kernel.h

来自「TCP-IP红宝书源代码」· C头文件 代码 · 共 84 行

/* kernel.h - disable, enable, halt, restore, isodd, min, max */

#include <stdlib.h>

/* Symbolic constants used throughout Xinu */

typedef	char		Bool;		/* Boolean type			*/
#define	FALSE		0		/* Boolean constants		*/
#define	TRUE		1
#define	EMPTY		(-1)		/* an illegal gpq		*/
#define	NULL		0		/* Null pointer for linked lists*/
#define	NULLCH		'\0'		/* The null character		*/
#define	NULLSTR		""		/* Pointer to empty string	*/
#define	SYSCALL		int		/* System call declaration	*/
#define	LOCAL		static 		/* Local procedure declaration	*/
#define	COMMAND		int		/* Shell command declaration	*/
#define	BUILTIN		int		/* Shell builtin " "		*/
#define	INTPROC		void		/* Interrupt procedure  "	*/
#define	PROCESS		int		/* Process declaration		*/
#define	RESCHYES	1		/* tell	ready to reschedule	*/
#define	RESCHNO		0		/* tell	ready not to resch.	*/
#define	MININT		0x80000000
#define	MAXINT		0x7fffffff
#define	LOWBYTE		0377		/* mask for low-order 8 bits	*/
#define	HIBYTE		0177400		/* mask for high 8 of 16 bits	*/
#define	LOW16		0177777		/* mask for low-order 16 bits	*/
#define	MINSTK		3072		/* minimum process stack size	*/
#define	NULLSTK		MINSTK		/* process 0 stack size		*/
#define	MAGIC		0125251		/* unusual value for top of stk	*/

/* Universal return constants */

#define	OK		 1		/* system call ok		*/
#define	SYSERR		-1		/* system call failed		*/
#define	EOF		-2		/* End-of-file (usu. from read)	*/
#define	TIMEOUT		-3		/* time out  (usu. recvtim)	*/
#define	INTRMSG		-4		/* keyboard "intr" key pressed	*/
					/*  (usu. defined as ^B)	*/
#define	BLOCKERR	-5		/* non-blocking op would block	*/

/* Initialization constants */

#define	INITSTK		1024		/* initial process stack size	*/
#define	INITPRIO	20		/* initial process priority	*/
#define	INITNAME	"main"		/* initial process name		*/
#define	INITARGS	1,0		/* initial count/arguments	*/
#define	INITRET		userret		/* processes return address	*/
#define	INITREG		0		/* initial register contents	*/
#define	QUANTUM		10		/* clock ticks until preemption	*/



/* Machine size definitions						*/

typedef	char	CHAR;		/* sizeof the unit the holds a character*/
typedef	int	WORD;		/* maximum of (int, char *)		*/
typedef	char	*PTR;		/* sizeof a char. or fcnt. pointer 	*/
typedef int	INT;		/* sizeof compiler integer		*/
typedef	int	REG;		/* sizeof machine register		*/

#define MAXLONG		0x7fffffff	
#define MINLONG		0x80000000

typedef short	STATWORD[1];	/* machine status for disable/restore	*/
				/* by declaring it to be an array, the	*/
				/* name provides an address so forgotten*/
				/* &'s don't become a problem		*/

/* Miscellaneous utility inline functions */
#define	isodd(x)	(01&(WORD)(x))
#define	min(a,b)	( (a) < (b) ? (a) : (b) )
#define	max(a,b)	( (a) > (b) ? (a) : (b) )

extern	int	rdyhead, rdytail;

extern	int	preempt;

extern int noint;

void	disable(STATWORD), restore(STATWORD);
void	kprintf(const char *, ...);
void	panic(const char *, ...);
SYSCALL	getpid(void);