tools/godoc/vfs/httpfs/httpfs.go

95 строки
2.1 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 httpfs implements http.FileSystem using a godoc vfs.FileSystem.
package httpfs // import "golang.org/x/tools/godoc/vfs/httpfs"
import (
"fmt"
"io"
"net/http"
"os"
"golang.org/x/tools/godoc/vfs"
)
func New(fs vfs.FileSystem) http.FileSystem {
return &httpFS{fs}
}
type httpFS struct {
fs vfs.FileSystem
}
func (h *httpFS) Open(name string) (http.File, error) {
fi, err := h.fs.Stat(name)
if err != nil {
return nil, err
}
if fi.IsDir() {
return &httpDir{h.fs, name, nil}, nil
}
f, err := h.fs.Open(name)
if err != nil {
return nil, err
}
return &httpFile{h.fs, f, name}, nil
}
// httpDir implements http.File for a directory in a FileSystem.
type httpDir struct {
fs vfs.FileSystem
name string
pending []os.FileInfo
}
func (h *httpDir) Close() error { return nil }
func (h *httpDir) Stat() (os.FileInfo, error) { return h.fs.Stat(h.name) }
func (h *httpDir) Read([]byte) (int, error) {
return 0, fmt.Errorf("cannot Read from directory %s", h.name)
}
func (h *httpDir) Seek(offset int64, whence int) (int64, error) {
if offset == 0 && whence == 0 {
h.pending = nil
return 0, nil
}
return 0, fmt.Errorf("unsupported Seek in directory %s", h.name)
}
func (h *httpDir) Readdir(count int) ([]os.FileInfo, error) {
if h.pending == nil {
d, err := h.fs.ReadDir(h.name)
if err != nil {
return nil, err
}
if d == nil {
d = []os.FileInfo{} // not nil
}
h.pending = d
}
if len(h.pending) == 0 && count > 0 {
return nil, io.EOF
}
if count <= 0 || count > len(h.pending) {
count = len(h.pending)
}
d := h.pending[:count]
h.pending = h.pending[count:]
return d, nil
}
// httpFile implements http.File for a file (not directory) in a FileSystem.
type httpFile struct {
fs vfs.FileSystem
vfs.ReadSeekCloser
name string
}
func (h *httpFile) Stat() (os.FileInfo, error) { return h.fs.Stat(h.name) }
func (h *httpFile) Readdir(int) ([]os.FileInfo, error) {
return nil, fmt.Errorf("cannot Readdir from file %s", h.name)
}