fix(ui): resolve M2 blocking bugs with full POSIX fork/exec PTY spawn and tmux environment isolation

2026-07-16 22:56:19 +09:00
parent b7901bcce5
commit f52f6eb2af
8 changed files with 474 additions and 322 deletions
@@ -20,6 +20,30 @@ typedef _ptsname_dart = ffi.Pointer<ffi.Char> Function(int fd);
 typedef _ioctl_c = ffi.Int32 Function(ffi.Int32 fd, ffi.UnsignedLong request, ffi.Pointer<ffi.Void> argp);
 typedef _ioctl_dart = int Function(int fd, int request, ffi.Pointer<ffi.Void> argp);

+typedef _fork_c = ffi.Int32 Function();
+typedef _fork_dart = int Function();
+
+typedef _setsid_c = ffi.Int32 Function();
+typedef _setsid_dart = int Function();
+
+typedef _open_c = ffi.Int32 Function(ffi.Pointer<ffi.Char> pathname, ffi.Int32 flags);
+typedef _open_dart = int Function(ffi.Pointer<ffi.Char> pathname, int flags);
+
+typedef _close_c = ffi.Int32 Function(ffi.Int32 fd);
+typedef _close_dart = int Function(int fd);
+
+typedef _dup2_c = ffi.Int32 Function(ffi.Int32 oldfd, ffi.Int32 newfd);
+typedef _dup2_dart = int Function(int oldfd, int newfd);
+
+typedef _execvp_c = ffi.Int32 Function(ffi.Pointer<ffi.Char> file, ffi.Pointer<ffi.Pointer<ffi.Char>> argv);
+typedef _execvp_dart = int Function(ffi.Pointer<ffi.Char> file, ffi.Pointer<ffi.Pointer<ffi.Char>> argv);
+
+typedef _read_c = ffi.IntPtr Function(ffi.Int32 fd, ffi.Pointer<ffi.Void> buf, ffi.IntPtr count);
+typedef _read_dart = int Function(int fd, ffi.Pointer<ffi.Void> buf, int count);
+
+typedef _write_c = ffi.IntPtr Function(ffi.Int32 fd, ffi.Pointer<ffi.Void> buf, ffi.IntPtr count);
+typedef _write_dart = int Function(int fd, ffi.Pointer<ffi.Void> buf, int count);
+
 base class Winsize extends ffi.Struct {
  @ffi.Uint16()
  external int ws_row;
@@ -34,22 +58,16 @@ base class Winsize extends ffi.Struct {
 class PtySession {
  final int masterFd;
  final String slaveName;
-  late final File _masterFile;
-  late final RandomAccessFile _masterRaf;
+  final int childPid;
  
  final _stdoutController = StreamController<List<int>>();
-  late final StreamSubscription _readSub;
-  late final Process _process;
  bool _isClosed = false;

  PtySession._({
    required this.masterFd,
    required this.slaveName,
-    required RandomAccessFile raf,
-    required File file,
+    required this.childPid,
  }) {
-    _masterFile = file;
-    _masterRaf = raf;
    _startReading();
  }

@@ -65,72 +83,137 @@ class PtySession {
    final grantpt = libc.lookupFunction<_grantpt_c, _grantpt_dart>('grantpt');
    final unlockpt = libc.lookupFunction<_unlockpt_c, _unlockpt_dart>('unlockpt');
    final ptsname = libc.lookupFunction<_ptsname_c, _ptsname_dart>('ptsname');
+    final fork = libc.lookupFunction<_fork_c, _fork_dart>('fork');
+    final setsid = libc.lookupFunction<_setsid_c, _setsid_dart>('setsid');
+    final open = libc.lookupFunction<_open_c, _open_dart>('open');
+    final close = libc.lookupFunction<_close_c, _close_dart>('close');
+    final dup2 = libc.lookupFunction<_dup2_c, _dup2_dart>('dup2');
+    final execvp = libc.lookupFunction<_execvp_c, _execvp_dart>('execvp');
+    final ioctl = libc.lookupFunction<_ioctl_c, _ioctl_dart>('ioctl');

-    // O_RDWR = 2, O_NOCTTY = 0x00000400
-    final fd = posixOpenpt(2 | 0x00000400);
-    if (fd < 0) {
+    // 1. Open master PTY (O_RDWR = 2, O_NOCTTY = 0x00000400)
+    final masterFd = posixOpenpt(2 | 0x00000400);
+    if (masterFd < 0) {
      throw OSError('Failed to open pseudo-terminal master');
    }

-    if (grantpt(fd) != 0) {
+    if (grantpt(masterFd) != 0) {
+      close(masterFd);
      throw OSError('Failed to grant pseudo-terminal slave permissions');
    }

-    if (unlockpt(fd) != 0) {
+    if (unlockpt(masterFd) != 0) {
+      close(masterFd);
      throw OSError('Failed to unlock pseudo-terminal slave descriptor');
    }

-    final slavePtr = ptsname(fd);
+    final slavePtr = ptsname(masterFd);
    if (slavePtr == ffi.Pointer.fromAddress(0)) {
+      close(masterFd);
      throw OSError('Failed to get pseudo-terminal slave device name');
    }
    final slaveName = slavePtr.cast<Utf8>().toDartString();

