Initial commit: cframework. Longbow and Libparc

Change-Id: I90378dbd30da6033b20fb1f829b3b822cf366c59
Signed-off-by: Luca Muscariello <lumuscar+fdio@cisco.com>

1 files changed, 431 insertions, 0 deletions

diff --git a/libparc/parc/concurrent/parc_Timer.h b/libparc/parc/concurrent/parc_Timer.h
new file mode 100755
index 00000000..416bfba4
--- /dev/null
+++ b/libparc/parc/concurrent/parc_Timer.h
@@ -0,0 +1,431 @@
+/*
+ * 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_Timer.h
+ * @ingroup threading
+ * @brief A facility for threads to schedule tasks for future execution in a background thread.
+ *
+ * Tasks may be scheduled for one-time execution, or for repeated execution at regular intervals.
+ *
+ * Corresponding to each Timer object is a single background thread that is used to execute all of the timer's tasks,
+ * sequentially. Timer tasks should complete quickly.
+ * If a timer task takes excessive time to complete, it "hogs" the timer's task execution thread.
+ * This can, in turn, delay the execution of subsequent tasks,
+ * which may "bunch up" and execute in rapid succession when (and if) the offending task finally completes.
+ *
+ * After the last live reference to a Timer object goes away and all outstanding tasks have completed execution,
+ * the timer's task execution thread terminates gracefully (and becomes subject to garbage collection).
+ * However, this can take arbitrarily long to occur.
+ * By default, the task execution thread does not run as a daemon thread,
+ * so it is capable of keeping an application from terminating.
+ * If a caller wants to terminate a timer's task execution thread rapidly, the caller should invoke the timer's cancel method.
+ *
+ * If the timer's task execution thread terminates unexpectedly,
+ * for example, because its stop method is invoked,
+ * any further attempt to schedule a task on the timer will result in an IllegalStateException,
+ * as if the timer's cancel method had been invoked.
+ *
+ * This class is thread-safe: multiple threads can share a single Timer object without the need for external synchronization.
+ *
+ * This class does not offer real-time guarantees: it schedules tasks using the Object.wait(long) method.
+ *
+ */
+#ifndef PARCLibrary_parc_Timer
+#define PARCLibrary_parc_Timer
+#include <stdbool.h>
+
+#include <parc/algol/parc_JSON.h>
+#include <parc/algol/parc_HashCode.h>
+#include <parc/concurrent/parc_FutureTask.h>
+
+struct PARCTimer;
+typedef struct PARCTimer PARCTimer;
+
+/**
+ * Increase the number of references to a `PARCTimer` instance.
+ *
+ * Note that new `PARCTimer` is not created,
+ * only that the given `PARCTimer` reference count is incremented.
+ * Discard the reference by invoking `parcTimer_Release`.
+ *
+ * @param [in] instance A pointer to a valid PARCTimer instance.
+ *
+ * @return The same value as @p instance.
+ *
+ * Example:
+ * @code
+ * {
+ *     PARCTimer *a = parcTimer_Create();
+ *
+ *     PARCTimer *b = parcTimer_Acquire();
+ *
+ *     parcTimer_Release(&a);
+ *     parcTimer_Release(&b);
+ * }
+ * @endcode
+ */
+PARCTimer *parcTimer_Acquire(const PARCTimer *instance);
+
+#ifdef PARCLibrary_DISABLE_VALIDATION
+#  define parcTimer_OptionalAssertValid(_instance_)
+#else
+#  define parcTimer_OptionalAssertValid(_instance_) parcTimer_AssertValid(_instance_)
+#endif
+
+/**
+ * Assert that the given `PARCTimer` instance is valid.
+ *
+ * @param [in] instance A pointer to a valid PARCTimer instance.
+ *
+ * Example:
+ * @code
+ * {
+ *     PARCTimer *a = parcTimer_Create();
+ *
+ *     parcTimer_AssertValid(a);
+ *
+ *     printf("Instance is valid.\n");
+ *
+ *     parcTimer_Release(&b);
+ * }
+ * @endcode
+ */
+void parcTimer_AssertValid(const PARCTimer *instance);
+
+/**
+ * Create an instance of PARCTimer
+ *
+ * <#Paragraphs Of Explanation#>
+ *
+ * @return non-NULL A pointer to a valid PARCTimer instance.
+ * @return NULL An error occurred.
+ *
+ * Example:
+ * @code
+ * {
+ *     PARCTimer *a = parcTimer_Create();
+ *
+ *     parcTimer_Release(&a);
+ * }
+ * @endcode
+ */
+PARCTimer *parcTimer_Create(void);
+
+/**
+ * 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 PARCTimer instance.
