summaryrefslogtreecommitdiff
path: root/vendor/github.com/Microsoft/go-winio/pipe.go
diff options
context:
space:
mode:
Diffstat (limited to 'vendor/github.com/Microsoft/go-winio/pipe.go')
-rw-r--r--vendor/github.com/Microsoft/go-winio/pipe.go121
1 files changed, 69 insertions, 52 deletions
diff --git a/vendor/github.com/Microsoft/go-winio/pipe.go b/vendor/github.com/Microsoft/go-winio/pipe.go
index 44340b816..d99eedb64 100644
--- a/vendor/github.com/Microsoft/go-winio/pipe.go
+++ b/vendor/github.com/Microsoft/go-winio/pipe.go
@@ -15,13 +15,13 @@ import (
//sys connectNamedPipe(pipe syscall.Handle, o *syscall.Overlapped) (err error) = ConnectNamedPipe
//sys createNamedPipe(name string, flags uint32, pipeMode uint32, maxInstances uint32, outSize uint32, inSize uint32, defaultTimeout uint32, sa *syscall.SecurityAttributes) (handle syscall.Handle, err error) [failretval==syscall.InvalidHandle] = CreateNamedPipeW
//sys createFile(name string, access uint32, mode uint32, sa *syscall.SecurityAttributes, createmode uint32, attrs uint32, templatefile syscall.Handle) (handle syscall.Handle, err error) [failretval==syscall.InvalidHandle] = CreateFileW
-//sys waitNamedPipe(name string, timeout uint32) (err error) = WaitNamedPipeW
//sys getNamedPipeInfo(pipe syscall.Handle, flags *uint32, outSize *uint32, inSize *uint32, maxInstances *uint32) (err error) = GetNamedPipeInfo
//sys getNamedPipeHandleState(pipe syscall.Handle, state *uint32, curInstances *uint32, maxCollectionCount *uint32, collectDataTimeout *uint32, userName *uint16, maxUserNameSize uint32) (err error) = GetNamedPipeHandleStateW
//sys localAlloc(uFlags uint32, length uint32) (ptr uintptr) = LocalAlloc
const (
cERROR_PIPE_BUSY = syscall.Errno(231)
+ cERROR_NO_DATA = syscall.Errno(232)
cERROR_PIPE_CONNECTED = syscall.Errno(535)
cERROR_SEM_TIMEOUT = syscall.Errno(121)
@@ -120,6 +120,11 @@ func (f *win32MessageBytePipe) Read(b []byte) (int, error) {
// zero-byte message, ensure that all future Read() calls
// also return EOF.
f.readEOF = true
+ } else if err == syscall.ERROR_MORE_DATA {
+ // ERROR_MORE_DATA indicates that the pipe's read mode is message mode
+ // and the message still has more bytes. Treat this as a success, since
+ // this package presents all named pipes as byte streams.
+ err = nil
}
return n, err
}
@@ -133,12 +138,14 @@ func (s pipeAddress) String() string {
}
// DialPipe connects to a named pipe by path, timing out if the connection
-// takes longer than the specified duration. If timeout is nil, then the timeout
-// is the default timeout established by the pipe server.
+// takes longer than the specified duration. If timeout is nil, then we use
+// a default timeout of 5 seconds. (We do not use WaitNamedPipe.)
func DialPipe(path string, timeout *time.Duration) (net.Conn, error) {
var absTimeout time.Time
if timeout != nil {
absTimeout = time.Now().Add(*timeout)
+ } else {
+ absTimeout = time.Now().Add(time.Second * 2)
}
var err error
var h syscall.Handle
@@ -147,22 +154,13 @@ func DialPipe(path string, timeout *time.Duration) (net.Conn, error) {
if err != cERROR_PIPE_BUSY {
break
}
- now := time.Now()
- var ms uint32
- if absTimeout.IsZero() {
- ms = cNMPWAIT_USE_DEFAULT_WAIT
- } else if now.After(absTimeout) {
- ms = cNMPWAIT_NOWAIT
- } else {
- ms = uint32(absTimeout.Sub(now).Nanoseconds() / 1000 / 1000)
- }
- err = waitNamedPipe(path, ms)
- if err != nil {
- if err == cERROR_SEM_TIMEOUT {
- return nil, ErrTimeout
- }
- break
+ if time.Now().After(absTimeout) {
+ return nil, ErrTimeout
}
+
+ // Wait 10 msec and try again. This is a rather simplistic
+ // view, as we always try each 10 milliseconds.
