure; }; +/** + * items of the list of agents + */ struct agent { + /** link to the next item of the list */ struct agent *next; + + /** agent callback */ agent_cb_t *agent_cb; + + /** closure of the callback */ void *closure; + + /** length of the name */ uint8_t len; + + /** name of the agent */ char name[]; }; +/** + * structure handling an asynchronous check + */ +struct async_check +{ + /** callback for handling result of the check */ + on_result_cb_t *on_result_cb; + + /** closure of the callback */ + void *closure; + + /** key of the check */ + data_key_t key; + + /** value of the check */ + data_value_t value; + + /** down counter for recursivity limitation */ + int decount; +}; + /** locking critical section */ static const void *lock; + +/** head of the list of critical section awaiters */ static struct callback *awaiters; + +/** head of the list of change observers */ static struct callback *observers; + +/** head of the list of agents */ static struct agent *agents; + +/** last changeid */ static uint32_t last_changeid; + +/** changeid of the current 'changeid_string' */ static uint32_t last_changeid_string; + +/** string buffer for changeid */ static char changeid_string[12]; +/** + * Delete from the list represented by 'head' the entry for + * 'callback' and 'closure' + * @param callback + * @param closure + * @param head + * @return 0 if entry found and removed, -ENOENT if not found + */ static int delcb( @@ -70,13 +135,21 @@ delcb( if (c->any_cb == callback && c->closure == closure) { *head = c->next; free(c); - return 1; + return 0; } head = &c->next; } - return 0; + return -ENOENT; } +/** + * Adds at head of the list represented by 'head' the entry for + * 'callback' and 'closure' + * @param callback + * @param closure + * @param head + * @return 0 if correctly added or -ENOMEM in case of allocation failure + */ static int addcb( @@ -88,7 +161,7 @@ addcb( c = malloc(sizeof *c); if (c == NULL) - return -(errno = ENOMEM); + return -ENOMEM; c->any_cb = callback; c->closure = closure; c->next = *head; @@ -96,6 +169,10 @@ addcb( return 0; } +/** + * Call when database changed. + * Calls all observers to notify them the change + */ static void changed( @@ -107,30 +184,36 @@ changed( c->on_change_cb(c->closure); } -/** enter critical recoverable section */ +/* see cyn.h */ int cyn_enter( const void *magic ) { + if (!magic) + return -EINVAL; if (lock) return -EBUSY; lock = magic; return 0; } +/* see cyn.h */ int cyn_enter_async( on_enter_cb_t *enter_cb, - void *closure + void *magic ) { + if (!magic) + return -EINVAL; if (lock) - return addcb(enter_cb, closure, &awaiters); + return addcb(enter_cb, magic, &awaiters); - lock = closure; - enter_cb(closure); + lock = magic; + enter_cb(magic); return 0; } +/* see cyn.h */ int cyn_enter_async_cancel( on_enter_cb_t *enter_cb, @@ -139,6 +222,7 @@ cyn_enter_async_cancel( return delcb(enter_cb, closure, &awaiters); } +/* see cyn.h */ int cyn_on_change_add( on_change_cb_t *on_change_cb, @@ -147,6 +231,7 @@ cyn_on_change_add( return addcb(on_change_cb, closure, &observers); } +/* see cyn.h */ int cyn_on_change_remove( on_change_cb_t *on_change_cb, @@ -155,7 +240,7 @@ cyn_on_change_remove( return delcb(on_change_cb, closure, &observers); } -/** leave critical recoverable section */ +/* see cyn.h */ int cyn_leave( const void *magic, @@ -205,6 +290,7 @@ cyn_leave( return rc; } +/* see cyn.h */ int cyn_set( const data_key_t *key, @@ -215,6 +301,7 @@ cyn_set( return queue_set(key, value); } +/* see cyn.h */ int cyn_drop( const data_key_t *key @@ -224,6 +311,7 @@ cyn_drop( return queue_drop(key); } +/* see cyn.h */ void cyn_list( void *closure, @@ -233,6 +321,11 @@ cyn_list( db_for_all(closure, callback, key); } +/** + * initialize value to its default + * @param value to initialize + * @return the initialized value + */ static data_value_t * default_value( @@ -243,6 +336,13 @@ default_value( return value; } +/** + * Search the agent of name and return its item in the list + * @param name of the agent to find (optionally zero terminated) + * @param len length of the name + * @param ppprev for catching the pointer referencing the return item + * @return 0 if not found or the pointer to the item of the found agent + */ static struct agent * search_agent( @@ -260,6 +360,12 @@ search_agent( return it; } +/** + * Return the agent required by the value or 0 if no agent is required + * or if the agent is not found. + * @param value string where agent is the prefix followed by one colon + * @return the item of the required agent or 0 when no agent is required + */ static struct agent * required_agent( @@ -274,14 +380,6 @@ required_agent( return 0; } -struct async_check -{ - on_result_cb_t *on_result_cb; - void *closure; - data_key_t key; - data_value_t value; - int decount; -}; static void @@ -334,13 +432,12 @@ async_on_result( async_reply(achk); } -static int -async_check_or_test( +cyn_query_async( on_result_cb_t *on_result_cb, void *closure, const data_key_t *key, - int agentdeep + int maxdepth ) { int rc; data_value_t value; @@ -361,7 +458,7 @@ async_check_or_test( /* if not an agent or agent not required */ agent = required_agent(value.value); - if (!agent || !agentdeep) { + if (!agent || maxdepth <= 0) { on_result_cb(closure, &value); return rc; } @@ -406,31 +503,34 @@ async_check_or_test( ptr = mempcpy(ptr, key->permission, szper); } achk->value = value; - achk->decount = agentdeep; + achk->decount = maxdepth; /* call the agent */ async_call_agent(agent, achk); return 0; } +/* see cyn.h */ int cyn_test_async( on_result_cb_t *on_result_cb, void *closure, const data_key_t *key ) { - return async_check_or_test(on_result_cb, closure, key, 0); + return cyn_query_async(on_result_cb, closure, key, 0); } +/* see cyn.h */ int cyn_check_async( on_result_cb_t *on_result_cb, void *closure, const data_key_t *key ) { - return async_check_or_test(on_result_cb, closure, key, 10); + return cyn_query_async(on_result_cb, closure, key, CYN_SEARCH_DEEP_MAX); } +/* see cyn.h */ int cyn_agent_add( const char *name, @@ -464,6 +564,7 @@ cyn_agent_add( return 0; } +/* see cyn.h */ int cyn_agent_remove( const char *name @@ -486,25 +587,28 @@ cyn_agent_remove( return 0; } +/* see cyn.h */ void cyn_changeid_reset( ) { last_changeid = 1; } +/* see cyn.h */ uint32_t cyn_changeid( ) { return last_changeid; } -extern +/* see cyn.h */ const char * cyn_changeid_string( ) { + /* regenerate the string on need */ if (last_changeid != last_changeid_string) { last_changeid_string = last_changeid; snprintf(changeid_string, sizeof changeid_string, "%u", last_changeid); } return changeid_string; -}
\ No newline at end of file +} |