/*  * This file is part of the UCB release of Plan 9. It is subject to the license * terms in the LICENSE file found in the top-level directory of this * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No * part of the UCB release of Plan 9, including this file, may be copied, * modified, propagated, or distributed except according to the terms contained * in the LICENSE file. */ /* * *	debugger * */ #include "defs.h"#include "fns.h" char	BADEQ[] = "unexpected `='"; BOOL	executing;extern	Rune	*lp; char	eqformat[ARB] = "z";char	stformat[ARB] = "zMi"; ADDR	ditto; ADDR	dot;int	dotinc;WORD	adrval, cntval, loopcnt;int	adrflg, cntflg; /* command decoding */ command(char *buf, int defcom){	char	*reg;	char	savc;	Rune	*savlp=lp;	char	savlc = lastc;	char	savpc = peekc;	static char lastcom = '=', savecom = '='; 	if (defcom == 0)		defcom = lastcom;	if (buf) {		if (*buf==EOR)			return(FALSE);		clrinp();		lp=(Rune*)buf;	}	do {		adrflg=expr(0);		/* first address */		if (adrflg){			dot=expv;			ditto=expv;		}		adrval=dot; 		if (rdc()==',' && expr(0)) {	/* count */			cntflg=TRUE;			cntval=expv;		} else {			cntflg=FALSE;			cntval=1;			reread();		} 		if (!eol(rdc()))			lastcom=lastc;		/* command */		else {			if (adrflg==0)				dot=inkdot(dotinc);			reread();			lastcom=defcom;		}		switch(lastcom) {		case '/':		case '=':		case '?':			savecom = lastcom;			acommand(lastcom);			break; 		case '>':			lastcom = savecom; 			savc=rdc();			if (reg=regname(savc))				rput(cormap, reg, dot);			else					error("bad variable");			break; 		case '!':			lastcom=savecom;			shell(); 			break; 		case '$':			lastcom=savecom;			printtrace(nextchar()); 			break; 		case ':':			if (!executing) { 				executing=TRUE;				subpcs(nextchar());				executing=FALSE;				lastcom=savecom;			}			break; 		case 0:			prints(DBNAME);			break; 		default: 			error("bad command");		}		flushbuf();	} while (rdc()==';');	if (buf == 0)		reread();	else {		clrinp();		lp=savlp;		lastc = savlc;		peekc = savpc;	} 	if(adrflg)		return dot;	return 1;} /* * [/?][wml] */ voidacommand(int pc){	int eqcom;	Map *map;	char *fmt;	char buf[512]; 	if (pc == '=') {		eqcom = 1;		fmt = eqformat;		map = dotmap;	} else {		eqcom = 0;		fmt = stformat;		if (pc == '/')			map = cormap;		else			map = symmap;	}	if (!map) {		snprint(buf, sizeof(buf), "no map for %c", pc);		error(buf);	} 	switch (rdc())	{	case 'm':		if (eqcom)			error(BADEQ); 		cmdmap(map);		break; 	case 'L':	case 'l':		if (eqcom)			error(BADEQ); 		cmdsrc(lastc, map);		break; 	case 'W':	case 'w':		if (eqcom)			error(BADEQ); 		cmdwrite(lastc, map);		break; 	default:		reread();		getformat(fmt);		scanform(cntval, !eqcom, fmt, map, eqcom);	}} voidcmdsrc(int c, Map *map){	ulong w;	long locval, locmsk;	ADDR savdot;	ushort sh;	char buf[512];	int ret; 	if (c == 'L')		dotinc = 4;	else		dotinc = 2;	savdot=dot;	expr(1); 	locval=expv;	if (expr(0))		locmsk=expv; 	else		locmsk = ~0;	if (c == 'L')		while ((ret = get4(map, dot, &w)) > 0 &&  (w&locmsk) != locval)			dot = inkdot(dotinc);	else		while ((ret = get2(map, dot, &sh)) > 0 && (sh&locmsk) != locval)			dot = inkdot(dotinc);	if (ret < 0) { 		dot=savdot; 		error("%r");	}	symoff(buf, 512, dot, CANY);	dprint(buf);} static char badwrite[] = "can't write process memory or text image"; voidcmdwrite(int wcom, Map *map){	ADDR savdot;	char *format;	int pass; 	if (wcom == 'w')		format = "x";	else		format = "X";	expr(1);	pass = 0;	do {		pass++;  		savdot=dot;		exform(1, 1, format, map, 0, pass);		dot=savdot;		if (wcom == 'W') {			if (put4(map, dot, expv) <= 0)				error(badwrite);		} else {			if (put2(map, dot, expv) <= 0)				error(badwrite);		}		savdot=dot;		dprint("=%8t"); 		exform(1, 0, format, map, 0, pass);		newline();	} while (expr(0));	dot=savdot;} /* * collect a register name; return register offset * this is not what i'd call a good division of labour */ char *regname(int regnam){	static char buf[64];	char *p;	int c; 	p = buf;	*p++ = regnam;	while (isalnum(c = readchar())) {		if (p >= buf+sizeof(buf)-1)			error("register name too long");		*p++ = c;	}	*p = 0;	reread();	return (buf);} /* * shell escape */ voidshell(void){	int	rc, unixpid;	char *argp = (char*)lp; 	while (lastc!=EOR)		rdc();	if ((unixpid=fork())==0) {		*lp=0;		execl("/bin/rc", "rc", "-c", argp, nil);		exits("execl");				/* botch */	} else if (unixpid == -1) {		error("cannot fork");	} else {		mkfault = 0;		while ((rc = waitpid()) != unixpid){			if(rc == -1 && mkfault){				mkfault = 0;				continue;			}			break;		}		prints("!"); 		reread();	}}