rpc: migrated the RPC insterface to a new reflection based RPC layer

1 files changed, 655 insertions, 0 deletions

diff --git a/rpc/ipc_windows.go b/rpc/ipc_windows.go
new file mode 100644
index 000000000..1d4672ad2
--- /dev/null
+++ b/rpc/ipc_windows.go
@@ -0,0 +1,655 @@
+// Copyright 2015 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+// +build windows
+
+package rpc
+
+import (
+	"fmt"
+	"io"
+	"net"
+	"sync"
+	"syscall"
+	"time"
+	"unsafe"
+)
+
+var (
+	modkernel32 = syscall.NewLazyDLL("kernel32.dll")
+
+	procCreateNamedPipeW    = modkernel32.NewProc("CreateNamedPipeW")
+	procConnectNamedPipe    = modkernel32.NewProc("ConnectNamedPipe")
+	procDisconnectNamedPipe = modkernel32.NewProc("DisconnectNamedPipe")
+	procWaitNamedPipeW      = modkernel32.NewProc("WaitNamedPipeW")
+	procCreateEventW        = modkernel32.NewProc("CreateEventW")
+	procGetOverlappedResult = modkernel32.NewProc("GetOverlappedResult")
+	procCancelIoEx          = modkernel32.NewProc("CancelIoEx")
+)
+
+func createNamedPipe(name *uint16, openMode uint32, pipeMode uint32, maxInstances uint32, outBufSize uint32, inBufSize uint32, defaultTimeout uint32, sa *syscall.SecurityAttributes) (handle syscall.Handle, err error) {
+	r0, _, e1 := syscall.Syscall9(procCreateNamedPipeW.Addr(), 8, uintptr(unsafe.Pointer(name)), uintptr(openMode), uintptr(pipeMode), uintptr(maxInstances), uintptr(outBufSize), uintptr(inBufSize), uintptr(defaultTimeout), uintptr(unsafe.Pointer(sa)), 0)
+	handle = syscall.Handle(r0)
+	if handle == syscall.InvalidHandle {
+		if e1 != 0 {
+			err = error(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func cancelIoEx(handle syscall.Handle, overlapped *syscall.Overlapped) (err error) {
+	r1, _, e1 := syscall.Syscall(procCancelIoEx.Addr(), 2, uintptr(handle), uintptr(unsafe.Pointer(overlapped)), 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = error(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func connectNamedPipe(handle syscall.Handle, overlapped *syscall.Overlapped) (err error) {
+	r1, _, e1 := syscall.Syscall(procConnectNamedPipe.Addr(), 2, uintptr(handle), uintptr(unsafe.Pointer(overlapped)), 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = error(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func disconnectNamedPipe(handle syscall.Handle) (err error) {
+	r1, _, e1 := syscall.Syscall(procDisconnectNamedPipe.Addr(), 1, uintptr(handle), 0, 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = error(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func waitNamedPipe(name *uint16, timeout uint32) (err error) {
+	r1, _, e1 := syscall.Syscall(procWaitNamedPipeW.Addr(), 2, uintptr(unsafe.Pointer(name)), uintptr(timeout), 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = error(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func createEvent(sa *syscall.SecurityAttributes, manualReset bool, initialState bool, name *uint16) (handle syscall.Handle, err error) {
+	var _p0 uint32
+	if manualReset {
+		_p0 = 1
+	} else {
+		_p0 = 0
+	}
+	var _p1 uint32
+	if initialState {
+		_p1 = 1
+	} else {
+		_p1 = 0
+	}
+	r0, _, e1 := syscall.Syscall6(procCreateEventW.Addr(), 4, uintptr(unsafe.Pointer(sa)), uintptr(_p0), uintptr(_p1), uintptr(unsafe.Pointer(name)), 0, 0)
+	handle = syscall.Handle(r0)
+	if handle == syscall.InvalidHandle {
+		if e1 != 0 {
+			err = error(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func getOverlappedResult(handle syscall.Handle, overlapped *syscall.Overlapped, transferred *uint32, wait bool) (err error) {
+	var _p0 uint32
+	if wait {
+		_p0 = 1
+	} else {
+		_p0 = 0
+	}
+	r1, _, e1 := syscall.Syscall6(procGetOverlappedResult.Addr(), 4, uintptr(handle), uintptr(unsafe.Pointer(overlapped)), uintptr(unsafe.Pointer(transferred)), uintptr(_p0), 0, 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = error(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+const (
+	// openMode
+	pipe_access_duplex   = 0x3
+	pipe_access_inbound  = 0x1
+	pipe_access_outbound = 0x2
+
+	// openMode write flags
+	file_flag_first_pipe_instance = 0x00080000
+	file_flag_write_through       = 0x80000000
+	file_flag_overlapped          = 0x40000000
+
+	// openMode ACL flags
+	write_dac              = 0x00040000
+	write_owner            = 0x00080000
+	access_system_security = 0x01000000
+
+	// pipeMode
+	pipe_type_byte    = 0x0
+	pipe_type_message = 0x4
+
+	// pipeMode read mode flags
+	pipe_readmode_byte    = 0x0
+	pipe_readmode_message = 0x2
+
+	// pipeMode wait mode flags
+	pipe_wait   = 0x0
+	pipe_nowait = 0x1
+
+	// pipeMode remote-client mode flags
+	pipe_accept_remote_clients = 0x0
+	pipe_reject_remote_clients = 0x8
+
+	pipe_unlimited_instances = 255
+
+	nmpwait_wait_forever = 0xFFFFFFFF
+
+	// the two not-an-errors below occur if a client connects to the pipe between
+	// the server's CreateNamedPipe and ConnectNamedPipe calls.
