ref: 689109303467790df972f16918ee48a490c53f56
dir: /sys/src/cmd/acme/fsys.c/
#include <u.h> #include <libc.h> #include <draw.h> #include <thread.h> #include <cursor.h> #include <mouse.h> #include <keyboard.h> #include <frame.h> #include <fcall.h> #include <plumb.h> #include "dat.h" #include "fns.h" static int cfd; static int sfd; enum { Nhash = 16, DEBUG = 0 }; static Fid *fids[Nhash]; Fid *newfid(int); static Xfid* fsysflush(Xfid*, Fid*); static Xfid* fsysauth(Xfid*, Fid*); static Xfid* fsysversion(Xfid*, Fid*); static Xfid* fsysattach(Xfid*, Fid*); static Xfid* fsyswalk(Xfid*, Fid*); static Xfid* fsysopen(Xfid*, Fid*); static Xfid* fsyscreate(Xfid*, Fid*); static Xfid* fsysread(Xfid*, Fid*); static Xfid* fsyswrite(Xfid*, Fid*); static Xfid* fsysclunk(Xfid*, Fid*); static Xfid* fsysremove(Xfid*, Fid*); static Xfid* fsysstat(Xfid*, Fid*); static Xfid* fsyswstat(Xfid*, Fid*); Xfid* (*fcall[Tmax])(Xfid*, Fid*) = { [Tflush] = fsysflush, [Tversion] = fsysversion, [Tauth] = fsysauth, [Tattach] = fsysattach, [Twalk] = fsyswalk, [Topen] = fsysopen, [Tcreate] = fsyscreate, [Tread] = fsysread, [Twrite] = fsyswrite, [Tclunk] = fsysclunk, [Tremove]= fsysremove, [Tstat] = fsysstat, [Twstat] = fsyswstat, }; char Eperm[] = "permission denied"; char Eexist[] = "file does not exist"; char Enotdir[] = "not a directory"; Dirtab dirtab[]= { { ".", QTDIR, Qdir, 0500|DMDIR }, { "acme", QTDIR, Qacme, 0500|DMDIR }, { "cons", QTFILE, Qcons, 0600 }, { "consctl", QTFILE, Qconsctl, 0000 }, { "draw", QTDIR, Qdraw, 0000|DMDIR }, /* to suppress graphics progs started in acme */ { "editout", QTFILE, Qeditout, 0200 }, { "index", QTFILE, Qindex, 0400 }, { "label", QTFILE, Qlabel, 0600 }, { "new", QTDIR, Qnew, 0500|DMDIR }, { nil, } }; Dirtab dirtabw[]= { { ".", QTDIR, Qdir, 0500|DMDIR }, { "addr", QTFILE, QWaddr, 0600 }, { "body", QTAPPEND, QWbody, 0600|DMAPPEND }, { "ctl", QTFILE, QWctl, 0600 }, { "data", QTFILE, QWdata, 0600 }, { "editout", QTFILE, QWeditout, 0200 }, { "errors", QTFILE, QWerrors, 0200 }, { "event", QTFILE, QWevent, 0600 }, { "rdsel", QTFILE, QWrdsel, 0400 }, { "wrsel", QTFILE, QWwrsel, 0200 }, { "tag", QTAPPEND, QWtag, 0600|DMAPPEND }, { "xdata", QTFILE, QWxdata, 0600 }, { nil, } }; typedef struct Mnt Mnt; struct Mnt { QLock; int id; Mntdir *md; }; Mnt mnt; Xfid* respond(Xfid*, Fcall*, char*); int dostat(int, Dirtab*, uchar*, int, uint); uint getclock(void); char *user = "Wile E. Coyote"; int clockfd; static int closing = 0; int messagesize = Maxblock+IOHDRSZ; /* good start */ void fsysproc(void *); void fsysinit(void) { int p[2]; int n, fd; char buf[256]; if(pipe(p) < 0) error("can't create pipe"); cfd = p[0]; sfd = p[1]; fmtinstall('F', fcallfmt); clockfd = open("/dev/time", OREAD|OCEXEC); fd = open("/dev/user", OREAD); if(fd >= 0){ n = read(fd, buf, sizeof buf-1); if(n > 0){ buf[n] = 0; user = estrdup(buf); } close(fd); } proccreate(fsysproc, nil, STACK); } void fsysproc(void *) { int n; Xfid *x; Fid *f; Fcall t; uchar *buf; x = nil; for(;;){ buf = emalloc(messagesize+UTFmax); /* overflow for appending partial rune in xfidwrite */ n = read9pmsg(sfd, buf, messagesize); if(n <= 0){ if(closing) break; error("i/o error on server channel"); } if(x == nil){ sendp(cxfidalloc, nil); x = recvp(cxfidalloc); } x->buf = buf; if(convM2S(buf, n, x) != n) error("convert error in convM2S"); if(DEBUG) fprint(2, "%F\n", &x->Fcall); if(fcall[x->type] == nil) x = respond(x, &t, "bad fcall type"); else{ switch(x->type){ case Tversion: case Tauth: case Tflush: f = nil; break; case Tattach: f = newfid(x->fid); break; default: f = newfid(x->fid); if(!f->busy){ x->f = f; x = respond(x, &t, "fid not in use"); continue; } break; } x->f = f; x = (*fcall[x->type])(x, f); } } } Mntdir* fsysaddid(Rune *dir, int ndir, Rune **incl, int nincl) { Mntdir *m; int id; qlock(&mnt); id = ++mnt.id; m = emalloc(sizeof *m); m->id = id; m->dir = dir; m->ref = 1; /* one for Command, one will be incremented in attach */ m->ndir = ndir; m->next = mnt.md; m->incl = incl; m->nincl = nincl; mnt.md = m; qunlock(&mnt); return m; } void fsysincid(Mntdir *m) { qlock(&mnt); m->ref++; qunlock(&mnt); } void fsysdelid(Mntdir *idm) { Mntdir *m, *prev; int i; char buf[64]; if(idm == nil) return; qlock(&mnt); if(--idm->ref > 0){ qunlock(&mnt); return; } prev = nil; for(m=mnt.md; m; m=m->next){ if(m == idm){ if(prev) prev->next = m->next; else mnt.md = m->next; for(i=0; i<m->nincl; i++) free(m->incl[i]); free(m->incl); free(m->dir); free(m); qunlock(&mnt); return; } prev = m; } qunlock(&mnt); sprint(buf, "fsysdelid: can't find id %d\n", idm->id); sendp(cerr, estrdup(buf)); } /* * Called only in exec.c:/^run(), from a different FD group */ Mntdir* fsysmount(Rune *dir, int ndir, Rune **incl, int nincl) { char buf[256]; Mntdir *m; /* close server side so don't hang if acme is half-exited */ close(sfd); m = fsysaddid(dir, ndir, incl, nincl); sprint(buf, "%d", m->id); if(mount(cfd, -1, "/mnt/acme", MREPL, buf) < 0){ fsysdelid(m); return nil; } close(cfd); bind("/mnt/acme", "/mnt/wsys", MREPL); if(bind("/mnt/acme", "/dev", MBEFORE) < 0){ fsysdelid(m); return nil; } return m; } void fsysclose(void) { closing = 1; close(cfd); close(sfd); } Xfid* respond(Xfid *x, Fcall *t, char *err) { int n; if(err){ t->type = Rerror; t->ename = err; }else t->type = x->type+1; t->fid = x->fid; t->tag = x->tag; if(x->buf == nil) x->buf = emalloc(messagesize); n = convS2M(t, x->buf, messagesize); if(n <= 0) error("convert error in convS2M"); if(write(sfd, x->buf, n) != n) error("write error in respond"); free(x->buf); x->buf = nil; if(DEBUG) fprint(2, "r: %F\n", t); return x; } static Xfid* fsysversion(Xfid *x, Fid*) { Fcall t; if(x->msize < 256) return respond(x, &t, "version: message size too small"); messagesize = x->msize; t.msize = messagesize; if(strncmp(x->version, "9P2000", 6) != 0) return respond(x, &t, "unrecognized 9P version"); t.version = "9P2000"; return respond(x, &t, nil); } static Xfid* fsysauth(Xfid *x, Fid*) { Fcall t; return respond(x, &t, "acme: authentication not