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#include "dat.h"
#include "fns.h"
#include "error.h"
extern Rootdata rootdata[];
extern Dirtab roottab[];
extern int rootmaxq;
static Chan*
rootattach(char *spec)
{
int i;
ulong len;
Rootdata *r;
if(*spec)
error(Ebadspec);
for (i = 0; i < rootmaxq; i++){
r = &rootdata[i];
if (r->sizep){
len = *r->sizep;
r->size = len;
roottab[i].length = len;
}
}
return devattach('/', spec);
}
static int
rootgen(Chan *c, char *name, Dirtab *tab, int nd, int s, Dir *dp)
{
int p, i;
Rootdata *r;
if(s == DEVDOTDOT){
p = rootdata[c->qid.path].dotdot;
c->qid.path = p;
c->qid.type = QTDIR;
name = "#/";
if(p != 0){
for(i = 0; i < rootmaxq; i++)
if(roottab[i].qid.path == c->qid.path){
name = roottab[i].name;
break;
}
}
devdir(c, c->qid, name, 0, eve, 0555, dp);
return 1;
}
if(name != nil){
isdir(c);
r = &rootdata[(int)c->qid.path];
tab = r->ptr;
for(i=0; i<r->size; i++, tab++)
if(strcmp(tab->name, name) == 0){
devdir(c, tab->qid, tab->name, tab->length, eve, tab->perm, dp);
return 1;
}
return -1;
}
if(s >= nd)
return -1;
tab += s;
devdir(c, tab->qid, tab->name, tab->length, eve, tab->perm, dp);
return 1;
}
static Walkqid*
rootwalk(Chan *c, Chan *nc, char **name, int nname)
{
ulong p;
p = c->qid.path;
if(nname == 0)
p = rootdata[p].dotdot;
return devwalk(c, nc, name, nname, rootdata[p].ptr, rootdata[p].size, rootgen);
}
static int
rootstat(Chan *c, uchar *dp, int n)
{
int p;
p = rootdata[c->qid.path].dotdot;
return devstat(c, dp, n, rootdata[p].ptr, rootdata[p].size, rootgen);
}
static Chan*
rootopen(Chan *c, int omode)
{
int p;
p = rootdata[c->qid.path].dotdot;
return devopen(c, omode, rootdata[p].ptr, rootdata[p].size, rootgen);
}
/*
* sysremove() knows this is a nop
*/
static void
rootclose(Chan *c)
{
USED(c);
}
static long
rootread(Chan *c, void *buf, long n, vlong offset)
{
ulong p, len;
uchar *data;
p = c->qid.path;
if(c->qid.type & QTDIR)
return devdirread(c, buf, n, rootdata[p].ptr, rootdata[p].size, rootgen);
len = rootdata[p].size;
if(offset < 0 || offset >= len)
return 0;
if(offset+n > len)
n = len - offset;
data = rootdata[p].ptr;
memmove(buf, data+offset, n);
return n;
}
static long
rootwrite(Chan *c, void *a, long n, vlong off)
{
USED(c); USED(a); USED(n); USED(off);
error(Eperm);
return 0;
}
Dev rootdevtab = {
'/',
"root",
devinit,
rootattach,
rootwalk,
rootstat,
rootopen,
devcreate,
rootclose,
rootread,
devbread,
rootwrite,
devbwrite,
devremove,
devwstat,
};
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