/*  * 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. */ /* * functions for running the debugged process */ #include "defs.h"#include "fns.h"  int child;int msgfd = -1;int notefd = -1;int pcspid = -1;int pcsactive = 0; voidsetpcs(void){	char buf[128]; 	if(pid && pid != pcspid){		if(msgfd >= 0){			close(msgfd);			msgfd = -1;		}		if(notefd >= 0){			close(notefd);			notefd = -1;		}		pcspid = -1;		sprint(buf, "/proc/%d/ctl", pid);		msgfd = open(buf, OWRITE);		if(msgfd < 0)			error("can't open control file");		sprint(buf, "/proc/%d/note", pid);		notefd = open(buf, ORDWR);		if(notefd < 0)			error("can't open note file");		pcspid = pid;	}} voidmsgpcs(char *msg){	char err[ERRMAX]; 	setpcs();	if(write(msgfd, msg, strlen(msg)) < 0 && !ending){		errstr(err, sizeof err);		if(strcmp(err, "interrupted") != 0)			endpcs();		errors("can't write control file", err);	}} /* * empty the note buffer and toss pending breakpoint notes */voidunloadnote(void){	char err[ERRMAX]; 	setpcs();	for(; nnote<NNOTE; nnote++){		switch(read(notefd, note[nnote], sizeof note[nnote])){		case -1:			errstr(err, sizeof err);			if(strcmp(err, "interrupted") != 0)				endpcs();			errors("can't read note file", err);		case 0:			return;		}		note[nnote][ERRMAX-1] = '\0';		if(strncmp(note[nnote], "sys: breakpoint", 15) == 0)			--nnote;	}} /* * reload the note buffer */voidloadnote(void){	int i;	char err[ERRMAX]; 	setpcs();	for(i=0; i<nnote; i++){		if(write(notefd, note[i], strlen(note[i])) < 0){			errstr(err, sizeof err);			if(strcmp(err, "interrupted") != 0)				endpcs();			errors("can't write note file", err);		}	}	nnote = 0;} voidnotes(void){	int n; 	if(nnote == 0)		return;	dprint("notes:\n");	for(n=0; n<nnote; n++)		dprint("%d:\t%s\n", n, note[n]);} voidkillpcs(void){	msgpcs("kill");} voidgrab(void){	flush();	msgpcs("stop");	bpwait();} voidungrab(void){	msgpcs("start");} voiddoexec(void){	char *argl[MAXARG];	char args[LINSIZ];	char *p;	char **ap;	char *thisarg; 	ap = argl;	p = args;	*ap++ = symfil;	for (rdc(); lastc != EOR;) {		thisarg = p;		if (lastc == '<' || lastc == '>') {			*p++ = lastc;			rdc();		}		while (lastc != EOR && lastc != SPC && lastc != TB) {			*p++ = lastc;			readchar();		}		if (lastc == SPC || lastc == TB)			rdc();		*p++ = 0;		if (*thisarg == '<') {			close(0);			if (open(&thisarg[1], OREAD) < 0) {				print("%s: cannot open\n", &thisarg[1]);				_exits(0);			}		}		else if (*thisarg == '>') {			close(1);			if (create(&thisarg[1], OWRITE, 0666) < 0) {				print("%s: cannot create\n", &thisarg[1]);				_exits(0);			}		}		else			*ap++ = thisarg;	}	*ap = 0;	exec(symfil, argl);	perror(symfil);} char	procname[100]; voidstartpcs(void){	if ((pid = fork()) == 0) {		pid = getpid();		msgpcs("hang");		doexec();		exits(0);	} 	if (pid == -1)		error("can't fork");	child++;	sprint(procname, "/proc/%d/mem", pid);	corfil = procname;	msgpcs("waitstop");	bpwait();	if (adrflg)		rput(cormap, mach->pc, adrval);	while (rdc() != EOR)		;	reread();} voidrunstep(uvlong loc, int keepnote){	int nfoll;	uvlong foll[3];	BKPT bkpt[3];	int i; 	if(machdata->foll == 0){		dprint("stepping unimplemented; assuming not a branch\n");		nfoll = 1;		foll[0] = loc+mach->pcquant;	}else {		nfoll = machdata->foll(cormap, loc, rget, foll);		if (nfoll < 0)			error("%r");	}	memset(bkpt, 0, sizeof bkpt);	for(i=0; i<nfoll; i++){		if(foll[i] == loc)			error("can't single step: next instruction is dot");		bkpt[i].loc = foll[i];		bkput(&bkpt[i], 1);	}	runrun(keepnote);	for(i=0; i<nfoll; i++)		bkput(&bkpt[i], 0);} voidbpwait(void){	setcor();	unloadnote();} voidrunrun(int keepnote){	int on; 	on = nnote;	unloadnote();	if(on != nnote){		notes();		error("not running: new notes pending");	}	if(keepnote)		loadnote();	else		nnote = 0;	flush();	msgpcs("startstop");	bpwait();} voidbkput(BKPT *bp, int install){	char buf[256];	ADDR loc;	int ret; 	errstr(buf, sizeof buf);	if(machdata->bpfix)		loc = (*machdata->bpfix)(bp->loc);	else		loc = bp->loc;	if(install){		ret = get1(cormap, loc, bp->save, machdata->bpsize);		if (ret > 0)			ret = put1(cormap, loc, machdata->bpinst, machdata->bpsize);	}else		ret = put1(cormap, loc, bp->save, machdata->bpsize);	if(ret < 0){		sprint(buf, "can't set breakpoint at %#llux: %r", bp->loc);		print(buf);		read(0, buf, 100);	}}