moving to scripts

asq-env/lib/python3.9/site-packages/trio/_windows_pipes.py

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+import sys
+from typing import TYPE_CHECKING
+from . import _core
+from ._abc import SendStream, ReceiveStream
+from ._util import ConflictDetector, Final
+from ._core._windows_cffi import _handle, raise_winerror, kernel32, ffi
+
+assert sys.platform == "win32" or not TYPE_CHECKING
+
+# XX TODO: don't just make this up based on nothing.
+DEFAULT_RECEIVE_SIZE = 65536
+
+
+# See the comments on _unix_pipes._FdHolder for discussion of why we set the
+# handle to -1 when it's closed.
+class _HandleHolder:
+    def __init__(self, handle: int) -> None:
+        self.handle = -1
+        if not isinstance(handle, int):
+            raise TypeError("handle must be an int")
+        self.handle = handle
+        _core.register_with_iocp(self.handle)
+
+    @property
+    def closed(self):
+        return self.handle == -1
+
+    def _close(self):
+        if self.closed:
+            return
+        handle = self.handle
+        self.handle = -1
+        if not kernel32.CloseHandle(_handle(handle)):
+            raise_winerror()
+
+    async def aclose(self):
+        self._close()
+        await _core.checkpoint()
+
+    def __del__(self):
+        self._close()
+
+
+class PipeSendStream(SendStream, metaclass=Final):
+    """Represents a send stream over a Windows named pipe that has been
+    opened in OVERLAPPED mode.
+    """
+
+    def __init__(self, handle: int) -> None:
+        self._handle_holder = _HandleHolder(handle)
+        self._conflict_detector = ConflictDetector(
+            "another task is currently using this pipe"
+        )
+
+    async def send_all(self, data: bytes):
+        with self._conflict_detector:
+            if self._handle_holder.closed:
+                raise _core.ClosedResourceError("this pipe is already closed")
+
+            if not data:
+                await _core.checkpoint()
+                return
+
+            try:
+                written = await _core.write_overlapped(self._handle_holder.handle, data)
+            except BrokenPipeError as ex:
+                raise _core.BrokenResourceError from ex
+            # By my reading of MSDN, this assert is guaranteed to pass so long
+            # as the pipe isn't in nonblocking mode, but... let's just
+            # double-check.
+            assert written == len(data)
+
+    async def wait_send_all_might_not_block(self) -> None:
+        with self._conflict_detector:
+            if self._handle_holder.closed:
+                raise _core.ClosedResourceError("This pipe is already closed")
+
+            # not implemented yet, and probably not needed
+            await _core.checkpoint()
+
+    async def aclose(self):
+        await self._handle_holder.aclose()
+
+
+class PipeReceiveStream(ReceiveStream, metaclass=Final):
+    """Represents a receive stream over an os.pipe object."""
+
+    def __init__(self, handle: int) -> None:
+        self._handle_holder = _HandleHolder(handle)
+        self._conflict_detector = ConflictDetector(
+            "another task is currently using this pipe"
+        )
+
+    async def receive_some(self, max_bytes=None) -> bytes:
+        with self._conflict_detector:
+            if self._handle_holder.closed:
+                raise _core.ClosedResourceError("this pipe is already closed")
+
+            if max_bytes is None:
+                max_bytes = DEFAULT_RECEIVE_SIZE
+            else:
+                if not isinstance(max_bytes, int):
+                    raise TypeError("max_bytes must be integer >= 1")
+                if max_bytes < 1:
+                    raise ValueError("max_bytes must be integer >= 1")
+
+            buffer = bytearray(max_bytes)
+            try:
+                size = await _core.readinto_overlapped(
+                    self._handle_holder.handle, buffer
+                )
+            except BrokenPipeError:
+                if self._handle_holder.closed:
+                    raise _core.ClosedResourceError(
+                        "another task closed this pipe"
+                    ) from None
+
+                # Windows raises BrokenPipeError on one end of a pipe
+                # whenever the other end closes, regardless of direction.
+                # Convert this to the Unix behavior of returning EOF to the
+                # reader when the writer closes.
+                #
+                # And since we're not raising an exception, we have to
+                # checkpoint. But readinto_overlapped did raise an exception,
+                # so it might not have checkpointed for us. So we have to
+                # checkpoint manually.
+                await _core.checkpoint()
+                return b""
+            else:
+                del buffer[size:]
+                return buffer
+
+    async def aclose(self):
+        await self._handle_holder.aclose()