diff third_party/libuv/src/win/pipe.c @ 160:948de3f54cea

[ThirdParty] Added libuv
author June Park <parkjune1995@gmail.com>
date Wed, 14 Jan 2026 19:39:52 -0800
parents
children
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/third_party/libuv/src/win/pipe.c	Wed Jan 14 19:39:52 2026 -0800
@@ -0,0 +1,2725 @@
+/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include <assert.h>
+#include <io.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "handle-inl.h"
+#include "internal.h"
+#include "req-inl.h"
+#include "stream-inl.h"
+#include "uv-common.h"
+#include "uv.h"
+
+#include <aclapi.h>
+#include <accctrl.h>
+
+/* A zero-size buffer for use by uv_pipe_read */
+static char uv_zero_[] = "";
+
+/* Null uv_buf_t */
+static const uv_buf_t uv_null_buf_ = { 0, NULL };
+
+/* The timeout that the pipe will wait for the remote end to write data when
+ * the local ends wants to shut it down. */
+static const int64_t eof_timeout = 50; /* ms */
+
+static const int default_pending_pipe_instances = 4;
+
+/* Pipe prefix */
+static char pipe_prefix[] = "\\\\?\\pipe";
+static const size_t pipe_prefix_len = sizeof(pipe_prefix) - 1;
+
+/* IPC incoming xfer queue item. */
+typedef struct {
+  uv__ipc_socket_xfer_type_t xfer_type;
+  uv__ipc_socket_xfer_info_t xfer_info;
+  struct uv__queue member;
+} uv__ipc_xfer_queue_item_t;
+
+/* IPC frame header flags. */
+/* clang-format off */
+enum {
+  UV__IPC_FRAME_HAS_DATA                = 0x01,
+  UV__IPC_FRAME_HAS_SOCKET_XFER         = 0x02,
+  UV__IPC_FRAME_XFER_IS_TCP_CONNECTION  = 0x04,
+  /* These are combinations of the flags above. */
+  UV__IPC_FRAME_XFER_FLAGS              = 0x06,
+  UV__IPC_FRAME_VALID_FLAGS             = 0x07
+};
+/* clang-format on */
+
+/* IPC frame header. */
+typedef struct {
+  uint32_t flags;
+  uint32_t reserved1;   /* Ignored. */
+  uint32_t data_length; /* Must be zero if there is no data. */
+  uint32_t reserved2;   /* Must be zero. */
+} uv__ipc_frame_header_t;
+
+/* To implement the IPC protocol correctly, these structures must have exactly
+ * the right size. */
+STATIC_ASSERT(sizeof(uv__ipc_frame_header_t) == 16);
+STATIC_ASSERT(sizeof(uv__ipc_socket_xfer_info_t) == 632);
+
+/* Coalesced write request. */
+typedef struct {
+  uv_write_t req;       /* Internal heap-allocated write request. */
+  uv_write_t* user_req; /* Pointer to user-specified uv_write_t. */
+} uv__coalesced_write_t;
+
+
+static void eof_timer_init(uv_pipe_t* pipe);
+static void eof_timer_start(uv_pipe_t* pipe);
+static void eof_timer_stop(uv_pipe_t* pipe);
+static void eof_timer_cb(uv_timer_t* timer);
+static void eof_timer_destroy(uv_pipe_t* pipe);
+static void eof_timer_close_cb(uv_handle_t* handle);
+
+
+/* Does the file path contain embedded nul bytes? */
+static int includes_nul(const char *s, size_t n) {
+  if (n == 0)
+    return 0;
+  return NULL != memchr(s, '\0', n);
+}
+
+
+static void uv__unique_pipe_name(unsigned long long ptr, char* name, size_t size) {
+  snprintf(name, size, "\\\\?\\pipe\\uv\\%llu-%lu", ptr, GetCurrentProcessId());
+}
+
+
+int uv_pipe_init(uv_loop_t* loop, uv_pipe_t* handle, int ipc) {
+  uv__stream_init(loop, (uv_stream_t*)handle, UV_NAMED_PIPE);
+
+  handle->reqs_pending = 0;
+  handle->handle = INVALID_HANDLE_VALUE;
+  handle->name = NULL;
+  handle->pipe.conn.ipc_remote_pid = 0;
+  handle->pipe.conn.ipc_data_frame.payload_remaining = 0;
+  uv__queue_init(&handle->pipe.conn.ipc_xfer_queue);
+  handle->pipe.conn.ipc_xfer_queue_length = 0;
+  handle->ipc = ipc;
+  handle->pipe.conn.non_overlapped_writes_tail = NULL;
+
+  return 0;
+}
+
+
+static void uv__pipe_connection_init(uv_pipe_t* handle) {
+  assert(!(handle->flags & UV_HANDLE_PIPESERVER));
+  uv__connection_init((uv_stream_t*) handle);
+  handle->read_req.data = handle;
+  handle->pipe.conn.eof_timer = NULL;
+}
+
+
+static HANDLE open_named_pipe(const WCHAR* name, DWORD* duplex_flags) {
+  HANDLE pipeHandle;
+
+  /*
+   * Assume that we have a duplex pipe first, so attempt to
+   * connect with GENERIC_READ | GENERIC_WRITE.
+   */
+  pipeHandle = CreateFileW(name,
+                           GENERIC_READ | GENERIC_WRITE,
+                           0,
+                           NULL,
+                           OPEN_EXISTING,
+                           FILE_FLAG_OVERLAPPED,
+                           NULL);
+  if (pipeHandle != INVALID_HANDLE_VALUE) {
+    *duplex_flags = UV_HANDLE_READABLE | UV_HANDLE_WRITABLE;
+    return pipeHandle;
+  }
+
+  /*
+   * If the pipe is not duplex CreateFileW fails with
+   * ERROR_ACCESS_DENIED.  In that case try to connect
+   * as a read-only or write-only.
+   */
+  if (GetLastError() == ERROR_ACCESS_DENIED) {
+    pipeHandle = CreateFileW(name,
+                             GENERIC_READ | FILE_WRITE_ATTRIBUTES,
+                             0,
+                             NULL,
+                             OPEN_EXISTING,
+                             FILE_FLAG_OVERLAPPED,
+                             NULL);
+
+    if (pipeHandle != INVALID_HANDLE_VALUE) {
+      *duplex_flags = UV_HANDLE_READABLE;
+      return pipeHandle;
+    }
+  }
+
+  if (GetLastError() == ERROR_ACCESS_DENIED) {
+    pipeHandle = CreateFileW(name,
+                             GENERIC_WRITE | FILE_READ_ATTRIBUTES,
+                             0,
+                             NULL,
+                             OPEN_EXISTING,
+                             FILE_FLAG_OVERLAPPED,
+                             NULL);
+
+    if (pipeHandle != INVALID_HANDLE_VALUE) {
+      *duplex_flags = UV_HANDLE_WRITABLE;
+      return pipeHandle;
+    }
+  }
+
+  return INVALID_HANDLE_VALUE;
+}
+
+
+static void close_pipe(uv_pipe_t* pipe) {
+  assert(pipe->u.fd == -1 || pipe->u.fd > 2);
+  if (pipe->u.fd == -1)
+    CloseHandle(pipe->handle);
+  else
+    _close(pipe->u.fd);
+
+  pipe->u.fd = -1;
+  pipe->handle = INVALID_HANDLE_VALUE;
+}
+
+
+static int uv__pipe_server(
+    HANDLE* pipeHandle_ptr, DWORD access,
+    char* name, size_t nameSize, unsigned long long random) {
+  HANDLE pipeHandle;
+  int err;
+
+  for (;;) {
+    uv__unique_pipe_name(random, name, nameSize);
+
+    pipeHandle = CreateNamedPipeA(name,
+      access | FILE_FLAG_FIRST_PIPE_INSTANCE,
+      PIPE_TYPE_BYTE | PIPE_READMODE_BYTE | PIPE_WAIT, 1, 65536, 65536, 0,
+      NULL);
+
+    if (pipeHandle != INVALID_HANDLE_VALUE) {
+      /* No name collisions.  We're done. */
+      break;
+    }
+
+    err = GetLastError();
+    if (err != ERROR_PIPE_BUSY && err != ERROR_ACCESS_DENIED) {
+      goto error;
+    }
+
+    /* Pipe name collision.  Increment the random number and try again. */
+    random++;
+  }
+
+  *pipeHandle_ptr = pipeHandle;
+
+  return 0;
+
+ error:
+  if (pipeHandle != INVALID_HANDLE_VALUE)
+    CloseHandle(pipeHandle);
+
+  return err;
+}
+
+
+static int uv__create_pipe_pair(
+    HANDLE* server_pipe_ptr, HANDLE* client_pipe_ptr,
+    unsigned int server_flags, unsigned int client_flags,
+    int inherit_client, unsigned long long random) {
+  /* allowed flags are: UV_READABLE_PIPE | UV_WRITABLE_PIPE | UV_NONBLOCK_PIPE */
+  char pipe_name[64];
+  SECURITY_ATTRIBUTES sa;
+  DWORD server_access;
+  DWORD client_access;
+  HANDLE server_pipe;
+  HANDLE client_pipe;
+  int err;
+
+  server_pipe = INVALID_HANDLE_VALUE;
+  client_pipe = INVALID_HANDLE_VALUE;
+
+  server_access = 0;
+  if (server_flags & UV_READABLE_PIPE)
+    server_access |= PIPE_ACCESS_INBOUND;
+  if (server_flags & UV_WRITABLE_PIPE)
+    server_access |= PIPE_ACCESS_OUTBOUND;
+  if (server_flags & UV_NONBLOCK_PIPE)
+    server_access |= FILE_FLAG_OVERLAPPED;
+  server_access |= WRITE_DAC;
+
+  client_access = 0;
+  if (client_flags & UV_READABLE_PIPE)
+    client_access |= GENERIC_READ;
+  else
+    client_access |= FILE_READ_ATTRIBUTES;
+  if (client_flags & UV_WRITABLE_PIPE)
+    client_access |= GENERIC_WRITE;
+  else
+    client_access |= FILE_WRITE_ATTRIBUTES;
+  client_access |= WRITE_DAC;
+
+  /* Create server pipe handle. */
+  err = uv__pipe_server(&server_pipe,
+                        server_access,
+                        pipe_name,
+                        sizeof(pipe_name),
+                        random);
+  if (err)
+    goto error;
+
+  /* Create client pipe handle. */
+  sa.nLength = sizeof sa;
+  sa.lpSecurityDescriptor = NULL;
+  sa.bInheritHandle = inherit_client;
+
+  client_pipe = CreateFileA(pipe_name,
+                            client_access,
+                            0,
+                            &sa,
+                            OPEN_EXISTING,
+                            (client_flags & UV_NONBLOCK_PIPE) ? FILE_FLAG_OVERLAPPED : 0,
+                            NULL);
+  if (client_pipe == INVALID_HANDLE_VALUE) {
+    err = GetLastError();
+    goto error;
+  }
+
+#ifndef NDEBUG
+  /* Validate that the pipe was opened in the right mode. */
+  {
+    DWORD mode;
+    BOOL r;
+    r = GetNamedPipeHandleState(client_pipe, &mode, NULL, NULL, NULL, NULL, 0);
+    if (r == TRUE) {
+      assert(mode == (PIPE_READMODE_BYTE | PIPE_WAIT));
+    } else {
+      fprintf(stderr, "libuv assertion failure: GetNamedPipeHandleState failed\n");
+    }
+  }
+#endif
+
+  /* Do a blocking ConnectNamedPipe.  This should not block because we have
+   * both ends of the pipe created. */
+  if (!ConnectNamedPipe(server_pipe, NULL)) {
+    if (GetLastError() != ERROR_PIPE_CONNECTED) {
+      err = GetLastError();
+      goto error;
+    }
+  }
+
+  *client_pipe_ptr = client_pipe;
+  *server_pipe_ptr = server_pipe;
+  return 0;
+
+ error:
+  if (server_pipe != INVALID_HANDLE_VALUE)
+    CloseHandle(server_pipe);
+
+  if (client_pipe != INVALID_HANDLE_VALUE)
+    CloseHandle(client_pipe);
+
+  return err;
+}
+
+
+int uv_pipe(uv_file fds[2], int read_flags, int write_flags) {
+  uv_file temp[2];
+  int err;
+  HANDLE readh;
+  HANDLE writeh;
+
+  /* Make the server side the inbound (read) end, */
+  /* so that both ends will have FILE_READ_ATTRIBUTES permission. */
+  /* TODO: better source of local randomness than &fds? */
+  read_flags |= UV_READABLE_PIPE;
+  write_flags |= UV_WRITABLE_PIPE;
+  err = uv__create_pipe_pair(&readh,
+                             &writeh,
+                             read_flags,
+                             write_flags,
+                             0,
+                             (uintptr_t) &fds[0]);
+  if (err != 0)
+    return err;
+  temp[0] = _open_osfhandle((intptr_t) readh, 0);
+  if (temp[0] == -1) {
+    if (errno == UV_EMFILE)
+      err = UV_EMFILE;
+    else
+      err = UV_UNKNOWN;
+    CloseHandle(readh);
+    CloseHandle(writeh);
+    return err;
+  }
+  temp[1] = _open_osfhandle((intptr_t) writeh, 0);
+  if (temp[1] == -1) {
+    if (errno == UV_EMFILE)
+      err = UV_EMFILE;
+    else
+      err = UV_UNKNOWN;
+    _close(temp[0]);
+    CloseHandle(writeh);
+    return err;
+  }
+  fds[0] = temp[0];
+  fds[1] = temp[1];
+  return 0;
+}
+
+
+int uv__create_stdio_pipe_pair(uv_loop_t* loop,
+    uv_pipe_t* parent_pipe, HANDLE* child_pipe_ptr, unsigned int flags) {
+  /* The parent_pipe is always the server_pipe and kept by libuv.
