/*

 * Copyright © 2007  Chris Wilson

 * Copyright © 2009,2010  Red Hat, Inc.

 * Copyright © 2011,2012  Google, Inc.

 *

 *  This is part of HarfBuzz, a text shaping library.

 *

 * Permission is hereby granted, without written agreement and without

 * license or royalty fees, to use, copy, modify, and distribute this

 * software and its documentation for any purpose, provided that the

 * above copyright notice and the following two paragraphs appear in

 * all copies of this software.

 *

 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR

 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES

 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN

 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH

 * DAMAGE.

 *

 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,

 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND

 * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS

 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO

 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.

 *

 * Contributor(s):

 *	Chris Wilson <chris@chris-wilson.co.uk>

 * Red Hat Author(s): Behdad Esfahbod

 * Google Author(s): Behdad Esfahbod

 */

#ifndef HB_ATOMIC_PRIVATE_HH

#define HB_ATOMIC_PRIVATE_HH

#include "hb-private.hh"

/* atomic_int */

/* We need external help for these */

#if defined(hb_atomic_int_impl_add) \

 && defined(hb_atomic_ptr_impl_get) \

 && defined(hb_atomic_ptr_impl_cmpexch)

/* Defined externally, i.e. in config.h; must have typedef'ed hb_atomic_int_impl_t as well. */

#elif !defined(HB_NO_MT) && (defined(_WIN32) || defined(__CYGWIN__))

#include <windows.h>

/* MinGW has a convoluted history of supporting MemoryBarrier

 * properly.  As such, define a function to wrap the whole

 * thing. */

static inline void _HBMemoryBarrier (void) {

#if !defined(MemoryBarrier)

  long dummy = 0;

  InterlockedExchange (&dummy, 1);

#else

  MemoryBarrier ();

#endif

}

typedef LONG hb_atomic_int_impl_t;

#define HB_ATOMIC_INT_IMPL_INIT(V) (V)

#define hb_atomic_int_impl_add(AI, V)		InterlockedExchangeAdd (&(AI), (V))

#define hb_atomic_ptr_impl_get(P)		(_HBMemoryBarrier (), (void *) *(P))

#define hb_atomic_ptr_impl_cmpexch(P,O,N)	(InterlockedCompareExchangePointer ((void **) (P), (void *) (N), (void *) (O)) == (void *) (O))

#elif !defined(HB_NO_MT) && defined(__APPLE__)

#include <libkern/OSAtomic.h>

#ifdef __MAC_OS_X_MIN_REQUIRED

#include <AvailabilityMacros.h>

#elif defined(__IPHONE_OS_MIN_REQUIRED)

#include <Availability.h>

#endif

typedef int32_t hb_atomic_int_impl_t;

#define HB_ATOMIC_INT_IMPL_INIT(V) (V)

#define hb_atomic_int_impl_add(AI, V)		(OSAtomicAdd32Barrier ((V), &(AI)) - (V))

#define hb_atomic_ptr_impl_get(P)		(OSMemoryBarrier (), (void *) *(P))

#if (MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_4 || __IPHONE_VERSION_MIN_REQUIRED >= 20100)

#define hb_atomic_ptr_impl_cmpexch(P,O,N)	OSAtomicCompareAndSwapPtrBarrier ((void *) (O), (void *) (N), (void **) (P))

#else

#if __ppc64__ || __x86_64__ || __aarch64__

#define hb_atomic_ptr_impl_cmpexch(P,O,N)	OSAtomicCompareAndSwap64Barrier ((int64_t) (O), (int64_t) (N), (int64_t*) (P))

#else

#define hb_atomic_ptr_impl_cmpexch(P,O,N)	OSAtomicCompareAndSwap32Barrier ((int32_t) (O), (int32_t) (N), (int32_t*) (P))

#endif

#endif

#elif !defined(HB_NO_MT) && defined(HAVE_INTEL_ATOMIC_PRIMITIVES)

typedef int hb_atomic_int_impl_t;

#define HB_ATOMIC_INT_IMPL_INIT(V) (V)

#define hb_atomic_int_impl_add(AI, V)		__sync_fetch_and_add (&(AI), (V))

