#include <u.h>
#include <libc.h>
#include <bio.h>
#include <auth.h>
#include <fcall.h>
#include "iotrack.h"
#include "dat.h"
#include "fns.h"
static uchar isdos[256];
int
isdosfs(uchar *buf)
{
/*
* When dynamic disc managers move the disc partition,
* they make it start with 0xE9.
*/
if(buf[0] == 0xE9)
return 1;
/*
* Check if the jump displacement (magic[1]) is too short for a FAT.
* DOS 4.0 MBR has a displacement of 8.
*/
if(buf[0] == 0xEB && buf[2] == 0x90 && buf[1] != 0x08)
return 1;
return 0;
}
int
dosfs(Xfs *xf)
{
Iosect *p, *p1;
Dosboot *b;
Fatinfo *fi;
Dosboot32 *b32;
Dosbpb *bp;
long fisec, extflags;
int i;
if(!isdos['a']){
for(i = 'a'; i <= 'z'; i++)
isdos[i] = 1;
for(i = 'A'; i <= 'Z'; i++)
isdos[i] = 1;
for(i = '0'; i <= '9'; i++)
isdos[i] = 1;
isdos['$'] = 1;
isdos['%'] = 1;
isdos['''] = 1;
isdos['-'] = 1;
isdos['_'] = 1;
isdos['@'] = 1;
isdos['~'] = 1;
isdos['`'] = 1;
isdos['!'] = 1;
isdos['('] = 1;
isdos[')'] = 1;
isdos['{'] = 1;
isdos['}'] = 1;
isdos['^'] = 1;
isdos['#'] = 1;
isdos['&'] = 1;
}
p = getsect(xf, 0);
if(p == 0)
return -1;
b = (Dosboot*)p->iobuf;
if(isdosfs(p->iobuf) == 0){
putsect(p);
return -1;
}
bp = malloc(sizeof(Dosbpb));
memset(bp, 0, sizeof(Dosbpb)); /* clear lock */
xf->ptr = bp;
xf->fmt = 1;
bp->sectsize = GSHORT(b->sectsize);
bp->clustsize = b->clustsize;
bp->nresrv = GSHORT(b->nresrv);
bp->nfats = b->nfats;
bp->rootsize = GSHORT(b->rootsize);
bp->volsize = GSHORT(b->volsize);
if(bp->volsize == 0)
bp->volsize = GLONG(b->bigvolsize);
bp->mediadesc = b->mediadesc;
bp->fatsize = GSHORT(b->fatsize);
bp->fataddr = GSHORT(b->nresrv);
bp->fatinfo = 0;
if(bp->fatsize == 0){ /* is FAT32 */
if(chatty)
bootsecdump32(2, xf, (Dosboot32*)b);
xf->isfat32 = 1;
b32 = (Dosboot32*)b;
bp->fatsize = GLONG(b32->fatsize32);
if(bp->fatsize == 0){
putsect(p);
return -1;
}
bp->dataaddr = bp->fataddr + bp->nfats*bp->fatsize;
bp->rootaddr = 0;
bp->rootstart = GLONG(b32->rootstart);
/*
* disable fat mirroring?
*/
extflags = GSHORT(b32->extflags);
if(extflags & 0x0080){
for(i = 0; i < 4; i++){
if(extflags & (1 << i)){
bp->fataddr += i * bp->fatsize;
bp->nfats = 1;
break;
}
}
}
/*
* fat free list info
*/
bp->freeptr = FATRESRV;
fisec = GSHORT(b32->infospec);
if(fisec != 0 && fisec < GSHORT(b32->nresrv)){
p1 = getsect(xf, fisec);
if(p1 != nil){
fi = (Fatinfo*)p1->iobuf;
if(GLONG(fi->sig1) == FATINFOSIG1 && GLONG(fi->sig) == FATINFOSIG){
bp->fatinfo = fisec;
bp->freeptr = GLONG(fi->nextfree);
bp->freeclusters = GLONG(fi->freeclust);
chat("fat info: %ld free clusters, next free %ld\n", bp->freeclusters, bp->freeptr);
}
putsect(p1);
}
}
}else{
if(chatty)
bootdump(2, b);
bp->rootaddr = bp->fataddr + bp->nfats*bp->fatsize;
bp->rootstart = 0;
i = bp->rootsize*DOSDIRSIZE + bp->sectsize-1;
i /= bp->sectsize;
bp->dataaddr = bp->rootaddr + i;
bp->freeptr = FATRESRV;
}
bp->fatclusters = FATRESRV+(bp->volsize - bp->dataaddr)/bp->clustsize;
if(xf->isfat32)
bp->fatbits = 32;
else if(bp->fatclusters < 4087)
bp->fatbits = 12;
else
bp->fatbits = 16;
chat("fatbits=%d (%d clusters)...", bp->fatbits, bp->fatclusters);
for(i=0; i<b->nfats; i++)
chat("fat %d: %ld...", i, bp->fataddr+i*bp->fatsize);
chat("root: %ld...", bp->rootaddr);
chat("data: %ld...", bp->dataaddr);
putsect(p);
return 0;
}
/*
* initialize f to the root directory
* this file has no Dosdir entry,
* so we special case it all over.
*/
void
rootfile(Xfile *f)
{
Dosptr *dp;
dp = f->ptr;
memset(dp, 0, sizeof(Dosptr));
dp->prevaddr = -1;
}
int
isroot(ulong addr)
{
return addr == 0;
}
int
getfile(Xfile *f)
{
Dosptr *dp;
Iosect *p;
dp = f->ptr;
if(dp->p)
panic("getfile");
p = getsect(f->xf, dp->addr);
if(p == nil)
return -1;
/*
* we could also make up a Dosdir for the root
*/
dp->d = nil;
if(!isroot(dp->addr)){
if(f->qid.path != QIDPATH(dp)){
chat("qid mismatch f=%#llux d=%#lux...", f->qid.path, QIDPATH(dp));
putsect(p);
errno = Enonexist;
return -1;
}
dp->d = (Dosdir *)&p->iobuf[dp->offset];
}
dp->p = p;
return 0;
}
void
putfile(Xfile *f)
{
Dosptr *dp;
dp = f->ptr;
if(!dp->p)
panic("putfile");
putsect(dp->p);
dp->p = nil;
dp->d = nil;
}
long
getstart(Xfs *xf, Dosdir *d)
{
long start;
start = GSHORT(d->start);
if(xf->isfat32)
start |= GSHORT(d->hstart)<<16;
return start;
}
void
putstart(Xfs *xf, Dosdir *d, long start)
{
PSHORT(d->start, start);
if(xf->isfat32)
PSHORT(d->hstart, start>>16);
}
/*
* return the disk cluster for the iclust cluster in f
*/
long
fileclust(Xfile *f, long iclust, int cflag)
{
Dosbpb *bp;
Dosptr *dp;
Dosdir *d;
long start, clust, nskip, next;
bp = f->xf->ptr;
dp = f->ptr;
d = dp->d;
next = 0;
/*
* asking for the cluster of the root directory
* is not a well-formed question, since the root directory
* does not begin on a cluster boundary.
