/*
- * Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 2016-2018 The OpenSSL Project Authors. All Rights Reserved.
*
- * Licensed under the OpenSSL license (the "License"). You may not use
+ * Licensed under the Apache License 2.0 (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
#ifndef HEADER_INTERNAL_REFCOUNT_H
# define HEADER_INTERNAL_REFCOUNT_H
-# if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L \
- && !defined(__STDC_NO_ATOMICS__)
-# include <stdatomic.h>
-# define HAVE_C11_ATOMICS
+/* Used to checking reference counts, most while doing perl5 stuff :-) */
+# if defined(OPENSSL_NO_STDIO)
+# if defined(REF_PRINT)
+# error "REF_PRINT requires stdio"
+# endif
# endif
-# if defined(HAVE_C11_ATOMICS) && defined(ATOMIC_INT_LOCK_FREE) \
- && ATOMIC_INT_LOCK_FREE > 0
+# ifndef OPENSSL_DEV_NO_ATOMICS
+# if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L \
+ && !defined(__STDC_NO_ATOMICS__)
+# include <stdatomic.h>
+# define HAVE_C11_ATOMICS
+# endif
-# define HAVE_ATOMICS 1
+# if defined(HAVE_C11_ATOMICS) && defined(ATOMIC_INT_LOCK_FREE) \
+ && ATOMIC_INT_LOCK_FREE > 0
-typedef _Atomic int CRYPTO_REF_COUNT;
+# define HAVE_ATOMICS 1
-static ossl_inline int CRYPTO_GET_REF(_Atomic int *val, int *ret, void *lock)
-{
- *ret = atomic_fetch_add_explicit(val, 0, memory_order_relaxed);
- return 1;
-}
+typedef _Atomic int CRYPTO_REF_COUNT;
-static ossl_inline int CRYPTO_UP_REF(_Atomic int *val, int *ret, void *lock)
+static inline int CRYPTO_UP_REF(_Atomic int *val, int *ret, void *lock)
{
*ret = atomic_fetch_add_explicit(val, 1, memory_order_relaxed) + 1;
return 1;
}
-static ossl_inline int CRYPTO_DOWN_REF(_Atomic int *val, int *ret, void *lock)
+/*
+ * Changes to shared structure other than reference counter have to be
+ * serialized. And any kind of serialization implies a release fence. This
+ * means that by the time reference counter is decremented all other
+ * changes are visible on all processors. Hence decrement itself can be
+ * relaxed. In case it hits zero, object will be destructed. Since it's
+ * last use of the object, destructor programmer might reason that access
+ * to mutable members doesn't have to be serialized anymore, which would
+ * otherwise imply an acquire fence. Hence conditional acquire fence...
+ */
+static inline int CRYPTO_DOWN_REF(_Atomic int *val, int *ret, void *lock)
{
- *ret = atomic_fetch_sub_explicit(val, 1, memory_order_release) - 1;
+ *ret = atomic_fetch_sub_explicit(val, 1, memory_order_relaxed) - 1;
if (*ret == 0)
atomic_thread_fence(memory_order_acquire);
return 1;
}
-# elif defined(__GNUC__) && defined(__ATOMIC_RELAXED) && __GCC_ATOMIC_INT_LOCK_FREE > 0
+# elif defined(__GNUC__) && defined(__ATOMIC_RELAXED) && __GCC_ATOMIC_INT_LOCK_FREE > 0
-# define HAVE_ATOMICS 1
+# define HAVE_ATOMICS 1
typedef int CRYPTO_REF_COUNT;
-static ossl_inline int CRYPTO_GET_REF(int *val, int *ret, void *lock)
+static __inline__ int CRYPTO_UP_REF(int *val, int *ret, void *lock)
{
