diff options
Diffstat (limited to 'src/runtime/netpoll_windows.go')
-rw-r--r-- | src/runtime/netpoll_windows.go | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/src/runtime/netpoll_windows.go b/src/runtime/netpoll_windows.go new file mode 100644 index 000000000..23d5dc00f --- /dev/null +++ b/src/runtime/netpoll_windows.go @@ -0,0 +1,156 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package runtime + +import ( + "unsafe" +) + +const _DWORD_MAX = 0xffffffff + +//go:cgo_import_dynamic runtime._CreateIoCompletionPort CreateIoCompletionPort "kernel32.dll" +//go:cgo_import_dynamic runtime._GetQueuedCompletionStatus GetQueuedCompletionStatus "kernel32.dll" +//go:cgo_import_dynamic runtime._WSAGetOverlappedResult WSAGetOverlappedResult "ws2_32.dll" + +var ( + _CreateIoCompletionPort, + _GetQueuedCompletionStatus, + _WSAGetOverlappedResult stdFunction +) + +const _INVALID_HANDLE_VALUE = ^uintptr(0) + +// net_op must be the same as beginning of net.operation. Keep these in sync. +type net_op struct { + // used by windows + o overlapped + // used by netpoll + pd *pollDesc + mode int32 + errno int32 + qty uint32 +} + +type overlappedEntry struct { + key uintptr + op *net_op // In reality it's *overlapped, but we cast it to *net_op anyway. + internal uintptr + qty uint32 +} + +var iocphandle uintptr = _INVALID_HANDLE_VALUE // completion port io handle + +func netpollinit() { + iocphandle = uintptr(stdcall4(_CreateIoCompletionPort, _INVALID_HANDLE_VALUE, 0, 0, _DWORD_MAX)) + if iocphandle == 0 { + println("netpoll: failed to create iocp handle (errno=", getlasterror(), ")") + gothrow("netpoll: failed to create iocp handle") + } +} + +func netpollopen(fd uintptr, pd *pollDesc) int32 { + if stdcall4(_CreateIoCompletionPort, fd, iocphandle, 0, 0) == 0 { + return -int32(getlasterror()) + } + return 0 +} + +func netpollclose(fd uintptr) int32 { + // nothing to do + return 0 +} + +func netpollarm(pd *pollDesc, mode int) { + gothrow("unused") +} + +// Polls for completed network IO. +// Returns list of goroutines that become runnable. +func netpoll(block bool) *g { + var entries [64]overlappedEntry + var wait, qty, key, flags, n, i uint32 + var errno int32 + var op *net_op + var gp *g + + mp := getg().m + + if iocphandle == _INVALID_HANDLE_VALUE { + return nil + } + gp = nil + wait = 0 + if block { + wait = _INFINITE + } +retry: + if _GetQueuedCompletionStatusEx != nil { + n = uint32(len(entries) / int(gomaxprocs)) + if n < 8 { + n = 8 + } + if block { + mp.blocked = true + } + if stdcall6(_GetQueuedCompletionStatusEx, iocphandle, uintptr(unsafe.Pointer(&entries[0])), uintptr(n), uintptr(unsafe.Pointer(&n)), uintptr(wait), 0) == 0 { + mp.blocked = false + errno = int32(getlasterror()) + if !block && errno == _WAIT_TIMEOUT { + return nil + } + println("netpoll: GetQueuedCompletionStatusEx failed (errno=", errno, ")") + gothrow("netpoll: GetQueuedCompletionStatusEx failed") + } + mp.blocked = false + for i = 0; i < n; i++ { + op = entries[i].op + errno = 0 + qty = 0 + if stdcall5(_WSAGetOverlappedResult, op.pd.fd, uintptr(unsafe.Pointer(op)), uintptr(unsafe.Pointer(&qty)), 0, uintptr(unsafe.Pointer(&flags))) == 0 { + errno = int32(getlasterror()) + } + handlecompletion(&gp, op, errno, qty) + } + } else { + op = nil + errno = 0 + qty = 0 + if block { + mp.blocked = true + } + if stdcall5(_GetQueuedCompletionStatus, iocphandle, uintptr(unsafe.Pointer(&qty)), uintptr(unsafe.Pointer(&key)), uintptr(unsafe.Pointer(&op)), uintptr(wait)) == 0 { + mp.blocked = false + errno = int32(getlasterror()) + if !block && errno == _WAIT_TIMEOUT { + return nil + } + if op == nil { + println("netpoll: GetQueuedCompletionStatus failed (errno=", errno, ")") + gothrow("netpoll: GetQueuedCompletionStatus failed") + } + // dequeued failed IO packet, so report that + } + mp.blocked = false + handlecompletion(&gp, op, errno, qty) + } + if block && gp == nil { + goto retry + } + return gp +} + +func handlecompletion(gpp **g, op *net_op, errno int32, qty uint32) { + if op == nil { + gothrow("netpoll: GetQueuedCompletionStatus returned op == nil") + } + mode := op.mode + if mode != 'r' && mode != 'w' { + println("netpoll: GetQueuedCompletionStatus returned invalid mode=", mode) + gothrow("netpoll: GetQueuedCompletionStatus returned invalid mode") + } + op.errno = errno + op.qty = qty + netpollready((**g)(noescape(unsafe.Pointer(gpp))), op.pd, mode) +} |