+	error_no_data        syscall.Errno = 0xE8
+	error_pipe_connected syscall.Errno = 0x217
+	error_pipe_busy      syscall.Errno = 0xE7
+	error_sem_timeout    syscall.Errno = 0x79
+
+	error_bad_pathname syscall.Errno = 0xA1
+	error_invalid_name syscall.Errno = 0x7B
+
+	error_io_incomplete syscall.Errno = 0x3e4
+)
+
+var _ net.Conn = (*PipeConn)(nil)
+var _ net.Listener = (*PipeListener)(nil)
+
+// ErrClosed is the error returned by PipeListener.Accept when Close is called
+// on the PipeListener.
+var ErrClosed = PipeError{"Pipe has been closed.", false}
+
+// PipeError is an error related to a call to a pipe
+type PipeError struct {
+	msg     string
+	timeout bool
+}
+
+// Error implements the error interface
+func (e PipeError) Error() string {
+	return e.msg
+}
+
+// Timeout implements net.AddrError.Timeout()
+func (e PipeError) Timeout() bool {
+	return e.timeout
+}
+
+// Temporary implements net.AddrError.Temporary()
+func (e PipeError) Temporary() bool {
+	return false
+}
+
+// Dial connects to a named pipe with the given address. If the specified pipe is not available,
+// it will wait indefinitely for the pipe to become available.
+//
+// The address must be of the form \\.\\pipe\<name> for local pipes and \\<computer>\pipe\<name>
+// for remote pipes.
+//
+// Dial will return a PipeError if you pass in a badly formatted pipe name.
+//
+// Examples:
+//   // local pipe
+//   conn, err := Dial(`\\.\pipe\mypipename`)
+//
+//   // remote pipe
+//   conn, err := Dial(`\\othercomp\pipe\mypipename`)
+func Dial(address string) (*PipeConn, error) {
+	for {
+		conn, err := dial(address, nmpwait_wait_forever)
+		if err == nil {
+			return conn, nil
+		}
+		if isPipeNotReady(err) {
+			<-time.After(100 * time.Millisecond)
+			continue
+		}
+		return nil, err
+	}
+}
+
+// DialTimeout acts like Dial, but will time out after the duration of timeout
+func DialTimeout(address string, timeout time.Duration) (*PipeConn, error) {
+	deadline := time.Now().Add(timeout)
+
+	now := time.Now()
+	for now.Before(deadline) {
+		millis := uint32(deadline.Sub(now) / time.Millisecond)
+		conn, err := dial(address, millis)
+		if err == nil {
+			return conn, nil
+		}
+		if err == error_sem_timeout {
+			// This is WaitNamedPipe's timeout error, so we know we're done
+			return nil, PipeError{fmt.Sprintf(
+				"Timed out waiting for pipe '%s' to come available", address), true}
+		}
+		if isPipeNotReady(err) {
+			left := deadline.Sub(time.Now())
+			retry := 100 * time.Millisecond
+			if left > retry {
+				<-time.After(retry)
+			} else {
+				<-time.After(left - time.Millisecond)
+			}
+			now = time.Now()
+			continue
+		}
+		return nil, err
+	}
+	return nil, PipeError{fmt.Sprintf(
+		"Timed out waiting for pipe '%s' to come available", address), true}
+}
+
+// isPipeNotReady checks the error to see if it indicates the pipe is not ready
+func isPipeNotReady(err error) bool {
+	// Pipe Busy means another client just grabbed the open pipe end,
+	// and the server hasn't made a new one yet.