required"); } static Xfid* fsysflush(Xfid *x, Fid*) { sendp(x->c, xfidflush); return nil; } static Xfid* fsysattach(Xfid *x, Fid *f) { Fcall t; int id; Mntdir *m; if(strcmp(x->uname, user) != 0) return respond(x, &t, Eperm); f->busy = TRUE; f->open = FALSE; f->qid.path = Qdir; f->qid.type = QTDIR; f->qid.vers = 0; f->dir = dirtab; f->nrpart = 0; f->w = nil; t.qid = f->qid; f->mntdir = nil; id = atoi(x->aname); qlock(&mnt); for(m=mnt.md; m; m=m->next) if(m->id == id){ f->mntdir = m; m->ref++; break; } if(m == nil) sendp(cerr, estrdup("unknown id in attach")); qunlock(&mnt); return respond(x, &t, nil); } static Xfid* fsyswalk(Xfid *x, Fid *f) { Fcall t; int c, i, j, id; Qid q; uchar type; ulong path; Fid *nf; Dirtab *d, *dir; Window *w; char *err; nf = nil; w = nil; if(f->open) return respond(x, &t, "walk of open file"); if(x->fid != x->newfid){ nf = newfid(x->newfid); if(nf->busy) return respond(x, &t, "newfid already in use"); nf->busy = TRUE; nf->open = FALSE; nf->mntdir = f->mntdir; if(f->mntdir) f->mntdir->ref++; nf->dir = f->dir; nf->qid = f->qid; nf->w = f->w; nf->nrpart = 0; /* not open, so must be zero */ if(nf->w) incref(nf->w); f = nf; /* walk f */ } t.nwqid = 0; err = nil; dir = nil; id = WIN(f->qid); q = f->qid; if(x->nwname > 0){ for(i=0; i<x->nwname; i++){ if((q.type & QTDIR) == 0){ err = Enotdir; break; } if(strcmp(x->wname[i], "..") == 0){ type = QTDIR; path = Qdir; id = 0; if(w){ winclose(w); w = nil; } Accept: if(i == MAXWELEM){ err = "name too long"; break; } q.type = type; q.vers = 0; q.path = QID(id, path); t.wqid[t.nwqid++] = q; continue; } /* is it a numeric name? */ for(j=0; (c=x->wname[i][j]); j++) if(c<'0' || '9'<c) goto Regular; /* yes: it's a directory */ if(w) /* name has form 27/23; get out before losing w */ break; id = atoi(x->wname[i]); qlock(&row); w = lookid(id, FALSE); if(w == nil){ qunlock(&row); break; } incref(w); /* we'll drop reference at end if there's an error */ path = Qdir; type = QTDIR; qunlock(&row); dir = dirtabw; goto Accept; Regular: // if(FILE(f->qid) == Qacme) /* empty directory */ // break; if(strcmp(x->wname[i], "new") == 0){ if(w) error("w set in walk to new"); sendp(cnewwindow, nil); /* signal newwindowthread */ w = recvp(cnewwindow); /* receive new window */ incref(w); type = QTDIR; path = QID(w->id, Qdir); id = w->id; dir = dirtabw; goto Accept; } if(id == 0) d = dirtab; else d = dirtabw; d++; /* skip '.' */ for(; d->name; d++) if(strcmp(x->wname[i], d->name) == 0){ path = d->qid; type = d->type; dir = d; goto Accept; } break; /* file not found */ } if(i==0 && err == nil) err = Eexist; } if(err!