完整的Bell实验室的嵌入式文件系统TFS

				#include "config.h"				#include "cpu.h"				#include "genlib.h"				#include "stddefs.h"								extern  int getopt(), atoi(), printf();				extern  void InitUART();												void    mstatshow(void);				static  ushort  MonitorSTATUS;								void				trap_exception(void)				{				    register int d2, d3, d4, d5, d6, d7; 				    register int *a2, *a3, *a4, *a5, *a6; 								    d2 = 0xDDDD2222;				    d3 = 0xDDDD3333;				    d4 = 0xDDDD4444;				    d5 = 0xDDDD5555;				    d6 = 0xDDDD6666;				    d7 = 0xDDDD7777;				    a2 = (int *)0xAAAA2222;				    a3 = (int *)0xAAAA3333;				    a4 = (int *)0xAAAA4444;				    a5 = (int *)0xAAAA5555;				    a6 = (int *)0xAAAA6666;								    printf("Trap exception around 0x%lx\n",(ulong)trap_exception);				    asm(" trap #3 ");				}								char *MstatHelp[] = {				    "Monitor status",				    "-[b:]",				    " -b {baud}  set baud rate",				    " -x         trap #3 exception",				    0,				};								int				Mstat(int argc,char *argv[])				{				    int opt;								    /* If no args, just dump current status. */				    if (argc == 1) {				        mstatshow();				        return(0);				    }								    while ((opt=getopt(argc,argv,"b:x")) != -1) {				        switch(opt) {				        case 'b':				            InitUART(atoi(optarg));				            break;				        case 'x':				            trap_exception();				            break;				        default:				            return(0);				        }				    }				    if (argc != optind)				        return(-1);				    return(0);				}								void				InitMonSTATUS(ulong state)				{				    extern void putsr(ushort);								    MonitorSTATUS = state;				    putsr((ushort)MonitorSTATUS);				}								void				SetMonSTATUS(void)				{				    extern void putsr(ushort);								    putsr((ushort)MonitorSTATUS);				}								void				mstatshow(void)				{				    extern  ulong getsr(void);				    extern  ulong getsp(void);				    				    monHeader(0);				    mstatshowcom();				    printf("Monitor SR: 0x%04x\n",(ushort)getsr());				    printf("Monitor SP: 0x%08x\n",getsp());				}