*/
if(!f->xf->isfat32 && isroot(dp->addr))
return -1;
if(f->xf->isfat32 && isroot(dp->addr)){
start = bp->rootstart;
}else{
start = getstart(f->xf, d);
if(start == 0){
if(!cflag)
return -1;
mlock(bp);
start = falloc(f->xf);
unmlock(bp);
if(start <= 0)
return -1;
puttime(d, 0);
putstart(f->xf, d, start);
dp->p->flags |= BMOD;
dp->clust = 0;
}
}
if(dp->clust == 0 || iclust < dp->iclust){
clust = start;
nskip = iclust;
}else{
clust = dp->clust;
nskip = iclust - dp->iclust;
}
if(chatty > 1 && nskip > 0)
chat("clust %#lx, skip %ld...", clust, nskip);
if(clust <= 0)
return -1;
if(nskip > 0){
mlock(bp);
while(--nskip >= 0){
next = getfat(f->xf, clust);
if(chatty > 1)
chat("->%#lx", next);
if(next > 0){
clust = next;
continue;
}else if(!cflag)
break;
if(d && (d->attr&DSYSTEM)){
next = cfalloc(f);
if(next < 0)
break;
/* cfalloc will call putfat for us, since clust may change */
} else {
next = falloc(f->xf);
if(next < 0)
break;
putfat(f->xf, clust, next);
}
clust = next;
}
unmlock(bp);
if(next <= 0)
return -1;
dp->clust = clust;
dp->iclust = iclust;
}
if(chatty > 1)
chat(" clust(%#lx)=%#lx...", iclust, clust);
return clust;
}
/*
* return the disk sector for the isect disk sector in f
*/
long
fileaddr(Xfile *f, long isect, int cflag)
{
Dosbpb *bp;
Dosptr *dp;
long clust;
bp = f->xf->ptr;
dp = f->ptr;
if(!f->xf->isfat32 && isroot(dp->addr)){
if(isect*bp->sectsize >= bp->rootsize*DOSDIRSIZE)
return -1;
return bp->rootaddr + isect;
}
clust = fileclust(f, isect/bp->clustsize, cflag);
if(clust < 0)
return -1;
return clust2sect(bp, clust) + isect%bp->clustsize;
}
/*
* translate names
*/
void
fixname(char *buf)
{
int c;
char *p;
p = buf;
while(c = *p){
if(c == ':' && trspaces)
*p = ' ';
p++;
}
}
/*
* classify the file name as one of
* Invalid - contains a bad character
* Short - short valid 8.3 name, no lowercase letters
* ShortLower - short valid 8.3 name except for lowercase letters
* Long - long name
*/
int
classifyname(char *buf)
{
char *p, *dot;
int c, isextended, is8dot3, islower, ndot;
p = buf;
isextended = 0;
islower = 0;
dot = nil;
ndot = 0;
while(c = (uchar)*p){
if(c&0x80) /* UTF8 */
isextended = 1;
else if(c == '.'){
dot = p;
ndot++;
}else if(strchr("+,:;=[] ", c))
isextended = 1;
else if(!isdos[c])
return Invalid;
if('a' <= c && c <= 'z')
islower = 1;
p++;
}
is8dot3 = (ndot==0 && p-buf <= 8) || (ndot==1 && dot-buf <= 8 && p-(dot+1) <= 3);
if(!isextended && is8dot3){
if(islower)
return ShortLower;
return Short;
}
return Long;
}
/*
* make an alias for a valid long file name
*/
void
mkalias(char *name, char *sname, int id)
{
Rune r;
char *s, *e, sid[10];
int i, esuf, v;
e = strrchr(name, '.');
if(e == nil)
e = strchr(name, '\0');
s = name;
i = 0;
while(s < e && i < 6){
if(isdos[(uchar)*s])
sname[i++] = *s++;
else
s += chartorune(&r, s);
}
v = snprint(sid, 10, "%d", id);
if(i + 1 + v > 8)
i = 8 - 1 - v;
sname[i++] = '~';
strcpy(&sname[i], sid);
i += v;
sname[i++] = '.';
esuf = i + 3;
if(esuf > 12)
panic("bad mkalias");
while(*e && i < esuf){
if(isdos[(uchar)*e])
sname[i++] = *e++;
else
e += chartorune(&r, e);
}
if(sname[i-1] == '.')
i--;
sname[i] = '\0';
}
/*
* check for valid plan 9 names,
* rewrite ' ' to ':'
*/
char isfrog[256]={
/*NUL*/ 1, 1, 1, 1, 1, 1, 1, 1,
/*BKS*/ 1, 1, 1, 1, 1, 1, 1, 1,
/*DLE*/ 1, 1, 1, 1, 1, 1, 1, 1,
/*CAN*/ 1, 1, 1, 1, 1, 1, 1, 1,
/* [' '] 1, let's try this -rsc */
['/'] 1,
[0x7f] 1,
};
int
nameok(char *elem)
{
while(*elem) {
if(*elem == ' ' && trspaces)
*elem = ':';
if(isfrog[*(uchar*)elem])
return 0;
elem++;
}
return 1;
}
/*
* look for a directory entry matching name
* always searches for long names which match a short name
*/
int
searchdir(Xfile *f, char *name, Dosptr *dp, int cflag, int longtype)
{
Xfs *xf;
Iosect *p;
Dosbpb *bp;
Dosdir *d;
char buf[261], *bname;
int isect, addr, o, addr1, addr2, prevaddr, prevaddr1, o1, islong, have, need, sum;
xf = f->xf;
bp = xf->ptr;
addr1 = -1;
addr2 = -1;
prevaddr1 = -1;
o1 = 0;
islong = 0;
sum = -1;
need = 1;
if(longtype!=Short && cflag)
need += (utflen(name) + DOSRUNE-1) / DOSRUNE;
memset(dp, 0, sizeof(Dosptr));
dp->prevaddr = -1;
dp->naddr = -1;
dp->paddr = ((Dosptr *)f->ptr)->addr;
dp->poffset = ((Dosptr *)f->ptr)->offset;
have = 0;
addr = -1;
bname = nil;
for(isect=0;; isect++){
prevaddr = addr;
addr = fileaddr(f, isect, cflag);
if(addr < 0)
break;
p = getsect(xf, addr);
if(p == 0)
break;
for(o=0; o<bp->sectsize; o+=DOSDIRSIZE){
d = (Dosdir *)&p->iobuf[o];
if(d->name[0] == 0x00){
chat("end dir(0)...");
putsect(p);
if(!cflag)
return -1;
/*
* addr1 & o1 are the start of the dirs
* addr2 is the optional second cluster used if the long name
* entry does not fit within the addr1 cluster
*
* have tells us the number of contiguous free dirs
* starting at addr1.o1; need are necessary to hold the long name.