+   * The child_pipe is always the client_pipe and is passed to the child.
+   * The flags are specified with respect to their usage in the child. */
+  HANDLE server_pipe;
+  HANDLE client_pipe;
+  unsigned int server_flags;
+  unsigned int client_flags;
+  int err;
+
+  uv__pipe_connection_init(parent_pipe);
+
+  server_pipe = INVALID_HANDLE_VALUE;
+  client_pipe = INVALID_HANDLE_VALUE;
+
+  server_flags = 0;
+  client_flags = 0;
+  if (flags & UV_READABLE_PIPE) {
+    /* The server needs inbound (read) access too, otherwise CreateNamedPipe()
+     * won't give us the FILE_READ_ATTRIBUTES permission. We need that to probe
+     * the state of the write buffer when we're trying to shutdown the pipe. */
+    server_flags |= UV_READABLE_PIPE | UV_WRITABLE_PIPE;
+    client_flags |= UV_READABLE_PIPE;
+  }
+  if (flags & UV_WRITABLE_PIPE) {
+    server_flags |= UV_READABLE_PIPE;
+    client_flags |= UV_WRITABLE_PIPE;
+  }
+  server_flags |= UV_NONBLOCK_PIPE;
+  if (flags & UV_NONBLOCK_PIPE || parent_pipe->ipc) {
+    client_flags |= UV_NONBLOCK_PIPE;
+  }
+
+  err = uv__create_pipe_pair(&server_pipe, &client_pipe,
+          server_flags, client_flags, 1, (uintptr_t) server_pipe);
+  if (err)
+    goto error;
+
+  if (CreateIoCompletionPort(server_pipe,
+                             loop->iocp,
+                             (ULONG_PTR) parent_pipe,
+                             0) == NULL) {
+    err = GetLastError();
+    goto error;
+  }
+
+  parent_pipe->handle = server_pipe;
+  *child_pipe_ptr = client_pipe;
+
+  /* The server end is now readable and/or writable. */
+  if (flags & UV_READABLE_PIPE)
+    parent_pipe->flags |= UV_HANDLE_WRITABLE;
+  if (flags & UV_WRITABLE_PIPE)
+    parent_pipe->flags |= UV_HANDLE_READABLE;
+
+  return 0;
+
+ error:
+  if (server_pipe != INVALID_HANDLE_VALUE)
+    CloseHandle(server_pipe);
+
+  if (client_pipe != INVALID_HANDLE_VALUE)
+    CloseHandle(client_pipe);
+
+  return err;
+}
+
+
+static int uv__set_pipe_handle(uv_loop_t* loop,
+                               uv_pipe_t* handle,
+                               HANDLE pipeHandle,
+                               int fd,
+                               DWORD duplex_flags) {
+  NTSTATUS nt_status;
+  IO_STATUS_BLOCK io_status;
+  FILE_MODE_INFORMATION mode_info;
+  DWORD mode = PIPE_READMODE_BYTE | PIPE_WAIT;
+  DWORD current_mode = 0;
+  DWORD err = 0;
+
+  assert(handle->flags & UV_HANDLE_CONNECTION);
+  assert(!(handle->flags & UV_HANDLE_PIPESERVER));
+  if (handle->flags & UV_HANDLE_CLOSING)
+    return UV_EINVAL;
+  if (handle->handle != INVALID_HANDLE_VALUE)
+    return UV_EBUSY;
+
+  if (!SetNamedPipeHandleState(pipeHandle, &mode, NULL, NULL)) {
+    err = GetLastError();
+    if (err == ERROR_ACCESS_DENIED) {
+      /*
+       * SetNamedPipeHandleState can fail if the handle doesn't have either
+       * GENERIC_WRITE  or FILE_WRITE_ATTRIBUTES.
+       * But if the handle already has the desired wait and blocking modes
+       * we can continue.
+       */
+      if (!GetNamedPipeHandleState(pipeHandle, &current_mode, NULL, NULL,
+                                   NULL, NULL, 0)) {
+        return uv_translate_sys_error(GetLastError());
+      } else if (current_mode & PIPE_NOWAIT) {
+        return UV_EACCES;
+      }
+    } else {
+      /* If this returns ERROR_INVALID_PARAMETER we probably opened
+       * something that is not a pipe. */
+      if (err == ERROR_INVALID_PARAMETER) {
+        return UV_ENOTSOCK;
+      }
+      return uv_translate_sys_error(err);
+    }
+  }
+
+  /* Check if the pipe was created with FILE_FLAG_OVERLAPPED. */
+  nt_status = pNtQueryInformationFile(pipeHandle,
+                                      &io_status,
+                                      &mode_info,
+                                      sizeof(mode_info),
+                                      FileModeInformation);
+  if (nt_status != STATUS_SUCCESS) {
+    return uv_translate_sys_error(err);
+  }
+
+  if (mode_info.Mode & FILE_SYNCHRONOUS_IO_ALERT ||
+      mode_info.Mode & FILE_SYNCHRONOUS_IO_NONALERT) {
+    /* Non-overlapped pipe. */
+    handle->flags |= UV_HANDLE_NON_OVERLAPPED_PIPE;
+    handle->pipe.conn.readfile_thread_handle = NULL;
+    InitializeCriticalSection(&handle->pipe.conn.readfile_thread_lock);
+  } else {
+    /* Overlapped pipe.  Try to associate with IOCP. */
+    if (CreateIoCompletionPort(pipeHandle,
+                               loop->iocp,
+                               (ULONG_PTR) handle,
+                               0) == NULL) {
+      handle->flags |= UV_HANDLE_EMULATE_IOCP;
+    }
+  }
+
+  handle->handle = pipeHandle;
+  handle->u.fd = fd;
+  handle->flags |= duplex_flags;
+
+  return 0;
+}
+
+
+static int pipe_alloc_accept(uv_loop_t* loop, uv_pipe_t* handle,
+                             uv_pipe_accept_t* req, BOOL firstInstance) {
+  assert(req->pipeHandle == INVALID_HANDLE_VALUE);
+
+  req->pipeHandle =
+      CreateNamedPipeW(handle->name,
+                       PIPE_ACCESS_DUPLEX | FILE_FLAG_OVERLAPPED | WRITE_DAC |
+                         (firstInstance ? FILE_FLAG_FIRST_PIPE_INSTANCE : 0),
+                       PIPE_TYPE_BYTE | PIPE_READMODE_BYTE | PIPE_WAIT,
+                       PIPE_UNLIMITED_INSTANCES, 65536, 65536, 0, NULL);
+
+  if (req->pipeHandle == INVALID_HANDLE_VALUE) {
+    return 0;
+  }
+
+  /* Associate it with IOCP so we can get events. */
+  if (CreateIoCompletionPort(req->pipeHandle,
+                             loop->iocp,
+                             (ULONG_PTR) handle,
+                             0) == NULL) {
+    uv_fatal_error(GetLastError(), "CreateIoCompletionPort");
+  }
+
+  /* Stash a handle in the server object for use from places such as
+   * getsockname and chmod. As we transfer ownership of these to client
+   * objects, we'll allocate new ones here. */
+  handle->handle = req->pipeHandle;
+
+  return 1;
+}
+
+
+static DWORD WINAPI pipe_shutdown_thread_proc(void* parameter) {
+  uv_loop_t* loop;
+  uv_pipe_t* handle;
+  uv_shutdown_t* req;
+
+  req = (uv_shutdown_t*) parameter;
+  assert(req);
+  handle = (uv_pipe_t*) req->handle;
+  assert(handle);
+  loop = handle->loop;
+  assert(loop);
+
+  FlushFileBuffers(handle->handle);
+
+  /* Post completed */
+  POST_COMPLETION_FOR_REQ(loop, req);
+
+  return 0;
+}
+
+
+void uv__pipe_shutdown(uv_loop_t* loop, uv_pipe_t* handle, uv_shutdown_t *req) {
+  DWORD result;
+  NTSTATUS nt_status;
+  IO_STATUS_BLOCK io_status;
+  FILE_PIPE_LOCAL_INFORMATION pipe_info;
+
+  assert(handle->flags & UV_HANDLE_CONNECTION);
+  assert(req != NULL);
+  assert(handle->stream.conn.write_reqs_pending == 0);
+  SET_REQ_SUCCESS(req);
+
+  if (handle->flags & UV_HANDLE_CLOSING) {
+    uv__insert_pending_req(loop, (uv_req_t*) req);
+    return;
+  }
+
+  /* Try to avoid flushing the pipe buffer in the thread pool. */
+  nt_status = pNtQueryInformationFile(handle->handle,
+                                      &io_status,
+                                      &pipe_info,
+                                      sizeof pipe_info,
+                                      FilePipeLocalInformation);
+
+  if (nt_status != STATUS_SUCCESS) {
+    SET_REQ_ERROR(req, pRtlNtStatusToDosError(nt_status));
+    handle->flags |= UV_HANDLE_WRITABLE; /* Questionable. */
+    uv__insert_pending_req(loop, (uv_req_t*) req);
+    return;
+  }
+
+  if (pipe_info.OutboundQuota == pipe_info.WriteQuotaAvailable) {
+    /* Short-circuit, no need to call FlushFileBuffers:
+     * all writes have been read. */
+    uv__insert_pending_req(loop, (uv_req_t*) req);
+    return;
+  }
+
+  /* Run FlushFileBuffers in the thread pool. */
+  result = QueueUserWorkItem(pipe_shutdown_thread_proc,
+                             req,
+                             WT_EXECUTELONGFUNCTION);
+  if (!result) {
+    SET_REQ_ERROR(req, GetLastError());
+    handle->flags |= UV_HANDLE_WRITABLE; /* Questionable. */
+    uv__insert_pending_req(loop, (uv_req_t*) req);
+    return;
+  }
+}
+
+
+void uv__pipe_endgame(uv_loop_t* loop, uv_pipe_t* handle) {
+  uv__ipc_xfer_queue_item_t* xfer_queue_item;
+
+  assert(handle->reqs_pending == 0);
+  assert(handle->flags & UV_HANDLE_CLOSING);
+  assert(!(handle->flags & UV_HANDLE_CLOSED));
+
+  if (handle->flags & UV_HANDLE_CONNECTION) {
+    /* Free pending sockets */
+    while (!uv__queue_empty(&handle->pipe.conn.ipc_xfer_queue)) {
+      struct uv__queue* q;
+      SOCKET socket;
+
+      q = uv__queue_head(&handle->pipe.conn.ipc_xfer_queue);
+      uv__queue_remove(q);
+      xfer_queue_item = uv__queue_data(q, uv__ipc_xfer_queue_item_t, member);
+
+      /* Materialize socket and close it */
+      socket = WSASocketW(FROM_PROTOCOL_INFO,
+                          FROM_PROTOCOL_INFO,
+                          FROM_PROTOCOL_INFO,
+                          &xfer_queue_item->xfer_info.socket_info,
+                          0,
+                          WSA_FLAG_OVERLAPPED);
+      uv__free(xfer_queue_item);
+
+      if (socket != INVALID_SOCKET)
+        closesocket(socket);
+    }
+    handle->pipe.conn.ipc_xfer_queue_length = 0;
+
+    assert(handle->read_req.wait_handle == INVALID_HANDLE_VALUE);
+    if (handle->read_req.event_handle != NULL) {
+      CloseHandle(handle->read_req.event_handle);
+      handle->read_req.event_handle = NULL;
+    }
+
+    if (handle->flags & UV_HANDLE_NON_OVERLAPPED_PIPE)
+      DeleteCriticalSection(&handle->pipe.conn.readfile_thread_lock);
+  }
+
+  if (handle->flags & UV_HANDLE_PIPESERVER) {
+    assert(handle->pipe.serv.accept_reqs);
+    uv__free(handle->pipe.serv.accept_reqs);
+    handle->pipe.serv.accept_reqs = NULL;
+  }
+
+  uv__handle_close(handle);
+}
+
+
+void uv_pipe_pending_instances(uv_pipe_t* handle, int count) {
+  if (handle->flags & UV_HANDLE_BOUND)
+    return;
+  handle->pipe.serv.pending_instances = count;
+  handle->flags |= UV_HANDLE_PIPESERVER;
+}
+
+
+/* Creates a pipe server. */
+int uv_pipe_bind(uv_pipe_t* handle, const char* name) {
+  return uv_pipe_bind2(handle, name, strlen(name), 0);
+}
+
+
+int uv_pipe_bind2(uv_pipe_t* handle,
+                  const char* name,
+                  size_t namelen,
+                  unsigned int flags) {
+  uv_loop_t* loop = handle->loop;
+  int i, err;
+  uv_pipe_accept_t* req;
+  char* name_copy;
+
+  if (flags & ~UV_PIPE_NO_TRUNCATE) {
+    return UV_EINVAL;
+  }
+
+  if (name == NULL) {
+    return UV_EINVAL;
+  }
+
+  if (namelen == 0) {
+    return UV_EINVAL;
+  }
+
+  if (includes_nul(name, namelen)) {
+    return UV_EINVAL;
+  }
+
+  if (handle->flags & UV_HANDLE_BOUND) {
+    return UV_EINVAL;
+  }
+
+  if (uv__is_closing(handle)) {
+    return UV_EINVAL;
+  }
+
+  name_copy = uv__malloc(namelen + 1);
+  if (name_copy == NULL) {
+    return UV_ENOMEM;
+  }
+
+  memcpy(name_copy, name, namelen);
+  name_copy[namelen] = '\0';
+
+  if (!(handle->flags & UV_HANDLE_PIPESERVER)) {
+    handle->pipe.serv.pending_instances = default_pending_pipe_instances;
+  }
+
+  err = UV_ENOMEM;
+  handle->pipe.serv.accept_reqs = (uv_pipe_accept_t*)
+    uv__malloc(sizeof(uv_pipe_accept_t) * handle->pipe.serv.pending_instances);
+  if (handle->pipe.serv.accept_reqs == NULL) {
+    goto error;
+  }
+
+  for (i = 0; i < handle->pipe.serv.pending_instances; i++) {
+    req = &handle->pipe.serv.accept_reqs[i];
+    UV_REQ_INIT(req, UV_ACCEPT);
+    req->data = handle;
+    req->pipeHandle = INVALID_HANDLE_VALUE;
+    req->next_pending = NULL;
+  }
+
+  /* TODO(bnoordhuis) Add converters that take a |length| parameter. */
+  err = uv__convert_utf8_to_utf16(name_copy, &handle->name);
+  uv__free(name_copy);
+  name_copy = NULL;
+
+  if (err) {
+    goto error;
+  }
+
+  /*
+   * Attempt to create the first pipe with FILE_FLAG_FIRST_PIPE_INSTANCE.
