Merge commit 'a213e8bcd1d8e4e5c764978879d875d2d55dd400' as 'v2'

v2/internal/assetdb/filesystem.go

@@ -0,0 +1,176 @@
+// +build !desktop
+package assetdb
+
+import (
+	"errors"
+	"io"
+	"net/http"
+	"os"
+	"path"
+	"sort"
+	"strings"
+	"time"
+)
+
+var errWhence = errors.New("Seek: invalid whence")
+var errOffset = errors.New("Seek: invalid offset")
+
+// Open implements the http.FileSystem interface for the AssetDB
+func (a *AssetDB) Open(name string) (http.File, error) {
+	if name == "/" || name == "" {
+		return &Entry{name: "/", dir: true, db: a}, nil
+	}
+
+	if data, ok := a.db[name]; ok {
+		return &Entry{name: name, data: data, size: len(data)}, nil
+	} else {
+		for n, _ := range a.db {
+			if strings.HasPrefix(n, name+"/") {
+				return &Entry{name: name, db: a, dir: true}, nil
+			}
+		}
+	}
+	return &Entry{}, os.ErrNotExist
+}
+
+// readdir returns the directory entries for the requested directory
+func (a *AssetDB) readdir(name string) ([]os.FileInfo, error) {
+	dir := name
+	var ents []string
+
+	fim := make(map[string]os.FileInfo)
+	for fn, data := range a.db {
+		if strings.HasPrefix(fn, dir) {
+			pieces := strings.Split(fn[len(dir)+1:], "/")
+			if len(pieces) == 1 {
+				fim[pieces[0]] = FI{name: pieces[0], dir: false, size: len(data)}
+				ents = append(ents, pieces[0])
+			} else {
+				fim[pieces[0]] = FI{name: pieces[0], dir: true, size: -1}
+				ents = append(ents, pieces[0])
+			}
+		}
+	}
+
+	if len(ents) == 0 {
+		return nil, os.ErrNotExist
+	}
+
+	sort.Strings(ents)
+	var list []os.FileInfo
+	for _, dir := range ents {
+		list = append(list, fim[dir])
+	}
+	return list, nil
+}
+
+// Entry implements the http.File interface to allow for
+// use in the http.FileSystem implementation of AssetDB
+type Entry struct {
+	name string
+	data []byte
+	dir  bool
+	size int
+	db   *AssetDB
+	off  int
+}
+
+// Close is a noop
+func (e Entry) Close() error {
+	return nil
+}
+
+// Read fills the slice provided returning how many bytes were written
+// and any errors encountered
+func (e *Entry) Read(p []byte) (n int, err error) {
+	if e.off >= e.size {
+		return 0, io.EOF
+	}
+	numout := len(p)
+	if numout > e.size {
+		numout = e.size
+	}
+	for i := 0; i < numout; i++ {
+		p[i] = e.data[e.off+i]
+	}
+	e.off += numout
+	n = int(numout)
+	err = nil
+	return
+}
+
+// Seek seeks to the specified offset from the location specified by whence
+func (e *Entry) Seek(offset int64, whence int) (int64, error) {
+	switch whence {
+	default:
+		return 0, errWhence
+	case io.SeekStart:
+		offset += 0
+	case io.SeekCurrent:
+		offset += int64(e.off)
+	case io.SeekEnd:
+		offset += int64(e.size)
+	}
+
+	if offset < 0 {
+		return 0, errOffset
+	}
+	e.off = int(offset)
+	return offset, nil
+}
+
+// Readdir returns the directory entries inside this entry if it is a directory
+func (e Entry) Readdir(count int) ([]os.FileInfo, error) {
+	ents := []os.FileInfo{}
+	if !e.dir {
+		return ents, errors.New("Not a directory")
+	}
+	return e.db.readdir(e.name)
+}
+
+// Stat returns information about this directory entry
+func (e Entry) Stat() (os.FileInfo, error) {
+	return FI{e.name, e.size, e.dir}, nil
+}
+
+// FI is the AssetDB implementation of os.FileInfo.
+type FI struct {
+	name string
+	size int
+	dir  bool
+}
+
+// IsDir returns true if this is a directory
+func (fi FI) IsDir() bool {
+	return fi.dir
+}
+
+// ModTime always returns now
+func (fi FI) ModTime() time.Time {
+	return time.Time{}
+}
+
+// Mode returns the file as readonly and directories
+// as world writeable and executable
+func (fi FI) Mode() os.FileMode {
+	if fi.IsDir() {
+		return 0755 | os.ModeDir
+	}
+	return 0444
+}
+
+// Name returns the name of this object without
+// any leading slashes
+func (fi FI) Name() string {
+	return path.Base(fi.name)
+}
+
+// Size returns the size of this item
+func (fi FI) Size() int64 {
+	return int64(fi.size)
+}
+
+// Sys returns nil
+func (fi FI) Sys() interface{} {
+	return nil
+}