/* | |
* FreeRTOS Kernel V10.0.0 | |
* Copyright (C) 2017 Amazon.com, Inc. or its affiliates. All Rights Reserved. | |
* | |
* Permission is hereby granted, free of charge, to any person obtaining a copy of | |
* this software and associated documentation files (the "Software"), to deal in | |
* the Software without restriction, including without limitation the rights to | |
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of | |
* the Software, and to permit persons to whom the Software is furnished to do so, | |
* subject to the following conditions: | |
* | |
* The above copyright notice and this permission notice shall be included in all | |
* copies or substantial portions of the Software. If you wish to use our Amazon | |
* FreeRTOS name, please do so in a fair use way that does not cause confusion. | |
* | |
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS | |
* FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR | |
* COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER | |
* IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN | |
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. | |
* | |
* http://www.FreeRTOS.org | |
* http://aws.amazon.com/freertos | |
* | |
* 1 tab == 4 spaces! | |
*/ | |
/** | |
* Manages a queue of strings that are waiting to be displayed. This is used to | |
* ensure mutual exclusion of console output. | |
* | |
* A task wishing to display a message will call vPrintDisplayMessage (), with a | |
* pointer to the string as the parameter. The pointer is posted onto the | |
* xPrintQueue queue. | |
* | |
* The task spawned in main. c blocks on xPrintQueue. When a message becomes | |
* available it calls pcPrintGetNextMessage () to obtain a pointer to the next | |
* string, then uses the functions defined in the portable layer FileIO. c to | |
* display the message. | |
* | |
* <b>NOTE:</b> | |
* Using console IO can disrupt real time performance - depending on the port. | |
* Standard C IO routines are not designed for real time applications. While | |
* standard IO is useful for demonstration and debugging an alternative method | |
* should be used if you actually require console IO as part of your application. | |
* | |
* \page PrintC print.c | |
* \ingroup DemoFiles | |
* <HR> | |
*/ | |
/* | |
Changes from V2.0.0 | |
+ Delay periods are now specified using variables and constants of | |
TickType_t rather than unsigned long. | |
*/ | |
#include <stdlib.h> | |
/* Scheduler include files. */ | |
#include "FreeRTOS.h" | |
#include "queue.h" | |
/* Demo program include files. */ | |
#include "print.h" | |
static QueueHandle_t xPrintQueue; | |
/*-----------------------------------------------------------*/ | |
void vPrintInitialise( void ) | |
{ | |
const unsigned portBASE_TYPE uxQueueSize = 20; | |
/* Create the queue on which errors will be reported. */ | |
xPrintQueue = xQueueCreate( uxQueueSize, ( unsigned portBASE_TYPE ) sizeof( char * ) ); | |
} | |
/*-----------------------------------------------------------*/ | |
void vPrintDisplayMessage( const char * const * ppcMessageToSend ) | |
{ | |
#ifdef USE_STDIO | |
xQueueSend( xPrintQueue, ( void * ) ppcMessageToSend, ( TickType_t ) 0 ); | |
#else | |
/* Stop warnings. */ | |
( void ) ppcMessageToSend; | |
#endif | |
} | |
/*-----------------------------------------------------------*/ | |
const char *pcPrintGetNextMessage( TickType_t xPrintRate ) | |
{ | |
char *pcMessage; | |
if( xQueueReceive( xPrintQueue, &pcMessage, xPrintRate ) == pdPASS ) | |
{ | |
return pcMessage; | |
} | |
else | |
{ | |
return NULL; | |
} | |
} | |