1 files changed, 326 insertions, 0 deletions
diff --git a/src/runtime/signal_windows.go b/src/runtime/signal_windows.go
new file mode 100644
index 0000000..c5cf38c
--- /dev/null
+++ b/src/runtime/signal_windows.go
@@ -0,0 +1,326 @@
+// Copyright 2011 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 (
+	"internal/abi"
+	"runtime/internal/sys"
+	"unsafe"
+)
+
+func disableWER() {
+	// do not display Windows Error Reporting dialogue
+	const (
+		SEM_FAILCRITICALERRORS     = 0x0001
+		SEM_NOGPFAULTERRORBOX      = 0x0002
+		SEM_NOALIGNMENTFAULTEXCEPT = 0x0004
+		SEM_NOOPENFILEERRORBOX     = 0x8000
+	)
+	errormode := uint32(stdcall1(_SetErrorMode, SEM_NOGPFAULTERRORBOX))
+	stdcall1(_SetErrorMode, uintptr(errormode)|SEM_FAILCRITICALERRORS|SEM_NOGPFAULTERRORBOX|SEM_NOOPENFILEERRORBOX)
+}
+
+// in sys_windows_386.s and sys_windows_amd64.s
+func exceptiontramp()
+func firstcontinuetramp()
+func lastcontinuetramp()
+
+func initExceptionHandler() {
+	stdcall2(_AddVectoredExceptionHandler, 1, abi.FuncPCABI0(exceptiontramp))
+	if _AddVectoredContinueHandler == nil || GOARCH == "386" {
+		// use SetUnhandledExceptionFilter for windows-386 or
+		// if VectoredContinueHandler is unavailable.
+		// note: SetUnhandledExceptionFilter handler won't be called, if debugging.
+		stdcall1(_SetUnhandledExceptionFilter, abi.FuncPCABI0(lastcontinuetramp))
+	} else {
+		stdcall2(_AddVectoredContinueHandler, 1, abi.FuncPCABI0(firstcontinuetramp))
+		stdcall2(_AddVectoredContinueHandler, 0, abi.FuncPCABI0(lastcontinuetramp))
+	}
+}
+
+// isAbort returns true, if context r describes exception raised
+// by calling runtime.abort function.
+//
+//go:nosplit
+func isAbort(r *context) bool {
+	pc := r.ip()
+	if GOARCH == "386" || GOARCH == "amd64" || GOARCH == "arm" {
+		// In the case of an abort, the exception IP is one byte after
+		// the INT3 (this differs from UNIX OSes). Note that on ARM,
+		// this means that the exception IP is no longer aligned.
+		pc--
+	}
+	return isAbortPC(pc)
+}
+
+// isgoexception reports whether this exception should be translated
+// into a Go panic or throw.
+//
+// It is nosplit to avoid growing the stack in case we're aborting
+// because of a stack overflow.
+//
+//go:nosplit
+func isgoexception(info *exceptionrecord, r *context) bool {
+	// Only handle exception if executing instructions in Go binary
+	// (not Windows library code).
+	// TODO(mwhudson): needs to loop to support shared libs
+	if r.ip() < firstmoduledata.text || firstmoduledata.etext < r.ip() {
+		return false
+	}
+
+	// Go will only handle some exceptions.
+	switch info.exceptioncode {
+	default:
+		return false
+	case _EXCEPTION_ACCESS_VIOLATION:
+	case _EXCEPTION_INT_DIVIDE_BY_ZERO:
+	case _EXCEPTION_INT_OVERFLOW:
+	case _EXCEPTION_FLT_DENORMAL_OPERAND:
+	case _EXCEPTION_FLT_DIVIDE_BY_ZERO:
+	case _EXCEPTION_FLT_INEXACT_RESULT:
+	case _EXCEPTION_FLT_OVERFLOW:
+	case _EXCEPTION_FLT_UNDERFLOW:
+	case _EXCEPTION_BREAKPOINT:
+	case _EXCEPTION_ILLEGAL_INSTRUCTION: // breakpoint arrives this way on arm64
+	}
+	return true
+}
+
+// Called by sigtramp from Windows VEH handler.
+// Return value signals whether the exception has been handled (EXCEPTION_CONTINUE_EXECUTION)
+// or should be made available to other handlers in the chain (EXCEPTION_CONTINUE_SEARCH).