=nil || t.nwqid<x->nwname){ if(nf){ nf->busy = FALSE; fsysdelid(nf->mntdir); } }else if(t.nwqid == x->nwname){ if(w){ f->w = w; w = nil; /* don't drop the reference */ } if(dir) f->dir = dir; f->qid = q; } if(w != nil) winclose(w); return respond(x, &t, err); } static Xfid* fsysopen(Xfid *x, Fid *f) { Fcall t; int m; /* can't truncate anything, so just disregard */ x->mode &= ~(OTRUNC|OCEXEC); /* can't execute or remove anything */ if(x->mode==OEXEC || (x->mode&ORCLOSE)) goto Deny; switch(x->mode){ default: goto Deny; case OREAD: m = 0400; break; case OWRITE: m = 0200; break; case ORDWR: m = 0600; break; } if(((f->dir->perm&~(DMDIR|DMAPPEND))&m) != m) goto Deny; sendp(x->c, xfidopen); return nil; Deny: return respond(x, &t, Eperm); } static Xfid* fsyscreate(Xfid *x, Fid*) { Fcall t; return respond(x, &t, Eperm); } static int idcmp(void *a, void *b) { return *(int*)a - *(int*)b; } static Xfid* fsysread(Xfid *x, Fid *f) { Fcall t; uchar *b; int i, id, n, o, e, j, k, *ids, nids; Dirtab *d, dt; Column *c; uint clock, len; char buf[16]; if(f->qid.type & QTDIR){ if(FILE(f->qid) == Qacme){ /* empty dir */ t.data = nil; t.count = 0; respond(x, &t, nil); return x; } o = x->offset; e = x->offset+x->count; clock = getclock(); b = emalloc(messagesize); id = WIN(f->qid); n = 0; if(id > 0) d = dirtabw; else d = dirtab; d++; /* first entry is '.' */ for(i=0; d->name!=nil && i<e; i+=len){ len = dostat(WIN(x->f->qid), d, b+n, x->count-n, clock); if(len <= BIT16SZ) break; if(i >= o) n += len; d++; } if(id == 0){ qlock(&row); nids = 0; ids = nil; for(j=0; j<row.ncol; j++){ c = row.col[j]; for(k=0; k<c->nw; k++){ ids = realloc(ids, (nids+1)*sizeof(int)); ids[nids++] = c->w[k]->id; } } qunlock(&row); qsort(ids, nids, sizeof ids[0], idcmp); j = 0; dt.name = buf; for(; j<nids && i<e; i+=len){ k = ids[j]; sprint(dt.name, "%d", k); dt.qid = QID(k, Qdir); dt.type = QTDIR; dt.perm = DMDIR|0700; len = dostat(k, &dt, b+n, x->count-n, clock); if(len == 0) break; if(i >= o) n += len; j++; } free(ids); } t.data = (char*)b; t.count = n; respond(x, &t, nil); free(b); return x; } sendp(x->c, xfidread); return nil; } static Xfid* fsyswrite(Xfid *x, Fid*) { sendp(x->c, xfidwrite); return nil; } static Xfid* fsysclunk(Xfid *x, Fid *f) { fsysdelid(f->mntdir); sendp(x->c, xfidclose); return nil; } static Xfid* fsysremove(Xfid *x, Fid*) { Fcall t; return respond(x, &t, Eperm); } static Xfid* fsysstat(Xfid *x, Fid *f) { Fcall t; t.stat = emalloc(messagesize-IOHDRSZ); t.nstat = dostat(WIN(x->f->qid), f->dir, t.stat, messagesize-IOHDRSZ, getclock()); x = respond(x, &t, nil); free(t.stat); return x; } static Xfid* fsyswstat(Xfid *x, Fid*) { Fcall t; return respond(x, &t, Eperm); } Fid* newfid(int fid) { Fid *f, *ff, **fh; ff = nil; fh = &fids[fid&(Nhash-1)]; for(f=*fh; f; f=f->next) if(f->fid == fid) return f; else if(ff==nil && f->busy==FALSE) ff = f; if(ff){ ff->fid = fid; return ff; } f = emalloc(sizeof *f); f->fid = fid; f->next = *fh; *fh = f; return f; } uint getclock() { char buf[32]; buf[0] = '\0'; pread(clockfd, buf, sizeof buf, 0); return atoi(buf); } int dostat(int id, Dirtab *dir, uchar *buf, int nbuf, uint clock) { Dir d; d.qid.path = QID(id, dir->qid); d.qid.vers = 0; d.qid.type = dir->type; d.mode = dir->perm; d.length = 0; /* would be nice to do better */ d.name = dir->name; d.uid = user; d.gid = user; d.muid = user; d.atime = clock; d.mtime = clock; return convD2M(&d, buf, nbuf); }