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#include <u.h>
#include <libc.h>
#include <auth.h>
#include <fcall.h>
#include <thread.h>
#include <9p.h>
static char Ebad[] = "something bad happened";
static char Enomem[] = "no memory";
typedef struct Ramfile Ramfile;
struct Ramfile {
char *data;
int ndata;
};
void
fsread(Req *r)
{
Ramfile *rf;
vlong offset;
long count;
rf = r->fid->file->aux;
offset = r->ifcall.offset;
count = r->ifcall.count;
//print("read %ld %lld\n", *count, offset);
if(offset >= rf->ndata){
r->ofcall.count = 0;
respond(r, nil);
return;
}
if(offset+count >= rf->ndata)
count = rf->ndata - offset;
memmove(r->ofcall.data, rf->data+offset, count);
r->ofcall.count = count;
respond(r, nil);
}
void
fswrite(Req *r)
{
void *v;
Ramfile *rf;
vlong offset;
long count;
rf = r->fid->file->aux;
offset = r->ifcall.offset;
count = r->ifcall.count;
if(offset+count >= rf->ndata){
v = realloc(rf->data, offset+count);
if(v == nil){
respond(r, Enomem);
return;
}
rf->data = v;
rf->ndata = offset+count;
r->fid->file->length = rf->ndata;
}
memmove(rf->data+offset, r->ifcall.data, count);
r->ofcall.count = count;
respond(r, nil);
}
void
fscreate(Req *r)
{
Ramfile *rf;
File *f;
if(f = createfile(r->fid->file, r->ifcall.name, r->fid->uid, r->ifcall.perm, nil)){
rf = emalloc9p(sizeof *rf);
f->aux = rf;
r->fid->file = f;
r->ofcall.qid = f->qid;
respond(r, nil);
return;
}
respond(r, Ebad);
}
void
fsopen(Req *r)
{
Ramfile *rf;
rf = r->fid->file->aux;
if(rf && (r->ifcall.mode&OTRUNC)){
rf->ndata = 0;
r->fid->file->length = 0;
}
respond(r, nil);
}
void
fsdestroyfile(File *f)
{
Ramfile *rf;
//fprint(2, "clunk\n");
rf = f->aux;
if(rf){
free(rf->data);
free(rf);
}
}
Srv fs = {
.open= fsopen,
.read= fsread,
.write= fswrite,
.create= fscreate,
};
void
usage(void)
{
fprint(2, "usage: ramfs [-D] [-s srvname] [-m mtpt]\n");
exits("usage");
}
void
main(int argc, char **argv)
{
char *srvname = nil;
char *mtpt = nil;
Qid q;
fs.tree = alloctree(nil, nil, DMDIR|0777, fsdestroyfile);
q = fs.tree->root->qid;
ARGBEGIN{
case 'D':
chatty9p++;
break;
case 's':
srvname = EARGF(usage());
break;
case 'm':
mtpt = EARGF(usage());
break;
default:
usage();
}ARGEND;
if(argc)
usage();
if(chatty9p)
fprint(2, "ramsrv.nopipe %d srvname %s mtpt %s\n", fs.nopipe, srvname, mtpt);
if(srvname == nil && mtpt == nil)
sysfatal("you should at least specify a -s or -m option");
postmountsrv(&fs, srvname, mtpt, MREPL|MCREATE);
exits(0);
}
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