proc/native: implement Copy/RestoreRegisters on windows

pkg/proc/native/proc_windows.go

@@ -57,6 +57,7 @@ func Launch(cmd []string, wd string, foreground bool) (*Process, error) {
 
 	var p *os.Process
 	dbp := New(0)
+	dbp.common = proc.NewCommonProcess(true)
 	dbp.execPtraceFunc(func() {
 		attr := &os.ProcAttr{
 			Dir:   wd,

pkg/proc/native/registers_linux_amd64.go

@@ -325,5 +325,16 @@ func (thread *Thread) fpRegisters() (regs []proc.Register, fpregs proc.LinuxX86X
 }
 
 func (r *Regs) Copy() proc.Registers {
-	return r
+	var rr Regs
+	rr.regs = &sys.PtraceRegs{}
+	rr.fpregset = &proc.LinuxX86Xstate{}
+	*(rr.regs) = *(r.regs)
+	if r.fpregset != nil {
+		*(rr.fpregset) = *(r.fpregset)
+	}
+	if r.fpregs != nil {
+		rr.fpregs = make([]proc.Register, len(r.fpregs))
+		copy(rr.fpregs, r.fpregs)
+	}
+	return &rr
 }

pkg/proc/native/registers_windows_amd64.go

@@ -33,6 +33,7 @@ type Regs struct {
 	fs      uint64
 	gs      uint64
 	tls     uint64
+	context *_CONTEXT
 	fltSave *_XMM_SAVE_AREA32
 }
 
@@ -374,11 +375,16 @@ func registers(thread *Thread, floatingPoint bool) (proc.Registers, error) {
 	if floatingPoint {
 		regs.fltSave = &context.FltSave
 	}
+	regs.context = context
 
 	return regs, nil
 }
 
 func (r *Regs) Copy() proc.Registers {
-	//TODO(aarzilli): implement this to support function calls
-	return nil
+	var rr Regs
+	rr = *r
+	rr.context = newCONTEXT()
+	*(rr.context) = *(r.context)
+	rr.fltSave = &rr.context.FltSave
+	return &rr
 }

pkg/proc/native/threads_windows.go

@@ -125,6 +125,9 @@ func (t *Thread) WriteMemory(addr uintptr, data []byte) (int, error) {
 	if t.dbp.exited {
 		return 0, proc.ProcessExitedError{Pid: t.dbp.pid}
 	}
+	if len(data) == 0 {
+		return 0, nil
+	}
 	var count uintptr
 	err := _WriteProcessMemory(t.dbp.os.hProcess, addr, &data[0], uintptr(len(data)), &count)
 	if err != nil {
@@ -151,5 +154,5 @@ func (t *Thread) ReadMemory(buf []byte, addr uintptr) (int, error) {
 }
 
 func (t *Thread) restoreRegisters(savedRegs proc.Registers) error {
-	return errors.New("not implemented")
+	return _SetThreadContext(t.os.hThread, savedRegs.(*Regs).context)
 }

pkg/proc/registers.go

@@ -24,7 +24,7 @@ type Registers interface {
 	GAddr() (uint64, bool)
 	Get(int) (uint64, error)
 	Slice() []Register
-	// Copy returns a copy of this registers that is guaranteed not to change
+	// Copy returns a copy of the registers that is guaranteed not to change
 	// when the registers of the associated thread change.
 	Copy() Registers
 }

pkg/proc/test/support.go

@@ -251,18 +251,7 @@ func MustSupportFunctionCalls(t *testing.T, testBackend string) {
 		t.Skip("this version of Go does not support function calls")
 	}
 
-	const unsupported = "this backend does not support function calls"
-
-	if testBackend == "rr" {
-		t.Skip(unsupported)
-	}
-
-	switch runtime.GOOS {
-	case "darwin":
-		if testBackend == "native" {
-			t.Skip(unsupported)
-		}
-	case "windows":
-		t.Skip(unsupported)
+	if testBackend == "rr" || (runtime.GOOS == "darwin" && testBackend == "native") {
+		t.Skip("this backend does not support function calls")
 	}
 }