ref: 613fd6b4294ad3277a91c9a2e58b2b2d4f22ab1c
dir: /sys/src/cmd/rio/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 "dat.h"
#include "fns.h"
char Eperm[] = "permission denied";
char Eexist[] = "file does not exist";
char Enotdir[] = "not a directory";
char Ebadfcall[] = "bad fcall type";
char Eoffset[] = "illegal offset";
char Enomem[] = "out of memory";
int messagesize = 8192+IOHDRSZ; /* good start */
Dirtab dirtab[]=
{
{ ".", QTDIR, Qdir, 0500|DMDIR },
{ "screen", QTFILE, Qscreen, 0400 },
{ "snarf", QTFILE, Qsnarf, 0600 },
{ "wctl", QTFILE, Qwctl, 0600 },
{ "kbdtap", QTFILE, Qtap, 0660 },
{ "wsys", QTDIR, Qwsys, 0500|DMDIR },
{ "cons", QTFILE, Qcons, 0600 },
{ "cursor", QTFILE, Qcursor, 0600 },
{ "consctl", QTFILE, Qconsctl, 0200 },
{ "winid", QTFILE, Qwinid, 0400 },
{ "winname", QTFILE, Qwinname, 0400 },
{ "label", QTFILE, Qlabel, 0600 },
{ "kbd", QTFILE, Qkbd, 0600 },
{ "mouse", QTFILE, Qmouse, 0600 },
{ "text", QTFILE, Qtext, 0600 },
{ "wdir", QTFILE, Qwdir, 0600 },
{ "window", QTFILE, Qwindow, 0400 },
{ nil, }
};
static uint getclock(void);
static void filsysproc(void*);
static Fid* newfid(Filsys*, int);
static int dostat(Filsys*, int, Dirtab*, uchar*, int, uint);
int clockfd;
int firstmessage = 1;
char srvpipe[64];
char srvwctl[64];
static Xfid* filsysflush(Filsys*, Xfid*, Fid*);
static Xfid* filsysversion(Filsys*, Xfid*, Fid*);
static Xfid* filsysauth(Filsys*, Xfid*, Fid*);
static Xfid* filsysattach(Filsys*, Xfid*, Fid*);
static Xfid* filsyswalk(Filsys*, Xfid*, Fid*);
static Xfid* filsysopen(Filsys*, Xfid*, Fid*);
static Xfid* filsyscreate(Filsys*, Xfid*, Fid*);
static Xfid* filsysread(Filsys*, Xfid*, Fid*);
static Xfid* filsyswrite(Filsys*, Xfid*, Fid*);
static Xfid* filsysclunk(Filsys*, Xfid*, Fid*);
static Xfid* filsysremove(Filsys*, Xfid*, Fid*);
static Xfid* filsysstat(Filsys*, Xfid*, Fid*);
static Xfid* filsyswstat(Filsys*, Xfid*, Fid*);
Xfid* (*fcall[Tmax])(Filsys*, Xfid*, Fid*) =
{
[Tflush] = filsysflush,
[Tversion] = filsysversion,
[Tauth] = filsysauth,
[Tattach] = filsysattach,
[Twalk] = filsyswalk,
[Topen] = filsysopen,
[Tcreate] = filsyscreate,
[Tread] = filsysread,
[Twrite] = filsyswrite,
[Tclunk] = filsysclunk,
[Tremove]= filsysremove,
[Tstat] = filsysstat,
[Twstat] = filsyswstat,
};
void
post(char *name, char *envname, int srvfd)
{
int fd;
char buf[32];
fd = create(name, OWRITE|ORCLOSE|OCEXEC, 0600);
if(fd < 0)
error(name);
snprint(buf, sizeof(buf), "%d", srvfd);
if(write(fd, buf, strlen(buf)) != strlen(buf))
error("srv write");
putenv(envname, name);
}
/*
* Build pipe with OCEXEC set on second fd.
* Can't put it on both because we want to post one in /srv.
