diff options
| -rw-r--r-- | src/afb-hook.c | 289 |
1 files changed, 163 insertions, 126 deletions
diff --git a/src/afb-hook.c b/src/afb-hook.c index 3d57ca52..3fcd36d0 100644 --- a/src/afb-hook.c +++ b/src/afb-hook.c @@ -116,8 +116,9 @@ struct afb_hook_global { void *closure; /**< closure for callbacks */ }; -/* synchronisation across threads */ +/* synchronization across threads */ static pthread_rwlock_t rwlock = PTHREAD_RWLOCK_INITIALIZER; +static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER; /* list of hooks for xreq */ static struct afb_hook_xreq *list_of_xreq_hooks = NULL; @@ -171,24 +172,6 @@ static char *_pbuf_(const char *fmt, va_list args, char **palloc, char *sbuf, si return sbuf; } -#if 0 /* old behaviour: use NOTICE */ -static void _hook_(const char *fmt1, const char *fmt2, va_list arg2, ...) -{ - char *tag, *data, *mem1, *mem2, buf1[256], buf2[2000]; - va_list arg1; - - data = _pbuf_(fmt2, arg2, &mem2, buf2, sizeof buf2, NULL); - - va_start(arg1, arg2); - tag = _pbuf_(fmt1, arg1, &mem1, buf1, sizeof buf1, NULL); - va_end(arg1); - - NOTICE("[HOOK %s] %s", tag, data); - - free(mem1); - free(mem2); -} -#else /* new behaviour: emits directly to stderr */ static void _hook_(const char *fmt1, const char *fmt2, va_list arg2, ...) { static const char chars[] = "HOOK: [] \n"; @@ -196,18 +179,23 @@ static void _hook_(const char *fmt1, const char *fmt2, va_list arg2, ...) struct iovec iov[5]; va_list arg1; + /* "HOOK: [" */ iov[0].iov_base = (void*)&chars[0]; iov[0].iov_len = 7; + /* fmt1 ... */ va_start(arg1, arg2); iov[1].iov_base = _pbuf_(fmt1, arg1, &mem1, buf1, sizeof buf1, &iov[1].iov_len); va_end(arg1); + /* "] " */ iov[2].iov_base = (void*)&chars[7]; iov[2].iov_len = 2; + /* fmt2 arg2 */ iov[3].iov_base = _pbuf_(fmt2, arg2, &mem2, buf2, sizeof buf2, &iov[3].iov_len); + /* "\n" */ iov[4].iov_base = (void*)&chars[9]; iov[4].iov_len = 1; @@ -216,7 +204,6 @@ static void _hook_(const char *fmt1, const char *fmt2, va_list arg2, ...) free(mem1); free(mem2); } -#endif static void _hook_xreq_(const struct afb_xreq *xreq, const char *format, ...) { @@ -413,7 +400,8 @@ static struct afb_hook_xreq_itf hook_xreq_default_itf = { init_hookid(&hookid); \ hook = list_of_xreq_hooks; \ while (hook) { \ - if (hook->itf->hook_xreq_##func \ + if (hook->refcount \ + && hook->itf->hook_xreq_##func \ && (hook->flags & afb_hook_flag_req_##flag) != 0 \ && (!hook->session || hook->session == xreq->context.session) \ && MATCH_API(hook->api, xreq->request.called_api) \ @@ -569,10 +557,10 @@ struct json_object *afb_hook_xreq_get_client_info(const struct afb_xreq *xreq, s void afb_hook_init_xreq(struct afb_xreq *xreq) { - static int reqindex; + static int reqindex = 0; int f, flags; - int add; + int add, x; struct afb_hook_xreq *hook; /* scan hook list to get the expected flags */ @@ -594,11 +582,10 @@ void afb_hook_init_xreq(struct afb_xreq *xreq) /* store the hooking data */ xreq->hookflags = flags; if (flags) { - pthread_rwlock_wrlock(&rwlock); - if (++reqindex < 0) - reqindex = 1; - xreq->hookindex = reqindex; - pthread_rwlock_unlock(&rwlock); + do { + x = __atomic_load_n(&reqindex, __ATOMIC_RELAXED); + xreq->hookindex = (x + 1) % 1000000 ?: 1; + } while (x != __atomic_exchange_n(&reqindex, xreq->hookindex, __ATOMIC_RELAXED)); } } @@ -631,10 +618,10 @@ struct afb_hook_xreq *afb_hook_create_xreq(const char *api, const char *verb, st hook->closure = closure; /* record the hook */ - pthread_rwlock_wrlock(&rwlock); + pthread_mutex_lock(&mutex); hook->next = list_of_xreq_hooks; list_of_xreq_hooks = hook; - pthread_rwlock_unlock(&rwlock); + pthread_mutex_unlock(&mutex); /* returns it */ return hook; @@ -642,31 +629,34 @@ struct afb_hook_xreq *afb_hook_create_xreq(const char *api, const char *verb, st struct afb_hook_xreq *afb_hook_addref_xreq(struct afb_hook_xreq *hook) { - pthread_rwlock_wrlock(&rwlock); - hook->refcount++; - pthread_rwlock_unlock(&rwlock); + __atomic_add_fetch(&hook->refcount, 1, __ATOMIC_RELAXED); return hook; } -void afb_hook_unref_xreq(struct afb_hook_xreq *hook) +static void hook_clean_xreq() { - struct afb_hook_xreq **prv; + struct afb_hook_xreq **prv, *hook, *head; - if (hook) { - pthread_rwlock_wrlock(&rwlock); - if (--hook->refcount) - hook = NULL; - else { - /* unlink */ - prv = &list_of_xreq_hooks; - while (*prv && *prv != hook) + if (pthread_rwlock_trywrlock(&rwlock) == 0) { + /* unlink under mutex */ + head = NULL; + pthread_mutex_lock(&mutex); + prv = &list_of_xreq_hooks; + while ((hook = *prv)) { + if (hook->refcount) prv = &(*prv)->next; - if(*prv) + else { *prv = hook->next; + hook->next = head; + head = hook; + } } + pthread_mutex_unlock(&mutex); pthread_rwlock_unlock(&rwlock); - if (hook) { - /* free */ + + /* free found hooks */ + while((hook = head)) { + head = hook->next; free(hook->api); free(hook->verb); if (hook->session) @@ -676,6 +666,12 @@ void afb_hook_unref_xreq(struct afb_hook_xreq *hook) } } +void afb_hook_unref_xreq(struct afb_hook_xreq *hook) +{ + if (hook && !__atomic_sub_fetch(&hook->refcount, 1, __ATOMIC_RELAXED)) + hook_clean_xreq(); +} + /****************************************************************************** * section: default callbacks for tracing daemon interface *****************************************************************************/ @@ -972,7 +968,8 @@ static struct afb_hook_api_itf hook_api_default_itf = { init_hookid(&hookid); \ hook = list_of_api_hooks; \ while (hook) { \ - if (hook->itf->hook_api_##func \ + if (hook->refcount \ + && hook->itf->hook_api_##func \ && (hook->flags & afb_hook_flag_api_##flag) != 0 \ && MATCH_API(hook->api, apiname)) { \ hook->itf->hook_api_##func(hook->closure, &hookid, __VA_ARGS__); \ @@ -1245,10 +1242,10 @@ struct afb_hook_api *afb_hook_create_api(const char *api, int flags, struct afb_ hook->closure = closure; /* record the hook */ - pthread_rwlock_wrlock(&rwlock); + pthread_mutex_lock(&mutex); hook->next = list_of_api_hooks; list_of_api_hooks = hook; - pthread_rwlock_unlock(&rwlock); + pthread_mutex_unlock(&mutex); /* returns it */ return hook; @@ -1256,37 +1253,46 @@ struct afb_hook_api *afb_hook_create_api(const char *api, int flags, struct afb_ struct afb_hook_api *afb_hook_addref_api(struct afb_hook_api *hook) { - pthread_rwlock_wrlock(&rwlock); - hook->refcount++; - pthread_rwlock_unlock(&rwlock); + __atomic_add_fetch(&hook->refcount, 1, __ATOMIC_RELAXED); return hook; } -void afb_hook_unref_api(struct afb_hook_api *hook) +static void hook_clean_api() { - struct afb_hook_api **prv; + struct afb_hook_api **prv, *hook, *head; - if (hook) { - pthread_rwlock_wrlock(&rwlock); - if (--hook->refcount) - hook = NULL; - else { - /* unlink */ - prv = &list_of_api_hooks; - while (*prv && *prv != hook) + if (pthread_rwlock_trywrlock(&rwlock) == 0) { + /* unlink under mutex */ + head = NULL; + pthread_mutex_lock(&mutex); + prv = &list_of_api_hooks; + while ((hook = *prv)) { + if (hook->refcount) prv = &(*prv)->next; - if(*prv) + else { *prv = hook->next; + hook->next = head; + head = hook; + } } + pthread_mutex_unlock(&mutex); pthread_rwlock_unlock(&rwlock); - if (hook) { - /* free */ + + /* free found hooks */ + while((hook = head)) { + head = hook->next; free(hook->api); free(hook); } } } +void afb_hook_unref_api(struct afb_hook_api *hook) +{ + if (hook && !