diff options
Diffstat (limited to 'pkg/flipcall/flipcall_unsafe.go')
| -rw-r--r-- | pkg/flipcall/flipcall_unsafe.go | 87 |
1 files changed, 0 insertions, 87 deletions
diff --git a/pkg/flipcall/flipcall_unsafe.go b/pkg/flipcall/flipcall_unsafe.go deleted file mode 100644 index a37952637..000000000 --- a/pkg/flipcall/flipcall_unsafe.go +++ /dev/null @@ -1,87 +0,0 @@ -// Copyright 2019 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -package flipcall - -import ( - "reflect" - "unsafe" - - "gvisor.dev/gvisor/third_party/gvsync" -) - -// Packets consist of a 16-byte header followed by an arbitrarily-sized -// datagram. The header consists of: -// -// - A 4-byte native-endian connection state. -// -// - A 4-byte native-endian datagram length in bytes. -// -// - 8 reserved bytes. -const ( - // PacketHeaderBytes is the size of a flipcall packet header in bytes. The - // maximum datagram size supported by a flipcall connection is equal to the - // length of the packet window minus PacketHeaderBytes. - // - // PacketHeaderBytes is exported to support its use in constant - // expressions. Non-constant expressions may prefer to use - // PacketWindowLengthForDataCap(). - PacketHeaderBytes = 16 -) - -func (ep *Endpoint) connState() *uint32 { - return (*uint32)((unsafe.Pointer)(ep.packet)) -} - -func (ep *Endpoint) dataLen() *uint32 { - return (*uint32)((unsafe.Pointer)(ep.packet + 4)) -} - -// Data returns the datagram part of ep's packet window as a byte slice. -// -// Note that the packet window is shared with the potentially-untrusted peer -// Endpoint, which may concurrently mutate the contents of the packet window. -// Thus: -// -// - Readers must not assume that two reads of the same byte in Data() will -// return the same result. In other words, readers should read any given byte -// in Data() at most once. -// -// - Writers must not assume that they will read back the same data that they -// have written. In other words, writers should avoid reading from Data() at -// all. -func (ep *Endpoint) Data() []byte { - var bs []byte - bsReflect := (*reflect.SliceHeader)((unsafe.Pointer)(&bs)) - bsReflect.Data = ep.packet + PacketHeaderBytes - bsReflect.Len = int(ep.dataCap) - bsReflect.Cap = int(ep.dataCap) - return bs -} - -// ioSync is a dummy variable used to indicate synchronization to the Go race -// detector. Compare syscall.ioSync. -var ioSync int64 - -func raceBecomeActive() { - if gvsync.RaceEnabled { - gvsync.RaceAcquire((unsafe.Pointer)(&ioSync)) - } -} - -func raceBecomeInactive() { - if gvsync.RaceEnabled { - gvsync.RaceReleaseMerge((unsafe.Pointer)(&ioSync)) - } -} |