+ * @param [in] other A pointer to a valid PARCTimer 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
+ * {
+ *     PARCTimer *a = parcTimer_Create();
+ *     PARCTimer *b = parcTimer_Create();
+ *
+ *     if (parcTimer_Compare(a, b) == 0) {
+ *         printf("Instances are equal.\n");
+ *     }
+ *
+ *     parcTimer_Release(&a);
+ *     parcTimer_Release(&b);
+ * }
+ * @endcode
+ *
+ * @see parcTimer_Equals
+ */
+int parcTimer_Compare(const PARCTimer *instance, const PARCTimer *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 PARCTimer instance.
+ *
+ * @return NULL Memory could not be allocated.
+ * @return non-NULL A pointer to a new `PARCTimer` instance.
+ *
+ * Example:
+ * @code
+ * {
+ *     PARCTimer *a = parcTimer_Create();
+ *
+ *     PARCTimer *copy = parcTimer_Copy(&b);
+ *
+ *     parcTimer_Release(&b);
+ *     parcTimer_Release(&copy);
+ * }
+ * @endcode
+ */
+PARCTimer *parcTimer_Copy(const PARCTimer *original);
+
+/**
+ * Print a human readable representation of the given `PARCTimer`.
+ *
+ * @param [in] instance A pointer to a valid PARCTimer instance.
+ * @param [in] indentation The indentation level to use for printing.
+ *
+ * Example:
+ * @code
+ * {
+ *     PARCTimer *a = parcTimer_Create();
+ *
+ *     parcTimer_Display(a, 0);
+ *
+ *     parcTimer_Release(&a);
+ * }
+ * @endcode
+ */
+void parcTimer_Display(const PARCTimer *instance, int indentation);
+
+/**
+ * Determine if two `PARCTimer` instances are equal.
+ *
+ * The following equivalence relations on non-null `PARCTimer` instances are maintained: *
+ *   * It is reflexive: for any non-null reference value x, `parcTimer_Equals(x, x)` must return true.
+ *
+ *   * It is symmetric: for any non-null reference values x and y, `parcTimer_Equals(x, y)` must return true if and only if
+ *        `parcTimer_Equals(y x)` returns true.
+ *
+ *   * It is transitive: for any non-null reference values x, y, and z, if
+ *        `parcTimer_Equals(x, y)` returns true and
+ *        `parcTimer_Equals(y, z)` returns true,
+ *        then `parcTimer_Equals(x, z)` must return true.
+ *
+ *   * It is consistent: for any non-null reference values x and y, multiple invocations of `parcTimer_Equals(x, y)`
+ *         consistently return true or consistently return false.
+ *
+ *   * For any non-null reference value x, `parcTimer_Equals(x, NULL)` must return false.
+ *
+ * @param [in] x A pointer to a valid PARCTimer instance.
+ * @param [in] y A pointer to a valid PARCTimer instance.
+ *
+ * @return true The instances x and y are equal.
+ *
+ * Example:
+ * @code
+ * {
+ *     PARCTimer *a = parcTimer_Create();
+ *     PARCTimer *b = parcTimer_Create();
+ *
+ *     if (parcTimer_Equals(a, b)) {
+ *         printf("Instances are equal.\n");
+ *     }
+ *
+ *     parcTimer_Release(&a);
+ *     parcTimer_Release(&b);
+ * }
+ * @endcode
+ * @see parcTimer_HashCode
+ */
+bool parcTimer_Equals(const PARCTimer *x, const PARCTimer *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 parcTimer_Equals} method,
+ * then calling the {@link parcTimer_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 parcTimer_Equals} function,
+ * then calling the `parcTimer_HashCode`
+ * method on each of the two objects must produce distinct integer results.
+ *
+ * @param [in] instance A pointer to a valid PARCTimer instance.
+ *
+ * @return The hashcode for the given instance.
+ *
+ * Example:
+ * @code
+ * {
+ *     PARCTimer *a = parcTimer_Create();
+ *
+ *     PARCHashCode hashValue = parcTimer_HashCode(buffer);
+ *     parcTimer_Release(&a);
+ * }
+ * @endcode
+ */
+PARCHashCode parcTimer_HashCode(const PARCTimer *instance);
+
+/**
+ * Determine if an instance of `PARCTimer` 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 PARCTimer instance.
+ *
+ * @return true The instance is valid.
+ * @return false The instance is not valid.
