ref: 11025d6f4a2c3c7e75010f85c2d3108e602270b7
dir: /sys/src/cmd/hjfs/fs2.c/
#include <u.h> #include <libc.h> #include <thread.h> #include <fcall.h> #include "dat.h" #include "fns.h" Chan * chanattach(Fs *fs, int flags) { Chan *ch; ch = emalloc(sizeof(*ch)); ch->fs = fs; ch->flags = flags; ch->loc = cloneloc(fs, (flags & CHFDUMP) != 0 ? fs->dumprootloc : fs->rootloc); return ch; } Chan * chanclone(Chan *ch) { Chan *d; chbegin(ch); d = emalloc(sizeof(*d)); d->fs = ch->fs; d->flags = ch->flags; d->uid = ch->uid; d->loc = cloneloc(ch->fs, ch->loc); chend(ch); return d; } int chanwalk(Chan *ch, char *name) { Buf *b; Dentry *d; Loc *l; FLoc f; if(name == nil || name[0] == 0 || name[0] == '.' && name[1] == 0) return 1; chbegin(ch); if(ch->open != 0){ werrstr(Einval); chend(ch); return -1; } b = getbuf(ch->fs->d, ch->loc->blk, TDENTRY, 0); if(b == nil){ chend(ch); return -1; } d = getdent(ch->loc, b); if(d == nil) goto error; if((d->type & QTDIR) == 0){ werrstr(Enotadir); goto error; } if(!permcheck(ch->fs, d, ch->uid, OEXEC)){ werrstr(Eperm); goto error; } if(strcmp(name, "..") == 0){ l = ch->loc->next; if(l == nil) goto done; putloc(ch->fs, ch->loc, 0); ch->loc = l; goto done; } if(findentry(ch->fs, ch->loc, b, name, &f, ch->flags & CHFDUMP) <= 0) goto error; ch->loc = getloc(ch->fs, f, ch->loc); done: putbuf(b); chend(ch); return 1; error: putbuf(b); chend(ch); return -1; } int namevalid(char *name) { char *p; if(name == nil || name[0] == 0) return 0; if(name[0] == '.' && (name[1] == 0 || name[1] == '.' && name[2] == 0)) return 0; for(p = name; *p; p++) if((uchar) *p < ' ' || *p == '/') return 0; return p - name < NAMELEN; } int chancreat(Chan *ch, char *name, int perm, int mode) { Buf *b; Dentry *d; int isdir; Loc *l; FLoc f; short pgid; b = nil; l = nil; chbegin(ch); if(!namevalid(name) || ch->open != 0) goto inval; if((ch->flags & CHFRO) != 0) goto inval; if(willmodify(ch->fs, ch->loc, ch->flags & CHFNOLOCK) < 0) goto error; if(isdir = ((perm & DMDIR) != 0)) if((mode & (OWRITE | OEXEC | ORCLOSE | OTRUNC)) != 0) goto inval; b = getbuf(ch->fs->d, ch->loc->blk, TDENTRY, 0); if(b == nil) goto error; d = getdent(ch->loc, b); if(d == nil) goto error; if((d->type & QTDIR) == 0){ werrstr(Enotadir); goto error; } if((ch->flags & CHFNOPERM) == 0){ if(!permcheck(ch->fs, d, ch->uid, OWRITE)){ werrstr(Eperm); goto error; } if(isdir) perm &= ~0777 | d->mode & 0777; else perm &= ~0666 | d->mode & 0666; } if(newentry(ch->fs, ch->loc, b, name, &f, 0) <= 0) goto error; f.type = perm >> 24; if(newqid(ch->fs, &f.path) < 0) goto error; l = getloc(ch->fs, f, ch->loc); modified(ch, d); b->op |= BDELWRI; pgid = d->gid; putbuf(b); b = nil; if(willmodify(ch->fs, l, ch->flags & CHFNOLOCK) < 0) goto error; b = getbuf(ch->fs->d, l->blk, TDENTRY, 0); if(b == nil) goto error; ch->loc = l; d = &b->de[l->deind]; memset(d, 0, sizeof(*d)); d->Qid = l->Qid; strcpy(d->name, name); d->mtime = time(0); d->atime = d->mtime; d->gid = pgid; d->uid = d->muid = ch->uid; d->mode = DALLOC | perm & 0777; if((d->type & QTEXCL) != 0){ qlock(&ch->loc->ex); ch->loc->exlock = ch; ch->loc->lwrite = d->atime; qunlock(&ch->loc->ex); } b->op |= BDELWRI; putbuf(b); switch(mode & OEXEC){ case ORDWR: ch->open |= CHREAD; case OWRITE: ch->open |= CHWRITE; break; case OEXEC: case OREAD: ch->open |= CHREAD; break; } if((mode & ORCLOSE) != 0) ch->open |= CHRCLOSE; chend(ch); return 1; inval: werrstr(Einval); error: if(l != nil) putloc(ch->fs, l, 0); if(b != nil) putbuf(b); chend(ch); return -1; } int chanopen(Chan *ch, int mode) { Buf *b; Dentry *d; b = nil; chbegin(ch); if(ch->open != 0) goto inval; if((ch->flags & CHFRO) != 0 && (mode & (ORCLOSE | OTRUNC | OWRITE | ORDWR)) != 0) goto inval; if((mode & OTRUNC) != 0) if(willmodify(ch->fs, ch->loc, ch->flags & CHFNOLOCK) < 0) goto error; if((mode & ORCLOSE) != 0){ if(ch->loc->next == nil) goto inval; b = getbuf(ch->fs->d, ch->loc->next->blk, TDENTRY, 0); if(b == nil) goto error; d = getdent(ch->loc->next, b); if(d == nil) goto error; if((ch->flags & CHFNOPERM) == 0) if(!permcheck(ch->fs, d, ch->uid, OWRITE)) goto perm; putbuf(b); } b = getbuf(ch->fs->d, ch->loc->blk, TDENTRY, 0); if(b == nil) goto error; d = getdent(ch->loc, b); if(d == nil) goto error; if((d->type & QTAPPEND) != 0) mode &= ~OTRUNC; if((d->type & QTDIR) != 0 && (mode & (ORCLOSE | OTRUNC | OWRITE | ORDWR)) != 0) goto inval; if((ch->flags & CHFNOPERM) == 0){ if(!permcheck(ch->fs, d, ch->uid, mode & OEXEC)) goto perm; if((mode & OTRUNC) != 0 && !permcheck(ch->fs, d, ch->uid, OWRITE)) goto perm; } if((ch->loc->type & QTEXCL) != 0){ qlock(&ch->loc->ex); if(ch->loc->exlock == nil || ch->loc->lwrite < time(0) - EXCLDUR){ ch->loc->exlock = ch; ch->loc->lwrite = time(0); qunlock(&ch->loc->ex); }else{ qunlock(&ch->loc->ex); werrstr(Elocked); goto error; } } switch(mode & OEXEC){ case ORDWR: ch->open |= CHREAD; case OWRITE: ch->open |= CHWRITE; break; case OEXEC: case OREAD: ch->open |= CHREAD; break; } if((mode & OTRUNC) != 0){ trunc(ch->fs, ch->loc, b, 0); modified(ch, d); b->op |= BDELWRI; } if((mode & ORCLOSE) != 0) ch->open |= CHRCLOSE; putbuf(b); chend(ch); return 1; inval: werrstr(Einval); goto error; perm: werrstr(Eperm); error: if(b != nil) putbuf(b); chend(ch); return -1; } static int checklock(Chan *ch) { int rc; qlock(&ch->loc->ex); rc = 1; if(ch->loc->exlock == ch){ if(ch->loc->lwrite < time(0) - EXCLDUR){ ch->loc->exlock = nil; werrstr("lock broken"); rc = -1; }else ch->loc->lwrite = time(0); }else{ werrstr(Elocked); rc = -1; } qunlock(&ch->loc->ex); return rc; } int chanwrite(Chan *ch, void *buf, ulong n, uvlong off) { uvlong i, e, bl; int r, rn, rc; Buf *b, *c; Dentry *d; uchar *p; if(n == 0) return 0; if((ch->flags & CHFRO) != 0){ werrstr(Einval); return -1; } if((ch->open & CHWRITE) == 0){ werrstr(Einval); return -1; } chbegin(ch); if((ch->loc->type & QTEXCL) != 0 && checklock(ch) < 0){ chend(ch); return -1; } if(willmodify(ch->fs, ch->loc, ch->flags & CHFNOLOCK) < 0){ chend(ch); return -1; } b = getbuf(ch->fs->d, ch->loc->blk, TDENTRY, 0); if(b == nil){ chend(ch); return -1; } d = getdent(ch->loc, b); if(d == nil){ putbuf(b); chend(ch); return -1; } if((d->type & QTAPPEND) != 0) off = d->size; e = off + n; i = off; p = buf; while(i < e){ bl = i / RBLOCK; r = i % RBLOCK; rn = RBLOCK - r; if(i + rn > e) rn = e - i; rc = getblk(ch->fs, ch->loc, b, bl, &bl, rn == RBLOCK ? GBOVERWR : GBCREATE); if(rc < 0) goto done; c = getbuf(ch->fs->d, bl, TRAW, rc == 0 || rn == RBLOCK); if(c == nil) goto done; if(rc == 0 && rn != RBLOCK) memset(c->data, 0, sizeof(c->data)); memcpy(c->data + r, p, rn); i += rn; c->op |= i != e ? BWRIM : BDELWRI; putbuf(c); p += rn; } done: modified(ch, d); e = off + (p - (uchar *) buf); if(e > d->size) d->size = e; b->op |= BDELWRI; putbuf(b); chend(ch); if(p == buf) return -1; return p - (uchar *) buf; } static int chandirread(Chan *, void *, ulong, uvlong); int chanread(Chan *ch, void *buf, ulong n, uvlong off) { uvlong i, e, bl; int r, rn, rc; uchar *p; Buf *b, *c; Dentry *d; if((ch->open & CHREAD) == 0){ werrstr(Einval); return -1; } chbegin(ch); if((ch->loc->type & QTEXCL) != 0 && checklock(ch) < 0){ chend(ch); return -1; } if((ch->loc->Qid.type & QTDIR) != 0) return chandirread(ch, buf, n, off); b = getbuf(ch->fs->d, ch->loc->blk, TDENTRY, 0); if(b == nil){ chend(ch); return -1; } d = getdent(ch->loc, b); if(d == nil) goto error; if(off >= d->size) n = 0; else if(off + n > d->size) n = d->size - off; if(n == 0){ putbuf(b); chend(ch); return 0; } e = off + n; i = off; p = buf; while(i < e){ bl = i / RBLOCK; r = i % RBLOCK; rn = RBLOCK - r; if(i + rn > e) rn = e - i; rc = getblk(ch->fs, ch->loc, b, bl, &bl, GBREAD); if(rc < 0) goto error; if(rc == 0) memset(p, 0, rn); else{ c = getbuf(ch->fs->d, bl, TRAW, 0); if(c == nil) goto error; memcpy(p, c->data + r, rn); putbuf(c); } i += rn; p += rn; } putbuf(b); chend(ch); return n; error: putbuf(b); chend(ch); return -1; } static void statbuf(Fs *fs, Dentry *d, Dir *di, char *buf) { di->qid = d->Qid; di->mode = (d->mode & 0777) | (d->Qid.type << 24); di->mtime = d->mtime; di->atime = d->atime; di->length = d->size; if(d->type & QTDIR) di->length = 0; if(buf == nil){ di->name = estrdup(d->name); di->uid = uid2name(fs, d->uid, nil); di->gid = uid2name(fs, d->gid, nil); di->muid = uid2name(fs, d->muid, nil); }else{ memset(buf, 0, NAMELEN + 3 * USERLEN); strncpy(buf, d->name, NAMELEN - 1); di->name = buf; di->uid = uid2name(fs, d->uid, buf + NAMELEN); di->gid = uid2name(fs, d->gid, buf + NAMELEN + USERLEN); di->muid = uid2name(fs, d->muid, buf + NAMELEN + 2 * USERLEN); } } int chanstat(Chan *ch, Dir *di) { Buf *b; Dentry *d; chbegin(ch); b = getbuf(ch->fs->d, ch->loc->blk, TDENTRY, 0); if(b == nil){ chend(ch); return -1; } d = getdent(ch->loc, b); if(d == nil){ putbuf(b); chend(ch); return -1; } statbuf(ch->fs, d, di, nil); putbuf(b); chend(ch); return 0; } static int chandirread(Chan *ch, void *buf, ulong n, uvlong off) { Buf *b, *c; Dentry *d; uvlong i, blk; int j; int rc; ulong wr; Dir di; char cbuf[NAMELEN + 3 * USERLEN]; if(off == 0){ ch->dwloff = 0; ch->dwblk = 0; ch->dwind = 0; }else if(ch->dwloff != off){ werrstr(Einval); chend(ch); return -1; } b = getbuf(ch->fs->d, ch->loc->blk, TDENTRY, 0); if(b == nil){ chend(ch); return -1; } d = getdent(ch->loc, b); if(d == nil){ putbuf(b); chend(ch); return -1; } if(ch->dwblk >= d->size){ putbuf(b); chend(ch); return 0; } c = nil; wr = 0; i = ch->dwblk; j = ch->dwind; for(;;){ if(c == nil){ rc = getblk(ch->fs, ch->loc, b, i, &blk, GBREAD); if(rc < 0) goto error; if(rc == 0){ j = 0; if(++i >= d->size) break; continue; } c = getbuf(ch->fs->d, blk, TDENTRY, 0); if(c == nil) goto error; } if((c->de[j].mode & DALLOC) == 0) goto next; if((ch->flags & CHFDUMP) != 0 && (c->de[j].type & QTTMP) != 0) goto next; statbuf(ch->fs, &c->de[j], &di, cbuf); rc = convD2M(&di, (uchar *) buf + wr, n - wr); if(rc <= BIT16SZ) break; wr += rc; next: if(++j >= DEPERBLK){ j = 0; if(c != nil) putbuf(c); c = nil; if(++i >= d->size) break; } } ch->dwblk = i; ch->dwind = j; ch->dwloff += wr; if(c != nil) putbuf(c); putbuf(b); chend(ch); return wr; error: putbuf(b); chend(ch); return -1; } int chanclunk(Chan *ch) { Buf *b, *p; int rc; Dentry *d; rc = 1; b = p = nil; chbegin(ch); if(ch->open & CHRCLOSE){ if((ch->flags & CHFRO) != 0) goto inval; if(willmodify(ch->fs, ch->loc, ch->flags & CHFNOLOCK) < 0) goto error; if(ch->loc->next == nil) goto inval; p = getbuf(ch->fs->d, ch->loc->next->blk, TDENTRY, 0); if(p == nil) goto error; b = getbuf(ch->fs->d, ch->loc->blk, TDENTRY, 0); if(b == nil) goto error; d = getdent(ch->loc->next, p); if(d == nil) goto error; if((ch->flags & CHFNOPERM) == 0) if(!permcheck(ch->fs, d, ch->uid, OWRITE)){ werrstr(Eperm); goto error; } d = getdent(ch->loc, b); if(d == nil) goto error; if((d->type & QTDIR) != 0 && findentry(ch->fs, ch->loc, b, nil, nil, ch->flags & CHFDUMP) != 0) goto inval; if((d->mode & DGONE) != 0) goto done; qlock(&ch->fs->loctree); if(ch->loc->ref > 1){ d->mode &= ~DALLOC; d->mode |= DGONE; /* aaaaand