static int do_write(struct empfile *, void *, int, int);
static unsigned get_seqno(struct empfile *, int);
static void new_seqno(struct empfile *, void *);
+static void must_be_fresh(struct empfile *, void *);
static void do_blank(struct empfile *, void *, int, int);
static int ef_check(int);
+static unsigned ef_generation;
+
/*
* Open the file-backed table TYPE (EF_SECTOR, ...).
* HOW are flags to control operation. Naturally, immutable flags are
cachep = ep->cache + (id - ep->baseid) * ep->size;
}
memcpy(into, cachep, ep->size);
+ ef_mark_fresh(type, into);
if (ep->postread)
ep->postread(id, into);
if (ep->onresize && ep->onresize(type) < 0)
return 0;
}
- if (id >= ep->baseid && id < ep->baseid + ep->cids)
+ if (id >= ep->baseid && id < ep->baseid + ep->cids) {
cachep = ep->cache + (id - ep->baseid) * ep->size;
- else
+ if (cachep != from)
+ must_be_fresh(ep, from);
+ } else
cachep = NULL;
if (ep->prewrite)
ep->prewrite(id, cachep, from);
elt->seqno = old_seqno + 1;
}
+void
+ef_make_stale(void)
+{
+ ef_generation++;
+}
+
+void
+ef_mark_fresh(int type, void *buf)
+{
+ struct empfile *ep;
+
+ if (ef_check(type) < 0)
+ return;
+ ep = &empfile[type];
+ if (!(ep->flags & EFF_TYPED))
+ return;
+ ((struct emptypedstr *)buf)->generation = ef_generation;
+}
+
+static void
+must_be_fresh(struct empfile *ep, void *buf)
+{
+ struct emptypedstr *elt = buf;
+
+ if (!(ep->flags & EFF_TYPED))
+ return;
+ CANT_HAPPEN(elt->generation != (ef_generation & 0xfff));
+}
+
/*
* Extend table TYPE by COUNT elements.
* Any pointers obtained from ef_ptr() become invalid.
elt = buf;
elt->seqno = get_seqno(ep, elt->uid);
}
+ ef_mark_fresh(type, buf);
}
/*