fix TUN read pkt

llarp/ev.hpp

@@ -174,11 +174,12 @@ namespace llarp
         asio_evt_pkt* pkt = new asio_evt_pkt;
         pkt->sz           = sz;
         pkt->write        = true;
-        _doserrno = 0;
+        int e             = 0;
         r = WriteFile(fd.tun, data, sz, &x, &pkt->pkt);
         if(r)  // we returned immediately
           return x;
-        else if(_doserrno == ERROR_IO_PENDING)
+        e = GetLastError();
+        if(e == ERROR_IO_PENDING)
           return sz;
         else
           return -1;

llarp/ev_win32.hpp

@@ -139,8 +139,8 @@ namespace llarp
       if(t->before_write)
       {
         t->before_write(t);
+        ev_io::flush_write();
       }
-      ev_io::flush_write();
     }
 
     bool
@@ -397,11 +397,14 @@ struct llarp_win32_loop : public llarp_ev_loop
         llarp::LogWarn("incomplete async io operation: got ", size,
                        " bytes, expected ", pkt->sz, " bytes");*/
       if(!pkt->write)
-        ev->read(readbuf, sizeof(readbuf));
+        ev->read(readbuf, size);
       else
+      {
         ev->flush_write();
+        printf("write tun\n");
+      }
       ++result;
-	  delete pkt;
+      delete pkt;
     }
 
     if(result != -1)

vendor/libtuntap-master/tuntap-windows.c

@@ -399,7 +399,7 @@ tuntap_sys_set_ipv4(struct device *dev, t_tun_in_addr *s, uint32_t mask)
   dns.length   = 4;
   dns.value[0] =
       htonl(0x7F000001); /* apparently this doesn't show in network properties,
-                            but it works 🤷🏻‍♂️ */
+                            but it works */
   dns.value[1] = 0;
 
   ret = DeviceIoControl(dev->tun_fd, TAP_IOCTL_CONFIG_DHCP_SET_OPT, &dns,
@@ -431,7 +431,7 @@ tuntap_read(struct device *dev, void *buf, size_t size)
 {
   DWORD x;
   BOOL r;
-  _doserrno = 0;
+  int e = 0;
   struct asio_evt_pkt *pkt = getTunEventPkt();
   pkt->write               = FALSE;
   pkt->sz                  = size;
@@ -440,8 +440,8 @@ tuntap_read(struct device *dev, void *buf, size_t size)
     r = ReadFile(dev->tun_fd, buf, (DWORD)size, &x, &pkt->pkt);
     if(r)
       return x;
-
-    if(_doserrno && _doserrno != 997)
+    e = GetLastError();
+    if(e && e != 997)
     {
       tuntap_log(TUNTAP_LOG_ERR,
                  (const char *)formated_error(L"%1%0", _doserrno));
@@ -449,8 +449,8 @@ tuntap_read(struct device *dev, void *buf, size_t size)
     }
   }
   else
-    return size;
-  return -1; // unreachable
+    return -1; // unreachable
+  return size;
 }
 
 int
@@ -522,4 +522,4 @@ tuntap_set_ifname(struct device *dev, const char *name)
   tuntap_log(TUNTAP_LOG_NOTICE,
              "Your system does not support tuntap_set_ifname()");
   return -1;
-}
+}