ref: a8d00e5d56b261376410c3c87c46327362763bd8
dir: /sys/src/cmd/dossrv/dosfs.c/
#include <u.h> #include <libc.h> #include <auth.h> #include <fcall.h> #include "iotrack.h" #include "dat.h" #include "dosfs.h" #include "fns.h" void rversion(void) { if(req->msize > Maxiosize) rep->msize = Maxiosize; else rep->msize = req->msize; rep->version = "9P2000"; } void rauth(void) { errno = Enoauth; } void rflush(void) { } void rattach(void) { Xfs *xf; Xfile *root; Dosptr *dp; root = xfile(req->fid, Clean); if(!root){ errno = Enomem; goto error; } root->xf = xf = getxfs(req->uname, req->aname); if(!xf) goto error; if(xf->fmt == 0 && dosfs(xf) < 0){ errno = Eformat; goto error; } root->qid.type = QTDIR; root->qid.path = 0; root->qid.vers = 0; root->xf->rootqid = root->qid; dp = malloc(sizeof(Dosptr)); if(dp == nil){ errno = Enomem; goto error; } root->ptr = dp; rootfile(root); rep->qid = root->qid; return; error: if(root) xfile(req->fid, Clunk); } Xfile* doclone(Xfile *of, int newfid) { Xfile *nf, *next; Dosptr *dp; nf = xfile(newfid, Clean); if(!nf){ errno = Enomem; return nil; } dp = malloc(sizeof(Dosptr)); if(dp == nil){ errno = Enomem; return nil; } next = nf->next; *nf = *of; nf->next = next; nf->fid = req->newfid; nf->ptr = dp; refxfs(nf->xf, 1); memmove(dp, of->ptr, sizeof(Dosptr)); dp->p = nil; dp->d = nil; return nf; } void rwalk(void) { Xfile *f, *nf; Dosptr dp[1], savedp[1]; int r, longtype; Qid saveqid; rep->nwqid = 0; nf = nil; f = xfile(req->fid, Asis); if(f == nil){ chat("\tno xfile\n"); goto error2; } if(req->fid != req->newfid){ nf = doclone(f, req->newfid); if(nf == nil){ chat("\tclone failed\n"); goto error2; } f = nf; } saveqid = f->qid; memmove(savedp, f->ptr, sizeof(Dosptr)); for(; rep->nwqid < req->nwname && rep->nwqid < MAXWELEM; rep->nwqid++){ chat("\twalking %s\n", req->wname[rep->nwqid]); if(!(f->qid.type & QTDIR)){ chat("\tnot dir: type=%#x\n", f->qid.type); goto error; } if(strcmp(req->wname[rep->nwqid], ".") == 0){ ; }else if(strcmp(req->wname[rep->nwqid], "..") == 0){ if(f->qid.path != f->xf->rootqid.path){ r = walkup(f, dp); if(r < 0) goto error; memmove(f->ptr, dp, sizeof(Dosptr)); if(isroot(dp->addr)) f->qid.path = f->xf->rootqid.path; else f->qid.path = QIDPATH(dp); } }else{ fixname(req->wname[rep->nwqid]); longtype = classifyname(req->wname[rep->nwqid]); if(longtype==Invalid || getfile(f) < 0) goto error; /* * always do a search for the long name, * because it could be filed as such */ r = searchdir(f, req->wname[rep->nwqid], dp, 0, longtype); putfile(f); if(r < 0) goto error; memmove(f->ptr, dp, sizeof(Dosptr)); f->qid.path = QIDPATH(dp); f->qid.type = QTFILE; if(isroot(dp->addr)) f->qid.path = f->xf->rootqid.path; else if(dp->d->attr & DDIR) f->qid.type = QTDIR; else if(dp->d->attr & DSYSTEM){ f->qid.type |= QTEXCL; if(iscontig(f->xf, dp->d)) f->qid.type |= QTAPPEND; } //ZZZ maybe use other bits than qtexcl & qtapppend putfile(f); } rep->wqid[rep->nwqid] = f->qid; } return; error: f->qid = saveqid; memmove(f->ptr, savedp, sizeof(Dosptr)); if(nf != nil) xfile(req->newfid, Clunk); error2: if(!errno && !rep->nwqid) errno = Enonexist; } void ropen(void) { Xfile *f; Iosect *p; Dosptr *dp; int attr, omode; f = xfile(req->fid, Asis); if(!f || (f->flags&Omodes)){ errno = Eio; return; } dp = f->ptr; omode = 0; if(!isroot(dp->paddr) && (req->mode & ORCLOSE)){ /* * check on parent directory of file to be deleted */ p = getsect(f->xf, dp->paddr); if(p == nil){ errno = Eio; return; } attr = ((Dosdir *)&p->iobuf[dp->poffset])->attr; putsect(p); if(attr & DRONLY){ errno = Eperm; return; } omode |= Orclose; }else if(req->mode & ORCLOSE) omode |= Orclose; if(getfile(f) < 0){ errno = Enonexist; return; } if(!isroot(dp->addr)) attr = dp->d->attr; else attr = DDIR; switch(req->mode & 7){ case OREAD: case OEXEC: omode |= Oread; break; case ORDWR: omode |= Oread; /* fall through */ case OWRITE: omode |= Owrite; if(attr & DRONLY){ errno = Eperm; goto out; } break; default: errno = Eio; goto out; } if(req->mode & OTRUNC){ if(attr & DDIR || attr & DRONLY){ errno = Eperm; goto out; } if(truncfile(f, 0) < 0){ errno = Eio; goto out; } } f->flags |= omode; rep->qid = f->qid; rep->iounit = 0; out: putfile(f); } static int mk8dot3name(Xfile *f, Dosptr *ndp, char *name, char *sname) { Dosptr tmpdp; int i, longtype; if(strcmp(name, ".") == 0 || strcmp(name, "..") == 0) return Invalid; /* * always do a search for the long name, * because it could be filed as such */ fixname(name); longtype = classifyname(name); if(longtype==Invalid || searchdir(f, name, ndp, 1, longtype) < 0) return Invalid; if(longtype==Short) return Short; if(longtype==ShortLower){ /* * alias is the upper-case version, which we * already know does not exist. */ strcpy(sname, name); for(i=0; sname[i]; i++) if('a' <= sname[i] && sname[i] <= 'z') sname[i] += 'A'-'a'; return ShortLower; } /* * find alias for the long name */ for(i=1;; i++){ mkalias(name, sname, i); if(searchdir(f, sname, &tmpdp, 0, 0) < 0) return Long; putsect(tmpdp.p); } } /* * fill in a directory entry for a new file */ static int mkdentry(Xfs *xf, Dosptr *ndp, char *name, char *sname, int longtype, int nattr, long start, ulong length) { Dosdir *nd; /* * fill in the entry */ ndp->p = getsect(xf, ndp->addr); if(ndp->p == nil || longtype!=Short && putlongname(xf, ndp, name, sname) < 0){ errno = Eio; return -1; } ndp->d = (Dosdir *)&ndp->p->iobuf[ndp->offset]; nd = ndp->d; memset(nd, 0, DOSDIRSIZE); if(longtype!=Short) name = sname; putname(name, nd); nd->attr = nattr; puttime(nd, 0); PSHORT(nd->cdate, GSHORT(nd->date)); PSHORT(nd->ctime, GSHORT(nd->time)); nd->ctimetenth = 0; putstart(xf, nd, start); PLONG(nd->length, length); ndp->p->flags |= BMOD; return 0; } void rcreate(void) { Dosbpb *bp; Xfile *f; Dosptr *pdp, *ndp; Iosect *xp; Dosdir *pd, *xd; char sname[13]; long start; int longtype, attr, omode, nattr; f = xfile(req->fid, Asis); if(!f || (f->flags&Omodes) || getfile(f)<0){ errno = Eio; return; } pdp = f->ptr; pd = pdp->d; /* * perm check */ if(isroot(pdp->addr) && pd != nil) panic("root pd != nil"); attr = pd ? pd->attr : DDIR; if(!