panic_windows.go

package main

import (
	"fmt"
	"os"
	"syscall"
	"time"
)

var (
	kernel32         = syscall.MustLoadDLL("kernel32.dll")
	procSetStdHandle = kernel32.MustFindProc("SetStdHandle")
)

var panicFile *os.File

func init() {
	var err error
	panicFile, err = os.OpenFile("panic.txt", os.O_APPEND|os.O_CREATE|os.O_RDWR|os.O_SYNC, 0666)
	if err != nil {
		l.Warnln("Panic logging:", err)
		return
	}

	err = SetStdHandle(syscall.STD_ERROR_HANDLE, syscall.Handle(panicFile.Fd()))
	if err != nil {
		l.Warnln("Panic logging:", err)
		return
	}

	fmt.Fprintf(panicFile, "%s %d\n", time.Now(), Version)
}

func SetStdHandle(stdhandle int32, handle syscall.Handle) error {
	r0, _, e1 := syscall.Syscall(procSetStdHandle.Addr(), 2, uintptr(stdhandle), uintptr(handle), 0)
	if r0 == 0 {
		if e1 != 0 {
			return error(e1)
		}
		return syscall.EINVAL
	}
	return nil
}