#ifndef HEADER_CURL_EASY_LOCK_H

#define HEADER_CURL_EASY_LOCK_H

/***************************************************************************

 *                                  _   _ ____  _

 *  Project                     ___| | | |  _ \| |

 *                             / __| | | | |_) | |

 *                            | (__| |_| |  _ <| |___

 *                             \___|\___/|_| \_\_____|

 *

 * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.

 *

 * This software is licensed as described in the file COPYING, which

 * you should have received as part of this distribution. The terms

 * are also available at https://curl.se/docs/copyright.html.

 *

 * You may opt to use, copy, modify, merge, publish, distribute and/or sell

 * copies of the Software, and permit persons to whom the Software is

 * furnished to do so, under the terms of the COPYING file.

 *

 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY

 * KIND, either express or implied.

 *

 * SPDX-License-Identifier: curl

 *

 ***************************************************************************/

#include "curl_setup.h"

#define GLOBAL_INIT_IS_THREADSAFE

#if defined(_WIN32_WINNT) && _WIN32_WINNT >= 0x600

#ifdef __MINGW32__

#ifndef SRWLOCK_INIT

#define SRWLOCK_INIT NULL

#endif

#endif /* __MINGW32__ */

#define curl_simple_lock SRWLOCK

#define CURL_SIMPLE_LOCK_INIT SRWLOCK_INIT

#define curl_simple_lock_lock(m) AcquireSRWLockExclusive(m)

#define curl_simple_lock_unlock(m) ReleaseSRWLockExclusive(m)

#elif defined(HAVE_ATOMIC) && defined(HAVE_STDATOMIC_H)

#include <stdatomic.h>

#if defined(HAVE_SCHED_YIELD)

#include <sched.h>

#endif

#define curl_simple_lock atomic_int

#define CURL_SIMPLE_LOCK_INIT 0

/* a clang-thing */

#ifndef __has_builtin

#define __has_builtin(x) 0

#endif

#ifndef __INTEL_COMPILER

/* The Intel compiler tries to look like GCC *and* clang *and* lies in its

   __has_builtin() function, so override it. */

/* if GCC on i386/x86_64 or if the built-in is present */

#if ( (defined(__GNUC__) && !defined(__clang__)) &&     \

      (defined(__i386__) || defined(__x86_64__))) ||    \

  __has_builtin(__builtin_ia32_pause)

#define HAVE_BUILTIN_IA32_PAUSE

#endif

#endif

static inline void curl_simple_lock_lock(curl_simple_lock *lock)

{

  for(;;) {

    if(!atomic_exchange_explicit(lock, true, memory_order_acquire))

      break;

    /* Reduce cache coherency traffic */

    while(atomic_load_explicit(lock, memory_order_relaxed)) {

      /* Reduce load (not mandatory) */

#ifdef HAVE_BUILTIN_IA32_PAUSE

      __builtin_ia32_pause();

#elif defined(__aarch64__)

      __asm__ volatile("yield" ::: "memory");

#elif defined(HAVE_SCHED_YIELD)

      sched_yield();

#endif

    }

  }

}

Unexecuted instantiation: easy.c:curl_simple_lock_lock

Unexecuted instantiation: hostip.c:curl_simple_lock_lock

static inline void curl_simple_lock_unlock(curl_simple_lock *lock)

{

  atomic_store_explicit(lock, false, memory_order_release);

}

Unexecuted instantiation: easy.c:curl_simple_lock_unlock

Unexecuted instantiation: hostip.c:curl_simple_lock_unlock

#elif defined(USE_THREADS_POSIX) && defined(HAVE_PTHREAD_H)

#include <pthread.h>

#define curl_simple_lock pthread_mutex_t

#define CURL_SIMPLE_LOCK_INIT PTHREAD_MUTEX_INITIALIZER

#define curl_simple_lock_lock(m) pthread_mutex_lock(m)

#define curl_simple_lock_unlock(m) pthread_mutex_unlock(m)

#else

#undef  GLOBAL_INIT_IS_THREADSAFE

#endif

#endif /* HEADER_CURL_EASY_LOCK_H */