+	// File Not Found means the server hasn't created the pipe yet.
+	// Neither is a fatal error.
+
+	return err == syscall.ERROR_FILE_NOT_FOUND || err == error_pipe_busy
+}
+
+// newOverlapped creates a structure used to track asynchronous
+// I/O requests that have been issued.
+func newOverlapped() (*syscall.Overlapped, error) {
+	event, err := createEvent(nil, true, true, nil)
+	if err != nil {
+		return nil, err
+	}
+	return &syscall.Overlapped{HEvent: event}, nil
+}
+
+// waitForCompletion waits for an asynchronous I/O request referred to by overlapped to complete.
+// This function returns the number of bytes transferred by the operation and an error code if
+// applicable (nil otherwise).
+func waitForCompletion(handle syscall.Handle, overlapped *syscall.Overlapped) (uint32, error) {
+	_, err := syscall.WaitForSingleObject(overlapped.HEvent, syscall.INFINITE)
+	if err != nil {
+		return 0, err
+	}
+	var transferred uint32
+	err = getOverlappedResult(handle, overlapped, &transferred, true)
+	return transferred, err
+}
+
+// dial is a helper to initiate a connection to a named pipe that has been started by a server.
+// The timeout is only enforced if the pipe server has already created the pipe, otherwise
+// this function will return immediately.
+func dial(address string, timeout uint32) (*PipeConn, error) {
+	name, err := syscall.UTF16PtrFromString(string(address))
+	if err != nil {
+		return nil, err
+	}
+	// If at least one instance of the pipe has been created, this function
+	// will wait timeout milliseconds for it to become available.
+	// It will return immediately regardless of timeout, if no instances
+	// of the named pipe have been created yet.
+	// If this returns with no error, there is a pipe available.
+	if err := waitNamedPipe(name, timeout); err != nil {
+		if err == error_bad_pathname {
+			// badly formatted pipe name
+			return nil, badAddr(address)
+		}
+		return nil, err
+	}
+	pathp, err := syscall.UTF16PtrFromString(address)
+	if err != nil {
+		return nil, err
+	}
+	handle, err := syscall.CreateFile(pathp, syscall.GENERIC_READ|syscall.GENERIC_WRITE,
+		uint32(syscall.FILE_SHARE_READ|syscall.FILE_SHARE_WRITE), nil, syscall.OPEN_EXISTING,
+		syscall.FILE_FLAG_OVERLAPPED, 0)
+	if err != nil {
+		return nil, err
+	}
+	return &PipeConn{handle: handle, addr: PipeAddr(address)}, nil
+}
+
+// Listen returns a new PipeListener that will listen on a pipe with the given
+// address. The address must be of the form \\.\pipe\<name>
+//
+// Listen will return a PipeError for an incorrectly formatted pipe name.
+func Listen(address string) (*PipeListener, error) {
+	handle, err := createPipe(address, true)
+	if err == error_invalid_name {
+		return nil, badAddr(address)
+	}
+	if err != nil {
+		return nil, err
+	}
+	return &PipeListener{
+		addr:   PipeAddr(address),
+		handle: handle,
+	}, nil
+}
+
+// PipeListener is a named pipe listener. Clients should typically
+// use variables of type net.Listener instead of assuming named pipe.
+type PipeListener struct {
+	addr   PipeAddr
+	handle syscall.Handle
+	closed bool
+
+	// acceptHandle contains the current handle waiting for
+	// an incoming connection or nil.
+	acceptHandle syscall.Handle
+	// acceptOverlapped is set before waiting on a connection.
+	// If not waiting, it is nil.
+	acceptOverlapped *syscall.Overlapped
+	// acceptMutex protects the handle and overlapped structure.
+	acceptMutex sync.Mutex
+}
+
+// Accept implements the Accept method in the net.Listener interface; it
+// waits for the next call and returns a generic net.Conn.
+func (l *PipeListener) Accept() (net.Conn, error) {
+	c, err := l.AcceptPipe()
+	for err == error_no_data {
+		// Ignore clients that connect and immediately disconnect.
+		c, err = l.AcceptPipe()
+	}
+	if err != nil {
+		return nil, err
+	}
+	return c, nil
+}
+
+// AcceptPipe accepts the next incoming call and returns the new connection.