(attr & DDIR) || (attr & DRONLY)){ badperm: putfile(f); errno = Eperm; return; } omode = 0; if(req->mode & ORCLOSE) omode |= Orclose; switch(req->mode & 7){ case OREAD: case OEXEC: omode |= Oread; break; case ORDWR: omode |= Oread; /* fall through */ case OWRITE: omode |= Owrite; if(req->perm & DMDIR) goto badperm; break; default: goto badperm; } /* * check the name, find the slot for the dentry, * and find a good alias for a long name */ ndp = malloc(sizeof(Dosptr)); if(ndp == nil){ putfile(f); errno = Enomem; return; } longtype = mk8dot3name(f, ndp, req->name, sname); chat("rcreate %s longtype %d...\n", req->name, longtype); if(longtype == Invalid){ free(ndp); goto badperm; } /* * allocate first cluster, if making directory */ start = 0; bp = nil; if(req->perm & DMDIR){ bp = f->xf->ptr; mlock(bp); start = falloc(f->xf); unmlock(bp); if(start <= 0){ free(ndp); putfile(f); errno = Eio; return; } } /* * make the entry */ nattr = 0; if((req->perm & 0222) == 0) nattr |= DRONLY; if(req->perm & DMDIR) nattr |= DDIR; if(mkdentry(f->xf, ndp, req->name, sname, longtype, nattr, start, 0) < 0){ if(ndp->p != nil) putsect(ndp->p); free(ndp); if(start > 0) ffree(f->xf, start); putfile(f); return; } if(pd != nil){ puttime(pd, 0); pdp->p->flags |= BMOD; } /* * fix up the fid */ f->ptr = ndp; f->qid.type = QTFILE; f->qid.path = QIDPATH(ndp); //ZZZ set type for excl, append? if(req->perm & DMDIR){ f->qid.type = QTDIR; xp = getsect(f->xf, clust2sect(bp, start)); if(xp == nil){ errno = Eio; goto badio; } xd = (Dosdir *)&xp->iobuf[0]; memmove(xd, ndp->d, DOSDIRSIZE); memset(xd->name, ' ', sizeof xd->name+sizeof xd->ext); xd->name[0] = '.'; xd = (Dosdir *)&xp->iobuf[DOSDIRSIZE]; if(pd) memmove(xd, pd, DOSDIRSIZE); else{ memset(xd, 0, DOSDIRSIZE); puttime(xd, 0); xd->attr = DDIR; } memset(xd->name, ' ', sizeof xd->name+sizeof xd->ext); xd->name[0] = '.'; xd->name[1] = '.'; xp->flags |= BMOD; putsect(xp); } f->flags |= omode; rep->qid = f->qid; rep->iounit = 0; badio: putfile(f); putsect(pdp->p); free(pdp); } void rread(void) { Xfile *f; int r; if (!(f=xfile(req->fid, Asis)) || !(f->flags&Oread)) goto error; if(req->count > sizeof repdata) req->count = sizeof repdata; if(getfile(f) < 0) goto error; if(f->qid.type & QTDIR) r = readdir(f, repdata, req->offset, req->count); else r = readfile(f, repdata, req->offset, req->count); putfile(f); if(r < 0){ error: errno = Eio; }else{ rep->count = r; rep->data = (char*)repdata; } } void rwrite(void) { Xfile *f; int r; if (!(f=xfile(req->fid, Asis)) || !(f->flags&Owrite)) goto error; if(getfile(f) < 0) goto error; r = writefile(f, req->data, req->offset, req->count); putfile(f); if(r < 0){ error: errno = Eio; }else{ rep->count = r; } } void rclunk(void) { xfile(req->fid, Clunk); sync(); } /* * wipe out a dos directory entry */ static void doremove(Xfs *xf, Dosptr *dp) { Iosect *p; int prevdo; dp->p->iobuf[dp->offset] = DOSEMPTY; dp->p->flags |= BMOD; for(prevdo = dp->offset-DOSDIRSIZE; prevdo >= 0; prevdo -= DOSDIRSIZE){ if(dp->p->iobuf[prevdo+11] != 0xf) break; dp->p->iobuf[prevdo] = DOSEMPTY; } if(prevdo < 0 && dp->prevaddr != -1){ p = getsect(xf, dp->prevaddr); for(prevdo = ((Dosbpb*)xf->ptr)->sectsize-DOSDIRSIZE; prevdo >= 0; prevdo -= DOSDIRSIZE){ if(p->iobuf[prevdo+11] != 0xf) break; p->iobuf[prevdo] = DOSEMPTY; p->flags |= BMOD; } putsect(p); } } void