+   * If this fails then there's already a pipe server for the given pipe name.
+   */
+  if (!pipe_alloc_accept(loop,
+                         handle,
+                         &handle->pipe.serv.accept_reqs[0],
+                         TRUE)) {
+    err = GetLastError();
+    if (err == ERROR_ACCESS_DENIED) {
+      err = UV_EADDRINUSE;
+    } else if (err == ERROR_PATH_NOT_FOUND || err == ERROR_INVALID_NAME) {
+      err = UV_EACCES;
+    } else {
+      err = uv_translate_sys_error(err);
+    }
+    goto error;
+  }
+
+  handle->pipe.serv.pending_accepts = NULL;
+  handle->flags |= UV_HANDLE_PIPESERVER;
+  handle->flags |= UV_HANDLE_BOUND;
+
+  return 0;
+
+error:
+  uv__free(handle->pipe.serv.accept_reqs);
+  uv__free(handle->name);
+  uv__free(name_copy);
+  handle->pipe.serv.accept_reqs = NULL;
+  handle->name = NULL;
+
+  return err;
+}
+
+
+static DWORD WINAPI pipe_connect_thread_proc(void* parameter) {
+  uv_loop_t* loop;
+  uv_pipe_t* handle;
+  uv_connect_t* req;
+  HANDLE pipeHandle = INVALID_HANDLE_VALUE;
+  DWORD duplex_flags;
+
+  req = (uv_connect_t*) parameter;
+  assert(req);
+  handle = (uv_pipe_t*) req->handle;
+  assert(handle);
+  loop = handle->loop;
+  assert(loop);
+
+  /* We're here because CreateFile on a pipe returned ERROR_PIPE_BUSY. We wait
+   * up to 30 seconds for the pipe to become available with WaitNamedPipe. */
+  while (WaitNamedPipeW(req->u.connect.name, 30000)) {
+    /* The pipe is now available, try to connect. */
+    pipeHandle = open_named_pipe(req->u.connect.name, &duplex_flags);
+    if (pipeHandle != INVALID_HANDLE_VALUE)
+      break;
+
+    SwitchToThread();
+  }
+
+  uv__free(req->u.connect.name);
+  req->u.connect.name = NULL;
+  if (pipeHandle != INVALID_HANDLE_VALUE) {
+    SET_REQ_SUCCESS(req);
+    req->u.connect.pipeHandle = pipeHandle;
+    req->u.connect.duplex_flags = duplex_flags;
+  } else {
+    SET_REQ_ERROR(req, GetLastError());
+  }
+
+  /* Post completed */
+  POST_COMPLETION_FOR_REQ(loop, req);
+
+  return 0;
+}
+
+
+void uv_pipe_connect(uv_connect_t* req,
+                    uv_pipe_t* handle,
+                    const char* name,
+                    uv_connect_cb cb) {
+  uv_loop_t* loop;
+  int err;
+
+  err = uv_pipe_connect2(req, handle, name, strlen(name), 0, cb);
+
+  if (err) {
+    loop = handle->loop;
+    /* Make this req pending reporting an error. */
+    SET_REQ_ERROR(req, err);
+    uv__insert_pending_req(loop, (uv_req_t*) req);
+    handle->reqs_pending++;
+    REGISTER_HANDLE_REQ(loop, handle);
+  }
+}
+
+
+int uv_pipe_connect2(uv_connect_t* req,
+                     uv_pipe_t* handle,
+                     const char* name,
+                     size_t namelen,
+                     unsigned int flags,
+                     uv_connect_cb cb) {
+  uv_loop_t* loop;
+  int err;
+  size_t nameSize;
+  HANDLE pipeHandle = INVALID_HANDLE_VALUE;
+  DWORD duplex_flags;
+  char* name_copy;
+
+  loop = handle->loop;
+  UV_REQ_INIT(req, UV_CONNECT);
+  req->handle = (uv_stream_t*) handle;
+  req->cb = cb;
+  req->u.connect.pipeHandle = INVALID_HANDLE_VALUE;
+  req->u.connect.duplex_flags = 0;
+  req->u.connect.name = NULL;
+
+  if (flags & ~UV_PIPE_NO_TRUNCATE) {
+    return UV_EINVAL;
+  }
+
+  if (name == NULL) {
+    return UV_EINVAL;
+  }
+
+  if (namelen == 0) {
+    return UV_EINVAL;
+  }
+
+  if (includes_nul(name, namelen)) {
+    return UV_EINVAL;
+  }
+
+  name_copy = uv__malloc(namelen + 1);
+  if (name_copy == NULL) {
+    return UV_ENOMEM;
+  }
+
+  memcpy(name_copy, name, namelen);
+  name_copy[namelen] = '\0';
+
+  if (handle->flags & UV_HANDLE_PIPESERVER) {
+    err = ERROR_INVALID_PARAMETER;
+    goto error;
+  }
+  if (handle->flags & UV_HANDLE_CONNECTION) {
+    err = ERROR_PIPE_BUSY;
+    goto error;
+  }
+  uv__pipe_connection_init(handle);
+
+  /* TODO(bnoordhuis) Add converters that take a |length| parameter. */
+  err = uv__convert_utf8_to_utf16(name_copy, &handle->name);
+  uv__free(name_copy);
+  name_copy = NULL;
+
+  if (err) {
+    err = ERROR_NO_UNICODE_TRANSLATION;
+    goto error;
+  }
+
+  pipeHandle = open_named_pipe(handle->name, &duplex_flags);
+  if (pipeHandle == INVALID_HANDLE_VALUE) {
+    if (GetLastError() == ERROR_PIPE_BUSY) {
+      nameSize = (wcslen(handle->name) + 1) * sizeof(WCHAR);
+      req->u.connect.name = uv__malloc(nameSize);
+      if (!req->u.connect.name) {
+        uv_fatal_error(ERROR_OUTOFMEMORY, "uv__malloc");
+      }
+
+      memcpy(req->u.connect.name, handle->name, nameSize);
+
+      /* Wait for the server to make a pipe instance available. */
+      if (!QueueUserWorkItem(&pipe_connect_thread_proc,
+                             req,
+                             WT_EXECUTELONGFUNCTION)) {
+        uv__free(req->u.connect.name);
+        req->u.connect.name = NULL;
+        err = GetLastError();
+        goto error;
+      }
+
+      REGISTER_HANDLE_REQ(loop, handle);
+      handle->reqs_pending++;
+
+      return 0;
+    }
+
+    err = GetLastError();
+    goto error;
+  }
+
+  req->u.connect.pipeHandle = pipeHandle;
+  req->u.connect.duplex_flags = duplex_flags;
+  SET_REQ_SUCCESS(req);
+  uv__insert_pending_req(loop, (uv_req_t*) req);
+  handle->reqs_pending++;
+  REGISTER_HANDLE_REQ(loop, handle);
+  return 0;
+
+error:
+  uv__free(name_copy);
+
+  if (handle->name) {
+    uv__free(handle->name);
+    handle->name = NULL;
+  }
+
+  if (pipeHandle != INVALID_HANDLE_VALUE)
+    CloseHandle(pipeHandle);
+
+  /* Make this req pending reporting an error. */
+  SET_REQ_ERROR(req, err);
+  uv__insert_pending_req(loop, (uv_req_t*) req);
+  handle->reqs_pending++;
+  REGISTER_HANDLE_REQ(loop, handle);
+  return 0;
+}
+
+
+void uv__pipe_interrupt_read(uv_pipe_t* handle) {
+  BOOL r;
+
+  if (!(handle->flags & UV_HANDLE_READ_PENDING))
+    return; /* No pending reads. */
+  if (handle->flags & UV_HANDLE_CANCELLATION_PENDING)
+    return; /* Already cancelled. */
+  if (handle->handle == INVALID_HANDLE_VALUE)
+    return; /* Pipe handle closed. */
+
+  if (!(handle->flags & UV_HANDLE_NON_OVERLAPPED_PIPE)) {
+    /* Cancel asynchronous read. */
+    r = CancelIoEx(handle->handle, &handle->read_req.u.io.overlapped);
+    assert(r || GetLastError() == ERROR_NOT_FOUND);
+    (void) r;
+  } else {
+    /* Cancel synchronous read (which is happening in the thread pool). */
+    HANDLE thread;
+    volatile HANDLE* thread_ptr = &handle->pipe.conn.readfile_thread_handle;
+
+    EnterCriticalSection(&handle->pipe.conn.readfile_thread_lock);
+
+    thread = *thread_ptr;
+    if (thread == NULL) {
+      /* The thread pool thread has not yet reached the point of blocking, we
+       * can pre-empt it by setting thread_handle to INVALID_HANDLE_VALUE. */
+      *thread_ptr = INVALID_HANDLE_VALUE;
+
+    } else {
+      /* Spin until the thread has acknowledged (by setting the thread to
+       * INVALID_HANDLE_VALUE) that it is past the point of blocking. */
+      while (thread != INVALID_HANDLE_VALUE) {
+        r = CancelSynchronousIo(thread);
+        assert(r || GetLastError() == ERROR_NOT_FOUND);
+        SwitchToThread(); /* Yield thread. */
+        thread = *thread_ptr;
+      }
+    }
+
+    LeaveCriticalSection(&handle->pipe.conn.readfile_thread_lock);
+  }
+
+  /* Set flag to indicate that read has been cancelled. */
+  handle->flags |= UV_HANDLE_CANCELLATION_PENDING;
+}
+
+
+void uv__pipe_read_stop(uv_pipe_t* handle) {
+  handle->flags &= ~UV_HANDLE_READING;
+  DECREASE_ACTIVE_COUNT(handle->loop, handle);
+  uv__pipe_interrupt_read(handle);
+}
+
+
+/* Cleans up uv_pipe_t (server or connection) and all resources associated with
+ * it. */
+void uv__pipe_close(uv_loop_t* loop, uv_pipe_t* handle) {
+  int i;
+  HANDLE pipeHandle;
+
+  if (handle->flags & UV_HANDLE_READING) {
+    handle->flags &= ~UV_HANDLE_READING;
+    DECREASE_ACTIVE_COUNT(loop, handle);
+  }
+
+  if (handle->flags & UV_HANDLE_LISTENING) {
+    handle->flags &= ~UV_HANDLE_LISTENING;
+    DECREASE_ACTIVE_COUNT(loop, handle);
+  }
+
+  handle->flags &= ~(UV_HANDLE_READABLE | UV_HANDLE_WRITABLE);
+
+  uv__handle_closing(handle);
+
+  uv__pipe_interrupt_read(handle);
+
+  if (handle->name) {
+    uv__free(handle->name);
+    handle->name = NULL;
+  }
+
+  if (handle->flags & UV_HANDLE_PIPESERVER) {
+    for (i = 0; i < handle->pipe.serv.pending_instances; i++) {
+      pipeHandle = handle->pipe.serv.accept_reqs[i].pipeHandle;
+      if (pipeHandle != INVALID_HANDLE_VALUE) {
+        CloseHandle(pipeHandle);
+        handle->pipe.serv.accept_reqs[i].pipeHandle = INVALID_HANDLE_VALUE;
+      }
+    }
+    handle->handle = INVALID_HANDLE_VALUE;
+  }
+
+  if (handle->flags & UV_HANDLE_CONNECTION) {
+    eof_timer_destroy(handle);
+  }
+
+  if ((handle->flags & UV_HANDLE_CONNECTION)
+      && handle->handle != INVALID_HANDLE_VALUE) {
+    /* This will eventually destroy the write queue for us too. */
+    close_pipe(handle);
+  }
+
+  if (handle->reqs_pending == 0)
+    uv__want_endgame(loop, (uv_handle_t*) handle);
+}
+
+
+static void uv__pipe_queue_accept(uv_loop_t* loop, uv_pipe_t* handle,
+    uv_pipe_accept_t* req, BOOL firstInstance) {
+  assert(handle->flags & UV_HANDLE_LISTENING);
+
+  if (!firstInstance && !pipe_alloc_accept(loop, handle, req, FALSE)) {
+    SET_REQ_ERROR(req, GetLastError());
+    uv__insert_pending_req(loop, (uv_req_t*) req);
+    handle->reqs_pending++;
+    return;
+  }
+
+  assert(req->pipeHandle != INVALID_HANDLE_VALUE);
+
+  /* Prepare the overlapped structure. */
+  memset(&(req->u.io.overlapped), 0, sizeof(req->u.io.overlapped));
