mirror of
https://github.com/golang/go
synced 2024-10-01 01:18:32 -06:00
24257c8cd2
Change-Id: Idda6e64580432cb9a731e4ebf4005ee4ceb4202d Reviewed-on: https://go-review.googlesource.com/1244 Reviewed-by: Andrew Gerrand <adg@golang.org>
90 lines
1.8 KiB
Go
90 lines
1.8 KiB
Go
// Copyright 2013 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 gatefs provides an implementation of the FileSystem
|
|
// interface that wraps another FileSystem and limits its concurrency.
|
|
package gatefs // import "golang.org/x/tools/godoc/vfs/gatefs"
|
|
|
|
import (
|
|
"fmt"
|
|
"os"
|
|
|
|
"golang.org/x/tools/godoc/vfs"
|
|
)
|
|
|
|
// New returns a new FileSystem that delegates to fs.
|
|
// If gateCh is non-nil and buffered, it's used as a gate
|
|
// to limit concurrency on calls to fs.
|
|
func New(fs vfs.FileSystem, gateCh chan bool) vfs.FileSystem {
|
|
if cap(gateCh) == 0 {
|
|
return fs
|
|
}
|
|
return gatefs{fs, gate(gateCh)}
|
|
}
|
|
|
|
type gate chan bool
|
|
|
|
func (g gate) enter() { g <- true }
|
|
func (g gate) leave() { <-g }
|
|
|
|
type gatefs struct {
|
|
fs vfs.FileSystem
|
|
gate
|
|
}
|
|
|
|
func (fs gatefs) String() string {
|
|
return fmt.Sprintf("gated(%s, %d)", fs.fs.String(), cap(fs.gate))
|
|
}
|
|
|
|
func (fs gatefs) Open(p string) (vfs.ReadSeekCloser, error) {
|
|
fs.enter()
|
|
defer fs.leave()
|
|
rsc, err := fs.fs.Open(p)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return gatef{rsc, fs.gate}, nil
|
|
}
|
|
|
|
func (fs gatefs) Lstat(p string) (os.FileInfo, error) {
|
|
fs.enter()
|
|
defer fs.leave()
|
|
return fs.fs.Lstat(p)
|
|
}
|
|
|
|
func (fs gatefs) Stat(p string) (os.FileInfo, error) {
|
|
fs.enter()
|
|
defer fs.leave()
|
|
return fs.fs.Stat(p)
|
|
}
|
|
|
|
func (fs gatefs) ReadDir(p string) ([]os.FileInfo, error) {
|
|
fs.enter()
|
|
defer fs.leave()
|
|
return fs.fs.ReadDir(p)
|
|
}
|
|
|
|
type gatef struct {
|
|
rsc vfs.ReadSeekCloser
|
|
gate
|
|
}
|
|
|
|
func (f gatef) Read(p []byte) (n int, err error) {
|
|
f.enter()
|
|
defer f.leave()
|
|
return f.rsc.Read(p)
|
|
}
|
|
|
|
func (f gatef) Seek(offset int64, whence int) (ret int64, err error) {
|
|
f.enter()
|
|
defer f.leave()
|
|
return f.rsc.Seek(offset, whence)
|
|
}
|
|
|
|
func (f gatef) Close() error {
|
|
f.enter()
|
|
defer f.leave()
|
|
return f.rsc.Close()
|
|
}
|