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Diffstat (limited to 'libparc/parc/concurrent/parc_AtomicUint8.h')
| -rwxr-xr-x | libparc/parc/concurrent/parc_AtomicUint8.h | 341 |
1 files changed, 341 insertions, 0 deletions
diff --git a/libparc/parc/concurrent/parc_AtomicUint8.h b/libparc/parc/concurrent/parc_AtomicUint8.h new file mode 100755 index 00000000..7434b93d --- /dev/null +++ b/libparc/parc/concurrent/parc_AtomicUint8.h @@ -0,0 +1,341 @@ +/* + * Copyright (c) 2017 Cisco and/or its affiliates. + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at: + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +/** + * @file parc_AtomicUint8.h + * @ingroup threading + * @brief An atomically updated 8-bit unsigned integer. + * + * <#Detailed Description#> + * + */ +#ifndef PARCLibrary_parc_AtomicUint8 +#define PARCLibrary_parc_AtomicUint8 +#include <stdbool.h> +#include <stdint.h> + +#include <parc/algol/parc_JSON.h> + +#ifdef PARCLibrary_DISABLE_ATOMICS +#include <pthread.h> +struct PARCAtomicUint8; +typedef struct PARCAtomicUint8 PARCAtomicUint8; +#else +typedef uint8_t PARCAtomicUint8; +#endif + + +PARCAtomicUint8 *parcAtomicInteger_CreateUint8(uint8_t value); + +uint8_t parcAtomicUint8_AddImpl(PARCAtomicUint8 *value, uint8_t addend); + +uint8_t parcAtomicUint8_SubtractImpl(PARCAtomicUint8 *value, uint8_t subtrahend); + +bool parcAtomicUint8_CompareAndSwapImpl(PARCAtomicUint8 *value, uint8_t predicate, uint8_t newValue); + +#ifdef PARCLibrary_DISABLE_ATOMICS + +#define parcAtomicUint8_Add parcAtomicUint8_AddImpl + +#define parcAtomicUint8_Subtract parcAtomicUint8_SubtractImpl + +#define parcAtomicUint8_CompareAndSwap parcAtomicUint8_CompareAndSwapImpl + +#else + +#define parcAtomicUint8_Add(_atomic_uint8_, _addend_) \ + __sync_add_and_fetch(_atomic_uint8_, _addend_) + +#define parcAtomicUint8_Subtract(_atomic_uint8_, _subtrahend_) \ + __sync_sub_and_fetch(_atomic_uint8_, _subtrahend_) + +#define parcAtomicUint8_CompareAndSwap(_atomic_uint8_, _predicate_, _newValue_) \ + __sync_bool_compare_and_swap(_atomic_uint8_, _predicate_, _newValue_) +#endif + +#define parcAtomicUint8_Increment(_atomic_uint8_) parcAtomicUint8_Add(_atomic_uint8_, 1) +#define parcAtomicUint8_Decrement(_atomic_uint8_) parcAtomicUint8_Subtract(_atomic_uint8_, 1) + +/** + * Increase the number of references to a `PARCAtomicUint8` instance. + * + * Note that new `PARCAtomicUint8` is not created, + * only that the given `PARCAtomicUint8` reference count is incremented. + * Discard the reference by invoking `parcAtomicUint8_Release`. + * + * @param [in] instance A pointer to a valid PARCAtomicUint8 instance. + * + * @return The same value as @p instance. + * + * Example: + * @code + * { + * PARCAtomicUint8 *a = parcAtomicUint8_Create(); + * + * PARCAtomicUint8 *b = parcAtomicUint8_Acquire(); + * + * parcAtomicUint8_Release(&a); + * parcAtomicUint8_Release(&b); + * } + * @endcode + */ +PARCAtomicUint8 *parcAtomicUint8_Acquire(const PARCAtomicUint8 *instance); + +#ifdef PARCLibrary_DISABLE_VALIDATION +# define parcAtomicUint8_OptionalAssertValid(_instance_) +#else +# define parcAtomicUint8_OptionalAssertValid(_instance_) parcAtomicUint8_AssertValid(_instance_) +#endif + +/** + * Assert that the given `PARCAtomicUint8` instance is valid. + * + * @param [in] instance A pointer to a valid PARCAtomicUint8 instance. + * + * Example: + * @code + * { + * PARCAtomicUint8 *a = parcAtomicUint8_Create(); + * + * parcAtomicUint8_AssertValid(a); + * + * printf("Instance is valid.