/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-â
âvi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :viâ
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â Copyright 2022 Justine Alexandra Roberts Tunney                              â
â                                                                              â
â Permission to use, copy, modify, and/or distribute this software for         â
â any purpose with or without fee is hereby granted, provided that the         â
â above copyright notice and this permission notice appear in all copies.      â
â                                                                              â
â THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                â
â WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                â
â WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             â
â AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         â
â DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        â
â PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               â
â TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             â
â PERFORMANCE OF THIS SOFTWARE.                                                â
ââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââ*/
#include "libc/calls/calls.h"
#include "libc/calls/syscall_support-sysv.internal.h"
#include "libc/errno.h"
#include "libc/intrin/atomic.h"
#include "libc/thread/posixthread.internal.h"
#include "libc/thread/thread.h"

/**
 * Sends signal to thread.
 *
 * @return 0 on success, or errno on error
 * @raise ESRCH if `tid` was valid but no such thread existed
 * @raise EAGAIN if `RLIMIT_SIGPENDING` was exceeded
 * @raise EINVAL if `tid` or `sig` was invalid
 * @raise EPERM if permission was denied
 * @asyncsignalsafe
 */
errno_t pthread_kill(pthread_t thread, int sig) {
  int e, rc, tid;
  struct PosixThread *p;
  if (!(rc = pthread_getunique_np(thread, &tid))) {
    e = errno;
    p = (struct PosixThread *)thread;
    if (!__tkill(tid, sig, p->tib)) {
      rc = 0;
    } else {
      rc = errno;
      errno = e;
    }
  }
  return rc;
}
