#include <u.h>#include <libc.h>#include "dosfs.h" enum {	Npart	= 32, 	Data	= 0,	Ctl	= 1,}; typedef struct Dev Dev;struct Dev{	char	dev[16];	int	fd[2];	uint	ss;	uvlong	lba;}; #define	dprint(...)		do{}while(0) intmbrread(Dev *d, uvlong sec, void *buf){	uchar *u; 	if(d->ss < 0x200)		return -1;	if(pread(d->fd[Data], buf, d->ss, d->ss*sec) != d->ss)		return -1;	u = buf; 	if(u[0x1fe] != 0x55 || u[0x1ff] != 0xaa)		return -1;	return 0;} intsecread(Dev *d, uvlong sec, void *buf){	if(pread(d->fd[Data], buf, d->ss, d->ss*sec) != d->ss)		return -1;	return 0;} voidaddpart(Dev *d, char *part, uvlong start, uvlong end){	dprint("%s: part %s %lld %lld\n", d->dev, part, start, end);	if(fprint(d->fd[Ctl], "part %s %lld %lld\n", part, start, end) <= 0)		fprint(2, "addpart: %s: %r\n", d->dev);} static intp9part(Dev *d, uvlong sec, char*, char *buf){	char *field[4], *line[Npart+1];	uvlong start, end;	int i, n; 	dprint("p9part %lld\n", sec);	if(secread(d, sec+1, buf))		return -1;	buf[d->ss-1] = '\0';	if(strncmp(buf, "part ", 5))		return -1; 	n = getfields(buf, line, Npart+1, 1, "\n");	dprint("p9part %d lines..", n);	if(n == 0)		return -1;	for(i = 0; i < n; i++){		if(strncmp(line[i], "part ", 5) != 0)			break;		if(getfields(line[i], field, 4, 0, " ") != 4)			break;		start = strtoull(field[2], 0, 0);		end = strtoull(field[3], 0, 0);		if(start >= end || end > d->lba)			break;		addpart(d, field[1], sec+start, sec+end);	}	return 0;} intisdos(int t){	return t==FAT12 || t==FAT16 || t==FATHUGE || t==FAT32 || t==FAT32X;} intisextend(int t){	return t==EXTEND || t==EXTHUGE || t==LEXTEND;} static intmbrpart(Dev *d, uvlong sec, char *mbr, char *part){	char name[10];	int ndos, i, nplan9;	ulong start, end;	ulong firstx, nextx, npart;	Dospart *dp;	int (*repart)(Dev*, uvlong, char*, char*); 	sec = 0;	dp = (Dospart*)&mbr[0x1BE]; 	/* get the MBR (allowing for DMDDO) */	if(mbrread(d, sec, mbr))		return -1;	for(i=0; i<4; i++)		if(dp[i].type == DMDDO) {			dprint("DMDDO %d\n", i);			sec = 63;			if(mbrread(d, sec, mbr))				return -1;			i = -1;	/* start over */		} 	/*	 * Read the partitions, first from the MBR and then	 * from successive extended partition tables.	 */	nplan9 = 0;	ndos = 0;	firstx = 0;	for(npart=0;;) {		if(mbrread(d, sec, mbr) != 0)			return -1;		if(firstx)			dprint("%s ext %llud ", d->dev, sec);		else			dprint("%s mbr ", d->dev);		nextx = 0;		for(i=0; i<4; i++) {			start = sec+GLONG(dp[i].start);			end = start+GLONG(dp[i].len);			if(dp[i].type == 0 && start == 0 && end == 0){				if(i == 0)					return -1;				continue;			}			dprint("type %x [%ld, %ld)", dp[i].type, start, end);			repart = 0;			if(dp[i].type == PLAN9) {				if(nplan9 == 0)					snprint(name, sizeof name, "plan9");				else					snprint(name, sizeof name, "plan9.%d", nplan9);				repart = p9part;				nplan9++;			}else if(!ndos && isdos(dp[i].type)){				ndos = 1;				strcpy(name, "dos");			}else				snprint(name, sizeof name, "%ld", npart);			npart++;			if(end != 0){				dprint(" %s..", name);				addpart(d, name, start, end);			}			if(repart)				repart(d, start, nil, part);						/* nextx is relative to firstx (or 0), not sec */			if(isextend(dp[i].type)){				nextx = start-sec+firstx;				dprint("link %lud...", nextx);			}		}		dprint("\n");		if(!nextx)			break;		if(!firstx)			firstx = nextx;		sec = nextx;	}		return 0;} voidpartition(Dev *d, uvlong lba){	char *m, *p; 	m = malloc(8192);	p = malloc(8192);	!mbrpart(d, lba, m, p) || p9part(d, lba, nil, p);	free(m);	free(p);} static intgetsize(Dev *d){	char *s0, *s, *p, *f[3];	int l, r; 	l = 1024;	/* #S/sdctl has 0 size; guess */	d->lba = 0;	d->ss = 512;	if((s0 = malloc(l + 1)) == nil)		return -1;	if((l = read(d->fd[Ctl], s0, l)) == -1){		free(s0);		return -1;	}	s0[l] = 0;	r = 0;	for(s = s0; p = strchr(s, '\n'); s = p + 1){		*p = 0;		if(tokenize(s, f, nelem(f)) < 1)			continue;		if(strcmp(f[0], "geometry") == 0){			d->lba = strtoull(f[1], nil, 0);			d->ss = strtoul(f[2], nil, 0);			dprint("%s geometry %llud %ud\n", d->dev, d->lba, d->ss);		}//		else if(strcmp(f[0], "part") == 0 && strcmp(f[1], "data") != 0)//			r = -1;	}	free(s0);	return r;} static voidpartitions0(char *s, int l){	char *p, *q, *f[3], buf[20];	int i;	Dev d; 	dprint("partitions0\n");	s[l] = 0;	for(; p = strchr(s, '\n'); s = p + 1){		*p = 0;		if(tokenize(s, f, nelem(f)) < 1)			continue;		for(i = 0; i < 0x10; i++){			snprint(buf, sizeof buf, "%s%xpart", f[0], i);			if((q = getenv(buf)) != nil){				free(q);				continue;			}			d.fd[0] = -1;			d.fd[1] = -1;			snprint(d.dev, sizeof d.dev, "#S/%s%x", f[0], i);			snprint(buf, sizeof buf, "%s/data", d.dev);			d.fd[0] = open(buf, OREAD);			if(d.fd[0] >= 0){				snprint(buf, sizeof buf, "%s/ctl", d.dev);				d.fd[1] = open(buf, ORDWR);			}			if(d.fd[0] >= 0 && d.fd[1] >= 0)			if(getsize(&d) != -1)				partition(&d, 0);			close(d.fd[0]);			close(d.fd[1]);		}	}} voidpartitions(void){	char *s;	int fd, l; 	fd = open("#S/sdctl", OREAD);	if(fd == -1)		return;	l = 1024;	/* #S/sdctl has 0 size; guess */	if(s = malloc(l + 1))	if((l = read(fd, s, l)) > 0)		partitions0(s, l);	free(s);	close(fd);}