it's gone */ ch->loc->flags |= LGONE; qunlock(&ch->fs->loctree); }else{ ch->loc->flags &= ~LGONE; qunlock(&ch->fs->loctree); rc = delete(ch->fs, ch->loc, b); } b->op |= BDELWRI; } done: if(b != nil) putbuf(b); if(p != nil) putbuf(p); if((ch->loc->type & QTEXCL) != 0){ qlock(&ch->loc->ex); if(ch->loc->exlock == ch) ch->loc->exlock = nil; qunlock(&ch->loc->ex); } putloc(ch->fs, ch->loc, 1); chend(ch); free(ch); return rc; inval: werrstr(Einval); error: rc = -1; goto done; } int chanwstat(Chan *ch, Dir *di) { Buf *b, *pb; Dentry *d; int isdir, owner, rc; short nuid, ngid; b = pb = nil; chbegin(ch); if((ch->flags & CHFRO) != 0) goto inval; if(willmodify(ch->fs, ch->loc, ch->flags & CHFNOLOCK) < 0) goto error; if(*di->name){ FLoc f; if(!namevalid(di->name) || ch->loc->next == nil) goto inval; pb = getbuf(ch->fs->d, ch->loc->next->blk, TDENTRY, 0); if(pb == nil) goto error; d = getdent(ch->loc->next, pb); if(d == nil) goto error; rc = findentry(ch->fs, ch->loc->next, pb, di->name, &f, ch->flags & CHFDUMP); if(rc < 0) goto error; else if(rc == 0){ if((ch->flags & CHFNOPERM) == 0) if(!permcheck(ch->fs, d, ch->uid, OWRITE)) goto perm; } else if(f.blk != ch->loc->blk || f.deind != ch->loc->deind){ werrstr(Eexists); goto error; } } b = getbuf(ch->fs->d, ch->loc->blk, TDENTRY, 0); if(b == nil) goto error; d = getdent(ch->loc, b); if(d == nil) goto error; isdir = (d->type & QTDIR) != 0; owner = ch->uid == d->uid || ingroup(ch->fs, ch->uid, d->gid, 1) || (ch->fs->flags & FSNOPERM) != 0 || (ch->flags & CHFNOPERM) != 0; if(di->length != ~0){ if(isdir && di->length != 0) goto inval; if((ch->flags & CHFNOPERM) == 0) if(di->length != d->size && !permcheck(ch->fs, d, ch->uid, OWRITE)) goto perm; } if(di->mtime != ~0 && !owner) goto perm; if(di->mode != ~0 && !owner) goto perm; nuid = d->uid; ngid = d->gid; if(*di->uid != 0 && name2uid(ch->fs, di->uid, &nuid) < 0) goto inval; if(*di->gid != 0 && name2uid(ch->fs, di->gid, &ngid) < 0) goto inval; if(nuid != d->uid && (ch->fs->flags & FSCHOWN) == 0) goto perm; if((nuid != d->uid || ngid != d->gid) && !owner) goto perm; d->uid = nuid; d->gid = ngid; if(di->length != ~0 && di->length != d->size && !isdir){ trunc(ch->fs, ch->loc, b, di->length); modified(ch, d); } if(di->mtime != ~0) d->mtime = di->mtime; if(di->mode != ~0){ d->mode = d->mode & ~0777 | di->mode & 0777; ch->loc->type = d->type = di->mode >> 24; } if(*di->name){ memset(d->name, 0, NAMELEN); strcpy(d->name, di->name); } b->op |= BDELWRI; if(pb != nil) putbuf(pb); putbuf(b); chend(ch); return 1; inval: werrstr(Einval); goto error; perm: werrstr(Eperm); error: if(pb != nil) putbuf(pb); if(b != nil) putbuf(b); chend(ch); return -1; } int chanremove(Chan *ch) { ch->open |= CHRCLOSE; return chanclunk(ch); }