+// It might return an error if a client connected and immediately cancelled
+// the connection.
+func (l *PipeListener) AcceptPipe() (*PipeConn, error) {
+	if l == nil || l.addr == "" || l.closed {
+		return nil, syscall.EINVAL
+	}
+
+	// the first time we call accept, the handle will have been created by the Listen
+	// call. This is to prevent race conditions where the client thinks the server
+	// isn't listening because it hasn't actually called create yet. After the first time, we'll
+	// have to create a new handle each time
+	handle := l.handle
+	if handle == 0 {
+		var err error
+		handle, err = createPipe(string(l.addr), false)
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		l.handle = 0
+	}
+
+	overlapped, err := newOverlapped()
+	if err != nil {
+		return nil, err
+	}
+	defer syscall.CloseHandle(overlapped.HEvent)
+	if err := connectNamedPipe(handle, overlapped); err != nil && err != error_pipe_connected {
+		if err == error_io_incomplete || err == syscall.ERROR_IO_PENDING {
+			l.acceptMutex.Lock()
+			l.acceptOverlapped = overlapped
+			l.acceptHandle = handle
+			l.acceptMutex.Unlock()
+			defer func() {
+				l.acceptMutex.Lock()
+				l.acceptOverlapped = nil
+				l.acceptHandle = 0
+				l.acceptMutex.Unlock()
+			}()
+
+			_, err = waitForCompletion(handle, overlapped)
+		}
+		if err == syscall.ERROR_OPERATION_ABORTED {
+			// Return error compatible to net.Listener.Accept() in case the
+			// listener was closed.
+			return nil, ErrClosed
+		}
+		if err != nil {
+			return nil, err
+		}
+	}
+	return &PipeConn{handle: handle, addr: l.addr}, nil
+}
+
+// Close stops listening on the address.
+// Already Accepted connections are not closed.
+func (l *PipeListener) Close() error {
+	if l.closed {
+		return nil
+	}
+	l.closed = true
+	if l.handle != 0 {
+		err := disconnectNamedPipe(l.handle)
+		if err != nil {
+			return err
+		}
+		err = syscall.CloseHandle(l.handle)
+		if err != nil {
+			return err
+		}
+		l.handle = 0
+	}
+	l.acceptMutex.Lock()
+	defer l.acceptMutex.Unlock()
+	if l.acceptOverlapped != nil && l.acceptHandle != 0 {
+		// Cancel the pending IO. This call does not block, so it is safe
+		// to hold onto the mutex above.
+		if err := cancelIoEx(l.acceptHandle, l.acceptOverlapped); err != nil {
+			return err
+		}
+		err := syscall.CloseHandle(l.acceptOverlapped.HEvent)
+		if err != nil {
+			return err
+		}
+		l.acceptOverlapped.HEvent = 0
+		err = syscall.CloseHandle(l.acceptHandle)
+		if err != nil {
+			return err
+		}
+		l.acceptHandle = 0
+	}
+	return nil
+}
+
+// Addr returns the listener's network address, a PipeAddr.
+func (l *PipeListener) Addr() net.Addr { return l.addr }
+
+// PipeConn is the implementation of the net.Conn interface for named pipe connections.
+type PipeConn struct {
+	handle syscall.Handle
+	addr   PipeAddr
+
+	// these aren't actually used yet
+	readDeadline  *time.Time
+	writeDeadline *time.Time
+}
+
+type iodata struct {
+	n   uint32
+	err error
+}
+
+// completeRequest looks at iodata to see if a request is pending. If so, it waits for it to either complete or to
+// abort due to hitting the specified deadline. Deadline may be set to nil to wait forever. If no request is pending,
+// the content of iodata is returned.
+func (c *PipeConn) completeRequest(data iodata, deadline *time.Time, overlapped *syscall.Overlapped) (int, error) {
+	if data.err == error_io_incomplete || data.err == syscall.ERROR_IO_PENDING {
+		var timer <-chan time.Time
+		if deadline != nil {
+			if timeDiff := deadline.Sub(time.Now()); timeDiff > 0 {
+				timer = time.After(timeDiff)
+			}
+		}
+		done := make(chan iodata)
+		go func() {
+			n, err := waitForCompletion(c.handle, overlapped)
+			done <- iodata{n, err}
+		}()
+		select {
+		case data = <-done:
+		case <-timer:
+			syscall.CancelIoEx(c.handle, overlapped)
+			data = iodata{0, timeout(c.addr.String())}
+		}
+	}
+	// Windows will produce ERROR_BROKEN_PIPE upon closing
+	// a handle on the other end of a connection. Go RPC
+	// expects an io.EOF error in this case.
