Context Manager

Detailed Description

The SeCtx library makes it possible to use sequential functions in an event driven system such as a bare metal (non RTOS) system.

It does so by implementing a method for saving and restoring the stack by using the standard C library functions setjmp/longjmp.

See Bare Metal Systems for an introduction.

Collaboration diagram for Context Manager:

Classes
struct	SeCtx
	SeCtx structure: See Context Manager and Bare Metal Systems for details. More...

Macros
#define	SeCtx_destructor(o)
	No operation for a context using a caller-supplied static stack buffer. More...

Typedefs
typedef void(*	SeCtxTask) (struct SeCtx *ctx)
	The task/thread entry point. More...
typedef struct SeCtx	SeCtx
	SeCtx structure: See Context Manager and Bare Metal Systems for details. More...

Functions
void	SeCtx_constructor (SeCtx *o, SeCtxTask t, void *buf, int bufLen)
	Create a Context Manager instance. More...
void	SeCtx_panic (SeCtx *o, U32 size)
	Function you must implement. More...

Macro Definition Documentation

SeCtx_destructor

#define SeCtx_destructor

(

o

)

No operation for a context using a caller-supplied static stack buffer.

Parameters

o	SeCtx *; initialized context. Retire it from the scheduler before releasing its caller-owned storage. With DYNAMIC_SE_CTX, this name is a function that releases the dynamically allocated stack buffer.

Typedef Documentation

SeCtx

typedef struct SeCtx SeCtx

SeCtx structure: See Context Manager and Bare Metal Systems for details.

SeCtxTask

typedef void(* SeCtxTask) (struct SeCtx *ctx)

The task/thread entry point.

Function Documentation

SeCtx_constructor()

void SeCtx_constructor	(	SeCtx *	o,
		SeCtxTask	t,
		void *	buf,
		int	bufLen
	)

Create a Context Manager instance.

Parameters

o	uninitialized data of size sizeof(SeCtx).
t	the task/thread to call
buf	buffer used for storing the stack when switching from sequential mode to event driven mode.
bufLen	buffer length.

See also

SeCtx_panic

SeCtx_panic()

void SeCtx_panic	(	SeCtx *	o,
		U32	size
	)

Function you must implement.

This function is called if the buffer provided in SeCtx_constructor is too small.

Parameters

o	Context whose stack buffer could not be allocated or is too small; NULL for a dynamic stack request exceeding 40 KiB.
size	Required stack-save size in bytes.