+ *
+ * Example:
+ * @code
+ * {
+ *     PARCTimer *a = parcTimer_Create();
+ *
+ *     if (parcTimer_IsValid(a)) {
+ *         printf("Instance is valid.\n");
+ *     }
+ *
+ *     parcTimer_Release(&a);
+ * }
+ * @endcode
+ *
+ */
+bool parcTimer_IsValid(const PARCTimer *instance);
+
+/**
+ * Release a previously acquired reference to the given `PARCTimer` 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
+ * {
+ *     PARCTimer *a = parcTimer_Create();
+ *
+ *     parcTimer_Release(&a);
+ * }
+ * @endcode
+ */
+void parcTimer_Release(PARCTimer **instancePtr);
+
+/**
+ * Create a `PARCJSON` instance (representation) of the given object.
+ *
+ * @param [in] instance A pointer to a valid PARCTimer instance.
+ *
+ * @return NULL Memory could not be allocated to contain the `PARCJSON` instance.
+ * @return non-NULL An allocated C string that must be deallocated via parcMemory_Deallocate().
+ *
+ * Example:
+ * @code
+ * {
+ *     PARCTimer *a = parcTimer_Create();
+ *
+ *     PARCJSON *json = parcTimer_ToJSON(a);
+ *
+ *     printf("JSON representation: %s\n", parcJSON_ToString(json));
+ *     parcJSON_Release(&json);
+ *
+ *     parcTimer_Release(&a);
+ * }
+ * @endcode
+ */
+PARCJSON *parcTimer_ToJSON(const PARCTimer *instance);
+
+/**
+ * Produce a null-terminated string representation of the specified `PARCTimer`.
+ *
+ * The result must be freed by the caller via {@link parcMemory_Deallocate}.
+ *
+ * @param [in] instance A pointer to a valid PARCTimer instance.
+ *
+ * @return NULL Cannot allocate memory.
+ * @return non-NULL A pointer to an allocated, null-terminated C string that must be deallocated via {@link parcMemory_Deallocate}.
+ *
+ * Example:
+ * @code
+ * {
+ *     PARCTimer *a = parcTimer_Create();
+ *
+ *     char *string = parcTimer_ToString(a);
+ *
+ *     parcTimer_Release(&a);
+ *
+ *     parcMemory_Deallocate(&string);
+ * }
+ * @endcode
+ *
+ * @see parcTimer_Display
+ */
+char *parcTimer_ToString(const PARCTimer *timer);
+
+/**
+ * Terminates this timer, discarding any currently scheduled tasks.
+ *
+ * Does not interfere with a currently executing task (if it exists).
+ * Once a timer has been terminated, its execution thread terminates gracefully,
+ * and no more tasks may be scheduled on it.
+ *
+ * Note that calling this method from within the run method of a timer task that was invoked
+ * by this timer absolutely guarantees that the ongoing task execution is the last task execution
+ * that will ever be performed by this timer.
+ *
+ * This method may be called repeatedly; the second and subsequent calls have no effect.
+ */
+void parcTimer_Cancel(PARCTimer *timer);
+
+/**
+ * Removes all cancelled tasks from this timer's task queue.
+ *
+ * Calling this method has no effect on the behavior of the timer,
+ * but eliminates the references to the cancelled tasks from the queue.
+ * If there are no external references to these tasks, they become eligible for garbage collection.
+ *
+ * Most programs will have no need to call this method.
+ * It is designed for use by the rare application that cancels a large number of tasks.
+ * Calling this method trades time for space: the runtime of the method may be proportional to
+ * n + c log n, where n is the number of tasks in the queue and c is the number of cancelled tasks.
+ *
+ * It is permissible to call this method from within a task scheduled on this timer.
+ *
+ * @returns the number of tasks removed from the queue.
+ */
+int parcTimer_Purge(PARCTimer *timer);
+
+/**
+ * Schedules the specified task for execution at the specified time.
+ */
+void parcTimer_ScheduleAtTime(PARCTimer *timer, PARCFutureTask *task, time_t absoluteTime);
+
+/**
+ * Schedules the specified task for repeated fixed-delay execution, beginning at the specified time.
+ */
+void parcTimer_ScheduleAtTimeAndRepeat(PARCTimer *timer, PARCFutureTask *task, time_t firstTime, long period);
+
+/**
+ * Schedules the specified task for execution after the specified delay.
+ */
+void parcTimer_ScheduleAfterDelay(PARCTimer *timer, PARCFutureTask *task, long delay);
+
+/**
+ * Schedules the specified task for repeated fixed-delay execution, beginning after the specified delay.
+ */
+void parcTimer_ScheduleAfterDelayAndRepeat(PARCTimer *timer, PARCFutureTask *task, long delay, long period);
+#endif