1 // Copyright (C) 2017 The Android Open Source Project 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 16 #ifndef ART_DT_FD_FORWARD_EXPORT_FD_TRANSPORT_H_ 17 #define ART_DT_FD_FORWARD_EXPORT_FD_TRANSPORT_H_ 18 19 #include <stdint.h> 20 21 namespace dt_fd_forward { 22 23 // The file-descriptors sent over a socket to the dt_fd_forward transport. 24 struct FdSet { 25 // A fd that can be read from which provides the JDWP data. 26 int read_fd_; 27 28 // A fd that can be written to in order to provide JDWP responses and events. 29 int write_fd_; 30 31 // A eventfd that can be locked to ensure that writes to write_fd_ are atomic. This must be held 32 // when writing to write_fd_. This allows the proxy to insert packets into the response stream 33 // without having to parse it. 34 int write_lock_fd_; 35 36 static constexpr size_t kDataLength = sizeof(int) * 3; 37 void WriteData(void* buf) { 38 int* ibuf = reinterpret_cast<int*>(buf); 39 ibuf[0] = read_fd_; 40 ibuf[1] = write_fd_; 41 ibuf[2] = write_lock_fd_; 42 } 43 44 static FdSet ReadData(void* buf) { 45 int* ibuf = reinterpret_cast<int*>(buf); 46 return FdSet { ibuf[0], ibuf[1], ibuf[2] }; 47 } 48 }; 49 50 // Sent with the file descriptors if the transport should not skip waiting for the handshake. 51 static constexpr char kPerformHandshakeMessage[] = "HANDSHAKE:REQD"; 52 53 // Sent with the file descriptors if the transport can skip waiting for the handshake. 54 static constexpr char kSkipHandshakeMessage[] = "HANDSHAKE:SKIP"; 55 56 // This message is sent over the fd associated with the transport when we are listening for fds. 57 static constexpr char kListenStartMessage[] = "dt_fd_forward:START-LISTEN"; 58 59 // This message is sent over the fd associated with the transport when we stop listening for fds. 60 static constexpr char kListenEndMessage[] = "dt_fd_forward:END-LISTEN"; 61 62 // This message is sent over the fd associated with the transport when we have accepted a 63 // connection. This is sent before any handshaking has occurred. It is simply an acknowledgment 64 // that the FdSet has been received. This will be paired with a single CLOSING message when these 65 // fds are closed. 66 static constexpr char kAcceptMessage[] = "dt_fd_forward:ACCEPTED"; 67 68 // This message is sent over the fd associated with the transport when we are closing the fds. This 69 // can be used by the proxy to send additional data on a dup'd fd. The write_lock_fd_ will be held 70 // until the other two fds are closed and then it will be released and closed. 71 static constexpr char kCloseMessage[] = "dt_fd_forward:CLOSING"; 72 73 } // namespace dt_fd_forward 74 75 #endif // ART_DT_FD_FORWARD_EXPORT_FD_TRANSPORT_H_ 76