+
+  if (!ConnectNamedPipe(req->pipeHandle, &req->u.io.overlapped) &&
+      GetLastError() != ERROR_IO_PENDING) {
+    if (GetLastError() == ERROR_PIPE_CONNECTED) {
+      SET_REQ_SUCCESS(req);
+    } else {
+      CloseHandle(req->pipeHandle);
+      req->pipeHandle = INVALID_HANDLE_VALUE;
+      /* Make this req pending reporting an error. */
+      SET_REQ_ERROR(req, GetLastError());
+    }
+    uv__insert_pending_req(loop, (uv_req_t*) req);
+    handle->reqs_pending++;
+    return;
+  }
+
+  /* Wait for completion via IOCP */
+  handle->reqs_pending++;
+}
+
+
+int uv__pipe_accept(uv_pipe_t* server, uv_stream_t* client) {
+  uv_loop_t* loop = server->loop;
+  uv_pipe_t* pipe_client;
+  uv_pipe_accept_t* req;
+  struct uv__queue* q;
+  uv__ipc_xfer_queue_item_t* item;
+  int err;
+
+  if (server->ipc) {
+    if (uv__queue_empty(&server->pipe.conn.ipc_xfer_queue)) {
+      /* No valid pending sockets. */
+      return WSAEWOULDBLOCK;
+    }
+
+    q = uv__queue_head(&server->pipe.conn.ipc_xfer_queue);
+    uv__queue_remove(q);
+    server->pipe.conn.ipc_xfer_queue_length--;
+    item = uv__queue_data(q, uv__ipc_xfer_queue_item_t, member);
+
+    err = uv__tcp_xfer_import(
+        (uv_tcp_t*) client, item->xfer_type, &item->xfer_info);
+
+    uv__free(item);
+
+    if (err != 0)
+      return err;
+
+  } else {
+    pipe_client = (uv_pipe_t*) client;
+    uv__pipe_connection_init(pipe_client);
+
+    /* Find a connection instance that has been connected, but not yet
+     * accepted. */
+    req = server->pipe.serv.pending_accepts;
+
+    if (!req) {
+      /* No valid connections found, so we error out. */
+      return WSAEWOULDBLOCK;
+    }
+
+    /* Initialize the client handle and copy the pipeHandle to the client */
+    pipe_client->handle = req->pipeHandle;
+    pipe_client->flags |= UV_HANDLE_READABLE | UV_HANDLE_WRITABLE;
+
+    /* Prepare the req to pick up a new connection */
+    server->pipe.serv.pending_accepts = req->next_pending;
+    req->next_pending = NULL;
+    req->pipeHandle = INVALID_HANDLE_VALUE;
+
+    server->handle = INVALID_HANDLE_VALUE;
+    if (!(server->flags & UV_HANDLE_CLOSING)) {
+      uv__pipe_queue_accept(loop, server, req, FALSE);
+    }
+  }
+
+  return 0;
+}
+
+
+/* Starts listening for connections for the given pipe. */
+int uv__pipe_listen(uv_pipe_t* handle, int backlog, uv_connection_cb cb) {
+  uv_loop_t* loop = handle->loop;
+  int i;
+
+  if (handle->flags & UV_HANDLE_LISTENING) {
+    handle->stream.serv.connection_cb = cb;
+  }
+
+  if (!(handle->flags & UV_HANDLE_BOUND)) {
+    return WSAEINVAL;
+  }
+
+  if (handle->flags & UV_HANDLE_READING) {
+    return WSAEISCONN;
+  }
+
+  if (!(handle->flags & UV_HANDLE_PIPESERVER)) {
+    return ERROR_NOT_SUPPORTED;
+  }
+
+  if (handle->ipc) {
+    return WSAEINVAL;
+  }
+
+  handle->flags |= UV_HANDLE_LISTENING;
+  INCREASE_ACTIVE_COUNT(loop, handle);
+  handle->stream.serv.connection_cb = cb;
+
+  /* First pipe handle should have already been created in uv_pipe_bind */
+  assert(handle->pipe.serv.accept_reqs[0].pipeHandle != INVALID_HANDLE_VALUE);
+
+  for (i = 0; i < handle->pipe.serv.pending_instances; i++) {
+    uv__pipe_queue_accept(loop, handle, &handle->pipe.serv.accept_reqs[i], i == 0);
+  }
+
+  return 0;
+}
+
+
+static DWORD WINAPI uv_pipe_zero_readfile_thread_proc(void* arg) {
+  uv_read_t* req = (uv_read_t*) arg;
+  uv_pipe_t* handle = (uv_pipe_t*) req->data;
+  uv_loop_t* loop = handle->loop;
+  volatile HANDLE* thread_ptr = &handle->pipe.conn.readfile_thread_handle;
+  CRITICAL_SECTION* lock = &handle->pipe.conn.readfile_thread_lock;
+  HANDLE thread;
+  DWORD bytes;
+  DWORD err;
+
+  assert(req->type == UV_READ);
+  assert(handle->type == UV_NAMED_PIPE);
+
+  err = 0;
+
+  /* Create a handle to the current thread. */
+  if (!DuplicateHandle(GetCurrentProcess(),
+                       GetCurrentThread(),
+                       GetCurrentProcess(),
+                       &thread,
+                       0,
+                       FALSE,
+                       DUPLICATE_SAME_ACCESS)) {
+    err = GetLastError();
+    goto out1;
+  }
+
+  /* The lock needs to be held when thread handle is modified. */
+  EnterCriticalSection(lock);
+  if (*thread_ptr == INVALID_HANDLE_VALUE) {
+    /* uv__pipe_interrupt_read() cancelled reading before we got here. */
+    err = ERROR_OPERATION_ABORTED;
+  } else {
+    /* Let main thread know which worker thread is doing the blocking read. */
+    assert(*thread_ptr == NULL);
+    *thread_ptr = thread;
+  }
+  LeaveCriticalSection(lock);
+
+  if (err)
+    goto out2;
+
+  /* Block the thread until data is available on the pipe, or the read is
+   * cancelled. */
+  if (!ReadFile(handle->handle, &uv_zero_, 0, &bytes, NULL))
+    err = GetLastError();
+
+  /* Let the main thread know the worker is past the point of blocking. */
+  assert(thread == *thread_ptr);
+  *thread_ptr = INVALID_HANDLE_VALUE;
+
+  /* Briefly acquire the mutex. Since the main thread holds the lock while it
+   * is spinning trying to cancel this thread's I/O, we will block here until
+   * it stops doing that. */
+  EnterCriticalSection(lock);
+  LeaveCriticalSection(lock);
+
+out2:
+  /* Close the handle to the current thread. */
+  CloseHandle(thread);
+
+out1:
+  /* Set request status and post a completion record to the IOCP. */
+  if (err)
+    SET_REQ_ERROR(req, err);
+  else
+    SET_REQ_SUCCESS(req);
+  POST_COMPLETION_FOR_REQ(loop, req);
+
+  return 0;
+}
+
+
+static DWORD WINAPI uv_pipe_writefile_thread_proc(void* parameter) {
+  int result;
+  DWORD bytes;
+  uv_write_t* req = (uv_write_t*) parameter;
+  uv_pipe_t* handle = (uv_pipe_t*) req->handle;
+  uv_loop_t* loop = handle->loop;
+
+  assert(req != NULL);
+  assert(req->type == UV_WRITE);
+  assert(handle->type == UV_NAMED_PIPE);
+
+  result = WriteFile(handle->handle,
+                     req->write_buffer.base,
+                     req->write_buffer.len,
+                     &bytes,
+                     NULL);
+
+  if (!result) {
+    SET_REQ_ERROR(req, GetLastError());
+  }
+
+  POST_COMPLETION_FOR_REQ(loop, req);
+  return 0;
+}
+
+
+static void CALLBACK post_completion_read_wait(void* context, BOOLEAN timed_out) {
+  uv_read_t* req;
+  uv_tcp_t* handle;
+
+  req = (uv_read_t*) context;
+  assert(req != NULL);
+  handle = (uv_tcp_t*)req->data;
+  assert(handle != NULL);
+  assert(!timed_out);
+
+  if (!PostQueuedCompletionStatus(handle->loop->iocp,
+                                  req->u.io.overlapped.InternalHigh,
+                                  0,
+                                  &req->u.io.overlapped)) {
+    uv_fatal_error(GetLastError(), "PostQueuedCompletionStatus");
+  }
+}
+
+
+static void CALLBACK post_completion_write_wait(void* context, BOOLEAN timed_out) {
+  uv_write_t* req;
+  uv_tcp_t* handle;
+
+  req = (uv_write_t*) context;
+  assert(req != NULL);
+  handle = (uv_tcp_t*)req->handle;
+  assert(handle != NULL);
+  assert(!timed_out);
+
+  if (!PostQueuedCompletionStatus(handle->loop->iocp,
+                                  req->u.io.overlapped.InternalHigh,
+                                  0,
+                                  &req->u.io.overlapped)) {
+    uv_fatal_error(GetLastError(), "PostQueuedCompletionStatus");
+  }
+}
+
+
+static void uv__pipe_queue_read(uv_loop_t* loop, uv_pipe_t* handle) {
+  uv_read_t* req;
+  int result;
+
+  assert(handle->flags & UV_HANDLE_READING);
+  assert(!(handle->flags & UV_HANDLE_READ_PENDING));
+
+  assert(handle->handle != INVALID_HANDLE_VALUE);
+
+  req = &handle->read_req;
+
+  if (handle->flags & UV_HANDLE_NON_OVERLAPPED_PIPE) {
+    handle->pipe.conn.readfile_thread_handle = NULL; /* Reset cancellation. */
+    if (!QueueUserWorkItem(&uv_pipe_zero_readfile_thread_proc,
+                           req,
+                           WT_EXECUTELONGFUNCTION)) {
+      /* Make this req pending reporting an error. */
+      SET_REQ_ERROR(req, GetLastError());
+      goto error;
+    }
+  } else {
+    memset(&req->u.io.overlapped, 0, sizeof(req->u.io.overlapped));
+    if (handle->flags & UV_HANDLE_EMULATE_IOCP) {
+      assert(req->event_handle != NULL);
+      req->u.io.overlapped.hEvent = (HANDLE) ((uintptr_t) req->event_handle | 1);
+    }
+
+    /* Do 0-read */
+    result = ReadFile(handle->handle,
+                      &uv_zero_,
+                      0,
+                      NULL,
+                      &req->u.io.overlapped);
+
+    if (!result && GetLastError() != ERROR_IO_PENDING) {
+      /* Make this req pending reporting an error. */
+      SET_REQ_ERROR(req, GetLastError());
+      goto error;
+    }
+
+    if (handle->flags & UV_HANDLE_EMULATE_IOCP) {
+      assert(req->wait_handle == INVALID_HANDLE_VALUE);
+      if (!RegisterWaitForSingleObject(&req->wait_handle,
+          req->event_handle, post_completion_read_wait, (void*) req,
+          INFINITE, WT_EXECUTEINWAITTHREAD | WT_EXECUTEONLYONCE)) {
+        SET_REQ_ERROR(req, GetLastError());
+        goto error;
+      }
+    }
+  }
+
+  /* Start the eof timer if there is one */
+  eof_timer_start(handle);
+  handle->flags |= UV_HANDLE_READ_PENDING;
+  handle->reqs_pending++;
+  return;
+
+error:
+  uv__insert_pending_req(loop, (uv_req_t*)req);
+  handle->flags |= UV_HANDLE_READ_PENDING;
+  handle->reqs_pending++;
+}
+
+
+int uv__pipe_read_start(uv_pipe_t* handle,
+                        uv_alloc_cb alloc_cb,
+                        uv_read_cb read_cb) {
+  uv_loop_t* loop = handle->loop;
+
+  handle->flags |= UV_HANDLE_READING;