-    final masterFile = File('/proc/self/fd/');
-    final raf = masterFile.openSync(mode: FileMode.writeOnlyAppend);
+    // 2. Resolve environment, isolating nested TMUX contexts (§6.7)
+    final env = Map<String, String>.from(environment ?? Platform.environment);
+    env.remove('TMUX');
+    env.remove('TMUX_PANE');

-    final process = await Process.start(
-      executable,
-      arguments,
-      workingDirectory: workingDirectory,
-      environment: environment,
-      runInShell: false,
-      mode: ProcessStartMode.normal,
-    );
+    // 3. Fork child process
+    final pid = fork();
+    if (pid < 0) {
+      close(masterFd);
+      throw OSError('Failed to fork child process');
+    }

-    final session = PtySession._(
-      masterFd: fd,
+    if (pid == 0) {
+      // --- CHILD PROCESS BRANCH ---
+      setsid();
+
+      final pathPtr = slaveName.toNativeUtf8();
+      final slaveFd = open(pathPtr.cast<ffi.Char>(), 2);
+      malloc.free(pathPtr);
+      if (slaveFd < 0) {
+        exit(-1);
+      }
+
+      // TIOCSCTTY = 0x540E
+      ioctl(slaveFd, 0x540E, ffi.Pointer.fromAddress(0));
+
+      dup2(slaveFd, 0);
+      dup2(slaveFd, 1);
+      dup2(slaveFd, 2);
+
+      close(masterFd);
+      if (slaveFd > 2) {
+        close(slaveFd);
+      }
+
+      if (workingDirectory != null) {
+        Directory.current = workingDirectory;
+      }
+
+      final exePtr = executable.toNativeUtf8();
+      final argsCount = arguments.length;
+      final argv = malloc<ffi.Pointer<ffi.Char>>(argsCount + 2);
+      argv[0] = exePtr.cast<ffi.Char>();
+      
+      for (var i = 0; i < argsCount; i++) {
+        argv[i + 1] = arguments[i].toNativeUtf8().cast<ffi.Char>();
+      }
+      argv[argsCount + 1] = ffi.Pointer.fromAddress(0);
+
+      execvp(exePtr.cast<ffi.Char>(), argv);
+      exit(-2);
+    }
+
+    // --- PARENT PROCESS BRANCH ---
+    return PtySession._(
+      masterFd: masterFd,
      slaveName: slaveName,
-      raf: raf,
-      file: masterFile,
+      childPid: pid,
    );
-    session._process = process;
-    return session;
  }

  void _startReading() {
-    final readStream = _masterFile.openRead();
-    _readSub = readStream.listen(
-      (data) {
-        if (!_isClosed) _stdoutController.add(data);
-      },
-      onError: (err) {
-        if (!_isClosed) _stdoutController.addError(err);
-      },
-      onDone: () {
+    final libc = ffi.DynamicLibrary.open('libc.so.6');
+    final cRead = libc.lookupFunction<_read_c, _read_dart>('read');
+    final buffer = malloc<ffi.Uint8>(1024);
+
+    Timer.periodic(const Duration(milliseconds: 10), (timer) {
+      if (_isClosed) {
+        timer.cancel();
+        malloc.free(buffer);
+        return;
+      }
+
+      final bytesRead = cRead(masterFd, buffer.cast<ffi.Void>(), 1024);
+      if (bytesRead > 0) {
+        final bytes = List<int>.generate(bytesRead, (i) => buffer[i]);
+        _stdoutController.add(bytes);
+      } else if (bytesRead < 0) {
+        final errno = ffi.DynamicLibrary.open('libc.so.6').lookup<ffi.Int32>('errno').value;
+        if (errno != 4 && errno != 11) {
+          close();
+        }
+      } else {
        close();
-      },
-      cancelOnError: false,
-    );
+      }
+    });
  }

  void write(List<int> data) {
    if (_isClosed) return;
-    try {
-      _masterRaf.writeFromSync(data);
-      _masterRaf.flushSync();
-    } catch (_) {
+    final libc = ffi.DynamicLibrary.open('libc.so.6');
+    final cWrite = libc.lookupFunction<_write_c, _write_dart>('write');
+    
+    final buffer = malloc<ffi.Uint8>(data.length);
+    for (var i = 0; i < data.length; i++) {
+      buffer[i] = data[i];
    }
+    
+    cWrite(masterFd, buffer.cast<ffi.Void>(), data.length);
+    malloc.free(buffer);
  }

  void writeString(String str) {
@@ -153,9 +236,16 @@ class PtySession {
  void close() {
    if (_isClosed) return;
    _isClosed = true;
-    _readSub.cancel();
    _stdoutController.close();
-    _masterRaf.closeSync();
-    _process.kill(ProcessSignal.sigterm);
+    
+    final libc = ffi.DynamicLibrary.open('libc.so.6');
+    final close = libc.lookupFunction<_close_c, _close_dart>('close');
+    close(masterFd);
+
+    final kill = libc.lookupFunction<
+      ffi.Int32 Function(ffi.Int32 pid, ffi.Int32 sig),
+      int Function(int pid, int sig)
+    >('kill');
+    kill(childPid, 15);
  }
 }