upas/fs: fix more locking bugs, remove debugging clutter, remove planb mbox code

This commit is contained in:
cinap_lenrek 2017-03-14 23:06:39 +01:00
parent 163dccbac0
commit 508b796b27
4 changed files with 66 additions and 614 deletions

View file

@ -173,31 +173,6 @@ sanembmsg(Mailbox *mb, Message *m)
}
}
static void
sanefid(Fid *f)
{
if(f->m == 0)
return;
if(f->mtop){
sanemsg(f->mtop);
assert(f->mtop->refs > 0);
}
sanemsg(f->m);
if(f->m)
if(Topmsg(f->mb, f->m))
assert(f->m->refs > 0);
}
void
sanefids(void)
{
Fid *f;
for(f = fids; f; f = f->next)
if(f->busy)
sanefid(f);
}
static int
Afmt(Fmt *f)
{
@ -427,7 +402,7 @@ main(int argc, char *argv[])
}
if(mboxfile != nil)
if(err = newmbox(mboxfile, "mbox", 0, 0))
if(err = newmbox(mboxfile, "mbox", 0, nil))
sysfatal("opening %s: %s", mboxfile, err);
switch(rfork(RFFDG|RFPROC|RFNAMEG|RFNOTEG|RFREND)){
@ -856,18 +831,19 @@ doclone(Fid *f, int nfid)
return nil;
nf->busy = 1;
nf->open = 0;
if(nf->mb = f->mb)
nf->mb = f->mb;
if(nf->mb){
qlock(nf->mb);
mboxincref(nf->mb);
}
if(nf->m = f->m)
msgincref(gettopmsg(nf->mb, nf->m));
if(nf->mtop = f->mtop){
qlock(nf->mb);
if(nf->mtop = f->mtop)
msgincref(nf->mtop);
nf->qid = f->qid;
if(nf->mb){
qunlock(nf->mb);
}
nf->qid = f->qid;
sanefid(nf);
sanefid(f);
return nf;
}
@ -889,21 +865,18 @@ dowalk(Fid *f, char *name)
{
char *rv, *p;
int t, t1;
Mailbox *omb, *mb;
Mailbox *mb;
Hash *h;
t = FILE(f->qid.path);
rv = Enotexist;
omb = f->mb;
if(omb)
qlock(omb);
else
qlock(&mbllock);
qlock(&mbllock);
if(f->mb)
qlock(f->mb);
/* this must catch everything except . and .. */
retry:
sanefid(f);
t1 = FILE(f->qid.path);
if((t1 == Qmbox || t1 == Qdir) && *name >= 'a' && *name <= 'z'){
h = hlook(f->qid.path, "xxx"); /* sleezy speedup */
@ -915,15 +888,19 @@ sanefid(f);
if(h != nil){
if(f->m)
msgdecref(f->mb, gettopmsg(f->mb, f->m));
if(f->mb && f->mb != h->mb)
if(f->mb && f->mb != h->mb){
qunlock(f->mb);
mboxdecref(f->mb);
}
if(h->mb && h->mb != f->mb)
qlock(h->mb);
f->mb = h->mb;
f->m = h->m;
if(f->m)
msgincref(gettopmsg(f->mb, f->m));
switch(t){
case Qtop:
if(f->mb != nil)
if(f->mb)
mboxincref(f->mb);
break;
case Qmbox:
@ -936,17 +913,16 @@ sanefid(f);
f->qid = h->qid;
if(t1 < Qmax)
f->qid.path = PATH(f->m->id, t1); /* sleezy speedup */
sanefid(f);
rv = nil;
}else if((p = strchr(name, '.')) != nil && *name != '.'){
*p = 0;
goto retry;
}
if(omb)
qunlock(omb);
else
qunlock(&mbllock);
if(f->mb)
qunlock(f->mb);
qunlock(&mbllock);
if(rv == nil)
return rv;
@ -967,9 +943,9 @@ sanefid(f);
f->qid.path = PATH(0, Qtop);
f->qid.type = QTDIR;
f->qid.vers = 0;
qlock(&mbllock);
mb = f->mb;
f->mb = nil;
qlock(&mbllock);
mboxdecref(mb);
qunlock(&mbllock);
break;
@ -1003,7 +979,6 @@ rwalk(Fid *f)
char *rv;
int i;
sanefid(f);
if(f->open)
return Eisopen;
@ -1038,7 +1013,6 @@ sanefid(f);
/* we only error out if no walk */
if(i > 0)
rv = nil;
sanefid(f);
return rv;
}