+  INCREASE_ACTIVE_COUNT(loop, handle);
+  handle->read_cb = read_cb;
+  handle->alloc_cb = alloc_cb;
+
+  if (handle->read_req.event_handle == NULL) {
+    handle->read_req.event_handle = CreateEvent(NULL, 0, 0, NULL);
+    if (handle->read_req.event_handle == NULL) {
+      uv_fatal_error(GetLastError(), "CreateEvent");
+    }
+  }
+
+  /* If reading was stopped and then started again, there could still be a read
+   * request pending. */
+  if (!(handle->flags & UV_HANDLE_READ_PENDING)) {
+    uv__pipe_queue_read(loop, handle);
+  }
+
+  return 0;
+}
+
+
+static void uv__insert_non_overlapped_write_req(uv_pipe_t* handle,
+    uv_write_t* req) {
+  req->next_req = NULL;
+  if (handle->pipe.conn.non_overlapped_writes_tail) {
+    req->next_req =
+      handle->pipe.conn.non_overlapped_writes_tail->next_req;
+    handle->pipe.conn.non_overlapped_writes_tail->next_req = (uv_req_t*)req;
+    handle->pipe.conn.non_overlapped_writes_tail = req;
+  } else {
+    req->next_req = (uv_req_t*)req;
+    handle->pipe.conn.non_overlapped_writes_tail = req;
+  }
+}
+
+
+static uv_write_t* uv_remove_non_overlapped_write_req(uv_pipe_t* handle) {
+  uv_write_t* req;
+
+  if (handle->pipe.conn.non_overlapped_writes_tail) {
+    req = (uv_write_t*)handle->pipe.conn.non_overlapped_writes_tail->next_req;
+
+    if (req == handle->pipe.conn.non_overlapped_writes_tail) {
+      handle->pipe.conn.non_overlapped_writes_tail = NULL;
+    } else {
+      handle->pipe.conn.non_overlapped_writes_tail->next_req =
+        req->next_req;
+    }
+
+    return req;
+  } else {
+    /* queue empty */
+    return NULL;
+  }
+}
+
+
+static void uv__queue_non_overlapped_write(uv_pipe_t* handle) {
+  uv_write_t* req = uv_remove_non_overlapped_write_req(handle);
+  if (req) {
+    if (!QueueUserWorkItem(&uv_pipe_writefile_thread_proc,
+                           req,
+                           WT_EXECUTELONGFUNCTION)) {
+      uv_fatal_error(GetLastError(), "QueueUserWorkItem");
+    }
+  }
+}
+
+
+static int uv__build_coalesced_write_req(uv_write_t* user_req,
+                                         const uv_buf_t bufs[],
+                                         size_t nbufs,
+                                         uv_write_t** req_out,
+                                         uv_buf_t* write_buf_out) {
+  /* Pack into a single heap-allocated buffer:
+   *   (a) a uv_write_t structure where libuv stores the actual state.
+   *   (b) a pointer to the original uv_write_t.
+   *   (c) data from all `bufs` entries.
+   */
+  char* heap_buffer;
+  size_t heap_buffer_length, heap_buffer_offset;
+  uv__coalesced_write_t* coalesced_write_req; /* (a) + (b) */
+  char* data_start;                           /* (c) */
+  size_t data_length;
+  unsigned int i;
+
+  /* Compute combined size of all combined buffers from `bufs`. */
+  data_length = 0;
+  for (i = 0; i < nbufs; i++)
+    data_length += bufs[i].len;
+
+  /* The total combined size of data buffers should not exceed UINT32_MAX,
+   * because WriteFile() won't accept buffers larger than that. */
+  if (data_length > UINT32_MAX)
+    return WSAENOBUFS; /* Maps to UV_ENOBUFS. */
+
+  /* Compute heap buffer size. */
+  heap_buffer_length = sizeof *coalesced_write_req + /* (a) + (b) */
+                       data_length;                  /* (c) */
+
+  /* Allocate buffer. */
+  heap_buffer = uv__malloc(heap_buffer_length);
+  if (heap_buffer == NULL)
+    return ERROR_NOT_ENOUGH_MEMORY; /* Maps to UV_ENOMEM. */
+
+  /* Copy uv_write_t information to the buffer. */
+  coalesced_write_req = (uv__coalesced_write_t*) heap_buffer;
+  coalesced_write_req->req = *user_req; /* copy (a) */
+  coalesced_write_req->req.coalesced = 1;
+  coalesced_write_req->user_req = user_req;         /* copy (b) */
+  heap_buffer_offset = sizeof *coalesced_write_req; /* offset (a) + (b) */
+
+  /* Copy data buffers to the heap buffer. */
+  data_start = &heap_buffer[heap_buffer_offset];
+  for (i = 0; i < nbufs; i++) {
+    memcpy(&heap_buffer[heap_buffer_offset],
+           bufs[i].base,
+           bufs[i].len);               /* copy (c) */
+    heap_buffer_offset += bufs[i].len; /* offset (c) */
+  }
+  assert(heap_buffer_offset == heap_buffer_length);
+
+  /* Set out arguments and return. */
+  *req_out = &coalesced_write_req->req;
+  *write_buf_out = uv_buf_init(data_start, (unsigned int) data_length);
+  return 0;
+}
+
+
+static int uv__pipe_write_data(uv_loop_t* loop,
+                               uv_write_t* req,
+                               uv_pipe_t* handle,
+                               const uv_buf_t bufs[],
+                               size_t nbufs,
+                               uv_write_cb cb,
+                               int copy_always) {
+  int err;
+  int result;
+  uv_buf_t write_buf;
+
+  assert(handle->handle != INVALID_HANDLE_VALUE);
+
+  UV_REQ_INIT(req, UV_WRITE);
+  req->handle = (uv_stream_t*) handle;
+  req->send_handle = NULL;
+  req->cb = cb;
+  /* Private fields. */
+  req->coalesced = 0;
+  req->event_handle = NULL;
+  req->wait_handle = INVALID_HANDLE_VALUE;
+
+  /* Prepare the overlapped structure. */
+  memset(&req->u.io.overlapped, 0, sizeof(req->u.io.overlapped));
+  if (handle->flags & (UV_HANDLE_EMULATE_IOCP | UV_HANDLE_BLOCKING_WRITES)) {
+    req->event_handle = CreateEvent(NULL, 0, 0, NULL);
+    if (req->event_handle == NULL) {
+      uv_fatal_error(GetLastError(), "CreateEvent");
+    }
+    req->u.io.overlapped.hEvent = (HANDLE) ((uintptr_t) req->event_handle | 1);
+  }
+  req->write_buffer = uv_null_buf_;
+
+  if (nbufs == 0) {
+    /* Write empty buffer. */
+    write_buf = uv_null_buf_;
+  } else if (nbufs == 1 && !copy_always) {
+    /* Write directly from bufs[0]. */
+    write_buf = bufs[0];
+  } else {
+    /* Coalesce all `bufs` into one big buffer. This also creates a new
+     * write-request structure that replaces the old one. */
+    err = uv__build_coalesced_write_req(req, bufs, nbufs, &req, &write_buf);
+    if (err != 0)
+      return err;
+  }
+
+  if ((handle->flags &
+      (UV_HANDLE_BLOCKING_WRITES | UV_HANDLE_NON_OVERLAPPED_PIPE)) ==
+      (UV_HANDLE_BLOCKING_WRITES | UV_HANDLE_NON_OVERLAPPED_PIPE)) {
+    DWORD bytes;
+    result =
+        WriteFile(handle->handle, write_buf.base, write_buf.len, &bytes, NULL);
+
+    if (!result) {
+      err = GetLastError();
+      return err;
+    } else {
+      /* Request completed immediately. */
+      req->u.io.queued_bytes = 0;
+    }
+
+    REGISTER_HANDLE_REQ(loop, handle);
+    handle->reqs_pending++;
+    handle->stream.conn.write_reqs_pending++;
+    POST_COMPLETION_FOR_REQ(loop, req);
+    return 0;
+  } else if (handle->flags & UV_HANDLE_NON_OVERLAPPED_PIPE) {
+    req->write_buffer = write_buf;
+    uv__insert_non_overlapped_write_req(handle, req);
+    if (handle->stream.conn.write_reqs_pending == 0) {
+      uv__queue_non_overlapped_write(handle);
+    }
+
+    /* Request queued by the kernel. */
+    req->u.io.queued_bytes = write_buf.len;
+    handle->write_queue_size += req->u.io.queued_bytes;
+  } else if (handle->flags & UV_HANDLE_BLOCKING_WRITES) {
+    /* Using overlapped IO, but wait for completion before returning */
+    result = WriteFile(handle->handle,
+                       write_buf.base,
+                       write_buf.len,
+                       NULL,
+                       &req->u.io.overlapped);
+
+    if (!result && GetLastError() != ERROR_IO_PENDING) {
+      err = GetLastError();
+      CloseHandle(req->event_handle);
+      req->event_handle = NULL;
+      return err;
+    }
+
+    if (result) {
+      /* Request completed immediately. */
+      req->u.io.queued_bytes = 0;
+    } else {
+      /* Request queued by the kernel. */
+      req->u.io.queued_bytes = write_buf.len;
+      handle->write_queue_size += req->u.io.queued_bytes;
+      if (WaitForSingleObject(req->event_handle, INFINITE) !=
+          WAIT_OBJECT_0) {
+        err = GetLastError();
+        CloseHandle(req->event_handle);
+        req->event_handle = NULL;
+        return err;
+      }
+    }
+    CloseHandle(req->event_handle);
+    req->event_handle = NULL;
+
+    REGISTER_HANDLE_REQ(loop, handle);
+    handle->reqs_pending++;
+    handle->stream.conn.write_reqs_pending++;
+    return 0;
+  } else {
+    result = WriteFile(handle->handle,
+                       write_buf.base,
+                       write_buf.len,
+                       NULL,
+                       &req->u.io.overlapped);
+
+    if (!result && GetLastError() != ERROR_IO_PENDING) {
+      return GetLastError();
+    }
+
+    if (result) {
+      /* Request completed immediately. */
+      req->u.io.queued_bytes = 0;
+    } else {
+      /* Request queued by the kernel. */
+      req->u.io.queued_bytes = write_buf.len;
+      handle->write_queue_size += req->u.io.queued_bytes;
+    }
+
+    if (handle->flags & UV_HANDLE_EMULATE_IOCP) {
+      if (!RegisterWaitForSingleObject(&req->wait_handle,
+          req->event_handle, post_completion_write_wait, (void*) req,
+          INFINITE, WT_EXECUTEINWAITTHREAD | WT_EXECUTEONLYONCE)) {
+        return GetLastError();
+      }
+    }
+  }
+
+  REGISTER_HANDLE_REQ(loop, handle);
+  handle->reqs_pending++;
+  handle->stream.conn.write_reqs_pending++;
+
+  return 0;
+}
+
+
+static DWORD uv__pipe_get_ipc_remote_pid(uv_pipe_t* handle) {
+  DWORD* pid = &handle->pipe.conn.ipc_remote_pid;
+
+  /* If the both ends of the IPC pipe are owned by the same process,
+   * the remote end pid may not yet be set. If so, do it here.