*/
int
cexecpipe(int *p0, int *p1)
{
/* pipe the hard way to get close on exec */
if(bind("#|", "/mnt/temp", MREPL) == -1)
return -1;
*p0 = open("/mnt/temp/data", ORDWR);
*p1 = open("/mnt/temp/data1", ORDWR|OCEXEC);
unmount(nil, "/mnt/temp");
if(*p0<0 || *p1<0)
return -1;
return 0;
}
Filsys*
filsysinit(Channel *cxfidalloc)
{
Filsys *fs;
fs = emalloc(sizeof(Filsys));
if(cexecpipe(&fs->cfd, &fs->sfd) < 0)
goto Rescue;
fmtinstall('F', fcallfmt);
clockfd = open("/dev/time", OREAD|OCEXEC);
fs->user = getuser();
fs->csyncflush = chancreate(sizeof(int), 0);
if(fs->csyncflush == nil)
error("chancreate syncflush");
fs->cxfidalloc = cxfidalloc;
proccreate(filsysproc, fs, 10000);
snprint(srvpipe, sizeof(srvpipe), "/srv/rio.%s.%lud", fs->user, (ulong)getpid());
post(srvpipe, "wsys", fs->cfd);
return fs;
Rescue:
free(fs);
return nil;
}
static
void
filsysproc(void *arg)
{
int n;
Xfid *x;
Fid *f;
Fcall t;
uchar *buf;
Filsys *fs;
threadsetname("FILSYSPROC");
fs = arg;
fs->pid = getpid();
x = nil;
for(;;){
buf = malloc(messagesize+UTFmax); /* UTFmax for appending partial rune in xfidwrite */
if(buf == nil)
error(Enomem);
n = read9pmsg(fs->sfd, buf, messagesize);
if(n <= 0){
yield(); /* if threadexitsall'ing, will not return */
fprint(2, "rio: %d: read9pmsg: %d %r\n", getpid(), n);
errorshouldabort = 0;
error("eof or i/o error on server channel");
}
if(x == nil){
send(fs->cxfidalloc, nil);
recv(fs->cxfidalloc, &x);
x->fs = fs;
}
x->buf = buf;
if(convM2S(buf, n, x) != n)
error("convert error in convM2S");
if(debug)
fprint(2, "rio:<-%F\n", &x->Fcall);
if(fcall[x->type] == nil)
x = filsysrespond(fs, x, &t, Ebadfcall);
else{
if(x->type==Tversion || x->type==Tauth)
f = nil;
else
f = newfid(fs, x->fid);
x->f = f;
x = (*fcall[x->type])(fs, x, f);
}
firstmessage = 0;
}
}
/*
* Called only from a different FD group
*/
int
filsysmount(Filsys *fs, int id)
{
char buf[32];
close(fs->sfd); /* close server end so mount won't hang if exiting */
snprint(buf, sizeof buf, "%d", id);
if(mount(fs->cfd, -1, "/mnt/wsys", MREPL, buf) == -1){
fprint(2, "mount failed: %r\n");
return -1;
}
if(bind("/mnt/wsys", "/dev", MBEFORE) == -1){
fprint(2, "bind failed: %r\n");
return -1;
}
return 0;
}
Xfid*
filsysrespond(Filsys *fs, 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)
error("no buffer in respond");
n = convS2M(t, x->buf, messagesize);
if(n <= 0)
error("convert error in convS2M");
if(write(fs->sfd, x->buf, n) != n)
error("write error in respond");
if(debug)
fprint(2, "rio:->%F\n", t);
free(x->buf);
x->buf = nil;
x->flushtag = -1;
return x;
}
void
filsyscancel(Xfid *x)
{
if(x->buf){
free(x->buf);
x->buf = nil;
}
}
static
Xfid*
filsysversion(Filsys *fs, Xfid *x, Fid*)
{
Fcall t;
if(!firstmessage)
return filsysrespond(x->fs, x, &t, "version request not first message");
if(x->msize < 256)
return filsysrespond(x->fs, x, &t, "version: message size too small");
messagesize = x->msize;
t.msize = messagesize;
t.version = "9P2000";
if(strncmp(x->version, "9P", 2) != 0)
t.version = "unknown";
return filsysrespond(fs, x, &t, nil);
}
static
Xfid*
filsysauth(Filsys *fs, Xfid *x, Fid*)
{
Fcall t;
return filsysrespond(fs, x, &t, "rio: authentication not required");
}
static
Xfid*
filsysflush(Filsys *fs, Xfid *x, Fid*)
{
sendp(x->c, xfidflush);
/*
* flushes need to be replied in order. xfidflush() will
* awaken us when the flush has been queued.