*/
if(addr1 < 0){
addr1 = addr;
prevaddr1 = prevaddr;
o1 = o;
}
if(addr2 < 0 && (bp->sectsize-o)/DOSDIRSIZE + have < need){
addr2 = fileaddr(f, isect+1, cflag);
if(addr2 < 0)
goto breakout;
}else if(addr2 < 0)
addr2 = addr;
if(addr2 == addr1)
addr2 = -1;
dp->addr = addr1;
dp->offset = o1;
dp->prevaddr = prevaddr1;
dp->naddr = addr2;
return 0;
}
if(d->name[0] == DOSEMPTY){
if(chatty)
fprint(2, "empty dir\n");
have++;
if(addr1 == -1){
addr1 = addr;
o1 = o;
prevaddr1 = prevaddr;
}
if(addr2 == -1 && have >= need)
addr2 = addr;
continue;
}
have = 0;
if(addr2 == -1)
addr1 = -1;
dirdump(d);
if((d->attr & 0xf) == 0xf){
bname = getnamesect(buf, bname, p->iobuf + o, &islong, &sum, 1);
continue;
}
if(d->attr & DVLABEL){
islong = 0;
continue;
}
if(islong != 1 || sum != aliassum(d) || cistrcmp(bname, name) != 0){
bname = buf;
getname(buf, d);
}
islong = 0;
if(cistrcmp(bname, name) != 0)
continue;
if(chatty)
fprint(2, "found\n");
if(cflag){
putsect(p);
return -1;
}
dp->addr = addr;
dp->prevaddr = prevaddr;
dp->offset = o;
dp->p = p;
dp->d = d;
return 0;
}
putsect(p);
}
breakout:
chat("end dir(1)...");
return -1;
}
int
emptydir(Xfile *f)
{
Xfs *xf = f->xf;
Dosbpb *bp = xf->ptr;
int isect, addr, o;
Iosect *p;
Dosdir *d;
for(isect=0;; isect++){
addr = fileaddr(f, isect, 0);
if(addr < 0)
break;
p = getsect(xf, addr);
if(p == 0)
return -1;
for(o=0; o<bp->sectsize; o+=DOSDIRSIZE){
d = (Dosdir *)&p->iobuf[o];
if(d->name[0] == 0x00){
putsect(p);
return 0;
}
if(d->name[0] == DOSEMPTY)
continue;
if(d->name[0] == '.')
continue;
if(d->attr&DVLABEL)
continue;
putsect(p);
return -1;
}
putsect(p);
}
return 0;
}
long
readdir(Xfile *f, void *vbuf, long offset, long count)
{
Xfs *xf;
Dosbpb *bp;
Dir dir;
int isect, addr, o, islong, sum;
Iosect *p;
Dosdir *d;
long rcnt, n;
char *name, snamebuf[8+1+3+1], namebuf[DOSNAMELEN];
uchar *buf;
buf = vbuf;
rcnt = 0;
xf = f->xf;
bp = xf->ptr;
if(count <= 0)
return 0;
islong = 0;
sum = -1;
name = nil;
for(isect=0;; isect++){
addr = fileaddr(f, isect, 0);
if(addr < 0)
break;
p = getsect(xf, addr);
if(p == 0)
return -1;
for(o=0; o<bp->sectsize; o+=DOSDIRSIZE){
d = (Dosdir *)&p->iobuf[o];
if(d->name[0] == 0x00){
putsect(p);
return rcnt;
}
if(d->name[0] == DOSEMPTY)
continue;
dirdump(d);
if(d->name[0] == '.'){
if(d->name[1] == ' ' || d->name[1] == 0)
continue;
if(d->name[1] == '.' &&
(d->name[2] == ' ' || d->name[2] == 0))
continue;
}
if((d->attr & 0xf) == 0xf){
name = getnamesect(namebuf, name, p->iobuf+o, &islong, &sum, 1);
continue;
}
if(d->attr & DVLABEL){
islong = 0;
continue;
}
dir.name = snamebuf;
getdir(xf, &dir, d, addr, o);
if(islong == 1 && nameok(name) && sum == aliassum(d))
dir.name = name;
islong = 0;
n = convD2M(&dir, &buf[rcnt], count - rcnt);
name = nil;
if(n <= BIT16SZ){ /* no room for next entry */
putsect(p);
return rcnt;
}
rcnt += n;
if(offset > 0){
offset -= rcnt;
rcnt = 0;
islong = 0;
continue;
}
if(rcnt == count){
putsect(p);
return rcnt;
}
}
putsect(p);
}
return rcnt;
}
/*
* set up ndp for a directory's parent
* the hardest part is setting up paddr
*/
int
walkup(Xfile *f, Dosptr *ndp)
{
Dosbpb *bp;
Dosptr *dp;
Dosdir *xd;
Iosect *p;
long k, o, so, start, pstart, ppstart, st, ppclust;
bp = f->xf->ptr;
dp = f->ptr;
memset(ndp, 0, sizeof(Dosptr));
ndp->prevaddr = -1;
ndp->naddr = -1;
ndp->addr = dp->paddr;
ndp->offset = dp->poffset;
chat("walkup: paddr=%#lx...", dp->paddr);
/*
* root's paddr is always itself
*/
if(isroot(dp->paddr))
return 0;
/*
* find the start of our parent's directory
*/
p = getsect(f->xf, dp->paddr);
if(p == nil)
goto error;
xd = (Dosdir *)&p->iobuf[dp->poffset];
dirdump(xd);
start = getstart(f->xf, xd);
chat("start=%#lx...", start);
if(start == 0)
goto error;
putsect(p);
/*
* verify that parent's . points to itself
*/
p = getsect(f->xf, clust2sect(bp, start));
if(p == nil)
goto error;
xd = (Dosdir *)p->iobuf;
dirdump(xd);
st = getstart(f->xf, xd);
if(xd->name[0]!='.' || xd->name[1]!=' ' || start!=st)
goto error;
/*
* parent's .. is the next entry, and has start of parent's parent
*/
xd++;
dirdump(xd);
if(xd->name[0] != '.' || xd->name[1] != '.')
