Stack Utility Functions

Classes
struct	_OSRTStack

Macros
#define	rtxStackIsEmpty(stack)   (OSBOOL)((stack).dlist.count == 0)

Typedefs
typedef struct _OSRTStack	OSRTStack

Functions
OSRTStack *	rtxStackCreate (struct OSCTXT *pctxt)
void	rtxStackInit (struct OSCTXT *pctxt, OSRTStack *pStack)
void *	rtxStackPop (OSRTStack *pStack)
int	rtxStackPush (OSRTStack *pStack, void *pData)
void *	rtxStackPeek (OSRTStack *pStack)

Detailed Description

This is a simple stack structure with supporting push and pop functions. Different initialization routines are provided to permit different memory management schemes.

Macro Definition Documentation

rtxStackIsEmpty

#define rtxStackIsEmpty

(

stack

)

(OSBOOL)((stack).dlist.count == 0)

This macro tests if the stack is empty.

Parameters

stack

Stack structure variable to be tested.

Function Documentation

rtxStackCreate()

OSRTStack* rtxStackCreate

(

struct OSCTXT *

pctxt

)

This function creates a new stack structure. It allocates memory for the structure and calls rtxStackInit to initialize the structure.

Parameters

pctxt

A pointer to the context with which the stack is associated.

Returns

A pointer to an allocated stack structure.

rtxStackInit()

void rtxStackInit	(	struct OSCTXT *	pctxt,
		OSRTStack *	pStack
	)

This function initializes a stack structure. It sets the number of elements to zero and sets all internal pointer values to NULL.

Parameters

pctxt	A pointer to the context with which the stack is associated.
pStack	A pointer to a stack structure to be initialized.

rtxStackPeek()

void* rtxStackPeek

(

OSRTStack *

pStack

)

This functions returns the data item on the top of the stack.

Parameters

pStack

A pointer to the structure onto which the data item is to be pushed. The pointer updated to the stack structure

Returns

Pointer to data item at top of stack or NULL if stack empty.

• 0 (0) = success,
• negative return value is error.

rtxStackPop()

void* rtxStackPop

(

OSRTStack *

pStack

)

This function pops an item off the stack.

Parameters

pStack

The pointer to the stack structure from which the value is to be popped. Pointer to the updated stack structure.

Returns

The pointer to the item popped from the stack

rtxStackPush()

int rtxStackPush	(	OSRTStack *	pStack,
		void *	pData
	)

This function pushes an item onto the stack.

Parameters

pStack	A pointer to the structure onto which the data item is to be pushed. The pointer updated to the stack structure
pData	A pointer to the data item to be pushed on the stack.

Returns

Completion status of operation:

• 0 (0) = success,
• negative return value is error.