1 // Copyright 2011 The Go Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style
3 // license that can be found in the LICENSE file.
4 5 //go:build !cgo
6 7 package fakecgo
8 9 import "unsafe"
10 11 //go:nosplit
12 //go:norace
13 func _cgo_sys_thread_start(ts *ThreadStart) {
14 var attr pthread_attr_t
15 var ign, oset sigset_t
16 var p pthread_t
17 var size size_t
18 var err int
19 20 sigfillset(&ign)
21 pthread_sigmask(SIG_SETMASK, &ign, &oset)
22 23 size = pthread_get_stacksize_np(pthread_self())
24 pthread_attr_init(&attr)
25 pthread_attr_setstacksize(&attr, size)
26 // Leave stacklo=0 and set stackhi=size; mstart will do the rest.
27 ts.g.stackhi = uintptr(size)
28 29 err = _cgo_try_pthread_create(&p, &attr, unsafe.Pointer(threadentry_trampolineABI0), ts)
30 31 pthread_sigmask(SIG_SETMASK, &oset, nil)
32 33 if err != 0 {
34 print("fakecgo: pthread_create failed: ")
35 println(err)
36 abort()
37 }
38 }
39 40 // threadentry_trampolineABI0 maps the C ABI to Go ABI then calls the Go function
41 //
42 //go:linkname x_threadentry_trampoline threadentry_trampoline
43 var x_threadentry_trampoline byte
44 var threadentry_trampolineABI0 = &x_threadentry_trampoline
45 46 //go:nosplit
47 //go:norace
48 func threadentry(v unsafe.Pointer) unsafe.Pointer {
49 ts := *(*ThreadStart)(v)
50 free(v)
51 52 setg_trampoline(setg_func, uintptr(unsafe.Pointer(ts.g)))
53 54 // faking funcs in go is a bit a... involved - but the following works :)
55 fn := uintptr(unsafe.Pointer(&ts.fn))
56 (*(*func())(unsafe.Pointer(&fn)))()
57 58 return nil
59 }
60 61 // here we will store a pointer to the provided setg func
62 var setg_func uintptr
63 64 //go:nosplit
65 //go:norace
66 func x_cgo_init(g *G, setg uintptr) {
67 var size size_t
68 69 setg_func = setg
70 71 size = pthread_get_stacksize_np(pthread_self())
72 g.stacklo = uintptr(unsafe.Add(unsafe.Pointer(&size), -size+4096))
73 }
74