/* Testprogram for accessing struct in flash memory
	MRU JR 091105

*/
#include <inttypes.h>
#include <avr/pgmspace.h>

typedef uint8_t (*PROCFNP)(char *);

typedef struct namefnpntr
{	PGM_P		namestr;
	PROCFNP	procfnp;
} NAMEFNPNTR;

/* functions for evaluating the GPS sentences */

uint8_t procPGALM(char *str)
{	
	return 0;
}

uint8_t procPGRMC(char *str)
{
	return 0;
}
uint8_t procPGRMC1(char *str)
{
	return 0;
}
uint8_t procPGRMI(char *str)
{
	return 0;
}
uint8_t procPGRMO(char *str)
{
	return 0;
}

/* Strings in program memory */
const char PROGMEM pgmPGALM[] 	= "PGALM";
const char PROGMEM pgmPGRMC[] 	= "PGRMC";
const char PROGMEM pgmPGRMC1[] 	= "PGRMC1";
const char PROGMEM pgmPGRMI[] 	= "PGRMI";
const char PROGMEM pgmPGRMO[] 	= "PGRMO";

/* Table in flash memory */

const NAMEFNPNTR namefntab[] PROGMEM =
 	{	{pgmPGALM, 	procPGALM},
		{pgmPGRMC, 	procPGRMC},
		{pgmPGRMC1, procPGRMC1},
		{pgmPGRMI, 	procPGRMI},
		{pgmPGRMO, 	procPGRMO}
	};

#define NAMEFNCNT 5

int8_t procGPS(char *chrp, NAMEFNPNTR *namefnp)
{	uint8_t i;
/* pointer to current struct in name/func table */
	void		*pgmp;
	PROCFNP	procfnpntr;

/* search the table for the sentence name, note that the table is
	in the program space 
*/	
	for (i = 0; i < NAMEFNCNT; i++)
	{ pgmp = (void *) pgm_read_word(&(namefnp[i].namestr[0]));
		if (strcmp_P(&chrp[1], pgmp) != 0)		/* sentence name starts at 1 */
		{	pgmp = (void *) &namefnp[i].procfnp;
			procfnpntr = 
				(PROCFNP) pgm_read_word(pgmp);
			return procfnpntr(chrp);	/* process the sentence */
		}
	}	/* for table entry */

	return 0;
}

/* global variable */
char RXstr[82] = "$GPRMC,235958,A,5007.0000,N,0830.0000,E,"
		"005.1,010.2,311208,002.3,W,A*1B\r\n";

int main(void)
{	
	(void) procGPS(RXstr, (NAMEFNPNTR *) &namefntab);

	return 0;
}