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/**
* Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: Apache-2.0.
*/
#include <aws/common/ref_count.h>
#include <aws/common/clock.h>
#include <aws/common/condition_variable.h>
#include <aws/common/mutex.h>
void aws_ref_count_init(struct aws_ref_count *ref_count, void *object, aws_simple_completion_callback *on_zero_fn) {
aws_atomic_init_int(&ref_count->ref_count, 1);
ref_count->object = object;
ref_count->on_zero_fn = on_zero_fn;
}
void *aws_ref_count_acquire(struct aws_ref_count *ref_count) {
aws_atomic_fetch_add(&ref_count->ref_count, 1);
return ref_count->object;
}
size_t aws_ref_count_release(struct aws_ref_count *ref_count) {
size_t old_value = aws_atomic_fetch_sub(&ref_count->ref_count, 1);
AWS_ASSERT(old_value > 0 && "refcount has gone negative");
if (old_value == 1) {
ref_count->on_zero_fn(ref_count->object);
}
return old_value - 1;
}
static struct aws_condition_variable s_global_thread_signal = AWS_CONDITION_VARIABLE_INIT;
static struct aws_mutex s_global_thread_lock = AWS_MUTEX_INIT;
static uint32_t s_global_thread_count = 0;
void aws_global_thread_creator_increment(void) {
aws_mutex_lock(&s_global_thread_lock);
++s_global_thread_count;
aws_mutex_unlock(&s_global_thread_lock);
}
void aws_global_thread_creator_decrement(void) {
bool signal = false;
aws_mutex_lock(&s_global_thread_lock);
AWS_ASSERT(s_global_thread_count != 0 && "global tracker has gone negative");
--s_global_thread_count;
if (s_global_thread_count == 0) {
signal = true;
}
aws_mutex_unlock(&s_global_thread_lock);
if (signal) {
aws_condition_variable_notify_all(&s_global_thread_signal);
}
}
static bool s_thread_count_zero_pred(void *user_data) {
(void)user_data;
return s_global_thread_count == 0;
}
void aws_global_thread_creator_shutdown_wait(void) {
aws_mutex_lock(&s_global_thread_lock);
aws_condition_variable_wait_pred(&s_global_thread_signal, &s_global_thread_lock, s_thread_count_zero_pred, NULL);
aws_mutex_unlock(&s_global_thread_lock);
}
int aws_global_thread_creator_shutdown_wait_for(uint32_t wait_timeout_in_seconds) {
int64_t wait_time_in_nanos =
aws_timestamp_convert(wait_timeout_in_seconds, AWS_TIMESTAMP_SECS, AWS_TIMESTAMP_NANOS, NULL);
aws_mutex_lock(&s_global_thread_lock);
int result = aws_condition_variable_wait_for_pred(
&s_global_thread_signal, &s_global_thread_lock, wait_time_in_nanos, s_thread_count_zero_pred, NULL);
aws_mutex_unlock(&s_global_thread_lock);
return result;
}
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