site/vendor/layeh.com/asar/builder.go

81 lines
1.6 KiB
Go

package asar // import "layeh.com/asar"
import (
"io"
"strings"
)
// Builder helps construct an Entry.
//
// A builder keeps track of the root Entry and the active Entry. When entries
// are added using the Add* methods, they are added as children to the active
// Entry.
type Builder struct {
root, current *Entry
}
// Root returns the root Entry.
func (b *Builder) Root() *Entry {
return b.root
}
func (b *Builder) init() {
if b.root == nil {
b.root = &Entry{
Flags: FlagDir,
}
b.current = b.root
}
}
// Parent sets the active entry to the parent of the active Entry (i.e. moves up
// a level).
//
// The function panics if called on the root Entry.
func (b *Builder) Parent() *Builder {
if b.current == b.root {
panic("root has no parent")
}
b.current = b.current.Parent
return b
}
// AddString adds a new file Entry whose contents are the given string.
func (b *Builder) AddString(name, contents string, flags Flag) *Builder {
return b.Add(name, strings.NewReader(contents), int64(len(contents)), flags)
}
// Add adds a new file Entry.
func (b *Builder) Add(name string, ra io.ReaderAt, size int64, flags Flag) *Builder {
b.init()
child := &Entry{
Name: name,
Size: size,
Flags: flags,
Parent: b.current,
r: ra,
}
b.current.Children = append(b.current.Children, child)
return b
}
// AddDir adds a new directory Entry. The active Entry is switched to this newly
// added Entry.
func (b *Builder) AddDir(name string, flags Flag) *Builder {
b.init()
child := &Entry{
Name: name,
Flags: flags | FlagDir,
Parent: b.current,
}
b.current.Children = append(b.current.Children, child)
b.current = child
return b
}