gotosocial/vendor/github.com/tetratelabs/wazero/internal/sysfs/readfs.go
kim 1e7b32490d
[experiment] add alternative wasm sqlite3 implementation available via build-tag (#2863)
This allows for building GoToSocial with [SQLite transpiled to WASM](https://github.com/ncruces/go-sqlite3) and accessed through [Wazero](https://wazero.io/).
2024-05-27 17:46:15 +02:00

118 lines
3.4 KiB
Go

package sysfs
import (
"io/fs"
experimentalsys "github.com/tetratelabs/wazero/experimental/sys"
)
type ReadFS struct {
experimentalsys.FS
}
// OpenFile implements the same method as documented on sys.FS
func (r *ReadFS) OpenFile(path string, flag experimentalsys.Oflag, perm fs.FileMode) (experimentalsys.File, experimentalsys.Errno) {
// Mask the mutually exclusive bits as they determine write mode.
switch flag & (experimentalsys.O_RDONLY | experimentalsys.O_WRONLY | experimentalsys.O_RDWR) {
case experimentalsys.O_WRONLY, experimentalsys.O_RDWR:
// Return the correct error if a directory was opened for write.
if flag&experimentalsys.O_DIRECTORY != 0 {
return nil, experimentalsys.EISDIR
}
return nil, experimentalsys.ENOSYS
default: // sys.O_RDONLY (integer zero) so we are ok!
}
f, errno := r.FS.OpenFile(path, flag, perm)
if errno != 0 {
return nil, errno
}
return &readFile{f}, 0
}
// Mkdir implements the same method as documented on sys.FS
func (r *ReadFS) Mkdir(path string, perm fs.FileMode) experimentalsys.Errno {
return experimentalsys.EROFS
}
// Chmod implements the same method as documented on sys.FS
func (r *ReadFS) Chmod(path string, perm fs.FileMode) experimentalsys.Errno {
return experimentalsys.EROFS
}
// Rename implements the same method as documented on sys.FS
func (r *ReadFS) Rename(from, to string) experimentalsys.Errno {
return experimentalsys.EROFS
}
// Rmdir implements the same method as documented on sys.FS
func (r *ReadFS) Rmdir(path string) experimentalsys.Errno {
return experimentalsys.EROFS
}
// Link implements the same method as documented on sys.FS
func (r *ReadFS) Link(_, _ string) experimentalsys.Errno {
return experimentalsys.EROFS
}
// Symlink implements the same method as documented on sys.FS
func (r *ReadFS) Symlink(_, _ string) experimentalsys.Errno {
return experimentalsys.EROFS
}
// Unlink implements the same method as documented on sys.FS
func (r *ReadFS) Unlink(path string) experimentalsys.Errno {
return experimentalsys.EROFS
}
// Utimens implements the same method as documented on sys.FS
func (r *ReadFS) Utimens(path string, atim, mtim int64) experimentalsys.Errno {
return experimentalsys.EROFS
}
// compile-time check to ensure readFile implements api.File.
var _ experimentalsys.File = (*readFile)(nil)
type readFile struct {
experimentalsys.File
}
// Write implements the same method as documented on sys.File.
func (r *readFile) Write([]byte) (int, experimentalsys.Errno) {
return 0, r.writeErr()
}
// Pwrite implements the same method as documented on sys.File.
func (r *readFile) Pwrite([]byte, int64) (n int, errno experimentalsys.Errno) {
return 0, r.writeErr()
}
// Truncate implements the same method as documented on sys.File.
func (r *readFile) Truncate(int64) experimentalsys.Errno {
return r.writeErr()
}
// Sync implements the same method as documented on sys.File.
func (r *readFile) Sync() experimentalsys.Errno {
return experimentalsys.EBADF
}
// Datasync implements the same method as documented on sys.File.
func (r *readFile) Datasync() experimentalsys.Errno {
return experimentalsys.EBADF
}
// Utimens implements the same method as documented on sys.File.
func (r *readFile) Utimens(int64, int64) experimentalsys.Errno {
return experimentalsys.EBADF
}
func (r *readFile) writeErr() experimentalsys.Errno {
if isDir, errno := r.IsDir(); errno != 0 {
return errno
} else if isDir {
return experimentalsys.EISDIR
}
return experimentalsys.EBADF
}