qep_msm.c File Reference

QMsm implementation More...

#include "qep_port.h"
#include "qassert.h"
#include "qs_port.h"
#include "qs_pkg.h"

Include dependency graph for qep_msm.c:

Go to the source code of this file.

Macros
#define	QEP_ACT_PTR_INC_(act_)   (++(act_))
	Internal QEP macro to increment the given action table act_. More...

Enumerations
enum	{ QMSM_MAX_ENTRY_DEPTH_ = 4 }
	internal QEP constants More...

Functions
void	QMsm_ctor (QMsm *const me, QStateHandler initial)
bool	QMsm_isInState (QMsm const *const me, QMState const *const state)
QMState const *	QMsm_childStateObj_ (QMsm const *const me, QMState const *const parent)

Variables
static struct QMState const	l_msm_top_s

Detailed Description

QMsm implementation

Definition in file qep_msm.c.

Macro Definition Documentation

QEP_ACT_PTR_INC_

#define QEP_ACT_PTR_INC_

(

act_

)

(++(act_))

Internal QEP macro to increment the given action table act_.

Note

Incrementing a pointer violates the MISRA-C 2004 Rule 17.4(req), pointer arithmetic other than array indexing. Encapsulating this violation in a macro allows to selectively suppress this specific deviation.

Definition at line 75 of file qep_msm.c.

Enumeration Type Documentation

anonymous enum

anonymous enum

internal QEP constants

Enumerator
QMSM_MAX_ENTRY_DEPTH_	maximum depth of entry levels in a MSM for transition to history.

Definition at line 54 of file qep_msm.c.

Function Documentation

QMsm_ctor()

void QMsm_ctor	(	QMsm *const	me,
		QStateHandler	initial
	)

Description

Performs the first step of QMsm initialization by assigning the initial pseudostate to the currently active state of the state machine.

Parameters

[in,out]	me	pointer (see Object Orientation)
[in]	initial	the top-most initial transition for the MSM.

Note

Must be called only ONCE before QHSM_INIT().

QMsm inherits QHsm, so by the Object Orientation convention it should call the constructor of the superclass, i.e., QHsm_ctor(). However, this would pull in the QHsmVtable, which in turn will pull in the code for QHsm_init_() and QHsm_dispatch_() implemetations. To avoid this code size penalty, in case QHsm is not used in a given project, the QMsm_ctor() performs direct intitialization of the Vtable, which avoids pulling in the code for QMsm.

Usage

The following example illustrates how to invoke QMsm_ctor() in the "constructor" of a derived state machine:

void Calc_ctor(Calc * const me) {
    /* superclass' ctor */
    QMsm_ctor(&me->super, Q_STATE_CAST(&Calc_initial));
 
    me->operand1 = 0.0;
    me->operand2 = 0.0;
    me->len      = 0U;
    me->opKey    = 0U;
}

Definition at line 119 of file qep_msm.c.

QMsm_isInState()

bool QMsm_isInState	(	QMsm const *const	me,
		QMState const *const	state
	)

Description

Tests if a state machine derived from QMsm is-in a given state.

Note

For a MSM, to "be-in" a state means also to "be-in" a superstate of of the state.

Parameters

[in]	me	pointer (see Object Orientation)
[in]	state	pointer to the QMState object that corresponds to the tested state.

Returns

'true' if the MSM "is in" the state and 'false' otherwise

Definition at line 557 of file qep_msm.c.

QMsm_childStateObj_()

QMState const* QMsm_childStateObj_	(	QMsm const *const	me,
		QMState const *const	parent
	)

Description

Finds the child state of the given parent, such that this child state is an ancestor of the currently active state. The main purpose of this function is to support shallow history transitions in state machines derived from QMsm.

Parameters

[in]	me	pointer (see Object Orientation)
[in]	parent	pointer to the state-handler object

Returns

the child of a given parent state, which is an ancestor of the currently active state. For the corner case when the currently active state is the given parent state, function returns the parent state.

See also

QMsm_childStateObj()

Postcondition

the child must be found

Definition at line 588 of file qep_msm.c.

Variable Documentation

l_msm_top_s

struct QMState const l_msm_top_s

static

Initial value:

= {
    (struct QMState *)0,
    Q_STATE_CAST(0),
    Q_ACTION_CAST(0),
    Q_ACTION_CAST(0),
 
}

Definition at line 1 of file qep_msm.c.