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Diffstat (limited to 'pceplib/pcep_timers.c')
| -rw-r--r-- | pceplib/pcep_timers.c | 489 |
1 files changed, 489 insertions, 0 deletions
diff --git a/pceplib/pcep_timers.c b/pceplib/pcep_timers.c new file mode 100644 index 0000000..b0f3e70 --- /dev/null +++ b/pceplib/pcep_timers.c @@ -0,0 +1,489 @@ +/* + * This file is part of the PCEPlib, a PCEP protocol library. + * + * Copyright (C) 2020 Volta Networks https://voltanet.io/ + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public License + * along with this program. If not, see <https://www.gnu.org/licenses/>. + * + * Author : Brady Johnson <brady@voltanet.io> + * + */ + + +/* + * Implementation of public API timer functions. + */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include <limits.h> +#include <pthread.h> +#include <stddef.h> +#include <stdbool.h> +#include <string.h> + +#include "pcep_timers.h" +#include "pcep_utils_logging.h" +#include "pcep_utils_memory.h" +#include "pcep_utils_ordered_list.h" + +static pcep_timers_context *timers_context_ = NULL; +static int timer_id_ = 0; + + +/* simple compare method callback used by pcep_utils_ordered_list + * for ordered list insertion. */ +int timer_list_node_compare(void *list_entry, void *new_entry) +{ + /* return: + * < 0 if new_entry < list_entry + * == 0 if new_entry == list_entry (new_entry will be inserted after + * list_entry) > 0 if new_entry > list_entry */ + return ((pcep_timer *)new_entry)->expire_time + - ((pcep_timer *)list_entry)->expire_time; +} + + +/* simple compare method callback used by pcep_utils_ordered_list + * ordered_list_remove_first_node_equals2 to remove a timer based on + * its timer_id. */ +int timer_list_node_timer_id_compare(void *list_entry, void *new_entry) +{ + return ((pcep_timer *)new_entry)->timer_id + - ((pcep_timer *)list_entry)->timer_id; +} + +/* simple compare method callback used by pcep_utils_ordered_list + * ordered_list_remove_first_node_equals2 to remove a timer based on + * its address. */ +int timer_list_node_timer_ptr_compare(void *list_entry, void *new_entry) +{ + return ((char *)new_entry - (char *)list_entry); +} + +/* internal util method */ +static pcep_timers_context *create_timers_context_(void) +{ + if (timers_context_ == NULL) { + timers_context_ = pceplib_malloc(PCEPLIB_INFRA, + sizeof(pcep_timers_context)); + memset(timers_context_, 0, sizeof(pcep_timers_context)); + timers_context_->active = false; + } + + return timers_context_; +} + + +/* Internal util function */ +static bool initialize_timers_common(timer_expire_handler expire_handler) +{ + if (expire_handler == NULL) { + /* Cannot have a NULL handler function */ + return false; + } + + timers_context_ = create_timers_context_(); + + if (timers_context_->active == true) { + /* already initialized */ + return false; + } + + timers_context_->active = true; + timers_context_->timer_list = + ordered_list_initialize(timer_list_node_compare); + timers_context_->expire_handler = expire_handler; + + if (pthread_mutex_init(&(timers_context_->timer_list_lock), NULL) + != 0) { + pcep_log( + LOG_ERR, + "%s: ERROR initializing timers, cannot initialize the mutex", + __func__); + return false; + } + + return true; +} + +bool initialize_timers(timer_expire_handler expire_handler) +{ + if (initialize_timers_common(expire_handler) == false) { + return false; + } + + if (pthread_create(&(timers_context_->event_loop_thread), NULL, + event_loop, timers_context_)) { + pcep_log( + LOG_ERR, + "%s: ERROR initializing timers, cannot initialize the thread", + __func__); + return false; + } + + return true; +} + +bool initialize_timers_external_infra( + timer_expire_handler expire_handler, void *external_timer_infra_data, + ext_timer_create timer_create_func, ext_timer_cancel timer_cancel_func, + ext_pthread_create_callback thread_create_func) +{ + if (initialize_timers_common(expire_handler) == false) { + return false; + } + + if (thread_create_func != NULL) { + if (thread_create_func(&(timers_context_->event_loop_thread), + NULL, event_loop, timers_context_, + "pceplib_timers")) { + pcep_log( + LOG_ERR, + "%s: Cannot initialize external timers thread.", + __func__); + return false; + } + } else { + if (pthread_create(&(timers_context_->event_loop_thread), NULL, + event_loop, timers_context_)) { + pcep_log( + LOG_ERR, + "%s: ERROR initializing timers, cannot initialize the thread", + __func__); + return false; + } + } + + timers_context_->external_timer_infra_data = external_timer_infra_data; + timers_context_->timer_create_func = timer_create_func; + timers_context_->timer_cancel_func = timer_cancel_func; + + return true; +} + +/* + * This function is only used to tear_down the timer data. + * Only the timer data is deleted, not the list itself, + * which is deleted by ordered_list_destroy(). + */ +void free_all_timers(pcep_timers_context *timers_context) +{ + pthread_mutex_lock(&timers_context->timer_list_lock); + + ordered_list_node *timer_node = timers_context->timer_list->head; + + while (timer_node != NULL) { + if (timer_node->data != NULL) { + pceplib_free(PCEPLIB_INFRA, timer_node->data); + } + timer_node = timer_node->next_node; + } + + pthread_mutex_unlock(&timers_context->timer_list_lock); +} + + +bool teardown_timers() +{ + if (timers_context_ == NULL) { + pcep_log( + LOG_WARNING, + "%s: Trying to teardown the timers, but they are not initialized", + __func__); + return false; + } + + if (timers_context_->active == false) { + pcep_log( + LOG_WARNING, + "%s: Trying to teardown the timers, but they are not active", + __func__); + return false; + } + + timers_context_->active = false; + if (timers_context_->event_loop_thread != 0) { + /* TODO this does not build + * Instead of calling pthread_join() which could block if the + thread + * is blocked, try joining for at most 1 second. + struct timespec ts; + clock_gettime(CLOCK_REALTIME, &ts); + ts.tv_sec += 1; + int retval = + pthread_timedjoin_np(timers_context_->event_loop_thread, NULL, + &ts); if (retval != 0) + { + pcep_log(LOG_WARNING, "%s: thread did not stop after 1 + second waiting on it.", __func__); + } + */ + pthread_join(timers_context_->event_loop_thread, NULL); + } + + free_all_timers(timers_context_); + ordered_list_destroy(timers_context_->timer_list); + + if (pthread_mutex_destroy(&(timers_context_->timer_list_lock)) != 0) { + pcep_log( + LOG_WARNING, + "%s: Trying to teardown the timers, cannot destroy the mutex", + __func__); + } + + pceplib_free(PCEPLIB_INFRA, timers_context_); + timers_context_ = NULL; + + return true; +} + + +int get_next_timer_id() +{ + if (timer_id_ == INT_MAX) { + timer_id_ = 0; + } + + return timer_id_++; +} + +int create_timer(uint16_t sleep_seconds, void *data) +{ + if (timers_context_ == NULL) { + pcep_log( + LOG_WARNING, + "%s: Trying to create a timer: the timers have not been initialized", + __func__); + return -1; + } + + pcep_timer *timer = pceplib_malloc(PCEPLIB_INFRA, sizeof(pcep_timer)); + memset(timer, 0, sizeof(pcep_timer)); + timer->data = data; + timer->sleep_seconds = sleep_seconds; + timer->expire_time = time(NULL) + sleep_seconds; + + pthread_mutex_lock(&timers_context_->timer_list_lock); + timer->timer_id = get_next_timer_id(); + + /* implemented in pcep_utils_ordered_list.c */ + if (ordered_list_add_node(timers_context_->timer_list, timer) == NULL) { + pceplib_free(PCEPLIB_INFRA, timer); + pthread_mutex_unlock(&timers_context_->timer_list_lock); + pcep_log( + LOG_WARNING, + "%s: Trying to create a timer, cannot add the timer to the timer list", + __func__); + + return -1; + } + + pthread_mutex_unlock(&timers_context_->timer_list_lock); + + if (timers_context_->timer_create_func) { + timers_context_->timer_create_func( + timers_context_->external_timer_infra_data, + &timer->external_timer, sleep_seconds, timer); + } + + return timer->timer_id; +} + + +bool cancel_timer(int timer_id) +{ + static pcep_timer compare_timer; + + if (timers_context_ == NULL) { + pcep_log( + LOG_WARNING, + "%s: Trying to cancel a timer: the timers have not been initialized", + __func__); + return false; + } + + pthread_mutex_lock(&timers_context_->timer_list_lock); + + compare_timer.timer_id = timer_id; + pcep_timer *timer_toRemove = ordered_list_remove_first_node_equals2( + timers_context_->timer_list, &compare_timer, + timer_list_node_timer_id_compare); + if (timer_toRemove == NULL) { + pthread_mutex_unlock(&timers_context_->timer_list_lock); + pcep_log( + LOG_WARNING, + "%s: Trying to cancel a timer [%d] that does not exist", + __func__, timer_id); + return