blob: f3cd15c7a95372091da437fb3e6a2bff28e2cfc2 [file] [log] [blame]
// 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.
#include "runtime.h"
#include "defs_GOOS_GOARCH.h"
#include "os_GOOS.h"
#define DWORD_MAX 0xffffffff
#pragma dynimport runtime·CreateIoCompletionPort CreateIoCompletionPort "kernel32.dll"
#pragma dynimport runtime·GetQueuedCompletionStatus GetQueuedCompletionStatus "kernel32.dll"
#pragma dynimport runtime·WSAGetOverlappedResult WSAGetOverlappedResult "ws2_32.dll"
extern void *runtime·CreateIoCompletionPort;
extern void *runtime·GetQueuedCompletionStatus;
extern void *runtime·WSAGetOverlappedResult;
#define INVALID_HANDLE_VALUE ((uintptr)-1)
// net_op must be the same as beginning of net.operation. Keep these in sync.
typedef struct net_op net_op;
struct net_op
{
// used by windows
Overlapped o;
// used by netpoll
PollDesc* pd;
int32 mode;
int32 errno;
uint32 qty;
};
typedef struct OverlappedEntry OverlappedEntry;
struct OverlappedEntry
{
uintptr key;
net_op* op; // In reality it's Overlapped*, but we cast it to net_op* anyway.
uintptr internal;
uint32 qty;
};
static void handlecompletion(G **gpp, net_op *o, int32 errno, uint32 qty);
static uintptr iocphandle = INVALID_HANDLE_VALUE; // completion port io handle
void
runtime·netpollinit(void)
{
iocphandle = (uintptr)runtime·stdcall(runtime·CreateIoCompletionPort, 4, INVALID_HANDLE_VALUE, (uintptr)0, (uintptr)0, (uintptr)DWORD_MAX);
if(iocphandle == 0) {
runtime·printf("netpoll: failed to create iocp handle (errno=%d)\n", runtime·getlasterror());
runtime·throw("netpoll: failed to create iocp handle");
}
return;
}
int32
runtime·netpollopen(uintptr fd, PollDesc *pd)
{
USED(pd);
if(runtime·stdcall(runtime·CreateIoCompletionPort, 4, fd, iocphandle, (uintptr)0, (uintptr)0) == 0)
return -runtime·getlasterror();
return 0;
}
int32
runtime·netpollclose(uintptr fd)
{
// nothing to do
USED(fd);
return 0;
}
void
runtime·netpollarm(PollDesc* pd, int32 mode)
{
USED(pd, mode);
runtime·throw("unused");
}
// Polls for completed network IO.
// Returns list of goroutines that become runnable.
G*
runtime·netpoll(bool block)
{
OverlappedEntry entries[64];
uint32 wait, qty, key, flags, n, i;
int32 errno;
net_op *op;
G *gp;
if(iocphandle == INVALID_HANDLE_VALUE)
return nil;
gp = nil;
wait = 0;
if(block)
wait = INFINITE;
retry:
if(runtime·GetQueuedCompletionStatusEx != nil) {
n = nelem(entries) / runtime·gomaxprocs;
if(n < 8)
n = 8;
if(block)
m->blocked = true;
if(runtime·stdcall(runtime·GetQueuedCompletionStatusEx, 6, iocphandle, entries, (uintptr)n, &n, (uintptr)wait, (uintptr)0) == 0) {
m->blocked = false;
errno = runtime·getlasterror();
if(!block && errno == WAIT_TIMEOUT)
return nil;
runtime·printf("netpoll: GetQueuedCompletionStatusEx failed (errno=%d)\n", errno);
runtime·throw("netpoll: GetQueuedCompletionStatusEx failed");
}
m->blocked = false;
for(i = 0; i < n; i++) {
op = entries[i].op;
errno = 0;
qty = 0;
if(runtime·stdcall(runtime·WSAGetOverlappedResult, 5, runtime·netpollfd(op->pd), op, &qty, (uintptr)0, (uintptr)&flags) == 0)
errno = runtime·getlasterror();
handlecompletion(&gp, op, errno, qty);
}
} else {
op = nil;
errno = 0;
qty = 0;
if(block)
m->blocked = true;
if(runtime·stdcall(runtime·GetQueuedCompletionStatus, 5, iocphandle, &qty, &key, &op, (uintptr)wait) == 0) {
m->blocked = false;
errno = runtime·getlasterror();
if(!block && errno == WAIT_TIMEOUT)
return nil;
if(op == nil) {
runtime·printf("netpoll: GetQueuedCompletionStatus failed (errno=%d)\n", errno);
runtime·throw("netpoll: GetQueuedCompletionStatus failed");
}
// dequeued failed IO packet, so report that
}
m->blocked = false;
handlecompletion(&gp, op, errno, qty);
}
if(block && gp == nil)
goto retry;
return gp;
}
static void
handlecompletion(G **gpp, net_op *op, int32 errno, uint32 qty)
{
int32 mode;
if(op == nil)
runtime·throw("netpoll: GetQueuedCompletionStatus returned op == nil");
mode = op->mode;
if(mode != 'r' && mode != 'w') {
runtime·printf("netpoll: GetQueuedCompletionStatus returned invalid mode=%d\n", mode);
runtime·throw("netpoll: GetQueuedCompletionStatus returned invalid mode");
}
op->errno = errno;
op->qty = qty;
runtime·netpollready(gpp, op->pd, mode);
}