@ -1056,10 +1030,12 @@ ropen(Fid *f)
/* make sure we've decoded */
if(file == Qbody){
qlock(f->mb);
cachebody(f->mb, f->m);
decode(f->m);
convert(f->m);
putcache(f->mb, f->m);
qunlock(f->mb);
}
rhdr.iounit = 0;
@ -1082,20 +1058,24 @@ readtopdir(Fid*, uchar *buf, long off, int cnt, int blen)
long pos;
Mailbox *mb;
qlock(&mbllock);
n = 0;
pos = 0;
mkstat(&d, nil, nil, Qctl);
m = convD2M(&d, &buf[n], blen);
if(off <= pos){
if(m <= BIT16SZ || m > cnt)
return 0;
goto out;
n += m;
cnt -= m;
}
pos += m;
for(mb = mbl; mb != nil; mb = mb->next){
qlock(mb);
mkstat(&d, mb, nil, Qmbox);
qunlock(mb);
m = convD2M(&d, &buf[n], blen - n);
if(off <= pos){
if(m <= BIT16SZ || m > cnt)
@ -1105,6 +1085,8 @@ readtopdir(Fid*, uchar *buf, long off, int cnt, int blen)
}
pos += m;
}
out:
qlock(&mbllock);
return n;
}
@ -1116,6 +1098,10 @@ readmboxdir(Fid *f, uchar *buf, long off, int cnt, int blen)
long pos;
Message *msg;
qlock(f->mb);
if(off == 0)
syncmbox(f->mb, 1);
n = 0;
if(f->mb->ctl){
mkstat(&d, f->mb, nil, Qmboxctl);
@ -1123,7 +1109,7 @@ readmboxdir(Fid *f, uchar *buf, long off, int cnt, int blen)
if(off == 0){
if(m <= BIT16SZ || m > cnt){
f->fptr = nil;
return 0;
goto out;
}
n += m;
cnt -= m;
@ -1160,7 +1146,8 @@ readmboxdir(Fid *f, uchar *buf, long off, int cnt, int blen)
f->foff = pos;
f->fptr = msg;
f->fvers = f->mb->vers;
out:
qunlock(f->mb);
return n;
}
@ -1172,6 +1159,7 @@ readmsgdir(Fid *f, uchar *buf, long off, int cnt, int blen)
long pos;
Message *msg;
qlock(f->mb);
n = 0;
pos = 0;
for(i = 0; i < Qmax; i++){
@ -1179,7 +1167,7 @@ readmsgdir(Fid *f, uchar *buf, long off, int cnt, int blen)
m = convD2M(&d, &buf[n], blen - n);
if(off <= pos){
if(m <= BIT16SZ || m > cnt)
return n;
goto out;
n += m;
cnt -= m;
}
@ -1196,7 +1184,8 @@ readmsgdir(Fid *f, uchar *buf, long off, int cnt, int blen)
}
pos += m;
}
out:
qunlock(f->mb);
return n;
}
@ -1223,20 +1212,13 @@ rread(Fid *f)
cnt = messagesize - IOHDRSZ;
rhdr.data = (char*)mbuf;
sanefid(f);
t = FILE(f->qid.path);
if(f->qid.type & QTDIR){
if(t == Qtop){
qlock(&mbllock);
if(t == Qtop)
n = readtopdir(f, mbuf, off, cnt, messagesize - IOHDRSZ);
qunlock(&mbllock);
}else if(t == Qmbox) {
qlock(f->mb);
if(off == 0)
syncmbox(f->mb, 1);
else if(t == Qmbox)
n = readmboxdir(f, mbuf, off, cnt, messagesize - IOHDRSZ);
qunlock(f->mb);
}else if(t == Qmboxctl)
else if(t == Qmboxctl)
n = 0;
else
n = readmsgdir(f, mbuf, off, cnt, messagesize - IOHDRSZ);
@ -1318,7 +1300,6 @@ rwrite(Fid *f)
t = FILE(f->qid.path);
rhdr.count = thdr.count;
sanefid(f);
if(thdr.count == 0)
return Ebadctl;
if(thdr.data[thdr.count - 1] == '\n')
@ -1344,7 +1325,7 @@ rwrite(Fid *f)
flags = 0;
if(strcmp(argv[0], "create") == 0)
flags |= DMcreate;
return newmbox(file, argv[2], flags, 0);
return newmbox(file, argv[2], flags, nil);
}
if(strcmp(argv[0], "close") == 0){
if(argc < 2)
@ -1383,10 +1364,8 @@ rwrite(Fid *f)
return Ebadargs;
for(; *argv; argv++){