goto error;
pstart = getstart(f->xf, xd);
putsect(p);
/*
* we're done if parent is root
*/
if(pstart == 0 || f->xf->isfat32 && pstart == bp->rootstart)
return 0;
/*
* verify that parent's . points to itself
*/
p = getsect(f->xf, clust2sect(bp, pstart));
if(p == 0){
chat("getsect %ld failed\n", pstart);
goto error;
}
xd = (Dosdir *)p->iobuf;
dirdump(xd);
st = getstart(f->xf, xd);
if(xd->name[0]!='.' || xd->name[1]!=' ' || pstart!=st)
goto error;
/*
* parent's parent's .. is the next entry, and has start of parent's parent's parent
*/
xd++;
dirdump(xd);
if(xd->name[0] != '.' || xd->name[1] != '.')
goto error;
ppstart = getstart(f->xf, xd);
putsect(p);
/*
* open parent's parent's parent, and walk through it until parent's parent is found
* need this to find parent's parent's addr and offset
*/
ppclust = ppstart;
if(f->xf->isfat32 && ppclust == 0){
ppclust = bp->rootstart;
chat("ppclust 0, resetting to rootstart\n");
}
k = ppclust ? clust2sect(bp, ppclust) : bp->rootaddr;
p = getsect(f->xf, k);
if(p == nil){
chat("getsect %ld failed\n", k);
goto error;
}
xd = (Dosdir *)p->iobuf;
dirdump(xd);
if(ppstart){
st = getstart(f->xf, xd);
if(xd->name[0]!='.' || xd->name[1]!=' ' || ppstart!=st)
goto error;
}
for(so=1;; so++){
for(o=0; o<bp->sectsize; o+=DOSDIRSIZE){
xd = (Dosdir *)&p->iobuf[o];
if(xd->name[0] == 0x00){
chat("end dir\n");
goto error;
}
if(xd->name[0] == DOSEMPTY)
continue;
st = getstart(f->xf, xd);
if(st == pstart)
goto out;
}
if(ppclust){
if(so%bp->clustsize == 0){
mlock(bp);
ppclust = getfat(f->xf, ppclust);
unmlock(bp);
if(ppclust < 0){
chat("getfat %ld failed\n", ppclust);
goto error;
}
}
k = clust2sect(bp, ppclust) +
so%bp->clustsize;
}else{
if(so*bp->sectsize >= bp->rootsize*DOSDIRSIZE)
goto error;
k = bp->rootaddr + so;
}
putsect(p);
p = getsect(f->xf, k);
if(p == 0){
chat("getsect %ld failed\n", k);
goto error;
}
}
out:
putsect(p);
ndp->paddr = k;
ndp->poffset = o;
return 0;
error:
if(p)
putsect(p);
return -1;
}
long
readfile(Xfile *f, void *vbuf, long offset, long count)
{
Xfs *xf = f->xf;
Dosbpb *bp = xf->ptr;
Dosptr *dp = f->ptr;
Dosdir *d = dp->d;
int isect, addr, o, c;
Iosect *p;
uchar *buf;
long length, rcnt;
rcnt = 0;
length = GLONG(d->length);
buf = vbuf;
if(offset >= length)
return 0;
if(offset+count >= length)
count = length - offset;
isect = offset/bp->sectsize;
o = offset%bp->sectsize;
while(count > 0){
addr = fileaddr(f, isect++, 0);
if(addr < 0)
break;
c = bp->sectsize - o;
if(c > count)
c = count;
p = getsect(xf, addr);
if(p == 0)
return -1;
memmove(&buf[rcnt], &p->iobuf[o], c);
putsect(p);
count -= c;
rcnt += c;
o = 0;
}
return rcnt;
}
long
writefile(Xfile *f, void *vbuf, long offset, long count)
{
Xfs *xf = f->xf;
Dosbpb *bp = xf->ptr;
Dosptr *dp = f->ptr;
Dosdir *d = dp->d;
int isect, addr = 0, o, c;
Iosect *p;
uchar *buf;
long length, rcnt = 0, dlen;
buf = vbuf;
isect = offset/bp->sectsize;
o = offset%bp->sectsize;
while(count > 0){
addr = fileaddr(f, isect++, 1);
if(addr < 0)
break;
c = bp->sectsize - o;
if(c > count)
c = count;
if(c == bp->sectsize){
p = getosect(xf, addr);
p->flags = 0;
}else{
p = getsect(xf, addr);
if(p == nil)
return -1;
}
memmove(&p->iobuf[o], &buf[rcnt], c);
p->flags |= BMOD;
putsect(p);
count -= c;
rcnt += c;
o = 0;
}
if(rcnt <= 0 && addr < 0)
return -1;
length = 0;
dlen = GLONG(d->length);
if(rcnt > 0)
length = offset+rcnt;
else if(dp->addr && dp->clust){
c = bp->clustsize*bp->sectsize;
if(dp->iclust > (dlen+c-1)/c)
length = c*dp->iclust;
}
if(length > dlen)
PLONG(d->length, length);
puttime(d, 0);
dp->p->flags |= BMOD;
return rcnt;
}
int
truncfile(Xfile *f, long length)
{
Xfs *xf = f->xf;
Dosbpb *bp = xf->ptr;
Dosptr *dp = f->ptr;
Dosdir *d = dp->d;
long clust, next, n;
mlock(bp);
clust = getstart(f->xf, d);
n = length;
if(n <= 0)
putstart(f->xf, d, 0);
else
n -= bp->sectsize;
while(clust > 0){
next = getfat(xf, clust);
if(n <= 0)
putfat(xf, clust, 0);
else
n -= bp->clustsize*bp->sectsize;
clust = next;
}
unmlock(bp);
PLONG(d->length, length);
dp->iclust = 0;
dp->clust = 0;
dp->p->flags |= BMOD;
return 0;
}
void
putdir(Dosdir *d, Dir *dp)
{
if(dp->mode != ~0){
if(dp->mode & 2)
d->attr &= ~DRONLY;
else
d->attr |= DRONLY;
if(dp->mode & DMEXCL)
d->attr |= DSYSTEM;
else
d->attr &= ~DSYSTEM;
}
if(dp->mtime != ~0)
puttime(d, dp->mtime);
}
/*
* should extend this to deal with
* creation and access dates
*/
void
getdir(Xfs *xfs, Dir *dp, Dosdir *d, int addr, int offset)
{
if(d == nil || addr == 0)
panic("getdir on root");
dp->type = 0;
dp->dev = 0;
getname(dp->name, d);
dp->qid.path = addr*(Sectorsize/DOSDIRSIZE) +
offset/DOSDIRSIZE;
dp->qid.vers = 0;
if(d->attr & DRONLY)
dp->mode = 0444;
else
dp->mode = 0666;
dp->atime = gtime(d);
dp->mtime = dp->atime;