+//
+// This is the first entry into Go code for exception handling. This
+// is nosplit to avoid growing the stack until we've checked for
+// _EXCEPTION_BREAKPOINT, which is raised if we overflow the g0 stack,
+//
+//go:nosplit
+func exceptionhandler(info *exceptionrecord, r *context, gp *g) int32 {
+	if !isgoexception(info, r) {
+		return _EXCEPTION_CONTINUE_SEARCH
+	}
+
+	if gp.throwsplit || isAbort(r) {
+		// We can't safely sigpanic because it may grow the stack.
+		// Or this is a call to abort.
+		// Don't go through any more of the Windows handler chain.
+		// Crash now.
+		winthrow(info, r, gp)
+	}
+
+	// After this point, it is safe to grow the stack.
+
+	// Make it look like a call to the signal func.
+	// Have to pass arguments out of band since
+	// augmenting the stack frame would break
+	// the unwinding code.
+	gp.sig = info.exceptioncode
+	gp.sigcode0 = info.exceptioninformation[0]
+	gp.sigcode1 = info.exceptioninformation[1]
+	gp.sigpc = r.ip()
+
+	// Only push runtime·sigpanic if r.ip() != 0.
+	// If r.ip() == 0, probably panicked because of a
+	// call to a nil func. Not pushing that onto sp will
+	// make the trace look like a call to runtime·sigpanic instead.
+	// (Otherwise the trace will end at runtime·sigpanic and we
+	// won't get to see who faulted.)
+	// Also don't push a sigpanic frame if the faulting PC
+	// is the entry of asyncPreempt. In this case, we suspended
+	// the thread right between the fault and the exception handler
+	// starting to run, and we have pushed an asyncPreempt call.
+	// The exception is not from asyncPreempt, so not to push a
+	// sigpanic call to make it look like that. Instead, just
+	// overwrite the PC. (See issue #35773)
+	if r.ip() != 0 && r.ip() != abi.FuncPCABI0(asyncPreempt) {
+		sp := unsafe.Pointer(r.sp())
+		delta := uintptr(sys.StackAlign)
+		sp = add(sp, -delta)
+		r.set_sp(uintptr(sp))
+		if usesLR {
+			*((*uintptr)(sp)) = r.lr()
+			r.set_lr(r.ip())
+		} else {
+			*((*uintptr)(sp)) = r.ip()
+		}
+	}
+	r.set_ip(abi.FuncPCABI0(sigpanic0))
+	return _EXCEPTION_CONTINUE_EXECUTION
+}
+
+// It seems Windows searches ContinueHandler's list even
+// if ExceptionHandler returns EXCEPTION_CONTINUE_EXECUTION.
+// firstcontinuehandler will stop that search,
+// if exceptionhandler did the same earlier.
+//
+// It is nosplit for the same reason as exceptionhandler.
+//
+//go:nosplit
+func firstcontinuehandler(info *exceptionrecord, r *context, gp *g) int32 {
+	if !isgoexception(info, r) {
+		return _EXCEPTION_CONTINUE_SEARCH
+	}
+	return _EXCEPTION_CONTINUE_EXECUTION
+}
+
+var testingWER bool
+
+// lastcontinuehandler is reached, because runtime cannot handle
+// current exception. lastcontinuehandler will print crash info and exit.
+//
+// It is nosplit for the same reason as exceptionhandler.
+//
+//go:nosplit
+func lastcontinuehandler(info *exceptionrecord, r *context, gp *g) int32 {
+	if islibrary || isarchive {
+		// Go DLL/archive has been loaded in a non-go program.
+		// If the exception does not originate from go, the go runtime
+		// should not take responsibility of crashing the process.
+		return _EXCEPTION_CONTINUE_SEARCH
+	}
+	if testingWER {
+		return _EXCEPTION_CONTINUE_SEARCH
+	}
+
+	// VEH is called before SEH, but arm64 MSVC DLLs use SEH to trap
+	// illegal instructions during runtime initialization to determine
+	// CPU features, so if we make it to the last handler and we're
+	// arm64 and it's an illegal instruction and this is coming from
+	// non-Go code, then assume it's this runtime probing happen, and
+	// pass that onward to SEH.
