Source/include/StackMacros.h

/*
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	***************************************************************************
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*/

#ifndef STACK_MACROS_H
#define STACK_MACROS_H

/*
 * Call the stack overflow hook function if the stack of the task being swapped
 * out is currently overflowed, or looks like it might have overflowed in the
 * past.
 *
 * Setting configCHECK_FOR_STACK_OVERFLOW to 1 will cause the macro to check
 * the current stack state only - comparing the current top of stack value to
 * the stack limit.  Setting configCHECK_FOR_STACK_OVERFLOW to greater than 1
 * will also cause the last few stack bytes to be checked to ensure the value
 * to which the bytes were set when the task was created have not been 
 * overwritten.  Note this second test does not guarantee that an overflowed
 * stack will always be recognised.
 */

/*-----------------------------------------------------------*/

#if( configCHECK_FOR_STACK_OVERFLOW == 0 )

	/* FreeRTOSConfig.h is not set to check for stack overflows. */
	#define taskFIRST_CHECK_FOR_STACK_OVERFLOW()
	#define taskSECOND_CHECK_FOR_STACK_OVERFLOW()

#endif /* configCHECK_FOR_STACK_OVERFLOW == 0 */
/*-----------------------------------------------------------*/

#if( configCHECK_FOR_STACK_OVERFLOW == 1 )

	/* FreeRTOSConfig.h is only set to use the first method of
	overflow checking. */
	#define taskSECOND_CHECK_FOR_STACK_OVERFLOW()

#endif
/*-----------------------------------------------------------*/

#if( ( configCHECK_FOR_STACK_OVERFLOW > 0 ) && ( portSTACK_GROWTH < 0 ) )

	/* Only the current stack state is to be checked. */
	#define taskFIRST_CHECK_FOR_STACK_OVERFLOW()														\
	{																									\
	extern void vApplicationStackOverflowHook( xTaskHandle *pxTask, signed portCHAR *pcTaskName );		\
																										\
		/* Is the currently saved stack pointer within the stack limit? */								\
		if( pxCurrentTCB->pxTopOfStack <= pxCurrentTCB->pxStack )										\
		{																								\
			vApplicationStackOverflowHook( ( xTaskHandle ) pxCurrentTCB, pxCurrentTCB->pcTaskName );	\
		}																								\
	}

#endif /* configCHECK_FOR_STACK_OVERFLOW == 1 */
/*-----------------------------------------------------------*/

#if( ( configCHECK_FOR_STACK_OVERFLOW > 0 ) && ( portSTACK_GROWTH > 0 ) )

	/* Only the current stack state is to be checked. */
	#define taskFIRST_CHECK_FOR_STACK_OVERFLOW()														\
	{																									\
	extern void vApplicationStackOverflowHook( xTaskHandle *pxTask, signed portCHAR *pcTaskName );		\
																										\
		/* Is the currently saved stack pointer within the stack limit? */								\
		if( pxCurrentTCB->pxTopOfStack >= pxCurrentTCB->pxEndOfStack )									\
		{																								\
			vApplicationStackOverflowHook( ( xTaskHandle ) pxCurrentTCB, pxCurrentTCB->pcTaskName );	\
		}																								\
	}

#endif /* configCHECK_FOR_STACK_OVERFLOW == 1 */
/*-----------------------------------------------------------*/

#if( ( configCHECK_FOR_STACK_OVERFLOW > 1 ) && ( portSTACK_GROWTH < 0 ) )

	#define taskSECOND_CHECK_FOR_STACK_OVERFLOW()																									\
	{																																				\
	extern void vApplicationStackOverflowHook( xTaskHandle *pxTask, signed portCHAR *pcTaskName );													\
	static const unsigned portCHAR ucExpectedStackBytes[] = {	tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE,		\
																tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE,		\
																tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE,		\
																tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE,		\
																tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE };	\
																																					\
																																					\
		/* Has the extremity of the task stack ever been written over? */																			\
		if( memcmp( ( void * ) pxCurrentTCB->pxStack, ( void * ) ucExpectedStackBytes, sizeof( ucExpectedStackBytes ) ) != 0 )						\
		{																																			\
			vApplicationStackOverflowHook( ( xTaskHandle ) pxCurrentTCB, pxCurrentTCB->pcTaskName );												\
		}																																			\
	}

#endif /* #if( configCHECK_FOR_STACK_OVERFLOW > 1 ) */
/*-----------------------------------------------------------*/

#if( ( configCHECK_FOR_STACK_OVERFLOW > 1 ) && ( portSTACK_GROWTH > 0 ) )

	#define taskSECOND_CHECK_FOR_STACK_OVERFLOW()																									\
	{																																				\
	extern void vApplicationStackOverflowHook( xTaskHandle *pxTask, signed portCHAR *pcTaskName );													\
	portCHAR *pcEndOfStack = ( portCHAR * ) pxCurrentTCB->pxEndOfStack;																				\
	static const unsigned portCHAR ucExpectedStackBytes[] = {	tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE,		\
																tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE,		\
																tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE,		\
																tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE,		\
																tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE, tskSTACK_FILL_BYTE };	\
																																					\
																																					\
		pcEndOfStack -= sizeof( ucExpectedStackBytes );																								\
																																					\
		/* Has the extremity of the task stack ever been written over? */																			\
		if( memcmp( ( void * ) pcEndOfStack, ( void * ) ucExpectedStackBytes, sizeof( ucExpectedStackBytes ) ) != 0 )								\
		{																																			\
			vApplicationStackOverflowHook( ( xTaskHandle ) pxCurrentTCB, pxCurrentTCB->pcTaskName );												\
		}																																			\
	}

#endif /* #if( configCHECK_FOR_STACK_OVERFLOW > 1 ) */
/*-----------------------------------------------------------*/

#endif /* STACK_MACROS_H */