rremove(void) { Xfile *f; Dosptr *dp; Iosect *parp; Dosdir *pard; f = xfile(req->fid, Asis); parp = nil; if(f == nil){ errno = Eio; goto out; } dp = f->ptr; if(isroot(dp->addr)){ errno = Eperm; goto out; } /* * can't remove if parent is read only, * it's a non-empty directory, * or it's a read only file in the root directory */ parp = getsect(f->xf, dp->paddr); if(parp == nil || getfile(f) < 0){ errno = Eio; goto out; } pard = (Dosdir *)&parp->iobuf[dp->poffset]; if(!isroot(dp->paddr) && (pard->attr & DRONLY) || (dp->d->attr & DDIR) && emptydir(f) < 0 || isroot(dp->paddr) && (dp->d->attr&DRONLY)){ errno = Eperm; goto out; } if(truncfile(f, 0) < 0){ errno = Eio; goto out; } doremove(f->xf, f->ptr); if(!isroot(dp->paddr)){ puttime(pard, 0); parp->flags |= BMOD; } out: if(parp != nil) putsect(parp); if(f != nil) putfile(f); xfile(req->fid, Clunk); sync(); } static void dostat(Xfile *f, Dir *d) { Dosptr *dp; Iosect *p; char *name, namebuf[DOSNAMELEN]; int islong, sum, prevdo; dp = f->ptr; if(isroot(dp->addr)){ memset(d, 0, sizeof(Dir)); d->name = "/"; d->qid.type = QTDIR; d->qid.path = f->xf->rootqid.path; d->mode = DMDIR|0777; d->uid = "bill"; d->muid = "bill"; d->gid = "trog"; }else{ /* * assemble any long file name */ sum = aliassum(dp->d); islong = 0; name = namebuf; for(prevdo = dp->offset-DOSDIRSIZE; prevdo >= 0; prevdo -= DOSDIRSIZE){ if(dp->p->iobuf[prevdo+11] != 0xf) break; name = getnamesect(namebuf, name, &dp->p->iobuf[prevdo], &islong, &sum, -1); } if(prevdo < 0 && dp->prevaddr != -1){ p = getsect(f->xf, dp->prevaddr); for(prevdo = ((Dosbpb*)f->xf->ptr)->sectsize-DOSDIRSIZE; prevdo >= 0; prevdo -= DOSDIRSIZE){ if(p->iobuf[prevdo+11] != 0xf) break; name = getnamesect(namebuf, name, &p->iobuf[prevdo], &islong, &sum, -1); } putsect(p); } getdir(f->xf, d, dp->d, dp->addr, dp->offset); if(islong && sum == -1 && nameok(namebuf)) strcpy(d->name, namebuf); } } void rstat(void) { Dir dir; Xfile *f; f = xfile(req->fid, Asis); if(!f || getfile(f) < 0){ errno = Eio; return; } dir.name = repdata; dostat(f, &dir); rep->nstat = convD2M(&dir, statbuf, sizeof statbuf); rep->stat = statbuf; putfile(f); } void rwstat(void) { Dir dir, wdir; Xfile *f, pf; Dosptr *dp, ndp, pdp; Iosect *parp; Dosdir *pard, *d, od; char sname[13]; ulong oaddr, ooffset, length; long start; int i, longtype, changes, attr; f = xfile(req->fid, Asis); if(!f || getfile(f) < 0){ errno = Eio; return; } dp = f->ptr; if(isroot(dp->addr)){ errno = Eperm; goto out; } changes = 0; dir.name = repdata; dostat(f, &dir); if(convM2D(req->stat, req->nstat, &wdir, (char*)statbuf) != req->nstat){ errno = Ebadstat; goto out; } /* * To change length, must have write permission on file. * we only allow truncates for now. */ if(wdir.length!=~0 && wdir.length!