+ time.Sleep(time.Millisecond * 10)
}
if err != nil {
return nil, &os.PathError{Op: "open", Path: path, Err: err}
@@ -174,16 +172,6 @@ func DialPipe(path string, timeout *time.Duration) (net.Conn, error) {
return nil, err
}
- var state uint32
- err = getNamedPipeHandleState(h, &state, nil, nil, nil, nil, 0)
- if err != nil {
- return nil, err
- }
-
- if state&cPIPE_READMODE_MESSAGE != 0 {
- return nil, &os.PathError{Op: "open", Path: path, Err: errors.New("message readmode pipes not supported")}
- }
-
f, err := makeWin32File(h)
if err != nil {
syscall.Close(h)
@@ -254,6 +242,36 @@ func (l *win32PipeListener) makeServerPipe() (*win32File, error) {
return f, nil
}
+func (l *win32PipeListener) makeConnectedServerPipe() (*win32File, error) {
+ p, err := l.makeServerPipe()
+ if err != nil {
+ return nil, err
+ }
+
+ // Wait for the client to connect.
+ ch := make(chan error)
+ go func(p *win32File) {
+ ch <- connectPipe(p)
+ }(p)
+
+ select {
+ case err = <-ch:
+ if err != nil {
+ p.Close()
+ p = nil
+ }
+ case <-l.closeCh:
+ // Abort the connect request by closing the handle.
+ p.Close()
+ p = nil
+ err = <-ch
+ if err == nil || err == ErrFileClosed {
+ err = ErrPipeListenerClosed
+ }
+ }
+ return p, err
+}
+
func (l *win32PipeListener) listenerRoutine() {
closed := false
for !closed {
@@ -261,31 +279,20 @@ func (l *win32PipeListener) listenerRoutine() {
case <-l.closeCh:
closed = true
case responseCh := <-l.acceptCh:
- p, err := l.makeServerPipe()
- if err == nil {
- // Wait for the client to connect.
- ch := make(chan error)
- go func(p *win32File) {
- ch <- connectPipe(p)
- }(p)
- select {
- case err = <-ch:
- if err != nil {
- p.Close()
- p = nil
- }
- case <-l.closeCh:
- // Abort the connect request by closing the handle.
- p.Close()
- p = nil
- err = <-ch
- if err == nil || err == ErrFileClosed {
- err = ErrPipeListenerClosed
- }
- closed = true
+ var (
+ p *win32File
+ err error
+ )
+ for {
+ p, err = l.makeConnectedServerPipe()
+ // If the connection was immediately closed by the client, try
+ // again.
+ if err != cERROR_NO_DATA {
+ break
}
}
responseCh <- acceptResponse{p, err}
+ closed = err == ErrPipeListenerClosed
}
}
syscall.Close(l.firstHandle)
@@ -334,13 +341,23 @@ func ListenPipe(path string, c *PipeConfig) (net.Listener, error) {
if err != nil {
return nil, err
}
- // Immediately open and then close a client handle so that the named pipe is
- // created but not currently accepting connections.
+ // Create a client handle and connect it. This results in the pipe
+ // instance always existing, so that clients see ERROR_PIPE_BUSY
+ // rather than ERROR_FILE_NOT_FOUND. This ties the first instance
+ // up so that no other instances can be used. This would have been
+ // cleaner if the Win32 API matched CreateFile with ConnectNamedPipe
+ // instead of CreateNamedPipe. (Apparently created named pipes are
+ // considered to be in listening state regardless of whether any
+ // active calls to ConnectNamedPipe are outstanding.)
h2, err := createFile(path, 0, 0, nil, syscall.OPEN_EXISTING, cSECURITY_SQOS_PRESENT|cSECURITY_ANONYMOUS, 0)
if err != nil {
syscall.Close(h)
return nil, err
}
+ // Close the client handle. The server side of the instance will
+ // still be busy, leading to ERROR_PIPE_BUSY instead of
+ // ERROR_NOT_FOUND, as long as we don't close the server handle,
+ // or disconnect the client with DisconnectNamedPipe.
syscall.Close(h2)
l := &win32PipeListener{
firstHandle: h,
generated by cgit v1.2.3-54-g00ecf (git 2.39.0) at 2024-10-13 01:23:16 +0000