/* General macros and constants used by the kernel. */
#ifndef CONST_H
#define CONST_H

#include <minix/config.h>
#include <minix/bitmap.h>

#include "config.h"

/* Map a process number to a privilege structure id. */
#define s_nr_to_id(n)	(NR_TASKS + (n) + 1)

/* Translate a pointer to a field in a structure to a pointer to the structure
 * itself. So it translates '&struct_ptr->field' back to 'struct_ptr'.
 */
#define structof(type, field, ptr) \
	((type *) (((char *) (ptr)) - offsetof(type, field)))

/* Translate an endpoint number to a process number, return success. */
#define isokendpt(e,p) isokendpt_d((e),(p),0)
#define okendpt(e,p)   isokendpt_d((e),(p),1)

/* Constants used in virtual_copy(). Values must be 0 and 1, respectively. */
#define _SRC_	0
#define _DST_	1

/* Number of random sources */
#define RANDOM_SOURCES	16

#define get_sys_bit(map,bit) \
	( MAP_CHUNK(map.chunk,bit) & (1 << CHUNK_OFFSET(bit) )
#define get_sys_bits(map,bit) \
	( MAP_CHUNK(map.chunk,bit) )
#define set_sys_bit(map,bit) \
	( MAP_CHUNK(map.chunk,bit) |= (1 << CHUNK_OFFSET(bit) )
#define unset_sys_bit(map,bit) \
	( MAP_CHUNK(map.chunk,bit) &= ~(1 << CHUNK_OFFSET(bit) )
#define NR_SYS_CHUNKS	BITMAP_CHUNKS(NR_SYS_PROCS)

#if DEBUG_LOCK_CHECK
#define reallock(c, v)  { if(intr_disabled()) { kinfo.relocking++; } else { intr_disable(); } }
#else
#define reallock(c, v)  intr_disable()
#endif

#define realunlock(c)   intr_enable()

#if DEBUG_TIME_LOCKS
#define lock(c, v)    do { reallock(c, v); locktimestart(c, v); } while(0)
#define unlock(c)     do { locktimeend(c); realunlock(c); } while(0)
#else
/* Disable/ enable hardware interrupts. The parameters of lock() and unlock()
 * are used when debugging is enabled. See debug.h for more information.
 */
#define lock(c, v)      reallock(c, v)
#define unlock(c)       realunlock(c)
#endif

/* args to intr_init() */
#define INTS_ORIG	0	/* restore interrupts */
#define INTS_MINIX	1	/* initialize interrupts for minix */

#endif /* CONST_H */