- *ret = __atomic_fetch_add(val, 0, __ATOMIC_RELAXED);
+ *ret = __atomic_fetch_add(val, 1, __ATOMIC_RELAXED) + 1;
return 1;
}
-static ossl_inline int CRYPTO_UP_REF(int *val, int *ret, void *lock)
+static __inline__ int CRYPTO_DOWN_REF(int *val, int *ret, void *lock)
{
- *ret = __atomic_fetch_add(val, 1, __ATOMIC_RELAXED) + 1;
+ *ret = __atomic_fetch_sub(val, 1, __ATOMIC_RELAXED) - 1;
+ if (*ret == 0)
+ __atomic_thread_fence(__ATOMIC_ACQUIRE);
+ return 1;
+}
+
+# elif defined(_MSC_VER) && _MSC_VER>=1200
+
+# define HAVE_ATOMICS 1
+
+typedef volatile int CRYPTO_REF_COUNT;
+
+# if (defined(_M_ARM) && _M_ARM>=7 && !defined(_WIN32_WCE)) || defined(_M_ARM64)
+# include <intrin.h>
+# if defined(_M_ARM64) && !defined(_ARM_BARRIER_ISH)
+# define _ARM_BARRIER_ISH _ARM64_BARRIER_ISH
+# endif
+
+static __inline int CRYPTO_UP_REF(volatile int *val, int *ret, void *lock)
+{
+ *ret = _InterlockedExchangeAdd_nf(val, 1) + 1;
return 1;
}
-static ossl_inline int CRYPTO_DOWN_REF(int *val, int *ret, void *lock)
+static __inline int CRYPTO_DOWN_REF(volatile int *val, int *ret, void *lock)
{
- *ret = __atomic_fetch_sub(val, 1, __ATOMIC_RELEASE) - 1;
+ *ret = _InterlockedExchangeAdd_nf(val, -1) - 1;
if (*ret == 0)
- __atomic_thread_fence(__ATOMIC_ACQUIRE);
+ __dmb(_ARM_BARRIER_ISH);
+ return 1;
+}
+# else
+# if !defined(_WIN32_WCE)
+# pragma intrinsic(_InterlockedExchangeAdd)
+# else
+# if _WIN32_WCE >= 0x600
+ extern long __cdecl _InterlockedExchangeAdd(long volatile*, long);
+# else
+ // under Windows CE we still have old-style Interlocked* functions
+ extern long __cdecl InterlockedExchangeAdd(long volatile*, long);
+# define _InterlockedExchangeAdd InterlockedExchangeAdd
+# endif
+# endif
+
+static __inline int CRYPTO_UP_REF(volatile int *val, int *ret, void *lock)
+{
+ *ret = _InterlockedExchangeAdd(val, 1) + 1;
return 1;
}
-# else
+static __inline int CRYPTO_DOWN_REF(volatile int *val, int *ret, void *lock)
+{
+ *ret = _InterlockedExchangeAdd(val, -1) - 1;
+ return 1;
+}
+# endif
+
+# endif
+# endif /* !OPENSSL_DEV_NO_ATOMICS */
+
+/*
+ * All the refcounting implementations above define HAVE_ATOMICS, so if it's
+ * still undefined here (such as when OPENSSL_DEV_NO_ATMOICS is defined), it
+ * means we need to implement a fallback. This fallback uses locks.
+ */
+# ifndef HAVE_ATOMICS
typedef int CRYPTO_REF_COUNT;
-# define CRYPTO_GET_REF(val, ret, lock) CRYPTO_atomic_add(val, 0, ret, lock)
# define CRYPTO_UP_REF(val, ret, lock) CRYPTO_atomic_add(val, 1, ret, lock)
# define CRYPTO_DOWN_REF(val, ret, lock) CRYPTO_atomic_add(val, -1, ret, lock)
# endif
+
+# if !defined(NDEBUG) && !defined(OPENSSL_NO_STDIO)
+# define REF_ASSERT_ISNT(test) \
+ (void)((test) ? (OPENSSL_die("refcount error", __FILE__, __LINE__), 1) : 0)
+# else
+# define REF_ASSERT_ISNT(i)
+# endif
+
+# ifdef REF_PRINT
+# define REF_PRINT_COUNT(a, b) \
+ fprintf(stderr, "%p:%4d:%s\n", b, b->references, a)
+# else
+# define REF_PRINT_COUNT(a, b)
+# endif
+
#endif
projects / openssl.git / blobdiff