\n"); + * + * parcAtomicUint8_Release(&b); + * } + * @endcode + */ +void parcAtomicUint8_AssertValid(const PARCAtomicUint8 *instance); + +/** + * Create an instance of PARCAtomicUint8 + * + * <#Paragraphs Of Explanation#> + * + * @return non-NULL A pointer to a valid PARCAtomicUint8 instance. + * @return NULL An error occurred. + * + * Example: + * @code + * { + * PARCAtomicUint8 *a = parcAtomicUint8_Create(); + * + * parcAtomicUint8_Release(&b); + * } + * @endcode + */ +PARCAtomicUint8 *parcAtomicUint8_Create(uint8_t); + +/** + * Compares @p instance with @p other for order. + * + * Returns a negative integer, zero, or a positive integer as @p instance + * is less than, equal to, or greater than @p other. + * + * @param [in] instance A pointer to a valid PARCAtomicUint8 instance. + * @param [in] other A pointer to a valid PARCAtomicUint8 instance. + * + * @return <0 Instance is less than @p other. + * @return 0 Instance a and instance b compare the same. + * @return >0 Instance a is greater than instance b. + * + * Example: + * @code + * { + * PARCAtomicUint8 *a = parcAtomicUint8_Create(); + * PARCAtomicUint8 *b = parcAtomicUint8_Create(); + * + * if (parcAtomicUint8_Compare(a, b) == 0) { + * printf("Instances are equal.\n"); + * } + * + * parcAtomicUint8_Release(&a); + * parcAtomicUint8_Release(&b); + * } + * @endcode + * + * @see parcAtomicUint8_Equals + */ +int parcAtomicUint8_Compare(const PARCAtomicUint8 *instance, const PARCAtomicUint8 *other); + +/** + * Create an independent copy the given `PARCBuffer` + * + * A new buffer is created as a complete copy of the original. + * + * @param [in] original A pointer to a valid PARCAtomicUint8 instance. + * + * @return NULL Memory could not be allocated. + * @return non-NULL A pointer to a new `PARCAtomicUint8` instance. + * + * Example: + * @code + * { + * PARCAtomicUint8 *a = parcAtomicUint8_Create(); + * + * PARCAtomicUint8 *copy = parcAtomicUint8_Copy(&b); + * + * parcAtomicUint8_Release(&b); + * parcAtomicUint8_Release(©); + * } + * @endcode + */ +PARCAtomicUint8 *parcAtomicUint8_Copy(const PARCAtomicUint8 *original); + +/** + * Determine if two `PARCAtomicUint8` instances are equal. + * + * The following equivalence relations on non-null `PARCAtomicUint8` instances are maintained: * + * * It is reflexive: for any non-null reference value x, `parcAtomicUint8_Equals(x, x)` must return true. + * + * * It is symmetric: for any non-null reference values x and y, `parcAtomicUint8_Equals(x, y)` must return true if and only if + * `parcAtomicUint8_Equals(y x)` returns true. + * + * * It is transitive: for any non-null reference values x, y, and z, if + * `parcAtomicUint8_Equals(x, y)` returns true and + * `parcAtomicUint8_Equals(y, z)` returns true, + * then `parcAtomicUint8_Equals(x, z)` must return true. + * + * * It is consistent: for any non-null reference values x and y, multiple invocations of `parcAtomicUint8_Equals(x, y)` + * consistently return true or consistently return false. + * + * * For any non-null reference value x, `parcAtomicUint8_Equals(x, NULL)` must return false. + * + * @param [in] x A pointer to a valid PARCAtomicUint8 instance. + * @param [in] y A pointer to a valid PARCAtomicUint8 instance. + * + * @return true The instances x and y are equal. + * + * Example: + * @code + * { + * PARCAtomicUint8 *a = parcAtomicUint8_Create(); + * PARCAtomicUint8 *b = parcAtomicUint8_Create(); + * + * if (parcAtomicUint8_Equals(a, b)) { + * printf("Instances are equal.