/*

 * libusb synchronization using POSIX Threads

 *

 * Copyright © 2011 Vitali Lovich <vlovich@aliph.com>

 * Copyright © 2011 Peter Stuge <peter@stuge.se>

 *

 * 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 2.1 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 library; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

#include "libusbi.h"

#include <errno.h>

#include <limits.h>

#if defined(__ANDROID__)

# include <unistd.h>

#elif defined(__HAIKU__)

# include <os/kernel/OS.h>

#elif defined(__linux__)

# include <sys/syscall.h>

# include <unistd.h>

#elif defined(__NetBSD__)

# include <lwp.h>

#elif defined(__OpenBSD__)

# include <unistd.h>

#elif defined(__sun__)

# include <sys/lwp.h>

#endif

void usbi_cond_init(pthread_cond_t *cond)

{

#ifdef HAVE_PTHREAD_CONDATTR_SETCLOCK

  pthread_condattr_t condattr;

  PTHREAD_CHECK(pthread_condattr_init(&condattr));

  PTHREAD_CHECK(pthread_condattr_setclock(&condattr, CLOCK_MONOTONIC));

  PTHREAD_CHECK(pthread_cond_init(cond, &condattr));

  PTHREAD_CHECK(pthread_condattr_destroy(&condattr));

#else

  PTHREAD_CHECK(pthread_cond_init(cond, NULL));

#endif

}

int usbi_cond_timedwait(pthread_cond_t *cond,

  pthread_mutex_t *mutex, const struct timeval *tv)

{

  struct timespec timeout;

  int r;

#ifdef HAVE_PTHREAD_CONDATTR_SETCLOCK

  usbi_get_monotonic_time(&timeout);

#else

  usbi_get_real_time(&timeout);

#endif

  timeout.tv_sec += tv->tv_sec;

  timeout.tv_nsec += tv->tv_usec * 1000L;

  if (timeout.tv_nsec >= NSEC_PER_SEC) {

    timeout.tv_nsec -= NSEC_PER_SEC;

    timeout.tv_sec++;

  }

  r = pthread_cond_timedwait(cond, mutex, &timeout);

  if (r == 0)

    return 0;

  else if (r == ETIMEDOUT)

    return LIBUSB_ERROR_TIMEOUT;

  else

    return LIBUSB_ERROR_OTHER;

}

unsigned long usbi_get_tid(void)

{

  static _Thread_local unsigned long tl_tid;

  unsigned long tid;

  if (tl_tid)

    return tl_tid;

#if defined(__ANDROID__)

  tid = (unsigned long)gettid();

#elif defined(__APPLE__)

#ifdef HAVE_PTHREAD_THREADID_NP

  uint64_t thread_id;

  if (pthread_threadid_np(NULL, &thread_id) == 0)

    tid = (unsigned long)thread_id;

  else

    tid = ULONG_MAX;

#else

  tid = (unsigned long)pthread_mach_thread_np(pthread_self());

#endif

#elif defined(__HAIKU__)

  tid = (unsigned long)get_pthread_thread_id(pthread_self());

#elif defined(__linux__)

  tid = (unsigned long)syscall(SYS_gettid);

#elif defined(__NetBSD__)

  tid = (unsigned long)_lwp_self();

#elif defined(__OpenBSD__)

  tid = (unsigned long)getthrid();

#elif defined(__sun__)

  tid = (unsigned long)_lwp_self();

#else

  tid = ULONG_MAX;

#endif

  if (tid == ULONG_MAX) {

    /* If we don't have a thread ID, at least return a unique

     * value that can be used to distinguish individual

     * threads. */

    tid = (unsigned long)(uintptr_t)pthread_self();

  }

  return tl_tid = tid;

}