Suppress MISRA C:2012 rule 21.6 for snprintf (#877)

Suppress MISRA C:2012 rule 21.6 for snprintf

Author: chinglee-iot

MISRA.md

@@ -107,6 +107,15 @@ _Ref 11.5.5_
  because data storage buffers are implemented as uint8_t arrays for the
  ease of sizing, alignment and access.
 
+#### Rule 21.6
+
+MISRA C-2012 Rule 21.6: The Standard Library input/output functions shall not
+be used.
+
+_Ref 21.6.1_
+ - The Standard Library function snprintf is used in vTaskListTasks and
+ vTaskGetRunTimeStatistics APIs, both of which are utility functions only and
+ are not considered part of core kernel implementation.
 
 ### MISRA configuration
 

tasks.c

@@ -7348,22 +7348,28 @@ static void prvResetNextTaskUnblockTime( void )
  {
  /* Write the rest of the string. */
  #if ( ( configUSE_CORE_AFFINITY == 1 ) && ( configNUMBER_OF_CORES > 1 ) )
+ /* MISRA Ref 21.6.1 [snprintf for utility] */
+ /* More details at: https://github.com/FreeRTOS/FreeRTOS-Kernel/blob/main/MISRA.md#rule-216 */
+ /* coverity[misra_c_2012_rule_21_6_violation] */
  iSnprintfReturnValue = snprintf( pcWriteBuffer,
  uxBufferLength - uxConsumedBufferLength,
  "\t%c\t%u\t%u\t%u\t0x%x\r\n",
  cStatus,
  ( unsigned int ) pxTaskStatusArray[ x ].uxCurrentPriority,
  ( unsigned int ) pxTaskStatusArray[ x ].usStackHighWaterMark,
  ( unsigned int ) pxTaskStatusArray[ x ].xTaskNumber,
- ( unsigned int ) pxTaskStatusArray[ x ].uxCoreAffinityMask ); /*lint !e586 sprintf() allowed as this is compiled with many compilers and this is a utility function only - not part of the core kernel implementation. */
+ ( unsigned int ) pxTaskStatusArray[ x ].uxCoreAffinityMask );
  #else /* ( ( configUSE_CORE_AFFINITY == 1 ) && ( configNUMBER_OF_CORES > 1 ) ) */
+ /* MISRA Ref 21.6.1 [snprintf for utility] */
+ /* More details at: https://github.com/FreeRTOS/FreeRTOS-Kernel/blob/main/MISRA.md#rule-216 */
+ /* coverity[misra_c_2012_rule_21_6_violation] */
  iSnprintfReturnValue = snprintf( pcWriteBuffer,
  uxBufferLength - uxConsumedBufferLength,
  "\t%c\t%u\t%u\t%u\r\n",
  cStatus,
  ( unsigned int ) pxTaskStatusArray[ x ].uxCurrentPriority,
  ( unsigned int ) pxTaskStatusArray[ x ].usStackHighWaterMark,
- ( unsigned int ) pxTaskStatusArray[ x ].xTaskNumber ); /*lint !e586 sprintf() allowed as this is compiled with many compilers and this is a utility function only - not part of the core kernel implementation. */
+ ( unsigned int ) pxTaskStatusArray[ x ].xTaskNumber );
  #endif /* ( ( configUSE_CORE_AFFINITY == 1 ) && ( configNUMBER_OF_CORES > 1 ) ) */
  uxCharsWrittenBySnprintf = prvSnprintfReturnValueToCharsWritten( iSnprintfReturnValue, uxBufferLength - uxConsumedBufferLength );
 
@@ -7496,21 +7502,27 @@ static void prvResetNextTaskUnblockTime( void )
  {
  #ifdef portLU_PRINTF_SPECIFIER_REQUIRED
  {
+ /* MISRA Ref 21.6.1 [snprintf for utility] */
+ /* More details at: https://github.com/FreeRTOS/FreeRTOS-Kernel/blob/main/MISRA.md#rule-216 */
+ /* coverity[misra_c_2012_rule_21_6_violation] */
  iSnprintfReturnValue = snprintf( pcWriteBuffer,
  uxBufferLength - uxConsumedBufferLength,
  "\t%lu\t\t%lu%%\r\n",
  pxTaskStatusArray[ x ].ulRunTimeCounter,
  ulStatsAsPercentage );
  }
- #else
+ #else /* ifdef portLU_PRINTF_SPECIFIER_REQUIRED */
  {
  /* sizeof( int ) == sizeof( long ) so a smaller
  * printf() library can be used. */
+ /* MISRA Ref 21.6.1 [snprintf for utility] */
+ /* More details at: https://github.com/FreeRTOS/FreeRTOS-Kernel/blob/main/MISRA.md#rule-216 */
+ /* coverity[misra_c_2012_rule_21_6_violation] */
  iSnprintfReturnValue = snprintf( pcWriteBuffer,
  uxBufferLength - uxConsumedBufferLength,
  "\t%u\t\t%u%%\r\n",
  ( unsigned int ) pxTaskStatusArray[ x ].ulRunTimeCounter,
- ( unsigned int ) ulStatsAsPercentage ); /*lint !e586 sprintf() allowed as this is compiled with many compilers and this is a utility function only - not part of the core kernel implementation. */
+ ( unsigned int ) ulStatsAsPercentage );
  }
  #endif /* ifdef portLU_PRINTF_SPECIFIER_REQUIRED */
  }
@@ -7520,6 +7532,9 @@ static void prvResetNextTaskUnblockTime( void )
  * consumed less than 1% of the total run time. */
  #ifdef portLU_PRINTF_SPECIFIER_REQUIRED
  {
+ /* MISRA Ref 21.6.1 [snprintf for utility] */
+ /* More details at: https://github.com/FreeRTOS/FreeRTOS-Kernel/blob/main/MISRA.md#rule-216 */
+ /* coverity[misra_c_2012_rule_21_6_violation] */
  iSnprintfReturnValue = snprintf( pcWriteBuffer,
  uxBufferLength - uxConsumedBufferLength,
  "\t%lu\t\t<1%%\r\n",
@@ -7529,10 +7544,13 @@ static void prvResetNextTaskUnblockTime( void )
  {
  /* sizeof( int ) == sizeof( long ) so a smaller
  * printf() library can be used. */
+ /* MISRA Ref 21.6.1 [snprintf for utility] */
+ /* More details at: https://github.com/FreeRTOS/FreeRTOS-Kernel/blob/main/MISRA.md#rule-216 */
+ /* coverity[misra_c_2012_rule_21_6_violation] */
  iSnprintfReturnValue = snprintf( pcWriteBuffer,
  uxBufferLength - uxConsumedBufferLength,
  "\t%u\t\t<1%%\r\n",
- ( unsigned int ) pxTaskStatusArray[ x ].ulRunTimeCounter ); /*lint !e586 sprintf() allowed as this is compiled with many compilers and this is a utility function only - not part of the core kernel implementation. */
+ ( unsigned int ) pxTaskStatusArray[ x ].ulRunTimeCounter );
  }
  #endif /* ifdef portLU_PRINTF_SPECIFIER_REQUIRED */
  }