diff options
Diffstat (limited to 'src/runtime/signal_windows.go')
-rw-r--r-- | src/runtime/signal_windows.go | 310 |
1 files changed, 310 insertions, 0 deletions
diff --git a/src/runtime/signal_windows.go b/src/runtime/signal_windows.go new file mode 100644 index 0000000..3af2e39 --- /dev/null +++ b/src/runtime/signal_windows.go @@ -0,0 +1,310 @@ +// 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 ( + "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, funcPC(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, funcPC(lastcontinuetramp)) + } else { + stdcall2(_AddVectoredContinueHandler, 1, funcPC(firstcontinuetramp)) + stdcall2(_AddVectoredContinueHandler, 0, funcPC(lastcontinuetramp)) + } +} + +// isAbort returns true, if context r describes exception raised +// by calling runtime.abort function. +// +//go:nosplit +func isAbort(r *context) bool { + // In the case of an abort, the exception IP is one byte after + // the INT3 (this differs from UNIX OSes). + return isAbortPC(r.ip() - 1) +} + +// isgoexception reports whether this exception should be translated +// into a Go panic. +// +// 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 + } + + if isAbort(r) { + // Never turn abort into a panic. + 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: + } + 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 + } + + // After this point, it is safe to grow the stack. + + if gp.throwsplit { + // We can't safely sigpanic because it may grow the + // stack. Let it fall through. + return _EXCEPTION_CONTINUE_SEARCH + } + + // 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 = uintptr(info.exceptioninformation[0]) + gp.sigcode1 = uintptr(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() != funcPC(asyncPreempt) { + sp := unsafe.Pointer(r.sp()) + sp = add(sp, ^(unsafe.Sizeof(uintptr(0)) - 1)) // sp-- + r.set_sp(uintptr(sp)) + switch GOARCH { + default: + panic("unsupported architecture") + case "386", "amd64": + *((*uintptr)(sp)) = r.ip() + case "arm": + *((*uintptr)(sp)) = r.lr() + r.set_lr(r.ip()) + } + } + r.set_ip(funcPC(sigpanic)) + 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 + } + + _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.lockedg != 0 && _g_.m.ncgo > 0 && gp == _g_.m.g0 { + if iscgo { + print("signal arrived during external code execution\n") + } + gp = _g_.m.lockedg.ptr() + } + print("\n") + + // TODO(jordanrh1): This may be needed for 386/AMD64 as well. + if GOARCH == "arm" { + _g_.m.throwing = 1 + _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) + return 0 // not reached +} + +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{} |