__atomic_sub_fetch(&hook->refcount, 1, __ATOMIC_RELAXED)) + hook_clean_api(); +} + /****************************************************************************** * section: default callbacks for tracing service interface (evt) *****************************************************************************/ @@ -1362,7 +1368,8 @@ static struct afb_hook_evt_itf hook_evt_default_itf = { init_hookid(&hookid); \ hook = list_of_evt_hooks; \ while (hook) { \ - if (hook->itf->hook_evt_##what \ + if (hook->refcount \ + && hook->itf->hook_evt_##what \ && (hook->flags & afb_hook_flag_evt_##what) != 0 \ && MATCH_EVENT(hook->pattern, evt)) { \ hook->itf->hook_evt_##what(hook->closure, &hookid, __VA_ARGS__); \ @@ -1457,10 +1464,10 @@ struct afb_hook_evt *afb_hook_create_evt(const char *pattern, int flags, struct hook->closure = closure; /* record the hook */ - pthread_rwlock_wrlock(&rwlock); + pthread_mutex_lock(&mutex); hook->next = list_of_evt_hooks; list_of_evt_hooks = hook; - pthread_rwlock_unlock(&rwlock); + pthread_mutex_unlock(&mutex); /* returns it */ return hook; @@ -1468,37 +1475,46 @@ struct afb_hook_evt *afb_hook_create_evt(const char *pattern, int flags, struct struct afb_hook_evt *afb_hook_addref_evt(struct afb_hook_evt *hook) { - pthread_rwlock_wrlock(&rwlock); - hook->refcount++; - pthread_rwlock_unlock(&rwlock); + __atomic_add_fetch(&hook->refcount, 1, __ATOMIC_RELAXED); return hook; } -void afb_hook_unref_evt(struct afb_hook_evt *hook) +static void hook_clean_evt() { - struct afb_hook_evt **prv; + struct afb_hook_evt **prv, *hook, *head; - if (hook) { - pthread_rwlock_wrlock(&rwlock); - if (--hook->refcount) - hook = NULL; - else { - /* unlink */ - prv = &list_of_evt_hooks; - while (*prv && *prv != hook) + if (pthread_rwlock_trywrlock(&rwlock) == 0) { + /* unlink under mutex */ + head = NULL; + pthread_mutex_lock(&mutex); + prv = &list_of_evt_hooks; + while ((hook = *prv)) { + if (hook->refcount) prv = &(*prv)->next; - if(*prv) + else { *prv = hook->next; + hook->next = head; + head = hook; + } } + pthread_mutex_unlock(&mutex); pthread_rwlock_unlock(&rwlock); - if (hook) { - /* free */ + + /* free found hooks */ + while((hook = head)) { + head = hook->next; free(hook->pattern); free(hook); } } } +void afb_hook_unref_evt(struct afb_hook_evt *hook) +{ + if (hook && !__atomic_sub_fetch(&hook->refcount, 1, __ATOMIC_RELAXED)) + hook_clean_evt(); +} + /****************************************************************************** * section: default callbacks for sessions (session) *****************************************************************************/ @@ -1562,7 +1578,8 @@ static struct afb_hook_session_itf hook_session_default_itf = { init_hookid(&hookid); \ hook = list_of_session_hooks; \ while (hook) { \ - if (hook->itf->hook_session_##what \ + if (hook->refcount \ + && hook->itf->hook_session_##what \ && (hook->flags & afb_hook_flag_session_##what) != 0 \ && MATCH_SESSION(hook->pattern, (sessid?:(sessid=afb_session_uuid(session))))) { \ hook->itf->hook_session_##what(hook->closure, &hookid, __VA_ARGS__); \ @@ -1629,10 +1646,10 @@ struct afb_hook_session *afb_hook_create_session(const char *pattern, int flags, hook->closure = closure; /* record the hook */ - pthread_rwlock_wrlock(&rwlock); + pthread_mutex_lock(&mutex); hook->next = list_of_session_hooks; list_of_session_hooks = hook; - pthread_rwlock_unlock(&rwlock); + pthread_mutex_unlock(&mutex); /* returns it */ return hook; @@ -1640,37 +1657,46 @@ struct afb_hook_session *afb_hook_create_session(const char *pattern, int flags, struct afb_hook_session *afb_hook_addref_session(struct afb_hook_session *hook) { - pthread_rwlock_wrlock(&rwlock); - hook->refcount++; - pthread_rwlock_unlock(&rwlock); + __atomic_add_fetch(&hook->refcount, 1, __ATOMIC_RELAXED); return hook; } -void afb_hook_unref_session(struct