>>> I had problem to create a patch - the command didn't finish for long long
>>> time.
>>
>> I created a patch yesterday and it worked fine. It is fairly slow as it
>> diff's all the files you have changed with those on sources.
>>
>> Sadly the 9p protocol is quite badly effected by high (intercontinential)
>> RTTs.
>>
>> -Steve
>
> There were only 2 files in the patch. I wait for about 10 minutes and nothing.
> But then I tried to copy a file from command line.
> If I copied an ordinary file (to /n/sources) it was done immediately.
> But If I copied a file from bind-ed(!) directory it was endless...
> There was no diff, only copy file.
i would guess the problem is a bit different. i'm assuming that
reads from sources work fine. it's not until you try to write there
that there's a problem.
this sounds like a mtu problem. i have a similar problem.
i am not able to submit patches over one particular
network interface. however, if i use a lower mtu, things work fine.
i believe this is because the dumpy dsl modem we have
blocks icmp messages.
you could lower the mtu on the interface, but rather than
punishing all traffic, i wrote a program called cpmtu. cpmtu
is attached. if you define this function
fn cp {cpmtu -m 700 $*}
before you run patch/create, i believe patch should work
properly for you.
as an aside: i don't think 9p itself limits plan 9 performance
over high-latency links. the limitations have more to do with
the number of outstanding messages, which is 1 in the mnt
driver.
- erik
#include <u.h>
#include <libc.h>
int mtu = 8*1024;
int failed;
int gflag;
int uflag;
int xflag;
void copy(char *from, char *to, int todir);
int copy1(int fdf, int fdt, char *from, char *to);
void
usage(void)
{
fprint(2, "usage:\tcp [-gux] [-m mtu] fromfile tofile\n");
fprint(2, "\tcp [-x] [-m mtu] fromfile ... todir\n");
exits("usage");
}
void
main(int argc, char *argv[])
{
Dir *dirb;
int todir, i;
ARGBEGIN {
case 'g':
gflag++;
break;
case 'u':
uflag++;
gflag++;
break;
case 'x':
xflag++;
break;
case 'm':
mtu = atoi(EARGF(usage()));
if(mtu > 0)
break;
default:
usage();
} ARGEND
todir=0;
if(argc < 2)
usage();
dirb = dirstat(argv[argc-1]);
if(dirb!=nil && (dirb->mode&DMDIR))
todir=1;
if(argc>2 && !todir){
fprint(2, "cp: %s not a directory\n", argv[argc-1]);
exits("bad usage");
}
for(i=0; i<argc-1; i++)
copy(argv[i], argv[argc-1], todir);
if(failed)
exits("errors");
exits(0);
}
int
samefile(Dir *a, char *an, char *bn)
{
Dir *b;
int ret;
ret = 0;
b=dirstat(bn);
if(b != nil)
if(b->qid.type==a->qid.type)
if(b->qid.path==a->qid.path)
if(b->qid.vers==a->qid.vers)
if(b->dev==a->dev)
if(b->type==a->type){
fprint(2, "cp: %s and %s are the same file\n", an, bn);
ret = 1;
}
free(b);
return ret;
}
void
copy(char *from, char *to, int todir)
{
Dir *dirb, dirt;
char name[256];
int fdf, fdt, mode;
if(todir){
char *s, *elem;
elem=s=from;
while(*s++)
if(s[-1]=='/')
elem=s;
sprint(name, "%s/%s", to, elem);
to=name;
}
if((dirb=dirstat(from))==nil){
fprint(2,"cp: can't stat %s: %r\n", from);
failed = 1;
return;
}
mode = dirb->mode;
if(mode&DMDIR){
fprint(2, "cp: %s is a directory\n", from);
free(dirb);
failed = 1;
return;
}
if(samefile(dirb, from, to)){
free(dirb);
failed = 1;
return;
}
mode &= 0777;
fdf=open(from, OREAD);
if(fdf<0){
fprint(2, "cp: can't open %s: %r\n", from);
free(dirb);
failed = 1;
return;
}
fdt=create(to, OWRITE, mode);
if(fdt<0){
fprint(2, "cp: can't create %s: %r\n", to);
close(fdf);
free(dirb);
failed = 1;
return;
}
if(copy1(fdf, fdt, from, to)==0 && (xflag || gflag || uflag)){
nulldir(&dirt);
if(xflag){
dirt.mtime = dirb->mtime;
dirt.mode = dirb->mode;
}
if(uflag)
dirt.uid = dirb->uid;
if(gflag)
dirt.gid = dirb->gid;
if(dirfwstat(fdt, &dirt) < 0)
fprint(2, "cp: warning: can't wstat %s: %r\n", to);
}
free(dirb);
close(fdf);
close(fdt);
}
int
copy1(int fdf, int fdt, char *from, char *to)
{
char *buf;
long n, n1, rcount;
int rv;
char err[ERRMAX];
buf = malloc(mtu);
/* clear any residual error */
err[0] = '\0';
errstr(err, ERRMAX);
rv = 0;
for(rcount=0;; rcount++) {
n = read(fdf, buf, mtu);
if(n <= 0)
break;
n1 = write(fdt, buf, n);
if(n1 != n) {
fprint(2, "cp: error writing %s: %r\n", to);
failed = 1;
rv = -1;
break;
}
}
if(n < 0) {
fprint(2, "cp: error reading %s: %r\n", from);
failed = 1;
rv = -1;
}
free(buf);
return rv;
}