false; + } + + pthread_mutex_unlock(&timers_context_->timer_list_lock); + + if (timers_context_->timer_cancel_func) { + timers_context_->timer_cancel_func( + &timer_toRemove->external_timer); + } + + pceplib_free(PCEPLIB_INFRA, timer_toRemove); + + return true; +} + + +bool reset_timer(int timer_id) +{ + static pcep_timer compare_timer; + + if (timers_context_ == NULL) { + pcep_log( + LOG_WARNING, + "%s: Trying to reset a timer: the timers have not been initialized", + __func__); + + return false; + } + + pthread_mutex_lock(&timers_context_->timer_list_lock); + + compare_timer.timer_id = timer_id; + ordered_list_node *timer_to_reset_node = + ordered_list_find2(timers_context_->timer_list, &compare_timer, + timer_list_node_timer_id_compare); + if (timer_to_reset_node == NULL) { + pthread_mutex_unlock(&timers_context_->timer_list_lock); + pcep_log(LOG_WARNING, + "%s: Trying to reset a timer node that does not exist", + __func__); + + return false; + } + + pcep_timer *timer_to_reset = timer_to_reset_node->data; + if (timer_to_reset == NULL) { + pthread_mutex_unlock(&timers_context_->timer_list_lock); + pcep_log(LOG_WARNING, + "%s: Trying to reset a timer that does not exist", + __func__); + + return false; + } + + /* First check if the timer to reset already has the same expire time, + * which means multiple reset_timer() calls were made on the same timer + * in the same second */ + time_t expire_time = time(NULL) + timer_to_reset->sleep_seconds; + if (timer_to_reset->expire_time == expire_time) { + pthread_mutex_unlock(&timers_context_->timer_list_lock); + return true; + } + + ordered_list_remove_node2(timers_context_->timer_list, + timer_to_reset_node); + + timer_to_reset->expire_time = expire_time; + if (ordered_list_add_node(timers_context_->timer_list, timer_to_reset) + == NULL) { + pceplib_free(PCEPLIB_INFRA, timer_to_reset); + pthread_mutex_unlock(&timers_context_->timer_list_lock); + pcep_log( + LOG_WARNING, + "%s: Trying to reset a timer, cannot add the timer to the timer list", + __func__); + + return false; + } + + pthread_mutex_unlock(&timers_context_->timer_list_lock); + + if (timers_context_->timer_cancel_func) { + /* Keeping this log for now, since in older versions of FRR the + * timer cancellation was blocking. This allows us to see how + * long the it takes.*/ + pcep_log(LOG_DEBUG, "%s: Resetting timer [%d] with callback", + __func__, timer_to_reset->timer_id); + timers_context_->timer_cancel_func( + &timer_to_reset->external_timer); + timer_to_reset->external_timer = NULL; + } + + if (timers_context_->timer_create_func) { + timers_context_->timer_create_func( + timers_context_->external_timer_infra_data, + &timer_to_reset->external_timer, + timer_to_reset->sleep_seconds, timer_to_reset); + /* Keeping this log for now, since in older versions of FRR the + * timer cancellation was blocking. This allows us to see how + * long the it takes.*/ + pcep_log(LOG_DEBUG, "%s: Reset timer [%d] with callback", + __func__, timer_to_reset->timer_id); + } + + return true; +} + + +void pceplib_external_timer_expire_handler(void *data) +{ + if (timers_context_ == NULL) { + pcep_log( + LOG_WARNING, + "%s: External timer expired but timers_context is not initialized", + __func__); + return; + } + + if (timers_context_->expire_handler == NULL) { + pcep_log( + LOG_WARNING, + "%s: External timer expired but expire_handler is not initialized", + __func__); + return; + } + + if (data == NULL) { + pcep_log(LOG_WARNING, + "%s: External timer expired with NULL data", __func__); + return; + } + + pcep_timer *timer = (pcep_timer *)data; + + pthread_mutex_lock(&timers_context_->timer_list_lock); + ordered_list_node *timer_node = + ordered_list_find2(timers_context_->timer_list, timer, + timer_list_node_timer_ptr_compare); + + /* Remove timer from list */ + if (timer_node) + ordered_list_remove_node2(timers_context_->timer_list, + timer_node); + + pthread_mutex_unlock(&timers_context_->timer_list_lock); + + /* Cannot continue if the timer does not exist */ + if (timer_node == NULL) { + pcep_log( + LOG_WARNING, + "%s: pceplib_external_timer_expire_handler timer [%p] id [%d] does not exist", + __func__, timer, timer->timer_id); + return; + } + + timers_context_->expire_handler(timer->data, timer->timer_id); + + pceplib_free(PCEPLIB_INFRA, timer); +} |