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/**************************************************************************/
/* */
/* Copyright (c) Microsoft Corporation. All rights reserved. */
/* */
/* This software is licensed under the Microsoft Software License */
/* Terms for Microsoft Azure RTOS. Full text of the license can be */
/* found in the LICENSE file at https://aka.ms/AzureRTOS_EULA */
/* and in the root directory of this software. */
/* */
/**************************************************************************/
/**************************************************************************/
/**************************************************************************/
/** */
/** ThreadX Component */
/** */
/** Semaphore */
/** */
/**************************************************************************/
/**************************************************************************/
#define TX_SOURCE_CODE
/* Include necessary system files. */
#include "tx_api.h"
#include "tx_trace.h"
#include "tx_semaphore.h"
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* _tx_semaphore_create PORTABLE C */
/* 6.1 */
/* AUTHOR */
/* */
/* William E. Lamie, Microsoft Corporation */
/* */
/* DESCRIPTION */
/* */
/* This function creates a counting semaphore with the initial count */
/* specified in this call. */
/* */
/* INPUT */
/* */
/* semaphore_ptr Pointer to semaphore control block*/
/* name_ptr Pointer to semaphore name */
/* initial_count Initial semaphore count */
/* */
/* OUTPUT */
/* */
/* TX_SUCCESS Successful completion status */
/* */
/* CALLS */
/* */
/* None */
/* */
/* CALLED BY */
/* */
/* Application Code */
/* */
/* RELEASE HISTORY */
/* */
/* DATE NAME DESCRIPTION */
/* */
/* 05-19-2020 William E. Lamie Initial Version 6.0 */
/* 09-30-2020 Yuxin Zhou Modified comment(s), */
/* resulting in version 6.1 */
/* */
/**************************************************************************/
UINT _tx_semaphore_create(TX_SEMAPHORE *semaphore_ptr, CHAR *name_ptr, ULONG initial_count)
{
TX_INTERRUPT_SAVE_AREA
TX_SEMAPHORE *next_semaphore;
TX_SEMAPHORE *previous_semaphore;
/* Initialize semaphore control block to all zeros. */
TX_MEMSET(semaphore_ptr, 0, (sizeof(TX_SEMAPHORE)));
/* Setup the basic semaphore fields. */
semaphore_ptr -> tx_semaphore_name = name_ptr;
semaphore_ptr -> tx_semaphore_count = initial_count;
/* Disable interrupts to place the semaphore on the created list. */
TX_DISABLE
/* Setup the semaphore ID to make it valid. */
semaphore_ptr -> tx_semaphore_id = TX_SEMAPHORE_ID;
/* Place the semaphore on the list of created semaphores. First,
check for an empty list. */
if (_tx_semaphore_created_count == TX_EMPTY)
{
/* The created semaphore list is empty. Add semaphore to empty list. */
_tx_semaphore_created_ptr = semaphore_ptr;
semaphore_ptr -> tx_semaphore_created_next = semaphore_ptr;
semaphore_ptr -> tx_semaphore_created_previous = semaphore_ptr;
}
else
{
/* This list is not NULL, add to the end of the list. */
next_semaphore = _tx_semaphore_created_ptr;
previous_semaphore = next_semaphore -> tx_semaphore_created_previous;
/* Place the new semaphore in the list. */
next_semaphore -> tx_semaphore_created_previous = semaphore_ptr;
previous_semaphore -> tx_semaphore_created_next = semaphore_ptr;
/* Setup this semaphore's next and previous created links. */
semaphore_ptr -> tx_semaphore_created_previous = previous_semaphore;
semaphore_ptr -> tx_semaphore_created_next = next_semaphore;
}
/* Increment the created count. */
_tx_semaphore_created_count++;
/* Optional semaphore create extended processing. */
TX_SEMAPHORE_CREATE_EXTENSION(semaphore_ptr)
/* If trace is enabled, register this object. */
TX_TRACE_OBJECT_REGISTER(TX_TRACE_OBJECT_TYPE_SEMAPHORE, semaphore_ptr, name_ptr, initial_count, 0)
/* If trace is enabled, insert this event into the trace buffer. */
TX_TRACE_IN_LINE_INSERT(TX_TRACE_SEMAPHORE_CREATE, semaphore_ptr, initial_count, TX_POINTER_TO_ULONG_CONVERT(&next_semaphore), 0, TX_TRACE_SEMAPHORE_EVENTS)
/* Log this kernel call. */
TX_EL_SEMAPHORE_CREATE_INSERT
/* Restore interrupts. */
TX_RESTORE
/* Return TX_SUCCESS. */
return(TX_SUCCESS);
}
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