=dir.length){ if(wdir.length > dir.length || !dir.mode & 0222){ errno = Eperm; goto out; } } /* * no chown or chgrp */ if(wdir.uid[0] != '\0' && strcmp(dir.uid, wdir.uid) != 0 || wdir.gid[0] != '\0' && strcmp(dir.gid, wdir.gid) != 0){ errno = Eperm; goto out; } /* * mode/mtime allowed */ if(wdir.mtime != ~0 && dir.mtime != wdir.mtime) changes = 1; /* * Setting DMAPPEND (make system file contiguous) * requires setting DMEXCL (system file). */ if(wdir.mode != ~0){ if((wdir.mode & 7) != ((wdir.mode >> 3) & 7) || (wdir.mode & 7) != ((wdir.mode >> 6) & 7)){ errno = Eperm; goto out; } if((dir.mode^wdir.mode) & (DMEXCL|DMAPPEND|0777)) changes = 1; if((dir.mode^wdir.mode) & DMAPPEND) { if((wdir.mode & (DMEXCL|DMAPPEND)) == DMAPPEND) { errno = Eperm; goto out; } if((wdir.mode & DMAPPEND) && makecontig(f, 0) < 0) { errno = Econtig; goto out; } } } /* * to rename: * 1) make up a fake clone * 2) walk to parent * 3) remove the old entry * 4) create entry with new name * 5) write correct mode/mtime info * we need to remove the old entry before creating the new one * to avoid a lock loop. */ if(wdir.name[0] != '\0' && strcmp(dir.name, wdir.name) != 0){ if(utflen(wdir.name) >= DOSNAMELEN){ errno = Etoolong; goto out; } /* * grab parent directory of file to be changed and check for write perm * rename also disallowed for read-only files in root directory */ parp = getsect(f->xf, dp->paddr); if(parp == nil){ errno = Eio; goto out; } pard = (Dosdir *)&parp->iobuf[dp->poffset]; if(!isroot(dp->paddr) && (pard->attr & DRONLY) || isroot(dp->paddr) && (dp->d->attr&DRONLY)){ putsect(parp); errno = Eperm; goto out; } /* * retrieve info from old entry */ oaddr = dp->addr; ooffset = dp->offset; d = dp->d; od = *d; start = getstart(f->xf, d); length = GLONG(d->length); attr = d->attr; /* * temporarily release file to allow other directory ops: * walk to parent, validate new name * then remove old entry */ putfile(f); pf = *f; memset(&pdp, 0, sizeof(Dosptr)); pdp.prevaddr = -1; pdp.naddr = -1; pdp.addr = dp->paddr; pdp.offset = dp->poffset; pdp.p = parp; if(!isroot(pdp.addr)) pdp.d = (Dosdir *)&parp->iobuf[pdp.offset]; pf.ptr = &pdp; longtype = mk8dot3name(&pf, &ndp, wdir.name, sname); if(longtype==Invalid){ putsect(parp); errno = Eperm; return; } if(getfile(f) < 0){ putsect(parp); errno = Eio; return; } doremove(f->xf, dp); putfile(f); /* * search for dir entry again, since we may be able to use the old slot, * and we need to set up the naddr field if a long name spans the block. * create new entry. */ if(searchdir(&pf, wdir.name, dp, 1, longtype) < 0 || mkdentry(pf.xf, dp, wdir.name, sname, longtype, attr, start, length) < 0){ putsect(parp); errno = Eio; goto out; } /* * copy invisible fields */ d = dp->d; d->ctimetenth = od.ctimetenth; for(i = 0; i < nelem(od.ctime); i++) d->ctime[i] = od.ctime[i]; for(i = 0; i < nelem(od.cdate); i++) d->cdate[i] = od.cdate[i]; for(i = 0; i < nelem(od.adate); i++) d->adate[i] = od.adate[i]; putsect(parp); /* * relocate up other fids to the same file, if it moved */ f->qid.path = QIDPATH(dp); if(oaddr != dp->addr || ooffset != dp->offset) dosptrreloc(f, dp, oaddr, ooffset); /* * copy fields that are not supposed to change */ if(wdir.mtime == ~0) wdir.mtime = dir.mtime; if(wdir.mode == ~0) wdir.mode = dir.mode; changes = 1; } /* * do the actual truncate */ if(wdir.length != ~0 && wdir.length != dir.length && truncfile(f, wdir.length) < 0) errno = Eio; if(changes){ putdir(dp->d, &wdir); dp->p->flags |= BMOD; } out: putfile(f); sync(); }