+	if data.err == syscall.ERROR_BROKEN_PIPE {
+		data.err = io.EOF
+	}
+	return int(data.n), data.err
+}
+
+// Read implements the net.Conn Read method.
+func (c *PipeConn) Read(b []byte) (int, error) {
+	// Use ReadFile() rather than Read() because the latter
+	// contains a workaround that eats ERROR_BROKEN_PIPE.
+	overlapped, err := newOverlapped()
+	if err != nil {
+		return 0, err
+	}
+	defer syscall.CloseHandle(overlapped.HEvent)
+	var n uint32
+	err = syscall.ReadFile(c.handle, b, &n, overlapped)
+	return c.completeRequest(iodata{n, err}, c.readDeadline, overlapped)
+}
+
+// Write implements the net.Conn Write method.
+func (c *PipeConn) Write(b []byte) (int, error) {
+	overlapped, err := newOverlapped()
+	if err != nil {
+		return 0, err
+	}
+	defer syscall.CloseHandle(overlapped.HEvent)
+	var n uint32
+	err = syscall.WriteFile(c.handle, b, &n, overlapped)
+	return c.completeRequest(iodata{n, err}, c.writeDeadline, overlapped)
+}
+
+// Close closes the connection.
+func (c *PipeConn) Close() error {
+	return syscall.CloseHandle(c.handle)
+}
+
+// LocalAddr returns the local network address.
+func (c *PipeConn) LocalAddr() net.Addr {
+	return c.addr
+}
+
+// RemoteAddr returns the remote network address.
+func (c *PipeConn) RemoteAddr() net.Addr {
+	// not sure what to do here, we don't have remote addr....
+	return c.addr
+}
+
+// SetDeadline implements the net.Conn SetDeadline method.
+// Note that timeouts are only supported on Windows Vista/Server 2008 and above
+func (c *PipeConn) SetDeadline(t time.Time) error {
+	c.SetReadDeadline(t)
+	c.SetWriteDeadline(t)
+	return nil
+}
+
+// SetReadDeadline implements the net.Conn SetReadDeadline method.
+// Note that timeouts are only supported on Windows Vista/Server 2008 and above
+func (c *PipeConn) SetReadDeadline(t time.Time) error {
+	c.readDeadline = &t
+	return nil
+}
+
+// SetWriteDeadline implements the net.Conn SetWriteDeadline method.
+// Note that timeouts are only supported on Windows Vista/Server 2008 and above
+func (c *PipeConn) SetWriteDeadline(t time.Time) error {
+	c.writeDeadline = &t
+	return nil
+}
+
+// PipeAddr represents the address of a named pipe.
+type PipeAddr string
+
+// Network returns the address's network name, "pipe".
+func (a PipeAddr) Network() string { return "pipe" }
+
+// String returns the address of the pipe
+func (a PipeAddr) String() string {
+	return string(a)
+}
+
+// createPipe is a helper function to make sure we always create pipes
+// with the same arguments, since subsequent calls to create pipe need
+// to use the same arguments as the first one. If first is set, fail
+// if the pipe already exists.
+func createPipe(address string, first bool) (syscall.Handle, error) {
+	n, err := syscall.UTF16PtrFromString(address)
+	if err != nil {
+		return 0, err
+	}
+	mode := uint32(pipe_access_duplex | syscall.FILE_FLAG_OVERLAPPED)
+	if first {
+		mode |= file_flag_first_pipe_instance
+	}
+	return createNamedPipe(n,
+		mode,
+		pipe_type_byte,
+		pipe_unlimited_instances,
+		512, 512, 0, nil)
+}
+
+func badAddr(addr string) PipeError {
+	return PipeError{fmt.Sprintf("Invalid pipe address '%s'.", addr), false}
+}
+func timeout(addr string) PipeError {
+	return PipeError{fmt.Sprintf("Pipe IO timed out waiting for '%s'", addr), true}
+}
+
+// ipcListen will create a named pipe on the given endpoint.
+func ipcListen(endpoint string) (net.Listener, error) {
+	return Listen(endpoint)
+}
+
+// newIPCConnection will connect to a named pipe with the given endpoint as name.
+func newIPCConnection(endpoint string) (net.Conn, error) {
+	return Dial(endpoint)
+}