mboxpathbuf(file, sizeof file, getlog(), *argv);
if(err = newmbox(file, nil, 0, 0))
if(err = newmbox(file, nil, 0, nil))
return err;
// if(!mb->remove)
// return "remove not implemented";
if(err = removembox(file, flags))
return err;
}
@ -1437,23 +1416,22 @@ rclunk(Fid *f)
{
Mailbox *mb;
sanefid(f);
f->busy = 1;
/* coherence(); */
f->fid = -1;
f->open = 0;
mb = f->mb;
if(mb != nil)
if(mb){
qlock(mb);
}
if(f->mtop)
msgdecref(mb, f->mtop);
if(f->m)
msgdecref(mb, gettopmsg(mb, f->m));
f->m = f->mtop = nil;
if(mb != nil){
if(mb){
f->mb = nil;
qunlock(mb);
assert(mb->refs > 0);
qlock(&mbllock);
mboxdecref(mb);
qunlock(&mbllock);
@ -1465,11 +1443,12 @@ sanefid(f);
char *
rremove(Fid *f)
{
sanefid(f);
if(f->m != nil){
if(f->m->deleted == 0)
qlock(f->mb);
if(!f->m->deleted)
mailplumb(f->mb, f->m, 1);
f->m->deleted = Deleted;
qunlock(f->mb);
}
return rclunk(f);
}
@ -1479,15 +1458,15 @@ rstat(Fid *f)
{
Dir d;
sanefid(f);
if(FILE(f->qid.path) == Qmbox){
if(f->mb)
qlock(f->mb);
if(FILE(f->qid.path) == Qmbox)
syncmbox(f->mb, 1);
qunlock(f->mb);
}
mkstat(&d, f->mb, f->m, FILE(f->qid.path));
rhdr.nstat = convD2M(&d, mbuf, messagesize - IOHDRSZ);
rhdr.stat = mbuf;
if(f->mb)
qunlock(f->mb);
return 0;
}
@ -1521,19 +1500,6 @@ newfid(int fid)
return f;
}
int
fidmboxrefs(Mailbox *mb)
{
Fid *f;
int refs = 0;
for(f = fids; f; f = f->next){
if(f->mb == mb)
refs++;
}
return refs;
}
void
io(void)
{
@ -1554,19 +1520,8 @@ io(void)
}
for(;;){
/*
* reading from a pipe or a network device
* will give an error after a few eof reads
* however, we cannot tell the difference
* between a zero-length read and an interrupt
* on the processes writing to us,
* so we wait for the error
*/
checkmboxrefs();
n = read9pmsg(mfd[0], mdata, messagesize);
if(n == 0)
continue;
if(n < 0)
if(n <= 0)
return;
if(convM2S(mdata, n, &thdr) == 0)
continue;
@ -1861,25 +1816,6 @@ hashmboxrefs(Mailbox *mb)
return refs;
}
void
checkmboxrefs(void)
{
int refs;
Mailbox *mb;
// qlock(&mbllock);
for(mb = mbl; mb; mb = mb->next){
qlock(mb);
refs = fidmboxrefs(mb) + 1;
if(refs != mb->refs){
eprint("%s:%s ref mismatch got %d expected %d\n", mb->name, mb->path, refs, mb->refs);
abort();
}
qunlock(mb);
}
// qunlock(&mbllock);
}
void
post(char *name, char *envname, int srvfd)
{

View file

@ -52,7 +52,6 @@ static Mailboxinit *boxinit[] = {
imap4mbox,
pop3mbox,
mdirmbox,
// planbmbox,
plan9mbox,
};
@ -66,7 +65,7 @@ syncmbox(Mailbox *mb, int doplumb)
int n, d, y, a;
Message *m, *next;
assert(canqlock(mb) == 0);
assert(!canqlock(mb));
a = mb->root->subname;
if(rdidxfile(mb, doplumb) == -2)
wridxfile(mb);
@ -116,7 +115,7 @@ mboxrename(char *a, char *b, int flags)
snprint(f1, sizeof f1, "%s", b);
err = newmbox(f0, nil, 0, &mb);
dprint("mboxrename %s %s -> %s\n", f0, f1, err);
if(!err && !mb->rename)
if(err == nil && mb->rename == nil)
err = "rename not supported";
if(err)
goto done;