afb_hook_session *hook) +static void hook_clean_session() { - struct afb_hook_session **prv; + struct afb_hook_session **prv, *hook, *head; - if (hook) { - pthread_rwlock_wrlock(&rwlock); - if (--hook->refcount) - hook = NULL; - else { - /* unlink */ - prv = &list_of_session_hooks; - while (*prv && *prv != hook) + if (pthread_rwlock_trywrlock(&rwlock) == 0) { + /* unlink under mutex */ + head = NULL; + pthread_mutex_lock(&mutex); + prv = &list_of_session_hooks; + while ((hook = *prv)) { + if (hook->refcount) prv = &(*prv)->next; - if(*prv) + else { *prv = hook->next; + hook->next = head; + head = hook; + } } + pthread_mutex_unlock(&mutex); pthread_rwlock_unlock(&rwlock); - if (hook) { - /* free */ + + /* free found hooks */ + while((hook = head)) { + head = hook->next; free(hook->pattern); free(hook); } } } +void afb_hook_unref_session(struct afb_hook_session *hook) +{ + if (hook && !__atomic_sub_fetch(&hook->refcount, 1, __ATOMIC_RELAXED)) + hook_clean_session(); +} + /****************************************************************************** * section: default callbacks for globals (global) *****************************************************************************/ @@ -1716,7 +1742,8 @@ static struct afb_hook_global_itf hook_global_default_itf = { init_hookid(&hookid); \ hook = list_of_global_hooks; \ while (hook) { \ - if (hook->itf->hook_global_##what \ + if (hook->refcount \ + && hook->itf->hook_global_##what \ && (hook->flags & afb_hook_flag_global_##what) != 0) { \ hook->itf->hook_global_##what(hook->closure, &hookid, __VA_ARGS__); \ } \ @@ -1741,7 +1768,8 @@ static void update_global() pthread_rwlock_rdlock(&rwlock); hook = list_of_global_hooks; while (hook) { - flags = hook->flags; + if (hook->refcount) + flags = hook->flags; hook = hook->next; } verbose_observer = (flags & afb_hook_flag_global_vverbose) ? afb_hook_global_vverbose : NULL; @@ -1764,10 +1792,10 @@ struct afb_hook_global *afb_hook_create_global(int flags, struct afb_hook_global hook->closure = closure; /* record the hook */ - pthread_rwlock_wrlock(&rwlock); + pthread_mutex_lock(&mutex); hook->next = list_of_global_hooks; list_of_global_hooks = hook; - pthread_rwlock_unlock(&rwlock); + pthread_mutex_unlock(&mutex); /* update hooking */ update_global(); @@ -1778,36 +1806,45 @@ struct afb_hook_global *afb_hook_create_global(int flags, struct afb_hook_global struct afb_hook_global *afb_hook_addref_global(struct afb_hook_global *hook) { - pthread_rwlock_wrlock(&rwlock); - hook->refcount++; - pthread_rwlock_unlock(&rwlock); + __atomic_add_fetch(&hook->refcount, 1, __ATOMIC_RELAXED); return hook; } -void afb_hook_unref_global(struct afb_hook_global *hook) +static void hook_clean_global() { - struct afb_hook_global **prv; + struct afb_hook_global **prv, *hook, *head; - if (hook) { - pthread_rwlock_wrlock(&rwlock); - if (--hook->refcount) - hook = NULL; - else { - /* unlink */ - prv = &list_of_global_hooks; - while (*prv && *prv != hook) + if (pthread_rwlock_trywrlock(&rwlock) == 0) { + /* unlink under mutex */ + head = NULL; + pthread_mutex_lock(&mutex); + prv = &list_of_global_hooks; + while ((hook = *prv)) { + if (hook->refcount) prv = &(*prv)->next; - if(*prv) + else { *prv = hook->next; + hook->next = head; + head = hook; + } } + pthread_mutex_unlock(&mutex); pthread_rwlock_unlock(&rwlock); - if (hook) { - /* free */ - free(hook); - /* update hooking */ - update_global(); + /* free found hooks */ + while((hook = head)) { + head = hook->next; + free(hook); } } } +void afb_hook_unref_global(struct afb_hook_global *hook) +{ + if (hook && !__atomic_sub_fetch(&hook->refcount, 1, __ATOMIC_RELAXED)) { + /* update hooking */ + update_global(); + hook_clean_global(); + } +} + |