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#include <u.h>
#include <libc.h>
#include "compat.h"
#include "kbd.h"
#include "error.h"
Snarf snarf = {
.vers = 1
};
enum{
Qdir,
Qcons,
Qconsctl,
Qsnarf,
Qwinname,
};
static Dirtab consdir[]={
".", {Qdir, 0, QTDIR}, 0, DMDIR|0555,
"cons", {Qcons}, 0, 0660,
"consctl", {Qconsctl}, 0, 0220,
"snarf", {Qsnarf}, 0, 0600,
"winname", {Qwinname}, 0, 0000,
};
static Chan*
consattach(char *spec)
{
return devattach('c', spec);
}
static Walkqid*
conswalk(Chan *c, Chan *nc, char **name, int nname)
{
return devwalk(c, nc, name,nname, consdir, nelem(consdir), devgen);
}
static int
consstat(Chan *c, uchar *dp, int n)
{
return devstat(c, dp, n, consdir, nelem(consdir), devgen);
}
static Chan*
consopen(Chan *c, int omode)
{
c->aux = nil;
c = devopen(c, omode, consdir, nelem(consdir), devgen);
switch((ulong)c->qid.path){
case Qconsctl:
break;
case Qsnarf:
if((c->mode&3) == OWRITE || (c->mode&3) == ORDWR)
c->aux = smalloc(sizeof(Snarf));
break;
}
return c;
}
void
setsnarf(char *buf, int n, int *vers)
{
int i;
qlock(&snarf);
snarf.vers++;
if(vers)
*vers = snarf.vers;
for(i = 0; i < nelem(consdir); i++){
if(consdir[i].qid.type == Qsnarf){
consdir[i].qid.vers = snarf.vers;
break;
}
}
free(snarf.buf);
snarf.n = n;
snarf.buf = buf;
qunlock(&snarf);
}
static void
consclose(Chan *c)
{
Snarf *t;
switch((ulong)c->qid.path){
/* last close of control file turns off raw */
case Qconsctl:
break;
/* odd behavior but really ok: replace snarf buffer when /dev/snarf is closed */
case Qsnarf:
t = c->aux;
if(t == nil)
break;
setsnarf(t->buf, t->n, 0);
t->buf = nil; /* setsnarf took it */
free(t);
c->aux = nil;
break;
}
}
static long
consread(Chan *c, void *buf, long n, vlong off)
{
if(n <= 0)
return n;
switch((ulong)c->qid.path){
case Qsnarf:
qlock(&snarf);
if(off < snarf.n){
if(off + n > snarf.n)
n = snarf.n - off;
memmove(buf, snarf.buf+off, n);
}else
n = 0;
qunlock(&snarf);
return n;
case Qdir:
return devdirread(c, buf, n, consdir, nelem(consdir), devgen);
case Qcons:
error(Egreg);
return -1;
default:
print("consread 0x%llux\n", c->qid.path);
error(Egreg);
}
return -1; /* never reached */
}
static long
conswrite(Chan *c, void *va, long n, vlong)
{
Snarf *t;
char *a;
switch((ulong)c->qid.path){
case Qcons:
screenputs(va, n);
break;
case Qconsctl:
error(Egreg);
break;
case Qsnarf:
t = c->aux;
/* always append only */
if(t->n > MAXSNARF) /* avoid thrashing when people cut huge text */
error("snarf buffer too big");
a = realloc(t->buf, t->n + n + 1);
if(a == nil)
error("snarf buffer too big");
t->buf = a;
memmove(t->buf+t->n, va, n);
t->n += n;
t->buf[t->n] = '\0';
break;
default:
print("conswrite: 0x%llux\n", c->qid.path);
error(Egreg);
}
return n;
}
Dev consdevtab = {
'c',
"cons",
devreset,
devinit,
consattach,
conswalk,
consstat,
consopen,
devcreate,
consclose,
consread,
devbread,
conswrite,
devbwrite,
devremove,
devwstat,
};
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