dp->qid.type = QTFILE;
if(d->attr & DDIR){
dp->qid.type = QTDIR;
dp->mode |= DMDIR|0111;
dp->length = 0;
}else
dp->length = GLONG(d->length);
if(d->attr & DSYSTEM){
dp->mode |= DMEXCL;
if(iscontig(xfs, d))
dp->mode |= DMAPPEND;
}
dp->uid = "bill";
dp->muid = "bill";
dp->gid = "trog";
}
void
getname(char *p, Dosdir *d)
{
int c, i;
for(i=0; i<8; i++){
c = d->name[i];
if(c == '\0' || c == ' ')
break;
if(i == 0 && c == 0x05)
c = 0xe5;
*p++ = c;
}
for(i=0; i<3; i++){
c = d->ext[i];
if(c == '\0' || c == ' ')
break;
if(i == 0)
*p++ = '.';
*p++ = c;
}
*p = 0;
}
static char*
getnamerunes(char *dst, uchar *buf, int step)
{
int i;
Rune r;
char dbuf[DOSRUNE * UTFmax + 1], *d;
d = dbuf;
r = 1;
for(i = 1; r && i < 11; i += 2){
r = buf[i] | (buf[i+1] << 8);
d += runetochar(d, &r);
}
for(i = 14; r && i < 26; i += 2){
r = buf[i] | (buf[i+1] << 8);
d += runetochar(d, &r);
}
for(i = 28; r && i < 32; i += 2){
r = buf[i] | (buf[i+1] << 8);
d += runetochar(d, &r);
}
if(step == 1)
dst -= d - dbuf;
memmove(dst, dbuf, d - dbuf);
if(step == -1){
dst += d - dbuf;
*dst = '\0';
}
return dst;
}
char*
getnamesect(char *dbuf, char *d, uchar *buf, int *islong, int *sum, int step)
{
/*
* validation checks to make sure we're
* making up a consistent name
*/
if(buf[11] != 0xf || buf[12] != 0){
*islong = 0;
return nil;
}
if(step == 1){
if((buf[0] & 0xc0) == 0x40){
*islong = buf[0] & 0x3f;
*sum = buf[13];
d = dbuf + DOSNAMELEN;
*--d = '\0';
}else if(*islong && *islong == buf[0] + 1 && *sum == buf[13]){
*islong = buf[0];
}else{
*islong = 0;
return nil;
}
}else{
if(*islong + 1 == (buf[0] & 0xbf) && *sum == buf[13]){
*islong = buf[0] & 0x3f;
if(buf[0] & 0x40)
*sum = -1;
}else{
*islong = 0;
*sum = -1;
return nil;
}
}
if(*islong > 20){
*islong = 0;
*sum = -1;
return nil;
}
return getnamerunes(d, buf, step);
}
void
putname(char *p, Dosdir *d)
{
int i;
memset(d->name, ' ', sizeof d->name+sizeof d->ext);
for(i=0; i<sizeof d->name; i++){
if(*p == 0 || *p == '.')
break;
d->name[i] = toupper(*p++);
}
p = strrchr(p, '.');
if(p){
for(i=0; i<sizeof d->ext; i++){
if(*++p == 0)
break;
d->ext[i] = toupper(*p);
}
}
}
static void
putnamesect(uchar *slot, Rune *longname, int curslot, int first, int sum)
{
Rune r;
Dosdir ds;
int i, j;
memset(&ds, 0xff, sizeof ds);
ds.attr = 0xf;
ds.reserved[0] = 0;
ds.reserved[1] = sum;
ds.start[0] = 0;
ds.start[1] = 0;
if(first)
ds.name[0] = 0x40 | curslot;
else
ds.name[0] = curslot;
memmove(slot, &ds, sizeof ds);
j = (curslot-1) * DOSRUNE;
for(i = 1; i < 11; i += 2){
r = longname[j++];
slot[i] = r;
slot[i+1] = r >> 8;
if(r == 0)
return;
}
for(i = 14; i < 26; i += 2){
r = longname[j++];
slot[i] = r;
slot[i+1] = r >> 8;
if(r == 0)
return;
}
for(i = 28; i < 32; i += 2){
r = longname[j++];
slot[i] = r;
slot[i+1] = r >> 8;
if(r == 0)
return;
}
}
int
aliassum(Dosdir *d)
{
int i, sum;
if(d == nil)
return -1;
sum = 0;
for(i = 0; i < 11; i++)
sum = (((sum&1)<<7) | ((sum&0xfe)>>1)) + d->name[i];
return sum & 0xff;
}
int
putlongname(Xfs *xf, Dosptr *ndp, char *name, char sname[13])
{
Dosbpb *bp;
Dosdir tmpd;
Rune longname[DOSNAMELEN+1];
int i, first, sum, nds, len;
/* calculate checksum */
putname(sname, &tmpd);
sum = aliassum(&tmpd);
bp = xf->ptr;
first = 1;
len = utftorunes(longname, name, DOSNAMELEN);
if(chatty){
chat("utftorunes %s =", name);
for(i=0; i<len; i++)
chat(" %.4X", longname[i]);
chat("\n");
}
for(nds = (len + DOSRUNE-1) / DOSRUNE; nds > 0; nds--){
putnamesect(&ndp->p->iobuf[ndp->offset], longname, nds, first, sum);
first = 0;
ndp->offset += 32;
if(ndp->offset == bp->sectsize){
chat("long name moving over sector boundary\n");
ndp->p->flags |= BMOD;
putsect(ndp->p);
ndp->p = nil;
/*
* switch to the next cluster for a long entry
* naddr should be set up correctly by searchdir
*/
ndp->prevaddr = ndp->addr;
ndp->addr = ndp->naddr;
ndp->naddr = -1;
if(ndp->addr == -1)
return -1;
ndp->p = getsect(xf, ndp->addr);
if(ndp->p == nil)
return -1;
ndp->offset = 0;
ndp->d = (Dosdir *)&ndp->p->iobuf[ndp->offset];
}
}
return 0;
}
long
getfat(Xfs *xf, int n)
{
Dosbpb *bp = xf->ptr;
Iosect *p;
ulong k, sect;
int o, fb;
if(n < FATRESRV || n >= bp->fatclusters)
return -1;
fb = bp->fatbits;
k = (fb * n) >> 3;
if(k >= bp->fatsize*bp->sectsize)
panic("getfat");
sect = k/bp->sectsize + bp->fataddr;
o = k%bp->sectsize;
p = getsect(xf, sect);
if(p == nil)
return -1;
k = p->iobuf[o++];
if(o >= bp->sectsize){
putsect(p);
p = getsect(xf, sect+1);
if(p == nil)
return -1;
o = 0;
}
k |= p->iobuf[o++]<<8;
if(fb == 32){
/* fat32 is really fat28 */
k |= p->iobuf[o++] << 16;
k |= (p->iobuf[o] & 0x0f) << 24;
fb = 28;
}
putsect(p);
if(fb == 12){
if(n&1)
k >>= 4;
else
k &= 0xfff;
}
if(chatty > 1)
chat("fat(%#x)=%#lx...", n, k);
/*
* This is a very strange check for out of range.
