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// Copyright 2016 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.
// +build aix darwin dragonfly freebsd hurd linux netbsd openbsd solaris
package runtime
import (
"unsafe"
)
// Functions for gccgo to support signal handling. In the gc runtime
// these are written in OS-specific files and in assembler.
//go:noescape
//extern sigaction
func sigaction(signum uint32, act *_sigaction, oact *_sigaction) int32
//go:noescape
//extern sigprocmask
func sigprocmask(how int32, set *sigset, oldset *sigset) int32
//go:noescape
//extern sigfillset
func sigfillset(set *sigset) int32
//go:noescape
//extern sigemptyset
func sigemptyset(set *sigset) int32
//go:noescape
//extern sigaddset
func c_sigaddset(set *sigset, signum uint32) int32
//go:noescape
//extern sigdelset
func c_sigdelset(set *sigset, signum uint32) int32
//go:noescape
//extern sigaltstack
func sigaltstack(ss *_stack_t, oss *_stack_t) int32
//extern raise
func raise(sig uint32) int32
//extern getpid
func getpid() _pid_t
//extern kill
func kill(pid _pid_t, sig uint32) int32
//go:noescape
//extern setitimer
func setitimer(which int32, new *_itimerval, old *_itimerval) int32
type sigctxt struct {
info *_siginfo_t
ctxt unsafe.Pointer
}
func (c *sigctxt) sigcode() uint64 {
return uint64(getSiginfoCode(c.info))
}
//go:nosplit
//go:nowritebarrierrec
func setsig(i uint32, fn uintptr) {
var sa _sigaction
sa.sa_flags = _SA_SIGINFO | _SA_RESTART
// For gccgo we do not set SA_ONSTACK for a signal that can
// cause a panic. Instead, we trust that the split stack has
// enough room to start the signal handler. This is because
// otherwise we have no good way to switch back to the
// original stack before panicing.
if sigtable[i].flags&_SigPanic == 0 {
sa.sa_flags |= _SA_ONSTACK
}
sigfillset((*sigset)(unsafe.Pointer(&sa.sa_mask)))
setSigactionHandler(&sa, fn)
sigaction(i, &sa, nil)
}
//go:nosplit
//go:nowritebarrierrec
func setsigstack(i uint32) {
var sa _sigaction
sigaction(i, nil, &sa)
handler := getSigactionHandler(&sa)
if handler == 0 || handler == _SIG_DFL || handler == _SIG_IGN || sa.sa_flags&_SA_ONSTACK != 0 {
return
}
if sigtable[i].flags&_SigPanic != 0 {
return
}
sa.sa_flags |= _SA_ONSTACK
sigaction(i, &sa, nil)
}
//go:nosplit
//go:nowritebarrierrec
func getsig(i uint32) uintptr {
var sa _sigaction
if sigaction(i, nil, &sa) < 0 {
// On GNU/Linux glibc rejects attempts to call
// sigaction with signal 32 (SIGCANCEL) or 33 (SIGSETXID).
if GOOS == "linux" && (i == 32 || i == 33) {
return _SIG_DFL
}
throw("sigaction read failure")
}
return getSigactionHandler(&sa)
}
func signalstack(p unsafe.Pointer, n uintptr)
//go:nosplit
//go:nowritebarrierrec
func raiseproc(sig uint32) {
kill(getpid(), sig)
}
//go:nosplit
//go:nowritebarrierrec
func sigfwd(fn uintptr, sig uint32, info *_siginfo_t, ctx unsafe.Pointer) {
f1 := [1]uintptr{fn}
f2 := &f1
f3 := *(*func(uint32, *_siginfo_t, unsafe.Pointer))(unsafe.Pointer(&f2))
f3(sig, info, ctx)
}
//go:nosplit
//go:nowritebarrierrec
func sigaddset(mask *sigset, i int) {
c_sigaddset(mask, uint32(i))
}
func sigdelset(mask *sigset, i int) {
c_sigdelset(mask, uint32(i))
}
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