status-go/vendor/github.com/anacrolix/missinggo/v2/pproffd/pproffd.go

123 lines
1.7 KiB
Go

// Package pproffd is for detecting resource leaks due to unclosed handles.
package pproffd
import (
"io"
"net"
"os"
"runtime/pprof"
)
var enabled = func() bool {
_, ok := os.LookupEnv("PPROFFD")
return ok
}()
var p *pprof.Profile
func init() {
if enabled {
p = pprof.NewProfile("fds")
}
}
type fd int
func (me *fd) Closed() {
if enabled {
p.Remove(me)
}
}
func add(skip int) (ret *fd) {
if enabled {
ret = new(fd)
p.Add(ret, skip+2)
}
return
}
type Wrapped interface {
Wrapped() io.Closer
}
type CloseWrapper struct {
fd *fd
c io.Closer
}
func (me CloseWrapper) Wrapped() io.Closer {
return me.c
}
func (me CloseWrapper) Close() error {
me.fd.Closed()
return me.c.Close()
}
func NewCloseWrapper(c io.Closer) CloseWrapper {
// TODO: Check enabled?
return CloseWrapper{
fd: add(2),
c: c,
}
}
type wrappedNetConn struct {
net.Conn
CloseWrapper
}
func (me wrappedNetConn) Close() error {
return me.CloseWrapper.Close()
}
// Tracks a net.Conn until Close() is explicitly called.
func WrapNetConn(nc net.Conn) net.Conn {
if !enabled {
return nc
}
if nc == nil {
return nil
}
return wrappedNetConn{
nc,
NewCloseWrapper(nc),
}
}
type OSFile interface {
io.Reader
io.Seeker
io.Closer
io.Writer
Stat() (os.FileInfo, error)
io.ReaderAt
io.WriterAt
Wrapped
}
type wrappedOSFile struct {
*os.File
CloseWrapper
}
func (me wrappedOSFile) Close() error {
return me.CloseWrapper.Close()
}
type unwrappedOsFile struct {
*os.File
}
func (me unwrappedOsFile) Wrapped() io.Closer {
return me.File
}
func WrapOSFile(f *os.File) OSFile {
if !enabled {
return unwrappedOsFile{f}
}
return &wrappedOSFile{f, NewCloseWrapper(f)}
}