+	if GOARCH == "arm64" && info.exceptioncode == _EXCEPTION_ILLEGAL_INSTRUCTION &&
+		(r.ip() < firstmoduledata.text || firstmoduledata.etext < r.ip()) {
+		return _EXCEPTION_CONTINUE_SEARCH
+	}
+
+	winthrow(info, r, gp)
+	return 0 // not reached
+}
+
+//go:nosplit
+func winthrow(info *exceptionrecord, r *context, gp *g) {
+	_g_ := getg()
+
+	if panicking != 0 { // traceback already printed
+		exit(2)
+	}
+	panicking = 1
+
+	// In case we're handling a g0 stack overflow, blow away the
+	// g0 stack bounds so we have room to print the traceback. If
+	// this somehow overflows the stack, the OS will trap it.
+	_g_.stack.lo = 0
+	_g_.stackguard0 = _g_.stack.lo + _StackGuard
+	_g_.stackguard1 = _g_.stackguard0
+
+	print("Exception ", hex(info.exceptioncode), " ", hex(info.exceptioninformation[0]), " ", hex(info.exceptioninformation[1]), " ", hex(r.ip()), "\n")
+
+	print("PC=", hex(r.ip()), "\n")
+	if _g_.m.incgo && gp == _g_.m.g0 && _g_.m.curg != nil {
+		if iscgo {
+			print("signal arrived during external code execution\n")
+		}
+		gp = _g_.m.curg
+	}
+	print("\n")
+
+	_g_.m.throwing = throwTypeRuntime
+	_g_.m.caughtsig.set(gp)
+
+	level, _, docrash := gotraceback()
+	if level > 0 {
+		tracebacktrap(r.ip(), r.sp(), r.lr(), gp)
+		tracebackothers(gp)
+		dumpregs(r)
+	}
+
+	if docrash {
+		crash()
+	}
+
+	exit(2)
+}
+
+func sigpanic() {
+	g := getg()
+	if !canpanic(g) {
+		throw("unexpected signal during runtime execution")
+	}
+
+	switch g.sig {
+	case _EXCEPTION_ACCESS_VIOLATION:
+		if g.sigcode1 < 0x1000 {
+			panicmem()
+		}
+		if g.paniconfault {
+			panicmemAddr(g.sigcode1)
+		}
+		print("unexpected fault address ", hex(g.sigcode1), "\n")
+		throw("fault")
+	case _EXCEPTION_INT_DIVIDE_BY_ZERO:
+		panicdivide()
+	case _EXCEPTION_INT_OVERFLOW:
+		panicoverflow()
+	case _EXCEPTION_FLT_DENORMAL_OPERAND,
+		_EXCEPTION_FLT_DIVIDE_BY_ZERO,
+		_EXCEPTION_FLT_INEXACT_RESULT,
+		_EXCEPTION_FLT_OVERFLOW,
+		_EXCEPTION_FLT_UNDERFLOW:
+		panicfloat()
+	}
+	throw("fault")
+}
+
+var (
+	badsignalmsg [100]byte
+	badsignallen int32
+)
+
+func setBadSignalMsg() {
+	const msg = "runtime: signal received on thread not created by Go.\n"
+	for i, c := range msg {
+		badsignalmsg[i] = byte(c)
+		badsignallen++
+	}
+}
+
+// Following are not implemented.
+
+func initsig(preinit bool) {
+}
+
+func sigenable(sig uint32) {
+}
+
+func sigdisable(sig uint32) {
+}
+
+func sigignore(sig uint32) {
+}
+
+func badsignal2()
+
+func raisebadsignal(sig uint32) {
+	badsignal2()
+}
+
+func signame(sig uint32) string {
+	return ""
+}
+
+//go:nosplit
+func crash() {
+	// TODO: This routine should do whatever is needed
+	// to make the Windows program abort/crash as it
+	// would if Go was not intercepting signals.
+	// On Unix the routine would remove the custom signal
+	// handler and then raise a signal (like SIGABRT).
+	// Something like that should happen here.
+	// It's okay to leave this empty for now: if crash returns
+	// the ordinary exit-after-panic happens.
+}
+
+// gsignalStack is unused on Windows.
+type gsignalStack struct{}