ref: 6ff5c10ffb06d10eee06f1d432f9cc4738496c07
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);
}