zircon/third_party/ulib/musl/src/exit/__cxa_thread_atexit.c

// Copyright 2017 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include <stdint.h>
#include <stdlib.h>
#include <threads.h>

#include "libc.h"
#include "threads_impl.h"

struct tls_dtor {
  struct tls_dtor* next;
  void (*func)(void*);
  void* arg;
};

void __tls_run_dtors(void) {
  struct tls_dtor* cur;
  thrd_t self = __thrd_current();
  while (self->tls_dtors) {
    cur = self->tls_dtors;
    self->tls_dtors = self->tls_dtors->next;
    cur->func(cur->arg);
    free(cur);
  }
}

int __cxa_thread_atexit_impl(void (*func)(void*), void* arg, void* dso) {
  struct tls_dtor* new_td = malloc(sizeof(struct tls_dtor));
  if (!new_td) {
    return -1;
  }
  new_td->func = func;
  new_td->arg = arg;

  // Prepend function to the list, the thread local destructors have to be
  // called in an order determined by the sequenced-before rule according to
  // C++ standard [basic.start.term].
  thrd_t self = __thrd_current();
  new_td->next = self->tls_dtors;
  self->tls_dtors = new_td;

  return 0;
}