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// Copyright 2015 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 main
import (
"fmt"
"runtime"
"runtime/debug"
"time"
)
func init() {
registerInit("InitDeadlock", InitDeadlock)
registerInit("NoHelperGoroutines", NoHelperGoroutines)
register("SimpleDeadlock", SimpleDeadlock)
register("LockedDeadlock", LockedDeadlock)
register("LockedDeadlock2", LockedDeadlock2)
register("GoexitDeadlock", GoexitDeadlock)
register("StackOverflow", StackOverflow)
register("ThreadExhaustion", ThreadExhaustion)
register("RecursivePanic", RecursivePanic)
register("RecursivePanic2", RecursivePanic2)
register("RecursivePanic3", RecursivePanic3)
register("RecursivePanic4", RecursivePanic4)
register("RecursivePanic5", RecursivePanic5)
register("GoexitExit", GoexitExit)
register("GoNil", GoNil)
register("MainGoroutineID", MainGoroutineID)
register("Breakpoint", Breakpoint)
register("GoexitInPanic", GoexitInPanic)
register("PanicAfterGoexit", PanicAfterGoexit)
register("RecoveredPanicAfterGoexit", RecoveredPanicAfterGoexit)
register("RecoverBeforePanicAfterGoexit", RecoverBeforePanicAfterGoexit)
register("RecoverBeforePanicAfterGoexit2", RecoverBeforePanicAfterGoexit2)
register("PanicTraceback", PanicTraceback)
register("GoschedInPanic", GoschedInPanic)
register("SyscallInPanic", SyscallInPanic)
register("PanicLoop", PanicLoop)
}
func SimpleDeadlock() {
select {}
panic("not reached")
}
func InitDeadlock() {
select {}
panic("not reached")
}
func LockedDeadlock() {
runtime.LockOSThread()
select {}
}
func LockedDeadlock2() {
go func() {
runtime.LockOSThread()
select {}
}()
time.Sleep(time.Millisecond)
select {}
}
func GoexitDeadlock() {
F := func() {
for i := 0; i < 10; i++ {
}
}
go F()
go F()
runtime.Goexit()
}
func StackOverflow() {
var f func() byte
f = func() byte {
var buf [64 << 10]byte
return buf[0] + f()
}
debug.SetMaxStack(1474560)
f()
}
func ThreadExhaustion() {
debug.SetMaxThreads(10)
c := make(chan int)
for i := 0; i < 100; i++ {
go func() {
runtime.LockOSThread()
c <- 0
select {}
}()
<-c
}
}
func RecursivePanic() {
func() {
defer func() {
fmt.Println(recover())
}()
var x [8192]byte
func(x [8192]byte) {
defer func() {
if err := recover(); err != nil {
panic("wrap: " + err.(string))
}
}()
panic("bad")
}(x)
}()
panic("again")
}
// Same as RecursivePanic, but do the first recover and the second panic in
// separate defers, and make sure they are executed in the correct order.
func RecursivePanic2() {
func() {
defer func() {
fmt.Println(recover())
}()
var x [8192]byte
func(x [8192]byte) {
defer func() {
panic("second panic")
}()
defer func() {
fmt.Println(recover())
}()
panic("first panic")
}(x)
}()
panic("third panic")
}
// Make sure that the first panic finished as a panic, even though the second
// panic was recovered
func RecursivePanic3() {
defer func() {
defer func() {
recover()
}()
panic("second panic")
}()
panic("first panic")
}
// Test case where a single defer recovers one panic but starts another panic. If
// the second panic is never recovered, then the recovered first panic will still
// appear on the panic stack (labeled '[recovered]') and the runtime stack.
func RecursivePanic4() {
defer func() {
recover()
panic("second panic")
}()
panic("first panic")
}
// Test case where we have an open-coded defer higher up the stack (in two), and
// in the current function (three) we recover in a defer while we still have
// another defer to be processed.
func RecursivePanic5() {
one()
panic("third panic")
}
//go:noinline
func one() {
two()
}
//go:noinline
func two() {
defer func() {
}()
three()
}
//go:noinline
func three() {
defer func() {
}()
defer func() {
fmt.Println(recover())
}()
defer func() {
fmt.Println(recover())
panic("second panic")
}()
panic("first panic")
}
func GoexitExit() {
println("t1")
go func() {
time.Sleep(time.Millisecond)
}()
i := 0
println("t2")
runtime.SetFinalizer(&i, func(p *int) {})
println("t3")
runtime.GC()
println("t4")
runtime.Goexit()
}
func GoNil() {
defer func() {
recover()
}()
var f func()
go f()
select {}
}
func MainGoroutineID() {
panic("test")
}
func NoHelperGoroutines() {
i := 0
runtime.SetFinalizer(&i, func(p *int) {})
time.AfterFunc(time.Hour, func() {})
panic("oops")
}
func Breakpoint() {
runtime.Breakpoint()
}
func GoexitInPanic() {
go func() {
defer func() {
runtime.Goexit()
}()
panic("hello")
}()
runtime.Goexit()
}
type errorThatGosched struct{}
func (errorThatGosched) Error() string {
runtime.Gosched()
return "errorThatGosched"
}
func GoschedInPanic() {
panic(errorThatGosched{})
}
type errorThatPrint struct{}
func (errorThatPrint) Error() string {
fmt.Println("1")
fmt.Println("2")
return "3"
}
func SyscallInPanic() {
panic(errorThatPrint{})
}
func PanicAfterGoexit() {
defer func() {
panic("hello")
}()
runtime.Goexit()
}
func RecoveredPanicAfterGoexit() {
defer func() {
defer func() {
r := recover()
if r == nil {
panic("bad recover")
}
}()
panic("hello")
}()
runtime.Goexit()
}
func RecoverBeforePanicAfterGoexit() {
// 1. defer a function that recovers
// 2. defer a function that panics
// 3. call goexit
// Goexit runs the #2 defer. Its panic
// is caught by the #1 defer. For Goexit, we explicitly
// resume execution in the Goexit loop, instead of resuming
// execution in the caller (which would make the Goexit disappear!)
defer func() {
r := recover()
if r == nil {
panic("bad recover")
}
}()
defer func() {
panic("hello")
}()
runtime.Goexit()
}
func RecoverBeforePanicAfterGoexit2() {
for i := 0; i < 2; i++ {
defer func() {
}()
}
// 1. defer a function that recovers
// 2. defer a function that panics
// 3. call goexit
// Goexit runs the #2 defer. Its panic
// is caught by the #1 defer. For Goexit, we explicitly
// resume execution in the Goexit loop, instead of resuming
// execution in the caller (which would make the Goexit disappear!)
defer func() {
r := recover()
if r == nil {
panic("bad recover")
}
}()
defer func() {
panic("hello")
}()
runtime.Goexit()
}
func PanicTraceback() {
pt1()
}
func pt1() {
defer func() {
panic("panic pt1")
}()
pt2()
}
func pt2() {
defer func() {
panic("panic pt2")
}()
panic("hello")
}
type panicError struct{}
func (*panicError) Error() string {
panic("double error")
}
func PanicLoop() {
panic(&panicError{})
}
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