+   * TODO: this is weird; it'd probably better to use a handshake. */
+  if (*pid == 0) {
+    GetNamedPipeClientProcessId(handle->handle, pid);
+    if (*pid == GetCurrentProcessId()) {
+      GetNamedPipeServerProcessId(handle->handle, pid);
+    }
+  }
+
+  return *pid;
+}
+
+
+int uv__pipe_write_ipc(uv_loop_t* loop,
+                       uv_write_t* req,
+                       uv_pipe_t* handle,
+                       const uv_buf_t data_bufs[],
+                       size_t data_buf_count,
+                       uv_stream_t* send_handle,
+                       uv_write_cb cb) {
+  uv_buf_t stack_bufs[6];
+  uv_buf_t* bufs;
+  size_t buf_count, buf_index;
+  uv__ipc_frame_header_t frame_header;
+  uv__ipc_socket_xfer_type_t xfer_type = UV__IPC_SOCKET_XFER_NONE;
+  uv__ipc_socket_xfer_info_t xfer_info;
+  uint64_t data_length;
+  size_t i;
+  int err;
+
+  /* Compute the combined size of data buffers. */
+  data_length = 0;
+  for (i = 0; i < data_buf_count; i++)
+    data_length += data_bufs[i].len;
+  if (data_length > UINT32_MAX)
+    return WSAENOBUFS; /* Maps to UV_ENOBUFS. */
+
+  /* Prepare the frame's socket xfer payload. */
+  if (send_handle != NULL) {
+    uv_tcp_t* send_tcp_handle = (uv_tcp_t*) send_handle;
+
+    /* Verify that `send_handle` it is indeed a tcp handle. */
+    if (send_tcp_handle->type != UV_TCP)
+      return ERROR_NOT_SUPPORTED;
+
+    /* Export the tcp handle. */
+    err = uv__tcp_xfer_export(send_tcp_handle,
+                              uv__pipe_get_ipc_remote_pid(handle),
+                              &xfer_type,
+                              &xfer_info);
+    if (err != 0)
+      return err;
+  }
+
+  /* Compute the number of uv_buf_t's required. */
+  buf_count = 1 + data_buf_count; /* Frame header and data buffers. */
+  if (send_handle != NULL)
+    buf_count += 1; /* One extra for the socket xfer information. */
+
+  /* Use the on-stack buffer array if it is big enough; otherwise allocate
+   * space for it on the heap. */
+  if (buf_count < ARRAY_SIZE(stack_bufs)) {
+    /* Use on-stack buffer array. */
+    bufs = stack_bufs;
+  } else {
+    /* Use heap-allocated buffer array. */
+    bufs = uv__calloc(buf_count, sizeof(uv_buf_t));
+    if (bufs == NULL)
+      return ERROR_NOT_ENOUGH_MEMORY; /* Maps to UV_ENOMEM. */
+  }
+  buf_index = 0;
+
+  /* Initialize frame header and add it to the buffers list. */
+  memset(&frame_header, 0, sizeof frame_header);
+  bufs[buf_index++] = uv_buf_init((char*) &frame_header, sizeof frame_header);
+
+  if (send_handle != NULL) {
+    /* Add frame header flags. */
+    switch (xfer_type) {
+      case UV__IPC_SOCKET_XFER_TCP_CONNECTION:
+        frame_header.flags |= UV__IPC_FRAME_HAS_SOCKET_XFER |
+                              UV__IPC_FRAME_XFER_IS_TCP_CONNECTION;
+        break;
+      case UV__IPC_SOCKET_XFER_TCP_SERVER:
+        frame_header.flags |= UV__IPC_FRAME_HAS_SOCKET_XFER;
+        break;
+      default:
+        assert(0);  /* Unreachable. */
+    }
+    /* Add xfer info buffer. */
+    bufs[buf_index++] = uv_buf_init((char*) &xfer_info, sizeof xfer_info);
+  }
+
+  if (data_length > 0) {
+    /* Update frame header. */
+    frame_header.flags |= UV__IPC_FRAME_HAS_DATA;
+    frame_header.data_length = (uint32_t) data_length;
+    /* Add data buffers to buffers list. */
+    for (i = 0; i < data_buf_count; i++)
+      bufs[buf_index++] = data_bufs[i];
+  }
+
+  /* Write buffers. We set the `always_copy` flag, so it is not a problem that
+   * some of the written data lives on the stack. */
+  err = uv__pipe_write_data(loop, req, handle, bufs, buf_count, cb, 1);
+
+  /* If we had to heap-allocate the bufs array, free it now. */
+  if (bufs != stack_bufs) {
+    uv__free(bufs);
+  }
+
+  return err;
+}
+
+
+int uv__pipe_write(uv_loop_t* loop,
+                   uv_write_t* req,
+                   uv_pipe_t* handle,
+                   const uv_buf_t bufs[],
+                   size_t nbufs,
+                   uv_stream_t* send_handle,
+                   uv_write_cb cb) {
+  if (handle->ipc) {
+    /* IPC pipe write: use framing protocol. */
+    return uv__pipe_write_ipc(loop, req, handle, bufs, nbufs, send_handle, cb);
+  } else {
+    /* Non-IPC pipe write: put data on the wire directly. */
+    assert(send_handle == NULL);
+    return uv__pipe_write_data(loop, req, handle, bufs, nbufs, cb, 0);
+  }
+}
+
+
+static void uv__pipe_read_eof(uv_loop_t* loop, uv_pipe_t* handle,
+    uv_buf_t buf) {
+  /* If there is an eof timer running, we don't need it any more, so discard
+   * it. */
+  eof_timer_destroy(handle);
+
+  uv_read_stop((uv_stream_t*) handle);
+
+  handle->read_cb((uv_stream_t*) handle, UV_EOF, &buf);
+}
+
+
+static void uv__pipe_read_error(uv_loop_t* loop, uv_pipe_t* handle, int error,
+    uv_buf_t buf) {
+  /* If there is an eof timer running, we don't need it any more, so discard
+   * it. */
+  eof_timer_destroy(handle);
+
+  uv_read_stop((uv_stream_t*) handle);
+
+  handle->read_cb((uv_stream_t*)handle, uv_translate_sys_error(error), &buf);
+}
+
+
+static void uv__pipe_read_error_or_eof(uv_loop_t* loop, uv_pipe_t* handle,
+    DWORD error, uv_buf_t buf) {
+  if (error == ERROR_BROKEN_PIPE) {
+    uv__pipe_read_eof(loop, handle, buf);
+  } else {
+    uv__pipe_read_error(loop, handle, error, buf);
+  }
+}
+
+
+static void uv__pipe_queue_ipc_xfer_info(
+    uv_pipe_t* handle,
+    uv__ipc_socket_xfer_type_t xfer_type,
+    uv__ipc_socket_xfer_info_t* xfer_info) {
+  uv__ipc_xfer_queue_item_t* item;
+
+  item = (uv__ipc_xfer_queue_item_t*) uv__malloc(sizeof(*item));
+  if (item == NULL)
+    uv_fatal_error(ERROR_OUTOFMEMORY, "uv__malloc");
+
+  item->xfer_type = xfer_type;
+  item->xfer_info = *xfer_info;
+
+  uv__queue_insert_tail(&handle->pipe.conn.ipc_xfer_queue, &item->member);
+  handle->pipe.conn.ipc_xfer_queue_length++;
+}
+
+
+/* Read an exact number of bytes from a pipe. If an error or end-of-file is
+ * encountered before the requested number of bytes are read, an error is
+ * returned. */
+static DWORD uv__pipe_read_exactly(uv_pipe_t* handle, void* buffer, DWORD count) {
+  uv_read_t* req;
+  DWORD bytes_read;
+  DWORD bytes_read_now;
+
+  bytes_read = 0;
+  while (bytes_read < count) {
+    req = &handle->read_req;
+    memset(&req->u.io.overlapped, 0, sizeof(req->u.io.overlapped));
+    req->u.io.overlapped.hEvent = (HANDLE) ((uintptr_t) req->event_handle | 1);
+    if (!ReadFile(handle->handle,
+                  (char*) buffer + bytes_read,
+                  count - bytes_read,
+                  &bytes_read_now,
+                  &req->u.io.overlapped)) {
+      if (GetLastError() != ERROR_IO_PENDING)
+        return GetLastError();
+      if (!GetOverlappedResult(handle->handle, &req->u.io.overlapped, &bytes_read_now, TRUE))
+        return GetLastError();
+    }
+
+    bytes_read += bytes_read_now;
+  }
+
+  assert(bytes_read == count);
+  return 0;
+}
+
+
+static int uv__pipe_read_data(uv_loop_t* loop,
+                              uv_pipe_t* handle,
+                              DWORD* bytes_read, /* inout argument */
+                              DWORD max_bytes) {
+  uv_buf_t buf;
+  uv_read_t* req;
+  DWORD r;
+  DWORD bytes_available;
+  int more;
+
+  /* Ask the user for a buffer to read data into. */
+  buf = uv_buf_init(NULL, 0);
+  handle->alloc_cb((uv_handle_t*) handle, *bytes_read, &buf);
+  if (buf.base == NULL || buf.len == 0) {
+    handle->read_cb((uv_stream_t*) handle, UV_ENOBUFS, &buf);
+    return 0; /* Break out of read loop. */
+  }
+
+  /* Ensure we read at most the smaller of:
+   *   (a) the length of the user-allocated buffer.
+   *   (b) the maximum data length as specified by the `max_bytes` argument.
+   *   (c) the amount of data that can be read non-blocking
+   */
+  if (max_bytes > buf.len)
+    max_bytes = buf.len;
+
+  if (handle->flags & UV_HANDLE_NON_OVERLAPPED_PIPE) {
+    /* The user failed to supply a pipe that can be used non-blocking or with
+     * threads. Try to estimate the amount of data that is safe to read without
+     * blocking, in a race-y way however. */
+    bytes_available = 0;
+    if (!PeekNamedPipe(handle->handle, NULL, 0, NULL, &bytes_available, NULL)) {
+      r = GetLastError();
+    } else {
+      if (max_bytes > bytes_available)
+        max_bytes = bytes_available;
+      *bytes_read = 0;
+      if (max_bytes == 0 || ReadFile(handle->handle, buf.base, max_bytes, bytes_read, NULL))
+        r = ERROR_SUCCESS;
+      else
+        r = GetLastError();
+    }
+    more = max_bytes < bytes_available;
+  } else {
+    /* Read into the user buffer.
+     * Prepare an Event so that we can cancel if it doesn't complete immediately.