#define hb_atomic_ptr_impl_get(P)		(void *) (__sync_synchronize (), *(P))

#define hb_atomic_ptr_impl_cmpexch(P,O,N)	__sync_bool_compare_and_swap ((P), (O), (N))

#elif !defined(HB_NO_MT) && defined(HAVE_SOLARIS_ATOMIC_OPS)

#include <atomic.h>

#include <mbarrier.h>

typedef unsigned int hb_atomic_int_impl_t;

#define HB_ATOMIC_INT_IMPL_INIT(V) (V)

#define hb_atomic_int_impl_add(AI, V)		( ({__machine_rw_barrier ();}), atomic_add_int_nv (&(AI), (V)) - (V))

#define hb_atomic_ptr_impl_get(P)		( ({__machine_rw_barrier ();}), (void *) *(P))

#define hb_atomic_ptr_impl_cmpexch(P,O,N)	( ({__machine_rw_barrier ();}), atomic_cas_ptr ((void **) (P), (void *) (O), (void *) (N)) == (void *) (O) ? true : false)

#elif !defined(HB_NO_MT) && defined(_AIX) && defined(__IBMCPP__)

#include <builtins.h>

static inline int _hb_fetch_and_add(volatile int* AI, unsigned int V) {

  __lwsync();

  int result = __fetch_and_add(AI, V);

  __isync();

  return result;

}

static inline int _hb_compare_and_swaplp(volatile long* P, long O, long N) {

  __sync();

  int result = __compare_and_swaplp (P, &O, N);

  __sync();

  return result;

}

typedef int hb_atomic_int_impl_t;

#define HB_ATOMIC_INT_IMPL_INIT(V) (V)

#define hb_atomic_int_impl_add(AI, V)           _hb_fetch_and_add (&(AI), (V))

#define hb_atomic_ptr_impl_get(P)               (__sync(), (void *) *(P))

#define hb_atomic_ptr_impl_cmpexch(P,O,N)       _hb_compare_and_swaplp ((long*)(P), (long)(O), (long)(N))

#elif !defined(HB_NO_MT)

#define HB_ATOMIC_INT_NIL 1 /* Warn that fallback implementation is in use. */

typedef volatile int hb_atomic_int_impl_t;

#define HB_ATOMIC_INT_IMPL_INIT(V) (V)

#define hb_atomic_int_impl_add(AI, V)		(((AI) += (V)) - (V))

#define hb_atomic_ptr_impl_get(P)		((void *) *(P))

#define hb_atomic_ptr_impl_cmpexch(P,O,N)	(* (void * volatile *) (P) == (void *) (O) ? (* (void * volatile *) (P) = (void *) (N), true) : false)

#else /* HB_NO_MT */

typedef int hb_atomic_int_impl_t;

#define HB_ATOMIC_INT_IMPL_INIT(V)		(V)

#define hb_atomic_int_impl_add(AI, V)		(((AI) += (V)) - (V))

#define hb_atomic_ptr_impl_get(P)		((void *) *(P))

#define hb_atomic_ptr_impl_cmpexch(P,O,N)	(* (void **) (P) == (void *) (O) ? (* (void **) (P) = (void *) (N), true) : false)

#endif

#define HB_ATOMIC_INT_INIT(V)		{HB_ATOMIC_INT_IMPL_INIT(V)}

struct hb_atomic_int_t

{

  hb_atomic_int_impl_t v;

  inline void set_unsafe (int v_) { v = v_; }

  inline int get_unsafe (void) const { return v; }

  inline int inc (void) { return hb_atomic_int_impl_add (const_cast<hb_atomic_int_impl_t &> (v),  1); }

  inline int dec (void) { return hb_atomic_int_impl_add (const_cast<hb_atomic_int_impl_t &> (v), -1); }

};

#define hb_atomic_ptr_get(P) hb_atomic_ptr_impl_get(P)

#define hb_atomic_ptr_cmpexch(P,O,N) hb_atomic_ptr_impl_cmpexch((P),(O),(N))

#endif /* HB_ATOMIC_PRIVATE_HH */