// Copyright 2010 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 "unsafe"

func dumpregs(u *ureg) {
	print("ax    ", hex(u.ax), "\n")
	print("bx    ", hex(u.bx), "\n")
	print("cx    ", hex(u.cx), "\n")
	print("dx    ", hex(u.dx), "\n")
	print("di    ", hex(u.di), "\n")
	print("si    ", hex(u.si), "\n")
	print("bp    ", hex(u.bp), "\n")
	print("sp    ", hex(u.sp), "\n")
	print("r8    ", hex(u.r8), "\n")
	print("r9    ", hex(u.r9), "\n")
	print("r10   ", hex(u.r10), "\n")
	print("r11   ", hex(u.r11), "\n")
	print("r12   ", hex(u.r12), "\n")
	print("r13   ", hex(u.r13), "\n")
	print("r14   ", hex(u.r14), "\n")
	print("r15   ", hex(u.r15), "\n")
	print("ip    ", hex(u.ip), "\n")
	print("flags ", hex(u.flags), "\n")
	print("cs    ", hex(uint64(u.cs)), "\n")
	print("fs    ", hex(uint64(u.fs)), "\n")
	print("gs    ", hex(uint64(u.gs)), "\n")
}

func sighandler(_ureg *ureg, note *byte, gp *g) int {
	_g_ := getg()
	var t sigTabT
	var docrash bool
	var length int
	var sig int
	var flags int

	// The kernel will never pass us a nil note or ureg so we probably
	// made a mistake somewhere in sigtramp.
	if _ureg == nil || note == nil {
		print("sighandler: ureg ", _ureg, " note ", note, "\n")
		goto Throw
	}
	// Check that the note is no more than ERRMAX bytes (including
	// the trailing NUL). We should never receive a longer note.
	length = findnull(note)
	if length > _ERRMAX-1 {
		print("sighandler: note is longer than ERRMAX\n")
		goto Throw
	}
	// See if the note matches one of the patterns in sigtab.
	// Notes that do not match any pattern can be handled at a higher
	// level by the program but will otherwise be ignored.
	flags = _SigNotify
	for sig, t = range sigtable {
		n := len(t.name)
		if length < n {
			continue
		}
		if strncmp(note, &t.name[0], uintptr(n)) == 0 {
			flags = t.flags
			break
		}
	}
	if flags&_SigGoExit != 0 {
		exits((*byte)(add(unsafe.Pointer(note), 9))) // Strip "go: exit " prefix.
	}
	if flags&_SigPanic != 0 {
		// Copy the error string from sigtramp's stack into m->notesig so
		// we can reliably access it from the panic routines.
		memmove(unsafe.Pointer(_g_.m.notesig), unsafe.Pointer(note), uintptr(length+1))
		gp.sig = uint32(sig)
		gp.sigpc = uintptr(_ureg.ip)
		// Only push sigpanic if PC != 0.
		//
		// If PC == 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 sigpanic instead. (Otherwise the trace will end at
		// sigpanic and we won't get to see who faulted).
		if _ureg.ip != 0 {
			sp := _ureg.sp
			if regSize > ptrSize {
				sp -= ptrSize
				*(*uintptr)(unsafe.Pointer(uintptr(sp))) = 0
			}
			sp -= ptrSize
			*(*uintptr)(unsafe.Pointer(uintptr(sp))) = uintptr(_ureg.ip)
			_ureg.sp = sp
		}
		_ureg.ip = uint64(funcPC(sigpanic))
		return _NCONT
	}
	if flags&_SigNotify != 0 {
		// TODO(ality): See if os/signal wants it.
		//if(sigsend(...))
		//	return _NCONT;
	}
	if flags&_SigKill != 0 {
		goto Exit
	}
	if flags&_SigThrow == 0 {
		return _NCONT
	}
Throw:
	_g_.m.throwing = 1
	_g_.m.caughtsig = gp
	startpanic()
	print(gostringnocopy(note), "\n")
	print("PC=", hex(_ureg.ip), "\n")
	print("\n")
	if gotraceback(&docrash) > 0 {
		goroutineheader(gp)
		tracebacktrap(uintptr(_ureg.ip), uintptr(_ureg.sp), 0, gp)
		tracebackothers(gp)
		print("\n")
		dumpregs(_ureg)
	}
	if docrash {
		crash()
	}
Exit:
	goexitsall(note)
	exits(note)
	return _NDFLT // not reached
}

func sigenable(sig uint32) {
}

func sigdisable(sig uint32) {
}

func resetcpuprofiler(hz int32) {
	// TODO: Enable profiling interrupts.
	getg().m.profilehz = hz
}