+     */
+    req = &handle->read_req;
+    memset(&req->u.io.overlapped, 0, sizeof(req->u.io.overlapped));
+    req->u.io.overlapped.hEvent = (HANDLE) ((uintptr_t) req->event_handle | 1);
+    if (ReadFile(handle->handle, buf.base, max_bytes, bytes_read, &req->u.io.overlapped)) {
+      r = ERROR_SUCCESS;
+    } else {
+      r = GetLastError();
+      *bytes_read = 0;
+      if (r == ERROR_IO_PENDING) {
+        r = CancelIoEx(handle->handle, &req->u.io.overlapped);
+        assert(r || GetLastError() == ERROR_NOT_FOUND);
+        if (GetOverlappedResult(handle->handle, &req->u.io.overlapped, bytes_read, TRUE)) {
+          r = ERROR_SUCCESS;
+        } else {
+          r = GetLastError();
+          *bytes_read = 0;
+        }
+      }
+    }
+    more = *bytes_read == max_bytes;
+  }
+
+  /* Call the read callback. */
+  if (r == ERROR_SUCCESS || r == ERROR_OPERATION_ABORTED)
+    handle->read_cb((uv_stream_t*) handle, *bytes_read, &buf);
+  else
+    uv__pipe_read_error_or_eof(loop, handle, r, buf);
+
+  return more;
+}
+
+
+static int uv__pipe_read_ipc(uv_loop_t* loop, uv_pipe_t* handle) {
+  uint32_t* data_remaining;
+  DWORD err;
+  DWORD more;
+  DWORD bytes_read;
+
+  data_remaining = &handle->pipe.conn.ipc_data_frame.payload_remaining;
+
+  if (*data_remaining > 0) {
+    /* Read frame data payload. */
+    bytes_read = *data_remaining;
+    more = uv__pipe_read_data(loop, handle, &bytes_read, bytes_read);
+    *data_remaining -= bytes_read;
+
+  } else {
+    /* Start of a new IPC frame. */
+    uv__ipc_frame_header_t frame_header;
+    uint32_t xfer_flags;
+    uv__ipc_socket_xfer_type_t xfer_type;
+    uv__ipc_socket_xfer_info_t xfer_info;
+
+    /* Read the IPC frame header. */
+    err = uv__pipe_read_exactly(
+        handle, &frame_header, sizeof frame_header);
+    if (err)
+      goto error;
+
+    /* Validate that flags are valid. */
+    if ((frame_header.flags & ~UV__IPC_FRAME_VALID_FLAGS) != 0)
+      goto invalid;
+    /* Validate that reserved2 is zero. */
+    if (frame_header.reserved2 != 0)
+      goto invalid;
+
+    /* Parse xfer flags. */
+    xfer_flags = frame_header.flags & UV__IPC_FRAME_XFER_FLAGS;
+    if (xfer_flags & UV__IPC_FRAME_HAS_SOCKET_XFER) {
+      /* Socket coming -- determine the type. */
+      xfer_type = xfer_flags & UV__IPC_FRAME_XFER_IS_TCP_CONNECTION
+                      ? UV__IPC_SOCKET_XFER_TCP_CONNECTION
+                      : UV__IPC_SOCKET_XFER_TCP_SERVER;
+    } else if (xfer_flags == 0) {
+      /* No socket. */
+      xfer_type = UV__IPC_SOCKET_XFER_NONE;
+    } else {
+      /* Invalid flags. */
+      goto invalid;
+    }
+
+    /* Parse data frame information. */
+    if (frame_header.flags & UV__IPC_FRAME_HAS_DATA) {
+      *data_remaining = frame_header.data_length;
+    } else if (frame_header.data_length != 0) {
+      /* Data length greater than zero but data flag not set -- invalid. */
+      goto invalid;
+    }
+
+    /* If no socket xfer info follows, return here. Data will be read in a
+     * subsequent invocation of uv__pipe_read_ipc(). */
+    if (xfer_type != UV__IPC_SOCKET_XFER_NONE) {
+      /* Read transferred socket information. */
+      err = uv__pipe_read_exactly(handle, &xfer_info, sizeof xfer_info);
+      if (err)
+        goto error;
+
+      /* Store the pending socket info. */
+      uv__pipe_queue_ipc_xfer_info(handle, xfer_type, &xfer_info);
+    }
+  }
+
+  /* Return whether the caller should immediately try another read call to get
+   * more data. Calling uv__pipe_read_exactly will hang if there isn't data
+   * available, so we cannot do this unless we are guaranteed not to reach that.
+   */
+  more = *data_remaining > 0;
+  return more;
+
+invalid:
+  /* Invalid frame. */
+  err = WSAECONNABORTED; /* Maps to UV_ECONNABORTED. */
+
+error:
+  uv__pipe_read_error_or_eof(loop, handle, err, uv_null_buf_);
+  return 0; /* Break out of read loop. */
+}
+
+
+void uv__process_pipe_read_req(uv_loop_t* loop,
+                               uv_pipe_t* handle,
+                               uv_req_t* req) {
+  DWORD err;
+  DWORD more;
+  DWORD bytes_requested;
+  assert(handle->type == UV_NAMED_PIPE);
+
+  handle->flags &= ~(UV_HANDLE_READ_PENDING | UV_HANDLE_CANCELLATION_PENDING);
+  DECREASE_PENDING_REQ_COUNT(handle);
+  eof_timer_stop(handle);
+
+  if (handle->read_req.wait_handle != INVALID_HANDLE_VALUE) {
+    UnregisterWait(handle->read_req.wait_handle);
+    handle->read_req.wait_handle = INVALID_HANDLE_VALUE;
+  }
+
+  /* At this point, we're done with bookkeeping. If the user has stopped
+   * reading the pipe in the meantime, there is nothing left to do, since there
+   * is no callback that we can call. */
+  if (!(handle->flags & UV_HANDLE_READING))
+    return;
+
+  if (!REQ_SUCCESS(req)) {
+    /* An error occurred doing the zero-read. */
+    err = GET_REQ_ERROR(req);
+
+    /* If the read was cancelled by uv__pipe_interrupt_read(), the request may
+     * indicate an ERROR_OPERATION_ABORTED error. This error isn't relevant to
+     * the user; we'll start a new zero-read at the end of this function. */
+    if (err != ERROR_OPERATION_ABORTED)
+      uv__pipe_read_error_or_eof(loop, handle, err, uv_null_buf_);
+
+  } else {
+    /* The zero-read completed without error, indicating there is data
+     * available in the kernel buffer. */
+    while (handle->flags & UV_HANDLE_READING) {
+      bytes_requested = 65536;
+      /* Depending on the type of pipe, read either IPC frames or raw data. */
+      if (handle->ipc)
+          more = uv__pipe_read_ipc(loop, handle);
+      else
+          more = uv__pipe_read_data(loop, handle, &bytes_requested, INT32_MAX);
+
+      /* If no bytes were read, treat this as an indication that an error
+       * occurred, and break out of the read loop. */
+      if (more == 0)
+        break;
+    }
+  }
+
+  /* Start another zero-read request if necessary. */
+  if ((handle->flags & UV_HANDLE_READING) &&
+      !(handle->flags & UV_HANDLE_READ_PENDING)) {
+    uv__pipe_queue_read(loop, handle);
+  }
+}
+
+
+void uv__process_pipe_write_req(uv_loop_t* loop, uv_pipe_t* handle,
+    uv_write_t* req) {
+  int err;
+
+  assert(handle->type == UV_NAMED_PIPE);
+
+  assert(handle->write_queue_size >= req->u.io.queued_bytes);
+  handle->write_queue_size -= req->u.io.queued_bytes;
+
+  UNREGISTER_HANDLE_REQ(loop, handle);
+
+  if (req->wait_handle != INVALID_HANDLE_VALUE) {
+    UnregisterWait(req->wait_handle);
+    req->wait_handle = INVALID_HANDLE_VALUE;
+  }
+  if (req->event_handle) {
+    CloseHandle(req->event_handle);
+    req->event_handle = NULL;
+  }
+
+  err = GET_REQ_ERROR(req);
+
+  /* If this was a coalesced write, extract pointer to the user_provided
+   * uv_write_t structure so we can pass the expected pointer to the callback,
+   * then free the heap-allocated write req. */
+  if (req->coalesced) {
+    uv__coalesced_write_t* coalesced_write =
+        container_of(req, uv__coalesced_write_t, req);
+    req = coalesced_write->user_req;
+    uv__free(coalesced_write);
+  }
+  if (req->cb) {
+    req->cb(req, uv_translate_sys_error(err));
+  }
+
+  handle->stream.conn.write_reqs_pending--;
+
+  if (handle->flags & UV_HANDLE_NON_OVERLAPPED_PIPE &&
+      handle->pipe.conn.non_overlapped_writes_tail) {
+    assert(handle->stream.conn.write_reqs_pending > 0);
+    uv__queue_non_overlapped_write(handle);
+  }
+
+  if (handle->stream.conn.write_reqs_pending == 0 &&
+      uv__is_stream_shutting(handle))
+    uv__pipe_shutdown(loop, handle, handle->stream.conn.shutdown_req);
+
+  DECREASE_PENDING_REQ_COUNT(handle);
+}
+
+
+void uv__process_pipe_accept_req(uv_loop_t* loop, uv_pipe_t* handle,
+    uv_req_t* raw_req) {
+  uv_pipe_accept_t* req = (uv_pipe_accept_t*) raw_req;
+
+  assert(handle->type == UV_NAMED_PIPE);
+
+  if (handle->flags & UV_HANDLE_CLOSING) {
+    /* The req->pipeHandle should be freed already in uv__pipe_close(). */
+    assert(req->pipeHandle == INVALID_HANDLE_VALUE);
+    DECREASE_PENDING_REQ_COUNT(handle);
+    return;
+  }
+
+  if (REQ_SUCCESS(req)) {
+    assert(req->pipeHandle != INVALID_HANDLE_VALUE);
+    req->next_pending = handle->pipe.serv.pending_accepts;
+    handle->pipe.serv.pending_accepts = req;
+
+    if (handle->stream.serv.connection_cb) {
+      handle->stream.serv.connection_cb((uv_stream_t*)handle, 0);
+    }
+  } else {
+    if (req->pipeHandle != INVALID_HANDLE_VALUE) {
+      CloseHandle(req->pipeHandle);
+      req->pipeHandle = INVALID_HANDLE_VALUE;
+    }
+    if (!(handle->flags & UV_HANDLE_CLOSING)) {
+      uv__pipe_queue_accept(loop, handle, req, FALSE);
+    }
+  }
+
+  DECREASE_PENDING_REQ_COUNT(handle);
+}
+
+
+void uv__process_pipe_connect_req(uv_loop_t* loop, uv_pipe_t* handle,
+    uv_connect_t* req) {
+  HANDLE pipeHandle;
+  DWORD duplex_flags;
+  int err;
+
+  assert(handle->type == UV_NAMED_PIPE);
+
+  UNREGISTER_HANDLE_REQ(loop, handle);
+
+  err = 0;
+  if (REQ_SUCCESS(req)) {
+    pipeHandle = req->u.connect.pipeHandle;
+    duplex_flags = req->u.connect.duplex_flags;
+    if (handle->flags & UV_HANDLE_CLOSING)
+      err = UV_ECANCELED;
+    else
+      err = uv__set_pipe_handle(loop, handle, pipeHandle, -1, duplex_flags);
+    if (err)
+      CloseHandle(pipeHandle);
+  } else {
+    err = uv_translate_sys_error(GET_REQ_ERROR(req));
+  }
+
+  if (req->cb)
+    req->cb(req, err);
+
+  DECREASE_PENDING_REQ_COUNT(handle);
+}
+
+
+
+void uv__process_pipe_shutdown_req(uv_loop_t* loop, uv_pipe_t* handle,
+    uv_shutdown_t* req) {
+  int err;
+
+  assert(handle->type == UV_NAMED_PIPE);
+
+  /* Clear the shutdown_req field so we don't go here again. */
+  handle->stream.conn.shutdown_req = NULL;
+  UNREGISTER_HANDLE_REQ(loop, handle);
+
+  if (handle->flags & UV_HANDLE_CLOSING) {
+    /* Already closing. Cancel the shutdown. */
+    err = UV_ECANCELED;
+  } else if (!REQ_SUCCESS(req)) {
+    /* An error occurred in trying to shutdown gracefully. */
+    err = uv_translate_sys_error(GET_REQ_ERROR(req));
+  } else {
+    if (handle->flags & UV_HANDLE_READABLE) {
+      /* Initialize and optionally start the eof timer. Only do this if the pipe
+       * is readable and we haven't seen EOF come in ourselves. */
+      eof_timer_init(handle);
+
+      /* If reading start the timer right now. Otherwise uv__pipe_queue_read will
+       * start it. */
+      if (handle->flags & UV_HANDLE_READ_PENDING) {
+        eof_timer_start(handle);
+      }
+
+    } else {
+      /* This pipe is not readable. We can just close it to let the other end
+       * know that we're done writing. */
+      close_pipe(handle);
+    }
+    err = 0;
+  }
+
+  if (req->cb)
+    req->cb(req, err);
+
+  DECREASE_PENDING_REQ_COUNT(handle);
+}
+
+
+static void eof_timer_init(uv_pipe_t* pipe) {
+  int r;
+
+  assert(pipe->pipe.conn.eof_timer == NULL);
+  assert(pipe->flags & UV_HANDLE_CONNECTION);
+
+  pipe->pipe.conn.eof_timer = (uv_timer_t*) uv__malloc(sizeof *pipe->pipe.conn.eof_timer);
+
+  r = uv_timer_init(pipe->loop, pipe->pipe.conn.eof_timer);
+  assert(r == 0);  /* timers can't fail */
+  (void) r;
+  pipe->pipe.conn.eof_timer->data = pipe;
+  uv_unref((uv_handle_t*) pipe->pipe.conn.eof_timer);
+}
+
+
+static void eof_timer_start(uv_pipe_t* pipe) {
+  assert(pipe->flags & UV_HANDLE_CONNECTION);
+
+  if (pipe->pipe.conn.eof_timer != NULL) {
+    uv_timer_start(pipe->pipe.conn.eof_timer, eof_timer_cb, eof_timeout, 0);
+  }
+}
+
+
+static void eof_timer_stop(uv_pipe_t* pipe) {
+  assert(pipe->flags & UV_HANDLE_CONNECTION);
+
+  if (pipe->pipe.conn.eof_timer != NULL) {
+    uv_timer_stop(pipe->pipe.conn.eof_timer);
+  }
+}
+
+
+static void eof_timer_cb(uv_timer_t* timer) {
+  uv_pipe_t* pipe = (uv_pipe_t*) timer->data;
+  uv_loop_t* loop = timer->loop;
+
+  assert(pipe->type == UV_NAMED_PIPE);
+
+  /* This should always be true, since we start the timer only in
+   * uv__pipe_queue_read after successfully calling ReadFile, or in
+   * uv__process_pipe_shutdown_req if a read is pending, and we always
+   * immediately stop the timer in uv__process_pipe_read_req. */
+  assert(pipe->flags & UV_HANDLE_READ_PENDING);
+
+  /* If there are many packets coming off the iocp then the timer callback may
+   * be called before the read request is coming off the queue. Therefore we
+   * check here if the read request has completed but will be processed later.
