/*
This compilation (the Software) and all contributions by 
Benjamin Holt is hereby donated to the public domain

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.
 */

#ifndef _BIT_HELPERS_H_
#define _BIT_HELPERS_H_ 1

/* From <http://www.thescripts.com/forum/thread216333.html> */
/* Binary constant generator macro
By Tom Torfs - donated to the public domain
*/

/* All macro's evaluate to compile-time constants */

/* turn a numeric literal into a hex constant
(avoids problems with leading zeroes)
8-bit constants max value 0x11111111, always fits in unsigned long
*/
#define HEX__(n) 0x##n##LU

/* 8-bit conversion function */
#define B8__(x) ((x&0x0000000FLU)?1:0)	\
  +((x&0x000000F0LU)?2:0)\
  +((x&0x00000F00LU)?4:0)\
  +((x&0x0000F000LU)?8:0)\
  +((x&0x000F0000LU)?16:0)\
  +((x&0x00F00000LU)?32:0)\
  +((x&0x0F000000LU)?64:0)\
  +((x&0xF0000000LU)?128:0)

// ENHANCEME: a nybble version could be nice, too

/* for up to 8-bit binary constants */
#define B8(d) ((unsigned char)B8__(HEX__(d)))

/* for up to 16-bit binary constants, MSB first */
#define B16(dmsb,dlsb) (((unsigned short)B8(dmsb)<<8)\
			+ B8(dlsb))

/* for up to 32-bit binary constants, MSB first */
#define B32(dmsb,db2,db3,dlsb) (((unsigned long)B8(dmsb)<<24) \
				+ ((unsigned long)B8(db2)<<16) \
				+ ((unsigned long)B8(db3)<<8) \
				+ B8(dlsb))

 /* Sample usage:
B8(01010101) = 85
B16(10101010,01010101) = 43605
B32(10000000,11111111,10101010,01010101) = 2164238933
 */


#include <inttypes.h>
#define bit_set_8(var, mask)   ((var) |= (uint8_t)(mask))
#define bit_clear_8(var, mask)   ((var) &= (uint8_t)~(mask))
#define bit_toggle_8(var, mask)   ((var) ^= (uint8_t)(mask))
#define bit_read_8(var, mask)   ((var) & (uint8_t)(mask))
#define bit_assign_8(var, val, mask)   ((var) = (((var)&~(uint8_t)(mask))|((val)&(uint8_t)(mask))))

#define bit_set_16(var, mask)   ((var) |= (uint16_t)(mask))
#define bit_clear_16(var, mask)   ((var) &= (uint16_t)~(mask))
#define bit_toggle_16(var, mask)   ((var) ^= (uint16_t)(mask))
#define bit_read_16(var, mask)   ((var) & (uint16_t)(mask))
#define bit_assign_16(var, val, mask)   ((var) = (((var)&~(uint16_t)(mask))|((val)&(uint16_t)(mask))))

 // 32 bit versions here

 // Shorter named versions for the common operation.
#define bit_set(var, mask)   bit_set_8(var, mask)
#define bit_clear(var, mask) bit_clear_8(var, mask)
#define bit_toggle(var, mask) bit_toggle_8(var, mask)
#define bit_read(var, mask) bit_read_8(var, mask)
#define bit_assign(var, val, mask) bit_assign_8(var, val, mask)

#define BIT(x)   (1 << (x))  // replacement for the poorly named _BV
#define LONGBIT(x)   ((uint32_t)1 << (x))

#endif // _BIT_HELPERS_H_