@ -147,11 +146,9 @@ mboxrename(char *a, char *b, int flags)
henter(PATH(0, Qtop), mb->name,
(Qid){PATH(mb->id, Qmbox), mb->vers, QTDIR}, nil, mb);
done:
if(!mb)
if(mb == nil)
return err;
qunlock(mb);
// if(err)
// mboxdecref(mb);
return err;
}
@ -175,6 +172,8 @@ newmbox(char *path, char *name, int flags, Mailbox **r)
int i;
Mailbox *mb, **l;
if(r)
*r = nil;
initheaders();
mb = emalloc(sizeof *mb);
mb->idxsem = 1;
@ -1146,6 +1145,7 @@ msgincref(Message *m)
void
msgdecref(Mailbox *mb, Message *m)
{
assert(!canqlock(mb));
assert(m->refs > 0);
m->refs--;
if(m->refs == 0){
@ -1202,6 +1202,7 @@ mboxdecref(Mailbox *mb)
qunlock(mb);
}
/* just space over \r. sleezy but necessary for ms email. */
int
deccr(char *x, int len)

View file

@ -14,7 +14,6 @@ OFILES=\
mdir.$O\
mtree.$O\
plan9.$O\
planb.$O\
pop3.$O\
ref.$O\
remove.$O\

View file

@ -1,484 +0,0 @@
/*
* Plan B (mail2fs) mail box format.
*
* BUG: this does not reconstruct the
* raw text for attachments. So imap and others
* will be unable to access any attachment using upas/fs.
* As an aid, we add the path to the message directory
* to the message body, so the user could build the path
* for any attachment and open it.
*/
#include "common.h"
#include <ctype.h>
#include <plumb.h>
#include <libsec.h>
#include "dat.h"
static char*
parseunix(Message *m)
{
char *s, *p, *q;
int l;
Tm tm;
l = m->header - m->start;
m->unixheader = smprint("%.*s", l, m->start);
s = m->start + 5;
if((p = strchr(s, ' ')) == nil)
return s;
*p = 0;
m->unixfrom = strdup(s);
*p++ = ' ';
if(q = strchr(p, '\n'))
*q = 0;
if(strtotm(p, &tm) < 0)
return p;
if(q)
*q = '\n';
m->fileid = (uvlong)tm2sec(&tm) << 8;
return 0;
}
static int
readmessage(Message *m, char *msg)
{
int fd, n;
char *buf, *name, *p;
char hdr[128];
Dir *d;
buf = nil;
d = nil;
name = smprint("%s/raw", msg);
if(name == nil)
return -1;
if(m->filename != nil)
free(m->filename);
m->filename = strdup(name);
if(m->filename == nil)
sysfatal("malloc: %r");
fd = open(name, OREAD);
if(fd < 0)
goto Fail;
n = read(fd, hdr, sizeof(hdr)-1);
if(n <= 0)
goto Fail;
hdr[n] = 0;
close(fd);
fd = -1;
p = strchr(hdr, '\n');
if(p != nil)
*++p = 0;
if(strncmp(hdr, "From ", 5) != 0)
goto Fail;
free(name);
name = smprint("%s/text", msg);
if(name == nil)
goto Fail;
fd = open(name, OREAD);
if(fd < 0)
goto Fail;
d = dirfstat(fd);
if(d == nil)
goto Fail;
buf = malloc(strlen(hdr) + d->length + strlen(msg) + 10); /* few extra chars */
if(buf == nil)
goto Fail;
strcpy(buf, hdr);
p = buf+strlen(hdr);
n = readn(fd, p, d->length);
if(n < 0)
goto Fail;
sprint(p+n, "\n[%s]\n", msg);
n += 2 + strlen(msg) + 2;
close(fd);
free(name);
free(d);
free(m->start);
m->start = buf;
m->lim = m->end = p+n;
if(*(m->end-1) == '\n')
m->end--;
*m->end = 0;
m->bend = m->rbend = m->end;
return 0;
Fail:
if(fd >= 0)
close(fd);
free(name);
free(buf);
free(d);
return -1;
}
/*
* Deleted messages are kept as spam instead.