*/
recv(fs->csyncflush, nil);
return nil;
}
static
Xfid*
filsysattach(Filsys *, Xfid *x, Fid *f)
{
Fcall t;
if(strcmp(x->uname, x->fs->user) != 0)
return filsysrespond(x->fs, 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;
sendp(x->c, xfidattach);
return nil;
}
static
int
numeric(char *s)
{
for(; *s!='\0'; s++)
if(*s<'0' || '9'<*s)
return 0;
return 1;
}
static
int
skipdir(char *name)
{
/* don't serve these if it's provided in the environment */
if(snarffd>=0 && strcmp(name, "snarf")==0)
return 1;
if(gotscreen && strcmp(name, "screen")==0)
return 1;
if(!servekbd && strcmp(name, "kbd")==0)
return 1;
return 0;
}
static
Xfid*
filsyswalk(Filsys *fs, Xfid *x, Fid *f)
{
Fcall t;
Fid *nf;
int i, id;
uchar type;
ulong path;
Dirtab *d, *dir;
Window *w;
char *err;
Qid qid;
if(f->open)
return filsysrespond(fs, x, &t, "walk of open file");
nf = nil;
if(x->fid != x->newfid){
/* BUG: check exists */
nf = newfid(fs, x->newfid);
if(nf->busy)
return filsysrespond(fs, x, &t, "clone to busy fid");
nf->busy = TRUE;
nf->open = FALSE;
nf->dir = f->dir;
nf->qid = f->qid;
nf->w = f->w;
if(f->w != nil)
incref(f->w);
nf->nrpart = 0; /* not open, so must be zero */
f = nf; /* walk f */
}
t.nwqid = 0;
err = nil;
/* update f->qid, f->dir only if walk completes */
qid = f->qid;
dir = f->dir;
if(x->nwname > 0){
for(i=0; i<x->nwname; i++){
if((qid.type & QTDIR) == 0){
err = Enotdir;
break;
}
if(strcmp(x->wname[i], "..") == 0){
type = QTDIR;
path = Qdir;
dir = dirtab;
if(FILE(qid) == Qwsysdir)
path = Qwsys;
id = 0;
Accept:
if(i == MAXWELEM){
err = "name too long";
break;
}
qid.type = type;
qid.vers = 0;
qid.path = QID(id, path);
t.wqid[t.nwqid++] = qid;
continue;
}
if(qid.path == Qwsys){
/* is it a numeric name? */
if(!numeric(x->wname[i]))
break;
/* yes: it's a directory */
id = atoi(x->wname[i]);
qlock(&all);
w = wlookid(id);
if(w == nil){
qunlock(&all);
break;
}
path = Qwsysdir;
type = QTDIR;
qunlock(&all);
incref(w);
sendp(winclosechan, f->w);
f->w = w;
dir = dirtab;
goto Accept;
}
if(skipdir(x->wname[i]))
break;
id = WIN(f->qid);
d = dirtab;
d++; /* skip '.' */
for(; d->name; d++)
if(strcmp(x->wname[i], d->name) == 0){
if(f->w == nil && d->qid >= Qglobal)
break;
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){
if(nf->w)
sendp(winclosechan, nf->w);
nf->open = FALSE;
nf->busy = FALSE;
}
}else if(t.nwqid == x->nwname){
f->dir = dir;
f->qid = qid;
}
return filsysrespond(fs, x, &t, err);
}
static
Xfid*
filsysopen(Filsys *fs, Xfid *x, Fid *f)
{
Fcall t;
int m;
/* can't truncate anything but Qtext, so just disregard */
if(FILE(f->qid) != Qtext)
x->mode &= ~OTRUNC;
x->mode &= ~OCEXEC;
/* can't execute or remove anything */
if(x->mode==OEXEC || (x->mode&ORCLOSE))
goto Deny;
switch(x->mode & ~OTRUNC){
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 filsysrespond(fs, x, &t, Eperm);
