si_ops.c

是一个手机功能的模拟程序

/*
 * Copyright (C) Ericsson Mobile Communications AB, 2000.
 * Licensed to AU-System AB.
 * All rights reserved.
 *
 * This software is covered by the license agreement between
 * the end user and AU-System AB, and may be used and copied
 * only in accordance with the terms of the said agreement.
 *
 * Neither Ericsson Mobile Communications AB nor AU-System AB
 * assumes any responsibility or liability for any errors or inaccuracies in
 * this software, or any consequential, incidental or indirect damage arising
 * out of the use of the Generic WAP Client software.
 */
#include "si_ops.h"

#include "si_types.h"
#include "si_misc.h"

/*==========================================
	OpS_New
============================================

---Purpose: 
To create and initialise an operand stack.
      
---Params:

               
---Return:
pstructOpS		the created OpS	
NULL					something went wrong

------------------------------------------------------------------------*/
pstructOpS OpS_New( VOID )
{
	pstructOpS	ops = NEWSTRUCT( structOpS );

	if (ops != NULL) {
		f_lh_newhead( &(ops->head) );

		if (ops->head == NULL) {
			DEALLOC( &ops );
		}
	}

	return ops;
}



/*==========================================
	OpS_NewFromOpS
============================================

---Purpose: 
To create and initialise an operand stack. The created OpS is initialised by moving entries from
another OpS.
      
---Params:
src						The OpS to move from
nbrToCopy			how many entries from the top of the stack to be moved.
								If -1 is passed in this argument all entries from src are moved.
               
---Return:
pstructOpS		the created OpS	
NULL					something went wrong

------------------------------------------------------------------------*/
pstructOpS OpS_NewFromOpS( pstructOpS src, INT16 nbrToMove )
/* nbrToMove == -1 means the whole OpS */
/* NULL is returned if something went wrong (e.g. nbrToMove > topIndex of src) */
{
	pstructOpS		result = NULL;
	t_link				link;
	UINT16				i;
	
	
	if (src == NULL)
		return NULL;

	if (nbrToMove == -1)
		nbrToMove = OpS_GetTopIndex(src);

	if (nbrToMove > OpS_GetTopIndex(src)) /* can't move more than the src holds */
		return NULL;

	result = OpS_New();
	if (result != NULL) {
		i = 0;
		while (i < nbrToMove) {
			link = f_lh_last( src->head );
			f_lh_out( &link );
			f_lh_into_as_first( &link, &(result->head) );
				/* the entries must be in the same order as in the src stack. 
					Therfore the entries are taken from the back and put in at the front.*/
			i++;
		}
	}
	return result;
}


/*==========================================
	OpS_NewFromOpS
============================================

---Purpose: 
To create and initialise an operand stack. The created OpS is initialised 
by copying entries from another OpS.
      
---Params:
src						The OpS to copy from
nbrToCopy			how many entries from the top of the stack to be copied.
								If -1 is passed in this argument all entries from src are copied.
               
---Return:
pstructOpS		the created OpS	
NULL					something went wrong

------------------------------------------------------------------------*/
VOID OpS_Delete( pstructOpS *pThis )
{
	t_link				link;
	pstructVar		aVar;

	if (*pThis != NULL) {
		while ( ! f_lh_empty((*pThis)->head) ) {
			link = f_lh_last((*pThis)->head);
			aVar = (pstructVar) link->data;
			Var_Delete( &aVar );
			f_lh_disposelink( &link );
		}
		f_lh_disposehead( &((*pThis)->head) );

		DEALLOC( pThis );
	}
}



/*==========================================
	OpS_Push
============================================

---Purpose: 
To push a var on an OpS.
	
---Params:
thisx			the OpS to operate on
pVar			the var to be push.
						The reference will afterwards be set to NULL to avoid
						misuse of the reference.
	
---Return:

------------------------------------------------------------------------*/
VOID OpS_Push( pstructOpS thisx, pstructVar *pVar )
{
	t_link	newEl = NULL;

	if ((thisx != NULL) && (*pVar != NULL)) {
		f_lh_newlink( &newEl );
		if (newEl != NULL) {
			newEl->data = *pVar;
			*pVar = NULL; /* so that the reference is not used by mistake somewhere else */
			f_lh_into( &newEl, &(thisx->head) );
		}
	}
}


/*==========================================
	OpS_Pop
============================================

---Purpose: 
To pop a var from an OpS.
	
---Params:
thisx					the OpS to operate on
	
---Return:
pstructVar		the top stack element
NULL					the stack is empty 

------------------------------------------------------------------------*/
pstructVar OpS_Pop( pstructOpS thisx )
{
	t_link				link;
	pstructVar		res = NULL;

	link = f_lh_last(thisx->head);
	if (link != NULL) {
		res = (pstructVar) link->data;
		f_lh_disposelink( &link );
	}

	return res;
}



/*==========================================
	OpS_GetTopIndex
============================================

---Purpose: 
To get the index of the top element 
(i.e. how many elements are in the stack).
Example: If one element is is the stack the topindex is 1.
If the stack is empty zero is returned.
	
---Params:
thisx					the OpS to operate on
	
---Return:
UINT16				the index of the top stack element

------------------------------------------------------------------------*/
UINT16 OpS_GetTopIndex( pstructOpS thisx )
/* top index is 0 if the stack is empty  */
{ 
	UINT16	res = 0;

	if (thisx != NULL) {
		if (thisx->head != NULL) {
			res = f_lh_cardinal( thisx->head );
		}
	}

	return res;
}


/*==========================================
	OpS_ClearUntilIndex
============================================

---Purpose: 
To pop stack entries until there is <index> entries left in the stack.
(Needed for cleaning up the OpS after upon function return statement)
	
---Params:
thisx					the OpS to operate on
index					which index the top entry in the stack must have after 
								the operation is done
	
---Return:
TRUE					the operation was successful
FALSE					the operation failed (e.g. less than <index> entries in the stack)

------------------------------------------------------------------------*/
BOOL OpS_ClearUntilIndex( pstructOpS thisx, UINT16 index )
{
	UINT16			topIndex = OpS_GetTopIndex(thisx);
	UINT16			nbrOfElToPop;
	UINT16			i;
	pstructVar	aVar;

	if (index > topIndex) {
		return FALSE;
	}
	else {
		nbrOfElToPop = topIndex - index;

		i=0;
		while (i < nbrOfElToPop) {
			aVar = OpS_Pop( thisx );
			Var_Delete( &aVar );
			i++;
		}

		return TRUE;
	}
}



/*==========================================
	OpS_NewFromArgString
============================================

---Purpose: 

	
---Params:

               
---Return:


------------------------------------------------------------------------*/
/* the states needed to parse the argstring */
typedef enum {
	argstate_start,
	argstate_nextOrDone,
	argstate_next,
	argstate_invalid,
	argstate_true,
	argstate_false,
	argstate_string,
	argstate_number,
	argstate_done,
	argstate_error
} enumArgState;


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


pstructOpS OpS_NewFromArgString( WCHAR* argString )
/*
The argString must start with a '(' and then ends parsing when ')' is found
*/