+   */
+  if ((pipe->flags & UV_HANDLE_READ_PENDING) &&
+      HasOverlappedIoCompleted(&pipe->read_req.u.io.overlapped)) {
+    return;
+  }
+
+  /* Force both ends off the pipe. */
+  close_pipe(pipe);
+
+  /* Stop reading, so the pending read that is going to fail will not be
+   * reported to the user. */
+  uv_read_stop((uv_stream_t*) pipe);
+
+  /* Report the eof and update flags. This will get reported even if the user
+   * stopped reading in the meantime. TODO: is that okay? */
+  uv__pipe_read_eof(loop, pipe, uv_null_buf_);
+}
+
+
+static void eof_timer_destroy(uv_pipe_t* pipe) {
+  assert(pipe->flags & UV_HANDLE_CONNECTION);
+
+  if (pipe->pipe.conn.eof_timer) {
+    uv_close((uv_handle_t*) pipe->pipe.conn.eof_timer, eof_timer_close_cb);
+    pipe->pipe.conn.eof_timer = NULL;
+  }
+}
+
+
+static void eof_timer_close_cb(uv_handle_t* handle) {
+  assert(handle->type == UV_TIMER);
+  uv__free(handle);
+}
+
+
+int uv_pipe_open(uv_pipe_t* pipe, uv_file file) {
+  HANDLE os_handle = uv__get_osfhandle(file);
+  NTSTATUS nt_status;
+  IO_STATUS_BLOCK io_status;
+  FILE_ACCESS_INFORMATION access;
+  DWORD duplex_flags = 0;
+  int err;
+
+  if (os_handle == INVALID_HANDLE_VALUE)
+    return UV_EBADF;
+  if (pipe->flags & UV_HANDLE_PIPESERVER)
+    return UV_EINVAL;
+  if (pipe->flags & UV_HANDLE_CONNECTION)
+    return UV_EBUSY;
+
+  uv__pipe_connection_init(pipe);
+  uv__once_init();
+  /* In order to avoid closing a stdio file descriptor 0-2, duplicate the
+   * underlying OS handle and forget about the original fd.
+   * We could also opt to use the original OS handle and just never close it,
+   * but then there would be no reliable way to cancel pending read operations
+   * upon close.
+   */
+  if (file <= 2) {
+    if (!DuplicateHandle(INVALID_HANDLE_VALUE,
+                         os_handle,
+                         INVALID_HANDLE_VALUE,
+                         &os_handle,
+                         0,
+                         FALSE,
+                         DUPLICATE_SAME_ACCESS))
+      return uv_translate_sys_error(GetLastError());
+    assert(os_handle != INVALID_HANDLE_VALUE);
+    file = -1;
+  }
+
+  /* Determine what kind of permissions we have on this handle.
+   * Cygwin opens the pipe in message mode, but we can support it,
+   * just query the access flags and set the stream flags accordingly.
+   */
+  nt_status = pNtQueryInformationFile(os_handle,
+                                      &io_status,
+                                      &access,
+                                      sizeof(access),
+                                      FileAccessInformation);
+  if (nt_status != STATUS_SUCCESS)
+    return UV_EINVAL;
+
+  if (pipe->ipc) {
+    if (!(access.AccessFlags & FILE_WRITE_DATA) ||
+        !(access.AccessFlags & FILE_READ_DATA)) {
+      return UV_EINVAL;
+    }
+  }
+
+  if (access.AccessFlags & FILE_WRITE_DATA)
+    duplex_flags |= UV_HANDLE_WRITABLE;
+  if (access.AccessFlags & FILE_READ_DATA)
+    duplex_flags |= UV_HANDLE_READABLE;
+
+  err = uv__set_pipe_handle(pipe->loop,
+                            pipe,
+                            os_handle,
+                            file,
+                            duplex_flags);
+  if (err) {
+    if (file == -1)
+      CloseHandle(os_handle);
+    return err;
+  }
+
+  if (pipe->ipc) {
+    assert(!(pipe->flags & UV_HANDLE_NON_OVERLAPPED_PIPE));
+    GetNamedPipeClientProcessId(os_handle, &pipe->pipe.conn.ipc_remote_pid);
+    if (pipe->pipe.conn.ipc_remote_pid == GetCurrentProcessId()) {
+      GetNamedPipeServerProcessId(os_handle, &pipe->pipe.conn.ipc_remote_pid);
+    }
+    assert(pipe->pipe.conn.ipc_remote_pid != (DWORD)(uv_pid_t) -1);
+  }
+  return 0;
+}
+
+
+static int uv__pipe_getname(const uv_pipe_t* handle, char* buffer, size_t* size) {
+  NTSTATUS nt_status;
+  IO_STATUS_BLOCK io_status;
+  FILE_NAME_INFORMATION tmp_name_info;
+  FILE_NAME_INFORMATION* name_info;
+  WCHAR* name_buf;
+  unsigned int name_size;
+  unsigned int name_len;
+  int err;
+
+  uv__once_init();
+  name_info = NULL;
+
+  if (handle->name != NULL) {
+    /* The user might try to query the name before we are connected,
+     * and this is just easier to return the cached value if we have it. */
+    return uv__copy_utf16_to_utf8(handle->name, -1, buffer, size);
+  }
+
+  if (handle->handle == INVALID_HANDLE_VALUE) {
+    *size = 0;
+    return UV_EINVAL;
+  }
+
+  /* NtQueryInformationFile will block if another thread is performing a
+   * blocking operation on the queried handle. If the pipe handle is
+   * synchronous, there may be a worker thread currently calling ReadFile() on
+   * the pipe handle, which could cause a deadlock. To avoid this, interrupt
+   * the read. */
+  if (handle->flags & UV_HANDLE_CONNECTION &&
+      handle->flags & UV_HANDLE_NON_OVERLAPPED_PIPE) {
+    uv__pipe_interrupt_read((uv_pipe_t*) handle); /* cast away const warning */
+  }
+
+  nt_status = pNtQueryInformationFile(handle->handle,
+                                      &io_status,
+                                      &tmp_name_info,
+                                      sizeof tmp_name_info,
+                                      FileNameInformation);
+  if (nt_status == STATUS_BUFFER_OVERFLOW) {
+    name_size = sizeof(*name_info) + tmp_name_info.FileNameLength;
+    name_info = uv__malloc(name_size);
+    if (!name_info) {
+      *size = 0;
+      return UV_ENOMEM;
+    }
+
+    nt_status = pNtQueryInformationFile(handle->handle,
+                                        &io_status,
+                                        name_info,
+                                        name_size,
+                                        FileNameInformation);
+  }
+
+  if (nt_status != STATUS_SUCCESS) {
+    *size = 0;
+    err = uv_translate_sys_error(pRtlNtStatusToDosError(nt_status));
+    goto error;
+  }
+
+  if (!name_info) {
+    /* the struct on stack was used */
+    name_buf = tmp_name_info.FileName;
+    name_len = tmp_name_info.FileNameLength;
+  } else {
+    name_buf = name_info->FileName;
+    name_len = name_info->FileNameLength;
+  }
+
+  if (name_len == 0) {
+    *size = 0;
+    err = 0;
+    goto error;
+  }
+
+  name_len /= sizeof(WCHAR);
+
+  /* "\\\\.\\pipe" + name */
+  if (*size < pipe_prefix_len) {
+    *size = 0;
+  }
+  else {
+    memcpy(buffer, pipe_prefix, pipe_prefix_len);
+    *size -= pipe_prefix_len;
+  }
+  err = uv__copy_utf16_to_utf8(name_buf, name_len, buffer+pipe_prefix_len, size);
+  *size += pipe_prefix_len;
+
+error:
+  uv__free(name_info);
+  return err;
+}
+
+
+int uv_pipe_pending_count(uv_pipe_t* handle) {
+  if (!handle->ipc)
+    return 0;
+  return handle->pipe.conn.ipc_xfer_queue_length;
+}
+
+
+int uv_pipe_getsockname(const uv_pipe_t* handle, char* buffer, size_t* size) {
+  if (buffer == NULL || size == NULL || *size == 0)
+    return UV_EINVAL;
+
+  if (handle->flags & UV_HANDLE_BOUND)
+    return uv__pipe_getname(handle, buffer, size);
+
+  if (handle->flags & UV_HANDLE_CONNECTION ||
+      handle->handle != INVALID_HANDLE_VALUE) {
+    *size = 0;
+    return 0;
+  }
+
+  return UV_EBADF;
+}
+
+
+int uv_pipe_getpeername(const uv_pipe_t* handle, char* buffer, size_t* size) {
+  if (buffer == NULL || size == NULL || *size == 0)
+    return UV_EINVAL;
+
+  /* emulate unix behaviour */
+  if (handle->flags & UV_HANDLE_BOUND)
+    return UV_ENOTCONN;
+
+  if (handle->handle != INVALID_HANDLE_VALUE)
+    return uv__pipe_getname(handle, buffer, size);
+
+  if (handle->flags & UV_HANDLE_CONNECTION) {
+    if (handle->name != NULL)
+      return uv__pipe_getname(handle, buffer, size);
+  }
+
+  return UV_EBADF;
+}
+
+
+uv_handle_type uv_pipe_pending_type(uv_pipe_t* handle) {
+  if (!handle->ipc)
+    return UV_UNKNOWN_HANDLE;
+  if (handle->pipe.conn.ipc_xfer_queue_length == 0)
+    return UV_UNKNOWN_HANDLE;
+  else
+    return UV_TCP;
+}
+
+int uv_pipe_chmod(uv_pipe_t* handle, int mode) {
+  SID_IDENTIFIER_AUTHORITY sid_world = { SECURITY_WORLD_SID_AUTHORITY };
+  PACL old_dacl, new_dacl;
+  PSECURITY_DESCRIPTOR sd;
+  EXPLICIT_ACCESS ea;
+  PSID everyone;
+  int error;
+
+  if (handle == NULL || handle->handle == INVALID_HANDLE_VALUE)
+    return UV_EBADF;
+
+  if (mode != UV_READABLE &&
+      mode != UV_WRITABLE &&
+      mode != (UV_WRITABLE | UV_READABLE))
+    return UV_EINVAL;
+
+  if (!AllocateAndInitializeSid(&sid_world,
+                                1,
+                                SECURITY_WORLD_RID,
+                                0, 0, 0, 0, 0, 0, 0,
+                                &everyone)) {
+    error = GetLastError();
+    goto done;
+  }
+
+  if (GetSecurityInfo(handle->handle,
+                      SE_KERNEL_OBJECT,
+                      DACL_SECURITY_INFORMATION,
+                      NULL,
+                      NULL,
+                      &old_dacl,
+                      NULL,
+                      &sd)) {
+    error = GetLastError();
+    goto clean_sid;
+  }
+
+  memset(&ea, 0, sizeof(EXPLICIT_ACCESS));
+  if (mode & UV_READABLE)
+    ea.grfAccessPermissions |= GENERIC_READ | FILE_WRITE_ATTRIBUTES;
+  if (mode & UV_WRITABLE)
+    ea.grfAccessPermissions |= GENERIC_WRITE | FILE_READ_ATTRIBUTES;
+  ea.grfAccessPermissions |= SYNCHRONIZE;
+  ea.grfAccessMode = SET_ACCESS;
+  ea.grfInheritance = NO_INHERITANCE;
+  ea.Trustee.TrusteeForm = TRUSTEE_IS_SID;
+  ea.Trustee.TrusteeType = TRUSTEE_IS_WELL_KNOWN_GROUP;
+  ea.Trustee.ptstrName = (LPTSTR)everyone;
+
+  if (SetEntriesInAcl(1, &ea, old_dacl, &new_dacl)) {
+    error = GetLastError();
+    goto clean_sd;
+  }
+
+  if (SetSecurityInfo(handle->handle,
+                      SE_KERNEL_OBJECT,
+                      DACL_SECURITY_INFORMATION,
+                      NULL,
+                      NULL,
+                      new_dacl,
+                      NULL)) {
+    error = GetLastError();
+    goto clean_dacl;
+  }
+
+  error = 0;
+
+clean_dacl:
+  LocalFree((HLOCAL) new_dacl);
+clean_sd:
+  LocalFree((HLOCAL) sd);
+clean_sid:
+  FreeSid(everyone);
+done:
+  return uv_translate_sys_error(error);
+}