#ifndef CSE466_PROGSPACE_H
#define CSE466_PROGSPACE_H

/* Note that the cse466 prefix in here is to avoid 
 * namespace collisions with stuff in tinyos and in the
 * avr-gcc libraries used by tinyos
 */

#ifndef __CSE466_ATTR_PROGMEM__
#define __CSE466_ATTR_PROGMEM__ __attribute__((__progmem__))
#endif

#ifndef CSE466_PROGMEM
#define CSE466_PROGMEM __ATTR_PROGMEM__
#endif

/* some unsigned types for storage in program space */

/* an unsigned int in program space */
typedef unsigned int cse466_prog_uint CSE466_PROGMEM;

/* an unsigned char in program space */
typedef unsigned char cse466_prog_uchar CSE466_PROGMEM;




/* Use this just like a function.  
 * It returns the byte at addr in program memory
 */
#define cse466_pgm_read_byte(addr)          \
({                                          \
    uint16_t __addr16 = (uint16_t)(addr);   \
    uint8_t  __result;                      \
    __asm__                                 \
    (                                       \
        "lpm %A0, Z"   "\n\t"               \
        : "=r" (__result)                   \
        : "z" (__addr16)                    \
    );                                      \
    __result;                               \
})


/* Use this just like a function.
 * It returns the word at addr in program memory
 */
#define cse466_pgm_read_word(addr)          \
({                                          \
    uint16_t __addr16 = (uint16_t)(addr);   \
    uint16_t __result;                      \
    __asm__                                 \
    (                                       \
        "lpm %A0, Z+"   "\n\t"              \
        "lpm %B0, Z"    "\n\t"              \
        : "=r" (__result), "=z" (__addr16)  \
        : "1" (__addr16)                    \
    );                                      \
    __result;                               \
})


/*
An example of how to use this in tiny os:

Note that I'm only showing the implementation block,
and that I've copied the progspace.h file into 
the same directory as my nc files.

implementation {
  #include "progspace.h"

  cse466_prog_uint theInts[] = { 1, 2, 3, 4 };

  cse466_prog_uchar theChars[] = { 5, 6, 7, 8 };

  
  void read_the_ints() {
    int i;
	unsigned int value;
    for(i=0; i<4; i++) {
	
      // note that the compiler is smart enough to do this 
      // pointer arithmetic properly
      value = cse466_pgm_read_word(theInts + i);

	  // use value for whatever you want here
    }
  }

  void read_the_chars() {
    int i;
	unsigned char value;
    for(i=0; i<4; i++) {
      value = cse466_pgm_read_word(theChars + i);

	  // use value for whatever you want here
    }
  }
}
*/


#endif