}
static
Xfid*
filsyscreate(Filsys *fs, Xfid *x, Fid*)
{
Fcall t;
return filsysrespond(fs, x, &t, Eperm);
}
static
int
idcmp(void *a, void *b)
{
return *(int*)a - *(int*)b;
}
static
Xfid*
filsysread(Filsys *fs, Xfid *x, Fid *f)
{
Fcall t;
uchar *b;
int i, n, o, e, len, j, k, *ids;
Dirtab *d, dt;
uint clock;
char buf[32];
if((f->qid.type & QTDIR) == 0){
sendp(x->c, xfidread);
return nil;
}
o = x->offset;
e = x->offset+x->count;
clock = getclock();
b = malloc(messagesize-IOHDRSZ); /* avoid memset of emalloc */
if(b == nil)
return filsysrespond(fs, x, &t, Enomem);
n = 0;
switch(FILE(f->qid)){
case Qdir:
case Qwsysdir:
d = dirtab;
d++; /* first entry is '.' */
for(i=0; d->name!=nil && i<e; d++){
if(skipdir(d->name))
continue;
if(f->w == nil && d->qid >= Qglobal)
continue;
len = dostat(fs, WIN(x->f->qid), d, b+n, x->count-n, clock);
if(len <= BIT16SZ)
break;
if(i >= o)
n += len;
i += len;
}
break;
case Qwsys:
qlock(&all);
ids = emalloc(nwindow*sizeof(int));
for(j=0; j<nwindow; j++)
ids[j] = window[j]->id;
qunlock(&all);
qsort(ids, nwindow, sizeof ids[0], idcmp);
dt.name = buf;
for(i=0, j=0; j<nwindow && 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(fs, k, &dt, b+n, x->count-n, clock);
if(len == 0)
break;
if(i >= o)
n += len;
j++;
}
free(ids);
break;
}
t.data = (char*)b;
t.count = n;
filsysrespond(fs, x, &t, nil);
free(b);
return x;
}
static
Xfid*
filsyswrite(Filsys*, Xfid *x, Fid*)
{
sendp(x->c, xfidwrite);
return nil;
}
static
Xfid*
filsysclunk(Filsys *fs, Xfid *x, Fid *f)
{
Fcall t;
if(f->open){
f->busy = FALSE;
f->open = FALSE;
sendp(x->c, xfidclose);
return nil;
}
if(f->w)
sendp(winclosechan, f->w);
f->busy = FALSE;
f->open = FALSE;
return filsysrespond(fs, x, &t, nil);
}
static
Xfid*
filsysremove(Filsys *fs, Xfid *x, Fid*)
{
Fcall t;
return filsysrespond(fs, x, &t, Eperm);
}
static
Xfid*
filsysstat(Filsys *fs, Xfid *x, Fid *f)
{
Fcall t;
t.stat = emalloc(messagesize-IOHDRSZ);
t.nstat = dostat(fs, WIN(x->f->qid), f->dir, t.stat, messagesize-IOHDRSZ, getclock());
x = filsysrespond(fs, x, &t, nil);
free(t.stat);
return x;
}
static
Xfid*
filsyswstat(Filsys *fs, Xfid *x, Fid*)
{
Fcall t;
return filsysrespond(fs, x, &t, Eperm);
}
static
Fid*
newfid(Filsys *fs, int fid)
{
Fid *f, *ff, **fh;
ff = nil;
fh = &fs->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;
}
static
uint
getclock(void)
{
char buf[32];
seek(clockfd, 0, 0);
read(clockfd, buf, sizeof buf);
return atoi(buf);
}
static
int
dostat(Filsys *fs, int id, Dirtab *dir, uchar *buf, int nbuf, uint clock)
{
Dir d;
d.qid.path = QID(id, dir->qid);
if(dir->qid == Qsnarf)
d.qid.vers = snarfversion;
else
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 = fs->user;
d.gid = fs->user;
d.muid = fs->user;
d.atime = clock;
d.mtime = clock;
return convD2M(&d, buf, nbuf);
}