*/
static void
archive(Message *m)
{
char *dir, *p, *nname;
Dir d;
dir = strdup(m->filename);
nname = nil;
if(dir == nil)
return;
p = strrchr(dir, '/');
if(p == nil)
goto Fail;
*p = 0;
p = strrchr(dir, '/');
if(p == nil)
goto Fail;
p++;
if(*p < '0' || *p > '9')
goto Fail;
nname = smprint("s.%s", p);
if(nname == nil)
goto Fail;
nulldir(&d);
d.name = nname;
dirwstat(dir, &d);
Fail:
free(dir);
free(nname);
}
int
purgembox(Mailbox *mb, int virtual)
{
Message *m, *next;
int newdels;
/* forget about what's no longer in the mailbox */
newdels = 0;
for(m = mb->root->part; m != nil; m = next){
next = m->next;
if(m->deleted > 0 && m->refs == 0){
if(m->inmbox){
newdels++;
/*
* virtual folders are virtual,
* we do not archive
*/
if(virtual == 0)
archive(m);
}
delmessage(mb, m);
}
}
return newdels;
}
static int
mustshow(char* name)
{
if(isdigit(name[0]))
return 1;
if(0 && name[0] == 'a' && name[1] == '.')
return 1;
if(0 && name[0] == 's' && name[1] == '.')
return 1;
return 0;
}
static int
readpbmessage(Mailbox *mb, char *msg, int doplumb, int *nnew)
{
Message *m, **l;
char *x, *p;
m = newmessage(mb->root);
m->mallocd = 1;
m->inmbox = 1;
if(readmessage(m, msg) < 0){
unnewmessage(mb, mb->root, m);
return -1;
}
for(l = &mb->root->part; *l != nil; l = &(*l)->next)
if(strcmp((*l)->filename, m->filename) == 0 &&
*l != m){
if((*l)->deleted < 0)
(*l)->deleted = 0;
delmessage(mb, m);
mb->root->subname--;
return -1;
}
m->header = m->end;
if(x = strchr(m->start, '\n'))
m->header = x + 1;
if(p = parseunix(m))
sysfatal("%s:%s naked From in body? [%s]", mb->path, (*l)->filename, p);
m->mheader = m->mhend = m->header;
parse(mb, m, 0, 0);
if(m != *l && m->deleted != Dup){
logmsg(m, "new");
newcachehash(mb, m, doplumb);
putcache(mb, m);
nnew[0]++;
}
/* chain in */
*l = m;
if(doplumb)
mailplumb(mb, m, 0);
return 0;
}
static int
dcmp(Dir *a, Dir *b)
{
char *an, *bn;
an = a->name;
bn = b->name;
if(an[0] != 0 && an[1] == '.')
an += 2;
if(bn[0] != 0 && bn[1] == '.')
bn += 2;
return strcmp(an, bn);
}
static char*
readpbmbox(Mailbox *mb, int doplumb, int *new)
{
char *month, *msg;
int fd, i, j, nd, nmd;
Dir *d, *md;
static char err[ERRMAX];
fd = open(mb->path, OREAD);
if(fd < 0){
errstr(err, sizeof err);
return err;
}
nd = dirreadall(fd, &d);
close(fd);
if(nd > 0)
qsort(d, nd, sizeof d[0], (int (*)(void*, void*))dcmp);
for(i = 0; i < nd; i++){
month = smprint("%s/%s", mb->path, d[i].name);
if(month == nil)
break;
fd = open(month, OREAD);
if(fd < 0){
fprint(2, "%s: %s: %r\n", argv0, month);
free(month);
continue;
}
md = dirfstat(fd);
if(md != nil && (md->qid.type & QTDIR) != 0){
free(md);
md = nil;
nmd = dirreadall(fd, &md);
for(j = 0; j < nmd; j++)
if(mustshow(md[j].name)){
msg = smprint("%s/%s", month, md[j].name);
readpbmessage(mb, msg, doplumb, new);
free(msg);
}
}
close(fd);
free(month);
free(md);
md = nil;
}
free(d);
return nil;
}
static char*
readpbvmbox(Mailbox *mb, int doplumb, int *new)
{
char *data, *ln, *p, *nln, *msg;
int fd, nr;
long sz;
Dir *d;
static char err[ERRMAX];