\n"); + * } + * + * parcAtomicUint8_Release(&a); + * parcAtomicUint8_Release(&b); + * } + * @endcode + * @see parcAtomicUint8_HashCode + */ +bool parcAtomicUint8_Equals(const PARCAtomicUint8 *x, const PARCAtomicUint8 *y); + +/** + * Returns a hash code value for the given instance. + * + * The general contract of `HashCode` is: + * + * Whenever it is invoked on the same instance more than once during an execution of an application, + * the `HashCode` function must consistently return the same value, + * provided no information used in a corresponding comparisons on the instance is modified. + * + * This value need not remain consistent from one execution of an application to another execution of the same application. + * If two instances are equal according to the {@link parcAtomicUint8_Equals} method, + * then calling the {@link parcAtomicUint8_HashCode} method on each of the two instances must produce the same integer result. + * + * It is not required that if two instances are unequal according to the + * {@link parcAtomicUint8_Equals} function, + * then calling the `parcAtomicUint8_HashCode` + * method on each of the two objects must produce distinct integer results. + * + * @param [in] instance A pointer to a valid PARCAtomicUint8 instance. + * + * @return The hashcode for the given instance. + * + * Example: + * @code + * { + * PARCAtomicUint8 *a = parcAtomicUint8_Create(); + * + * PARCHashCode hashValue = parcAtomicUint8_HashCode(buffer); + * parcAtomicUint8_Release(&a); + * } + * @endcode + */ +PARCHashCode parcAtomicUint8_HashCode(const PARCAtomicUint8 *instance); + +/** + * Determine if an instance of `PARCAtomicUint8` is valid. + * + * Valid means the internal state of the type is consistent with its required current or future behaviour. + * This may include the validation of internal instances of types. + * + * @param [in] instance A pointer to a valid PARCAtomicUint8 instance. + * + * @return true The instance is valid. + * @return false The instance is not valid. + * + * Example: + * @code + * { + * PARCAtomicUint8 *a = parcAtomicUint8_Create(); + * + * if (parcAtomicUint8_IsValid(a)) { + * printf("Instance is valid.\n"); + * } + * + * parcAtomicUint8_Release(&b); + * } + * @endcode + */ +bool parcAtomicUint8_IsValid(const PARCAtomicUint8 *instance); + +/** + * Release a previously acquired reference to the given `PARCAtomicUint8` instance, + * decrementing the reference count for the instance. + * + * The pointer to the instance is set to NULL as a side-effect of this function. + * + * If the invocation causes the last reference to the instance to be released, + * the instance is deallocated and the instance's implementation will perform + * additional cleanup and release other privately held references. + * + * @param [in,out] instancePtr A pointer to a pointer to the instance to release. + * + * Example: + * @code + * { + * PARCAtomicUint8 *a = parcAtomicUint8_Create(); + * + * parcAtomicUint8_Release(&a); + * } + * @endcode + */ +void parcAtomicUint8_Release(PARCAtomicUint8 **instancePtr); + +/** + * Get the current value of the given `PARCAtomicUint8` instance. + * + * @param [in] instance A pointer to a valid `PARCAtomicUint8` instance. + * + * @return the current value of the given `PARCAtomicUint8` instance. + * + * Example: + * @code + * { + * PARCAtomicUint8 *instance = parcAtomicUint8_Create(7); + * + * uint8_t value = parcAtomicUint8_GetValue(instance); + * + * parcAtomicUint8_Release(&instance); + * } + * @endcode + */ +uint8_t parcAtomicUint8_GetValue(const PARCAtomicUint8 *instance); +#endif |