* As a concrete example, for a 16-bit FAT,
* FFF8 through FFFF all signify ``end of cluster chain.''
* This generalizes to other-sized FATs.
*/
if(k >= (1 << fb) - 8)
return -1;
return k;
}
void
putfat(Xfs *xf, int n, ulong val)
{
Fatinfo *fi;
Dosbpb *bp;
Iosect *p;
ulong k, sect, esect;
int o;
bp = xf->ptr;
if(n < FATRESRV || n >= bp->fatclusters)
panic("putfat n=%d", n);
k = (bp->fatbits * n) >> 3;
if(k >= bp->fatsize*bp->sectsize)
panic("putfat");
sect = k/bp->sectsize + bp->fataddr;
esect = sect + bp->nfats * bp->fatsize;
for(; sect<esect; sect+=bp->fatsize){
o = k%bp->sectsize;
p = getsect(xf, sect);
if(p == nil)
continue;
switch(bp->fatbits){
case 12:
if(n&1){
p->iobuf[o] &= 0x0f;
p->iobuf[o++] |= val<<4;
if(o >= bp->sectsize){
p->flags |= BMOD;
putsect(p);
p = getsect(xf, sect+1);
if(p == nil)
continue;
o = 0;
}
p->iobuf[o] = val>>4;
}else{
p->iobuf[o++] = val;
if(o >= bp->sectsize){
p->flags |= BMOD;
putsect(p);
p = getsect(xf, sect+1);
if(p == nil)
continue;
o = 0;
}
p->iobuf[o] &= 0xf0;
p->iobuf[o] |= (val>>8) & 0x0f;
}
break;
case 16:
p->iobuf[o++] = val;
p->iobuf[o] = val>>8;
break;
case 32: /* fat32 is really fat28 */
p->iobuf[o++] = val;
p->iobuf[o++] = val>>8;
p->iobuf[o++] = val>>16;
p->iobuf[o] = (p->iobuf[o] & 0xf0) | ((val>>24) & 0x0f);
break;
default:
panic("putfat fatbits");
}
p->flags |= BMOD;
putsect(p);
}
if(val == 0)
bp->freeclusters++;
else
bp->freeclusters--;
if(bp->fatinfo){
p = getsect(xf, bp->fatinfo);
if(p != nil){
fi = (Fatinfo*)p->iobuf;
PLONG(fi->nextfree, bp->freeptr);
PLONG(fi->freeclust, bp->freeclusters);
p->flags |= BMOD;
putsect(p);
}
}
}
/*
* Contiguous falloc; if we can, use lastclust+1.
* Otherwise, move the file to get some space.
* If there just isn't enough contiguous space
* anywhere on disk, fail.
*/
int
cfalloc(Xfile *f)
{
int l;
if((l=makecontig(f, 8)) >= 0)
return l;
return makecontig(f, 1);
}
/*
* Check whether a file is contiguous.
*/
int
iscontig(Xfs *xf, Dosdir *d)
{
long clust, next;
clust = getstart(xf, d);
if(clust <= 0)
return 1;
for(;;) {
next = getfat(xf, clust);
if(next < 0)
return 1;
if(next != clust+1)
return 0;
clust = next;
}
return 0; /* not reached */
}
/*
* Make a file contiguous, with nextra clusters of
* free space after it for later expansion.
* Return the number of the first new cluster.