fd = open(mb->path, OREAD);
if(fd < 0){
errstr(err, sizeof err);
return err;
}
d = dirfstat(fd);
if(d == nil){
errstr(err, sizeof err);
return err;
}
sz = d->length;
free(d);
if(sz > 2 * 1024 * 1024){
sz = 2 * 1024 * 1024;
fprint(2, "upas/fs: %s: bug: folder too big\n", mb->path);
}
data = malloc(sz+1);
if(data == nil){
errstr(err, sizeof err);
return err;
}
nr = readn(fd, data, sz);
close(fd);
if(nr < 0){
errstr(err, sizeof err);
free(data);
return err;
}
data[nr] = 0;
for(ln = data; *ln != 0; ln = nln){
nln = strchr(ln, '\n');
if(nln != nil)
*nln++ = 0;
else
nln = ln + strlen(ln);
p = strchr(ln , ' ');
if(p != nil)
*p = 0;
p = strchr(ln, '\t');
if(p != nil)
*p = 0;
p = strstr(ln, "/text");
if(p != nil)
*p = 0;
msg = smprint("/mail/box/%s/msgs/%s", user, ln);
if(msg == nil){
fprint(2, "upas/fs: malloc: %r\n");
continue;
}
readpbmessage(mb, msg, doplumb, new);
free(msg);
}
free(data);
return nil;
}
static char*
readmbox(Mailbox *mb, int doplumb, int virt, int *new)
{
char *mberr;
int fd;
Dir *d;
Message *m;
static char err[128];
if(debug)
fprint(2, "read mbox %s\n", mb->path);
fd = open(mb->path, OREAD);
if(fd < 0){
errstr(err, sizeof(err));
return err;
}
d = dirfstat(fd);
if(d == nil){
close(fd);
errstr(err, sizeof(err));
return err;
}
if(mb->d != nil){
if(d->qid.path == mb->d->qid.path &&
d->qid.vers == mb->d->qid.vers){
close(fd);
free(d);
return nil;
}
free(mb->d);
}
close(fd);
mb->d = d;
mb->vers++;
henter(PATH(0, Qtop), mb->name,
(Qid){PATH(mb->id, Qmbox), mb->vers, QTDIR}, nil, mb);
snprint(err, sizeof err, "reading '%s'", mb->path);
logmsg(nil, err, nil);
for(m = mb->root->part; m != nil; m = m->next)
if(m->deleted == 0)
m->deleted = -1;
if(virt == 0)
mberr = readpbmbox(mb, doplumb, new);
else
mberr = readpbvmbox(mb, doplumb, new);
/*
* messages removed from the mbox; flag them to go.
*/
for(m = mb->root->part; m != nil; m = m->next)
if(m->deleted < 0 && doplumb){
delmessage(mb, m);
if(doplumb)
mailplumb(mb, m, 1);
}
logmsg(nil, "mbox read");
return mberr;
}
static char*
mbsync(Mailbox *mb, int doplumb, int *new)
{
char *rv;
rv = readmbox(mb, doplumb, 0, new);
purgembox(mb, 0);
return rv;
}
static char*
mbvsync(Mailbox *mb, int doplumb, int *new)
{
char *rv;
rv = readmbox(mb, doplumb, 1, new);
purgembox(mb, 1);
return rv;
}
char*
planbmbox(Mailbox *mb, char *path)
{
char *list;
static char err[64];
if(access(path, AEXIST) < 0)
return Enotme;
list = smprint("%s/list", path);
if(access(list, AEXIST) < 0){
free(list);
return Enotme;
}
free(list);
mb->sync = mbsync;
if(debug)
fprint(2, "planb mbox %s\n", path);
return nil;
}
char*
planbvmbox(Mailbox *mb, char *path)
{
int fd, nr, i;
char buf[64];
static char err[64];
fd = open(path, OREAD);
if(fd < 0)
return Enotme;
nr = read(fd, buf, sizeof(buf)-1);
close(fd);
if(nr < 7)
return Enotme;
buf[nr] = 0;
for(i = 0; i < 6; i++)
if(buf[i] < '0' || buf[i] > '9')
return Enotme;
if(buf[6] != '/')
return Enotme;
mb->sync = mbvsync;
if(debug)
fprint(2, "planb virtual mbox %s\n", path);
return nil;
}