mirror of https://github.com/cheat/cheat.git
128 lines
2.6 KiB
Go
128 lines
2.6 KiB
Go
//go:build !js
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// +build !js
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// Package osfs provides a billy filesystem for the OS.
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package osfs
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import (
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"fmt"
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"io/fs"
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"os"
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"sync"
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"github.com/go-git/go-billy/v5"
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)
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const (
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defaultDirectoryMode = 0o755
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defaultCreateMode = 0o666
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)
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// Default Filesystem representing the root of the os filesystem.
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var Default = &ChrootOS{}
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// New returns a new OS filesystem.
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// By default paths are deduplicated, but still enforced
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// under baseDir. For more info refer to WithDeduplicatePath.
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func New(baseDir string, opts ...Option) billy.Filesystem {
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o := &options{
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deduplicatePath: true,
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}
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for _, opt := range opts {
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opt(o)
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}
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if o.Type == BoundOSFS {
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return newBoundOS(baseDir, o.deduplicatePath)
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}
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return newChrootOS(baseDir)
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}
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// WithBoundOS returns the option of using a Bound filesystem OS.
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func WithBoundOS() Option {
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return func(o *options) {
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o.Type = BoundOSFS
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}
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}
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// WithChrootOS returns the option of using a Chroot filesystem OS.
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func WithChrootOS() Option {
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return func(o *options) {
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o.Type = ChrootOSFS
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}
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}
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// WithDeduplicatePath toggles the deduplication of the base dir in the path.
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// This occurs when absolute links are being used.
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// Assuming base dir /base/dir and an absolute symlink /base/dir/target:
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//
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// With DeduplicatePath (default): /base/dir/target
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// Without DeduplicatePath: /base/dir/base/dir/target
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//
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// This option is only used by the BoundOS OS type.
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func WithDeduplicatePath(enabled bool) Option {
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return func(o *options) {
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o.deduplicatePath = enabled
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}
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}
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type options struct {
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Type
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deduplicatePath bool
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}
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type Type int
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const (
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ChrootOSFS Type = iota
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BoundOSFS
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)
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func readDir(dir string) ([]os.FileInfo, error) {
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entries, err := os.ReadDir(dir)
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if err != nil {
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return nil, err
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}
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infos := make([]fs.FileInfo, 0, len(entries))
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for _, entry := range entries {
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fi, err := entry.Info()
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if err != nil {
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return nil, err
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}
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infos = append(infos, fi)
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}
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return infos, nil
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}
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func tempFile(dir, prefix string) (billy.File, error) {
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f, err := os.CreateTemp(dir, prefix)
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if err != nil {
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return nil, err
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}
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return &file{File: f}, nil
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}
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func openFile(fn string, flag int, perm os.FileMode, createDir func(string) error) (billy.File, error) {
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if flag&os.O_CREATE != 0 {
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if createDir == nil {
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return nil, fmt.Errorf("createDir func cannot be nil if file needs to be opened in create mode")
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}
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if err := createDir(fn); err != nil {
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return nil, err
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}
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}
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f, err := os.OpenFile(fn, flag, perm)
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if err != nil {
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return nil, err
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}
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return &file{File: f}, err
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}
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// file is a wrapper for an os.File which adds support for file locking.
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type file struct {
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*os.File
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m sync.Mutex
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}
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