*/
int
makecontig(Xfile *f, int nextra)
{
Dosbpb *bp;
Dosdir *d;
Dosptr *dp;
Xfs *xf;
Iosect *wp, *rp;
long clust, next, last, start, rclust, wclust, eclust, ostart;
int isok, i, n, nclust, nrun, rs, ws;
xf = f->xf;
bp = xf->ptr;
dp = f->ptr;
d = dp->d;
isok = 1;
nclust = 0;
clust = fileclust(f, 0, 0);
chat("clust %#lux", clust);
if(clust != -1) {
for(;;) {
nclust++;
chat(".");
next = getfat(xf, clust);
if(next <= 0)
break;
if(next != clust+1)
isok = 0;
clust = next;
}
}
chat("nclust %d\n", nclust);
if(isok && clust != -1) {
eclust = clust+1; /* eclust = first cluster past file */
assert(eclust == fileclust(f, 0, 0)+nclust);
for(i=0; i<nextra; i++)
if(getfat(xf, eclust+i) != 0)
break;
if(i == nextra) { /* they were all free */
chat("eclust=%#lx, getfat eclust-1 = %#lux\n", eclust, getfat(xf, eclust-1));
assert(getfat(xf, eclust-1) == 0xffffffff);
putfat(xf, eclust-1, eclust);
putfat(xf, eclust, 0xffffffff);
bp->freeptr = clust+1; /* to help keep the blocks free */
return eclust;
}
}
/* need to search for nclust+nextra contiguous free blocks */
last = -1;
n = bp->freeptr;
nrun = 0;
for(;;){
if(getfat(xf, n) == 0) {
if(last+1 == n)
nrun++;
else
nrun = 1;
if(nrun >= nclust+nextra)
break;
last = n;
}
if(++n >= bp->fatclusters)
n = FATRESRV;
if(n == bp->freeptr) {
errno = Econtig;
return -1;
}
}
bp->freeptr = n+1;
/* copy old data over */
start = n+1 - nrun;
/* sanity check */
for(i=0; i<nclust+nextra; i++)
assert(getfat(xf, start+i) == 0);
chat("relocate chain %lux -> 0x%lux len %d\n", fileclust(f, 0, 0), start, nclust);
wclust = start;
for(rclust = fileclust(f, 0, 0); rclust > 0; rclust = next){
rs = clust2sect(bp, rclust);
ws = clust2sect(bp, wclust);
for(i=0; i<bp->clustsize; i++, rs++, ws++){
rp = getsect(xf, rs);
if(rp == nil)
return -1;
wp = getosect(xf, ws);
assert(wp != nil);
memmove(wp->iobuf, rp->iobuf, bp->sectsize);
wp->flags = BMOD;
putsect(rp);
putsect(wp);
}
chat("move cluster %#lx -> %#lx...", rclust, wclust);
next = getfat(xf, rclust);
putfat(xf, wclust, wclust+1);
wclust++;
}
/* now wclust points at the first new cluster; chain it in */
chat("wclust 0x%lux start 0x%lux (fat->0x%lux) nclust %d\n", wclust, start, getfat(xf, start), nclust);
assert(wclust == start+nclust);
putfat(xf, wclust, 0xffffffff); /* end of file */
/* update directory entry to point at new start */
ostart = fileclust(f, 0, 0);
putstart(xf, d, start);
/* check our work */
i = 0;
clust = fileclust(f, 0, 0);
if(clust != -1) {
for(;;) {
i++;
next = getfat(xf, clust);
if(next <= 0)
break;
assert(next == clust+1);
clust = next;
}
}
chat("chain check: len %d\n", i);
assert(i == nclust+1);
/* succeeded; remove old chain. */
for(rclust = ostart; rclust > 0; rclust = next){
next = getfat(xf, rclust);
putfat(xf, rclust, 0); /* free cluster */
}
return start+nclust;
}
int
falloc(Xfs *xf)
{
Dosbpb *bp = xf->ptr;
Iosect *p;
int n, i, k;
n = bp->freeptr;
for(;;){
if(getfat(xf, n) == 0)
break;
if(++n >= bp->fatclusters)
n = FATRESRV;
if(n == bp->freeptr)
return -1;
}
bp->freeptr = n+1;
if(bp->freeptr >= bp->fatclusters)
bp->freeptr = FATRESRV;
putfat(xf, n, 0xffffffff);
k = clust2sect(bp, n);
for(i=0; i<bp->clustsize; i++){
p = getosect(xf, k+i);
memset(p->iobuf, 0, bp->sectsize);
p->flags = BMOD;
putsect(p);
}
return n;
}
void
ffree(Xfs *xf, long start)
{
putfat(xf, start, 0);
}
long
clust2sect(Dosbpb *bp, long clust)
{
return bp->dataaddr + (clust - FATRESRV) * bp->clustsize;
}
long
sect2clust(Dosbpb *bp, long sect)
{
long c;
c = (sect - bp->dataaddr) / bp->clustsize + FATRESRV;
assert(sect == clust2sect(bp, c));
return c;
}
void
puttime(Dosdir *d, long s)
{
Tm *t;
ushort x;
if(s == 0)
s = time(0);
t = localtime(s);
x = (t->hour<<11) | (t->min<<5) | (t->sec>>1);
PSHORT(d->time, x);
x = ((t->year-80)<<9) | ((t->mon+1)<<5) | t->mday;
PSHORT(d->date, x);
}
long
gtime(Dosdir *dp)
{
Tm tm;
int i;
i = GSHORT(dp->time);
tm.hour = i >> 11;
tm.min = (i >> 5) & 63;
tm.sec = (i & 31) << 1;
i = GSHORT(dp->date);
tm.year = 80 + (i >> 9);
tm.mon = ((i >> 5) & 15) - 1;
tm.mday = i & 31;
tm.zone[0] = '\0';
tm.tzoff = 0;
return tm2sec(&tm);
}
/*
* structure dumps for debugging
*/
void
bootdump(int fd, Dosboot *b)
{
Biobuf bp;
Binit(&bp, fd, OWRITE);
Bprint(&bp, "magic: 0x%2.2x 0x%2.2x 0x%2.2x\n",
b->magic[0], b->magic[1], b->magic[2]);
Bprint(&bp, "version: \"%8.8s\"\n", (char*)b->version);
Bprint(&bp, "sectsize: %d\n", GSHORT(b->sectsize));
Bprint(&bp, "clustsize: %d\n", b->clustsize);
Bprint(&bp, "nresrv: %d\n", GSHORT(b->nresrv));
Bprint(&bp, "nfats: %d\n", b->nfats);
Bprint(&bp, "rootsize: %d\n", GSHORT(b->rootsize));
Bprint(&bp, "volsize: %d\n", GSHORT(b->volsize));
Bprint(&bp, "mediadesc: 0x%2.2x\n", b->mediadesc);
Bprint(&bp, "fatsize: %d\n", GSHORT(b->fatsize));
Bprint(&bp, "trksize: %d\n", GSHORT(b->trksize));
Bprint(&bp, "nheads: %d\n", GSHORT(b->nheads));
Bprint(&bp, "nhidden: %ld\n", GLONG(b->nhidden));
Bprint(&bp, "bigvolsize: %ld\n", GLONG(b->bigvolsize));
Bprint(&bp, "driveno: %d\n", b->driveno);
Bprint(&bp, "reserved0: 0x%2.2x\n", b->reserved0);
Bprint(&bp, "bootsig: 0x%2.2x\n", b->bootsig);
Bprint(&bp, "volid: 0x%8.8lux\n", GLONG(b->volid));
Bprint(&bp, "label: \"%11.11s\"\n", (char*)b->label);
Bterm(&bp);
}
void
bootdump32(int fd, Dosboot32 *b)
{
Biobuf bp;
Binit(&bp, fd, OWRITE);
Bprint(&bp, "magic: 0x%2.2x 0x%2.2x 0x%2.2x\n",
b->magic[0], b->magic[1], b->magic[2]);
Bprint(&bp, "version: \"%8.8s\"\n", (char*)b->version);
Bprint(&bp, "sectsize: %d\n", GSHORT(b->sectsize));
Bprint(&bp, "clustsize: %d\n", b->clustsize);
Bprint(&bp, "nresrv: %d\n", GSHORT(b->nresrv));
Bprint(&bp, "nfats: %d\n", b->nfats);
Bprint(&bp, "rootsize: %d\n", GSHORT(b->rootsize));
Bprint(&bp, "volsize: %d\n", GSHORT(b->volsize));
Bprint(&bp, "mediadesc: 0x%2.2x\n", b->mediadesc);
Bprint(&bp, "fatsize: %d\n", GSHORT(b->fatsize));
Bprint(&bp, "trksize: %d\n", GSHORT(b->trksize));
Bprint(&bp, "nheads: %d\n", GSHORT(b->nheads));
Bprint(&bp, "nhidden: %ld\n", GLONG(b->nhidden));
Bprint(&bp, "bigvolsize: %ld\n", GLONG(b->bigvolsize));
Bprint(&bp, "fatsize32: %ld\n", GLONG(b->fatsize32));
Bprint(&bp, "extflags: %d\n", GSHORT(b->extflags));
Bprint(&bp, "version: %d\n", GSHORT(b->version1));
Bprint(&bp, "rootstart: %ld\n", GLONG(b->rootstart));
Bprint(&bp, "infospec: %d\n", GSHORT(b->infospec));
Bprint(&bp, "backupboot: %d\n", GSHORT(b->backupboot));
Bprint(&bp, "reserved: %d %d %d %d %d %d %d %d %d %d %d %d\n",
b->reserved[0], b->reserved[1], b->reserved[2], b->reserved[3],
b->reserved[4], b->reserved[5], b->reserved[6], b->reserved[7],
b->reserved[8], b->reserved[9], b->reserved[10], b->reserved[11]);
Bterm(&bp);
}
void
bootsecdump32(int fd, Xfs *xf, Dosboot32 *b32)
{
Fatinfo *fi;
Iosect *p1;
int fisec, bsec, res;
fprint(fd, "\nfat32\n");
bootdump32(fd, b32);
res = GSHORT(b32->nresrv);
bsec = GSHORT(b32->backupboot);
if(bsec < res && bsec != 0){
p1 = getsect(xf, bsec);
if(p1 == nil)
fprint(fd, "\ncouldn't get backup boot sector: %r\n");
else{
fprint(fd, "\nbackup boot\n");
bootdump32(fd, (Dosboot32*)p1->iobuf);
putsect(p1);
}
}else if(bsec != 0xffff)
fprint(fd, "bad backup boot sector: %d reserved %d\n", bsec, res);
fisec = GSHORT(b32->infospec);
if(fisec < res && fisec != 0){
p1 = getsect(xf, fisec);
if(p1 == nil)
fprint(fd, "\ncouldn't get fat info sector: %r\n");
else{
fprint(fd, "\nfat info %d\n", fisec);
fi = (Fatinfo*)p1->iobuf;
fprint(fd, "sig1: 0x%lux sb 0x%lux\n", GLONG(fi->sig1), FATINFOSIG1);
fprint(fd, "sig: 0x%lux sb 0x%lux\n", GLONG(fi->sig), FATINFOSIG);
fprint(fd, "freeclust: %lud\n", GLONG(fi->freeclust));
fprint(fd, "nextfree: %lud\n", GLONG(fi->nextfree));
fprint(fd, "reserved: %lud %lud %lud\n", GLONG(fi->resrv), GLONG(fi->resrv+4), GLONG(fi->resrv+8));
putsect(p1);
}
}else if(fisec != 0xffff)
fprint(2, "bad fat info sector: %d reserved %d\n", bsec, res);
}
void
dirdump(void *vdbuf)
{
static char attrchar[] = "rhsvda67";
Dosdir *d;
char *name, namebuf[DOSNAMELEN];
char buf[128], *s, *ebuf;
uchar *dbuf;
int i;
if(!chatty)
return;
d = vdbuf;
ebuf = buf + sizeof(buf);
if(d->attr == 0xf){
dbuf = vdbuf;
name = namebuf + DOSNAMELEN;
*--name = '\0';
name = getnamerunes(name, dbuf, 1);
seprint(buf, ebuf, "\"%s\" %2.2x %2.2ux %2.2ux %d", name, dbuf[0], dbuf[12], dbuf[13], GSHORT(d->start));
}else{
s = seprint(buf, ebuf, "\"%.8s.%.3s\" ", (char*)d->name, (char*)d->ext);
for(i=7; i>=0; i--)
*s++ = d->attr&(1<<i) ? attrchar[i] : '-';
i = GSHORT(d->time);
s = seprint(s, ebuf, " %2.2d:%2.2d:%2.2d", i>>11, (i>>5)&63, (i&31)<<1);
i = GSHORT(d->date);
s = seprint(s, ebuf, " %2.2d.%2.2d.%2.2d", 80+(i>>9), (i>>5)&15, i&31);
i = GSHORT(d->ctime);
s = seprint(s, ebuf, " %2.2d:%2.2d:%2.2d", i>>11, (i>>5)&63, (i&31)<<1);
i = GSHORT(d->cdate);
s = seprint(s, ebuf, " %2.2d.%2.2d.%2.2d", 80+(i>>9), (i>>5)&15, i&31);
i = GSHORT(d->adate);
s = seprint(s, ebuf, " %2.2d.%2.2d.%2.2d", 80+(i>>9), (i>>5)&15, i&31);
seprint(s, ebuf, " %d %d", GSHORT(d->start), GSHORT(d->length));
}
chat("%s\n", buf);
}
int
cistrcmp(char *s1, char *s2)
{
int c1, c2;
while(*s1){
c1 = *s1++;
c2 = *s2++;
if(c1 >= 'A' && c1 <= 'Z')
c1 -= 'A' - 'a';
if(c2 >= 'A' && c2 <= 'Z')
c2 -= 'A' - 'a';
if(c1 != c2)
return c1 - c2;
}
return -*s2;
}
int
utftorunes(Rune *rr, char *s, int n)
{
Rune *r, *re;
int c;
r = rr;
re = r + n - 1;
while(c = (uchar)*s){
if(c < Runeself){
*r = c;
s++;
}else
s += chartorune(r, s);
r++;
if(r >= re)
break;
}
*r = 0;
return r - rr;
}
