34324031cb
Signed-off-by: Adrian Cole <adrian@tetrate.io> Signed-off-by: Edoardo Vacchi <evacchi@users.noreply.github.com> Co-authored-by: Edoardo Vacchi <evacchi@users.noreply.github.com>
122 lines
3.4 KiB
Go
122 lines
3.4 KiB
Go
package sys
|
|
|
|
import (
|
|
"io"
|
|
"os"
|
|
"syscall"
|
|
"time"
|
|
|
|
"github.com/tetratelabs/wazero/internal/fsapi"
|
|
"github.com/tetratelabs/wazero/internal/platform"
|
|
"github.com/tetratelabs/wazero/internal/sysfs"
|
|
)
|
|
|
|
// StdinFile is a fs.ModeDevice file for use implementing FdStdin.
|
|
// This is safer than reading from os.DevNull as it can never overrun
|
|
// operating system file descriptors.
|
|
type StdinFile struct {
|
|
noopStdinFile
|
|
io.Reader
|
|
}
|
|
|
|
// Read implements the same method as documented on internalapi.File
|
|
func (f *StdinFile) Read(buf []byte) (int, syscall.Errno) {
|
|
n, err := f.Reader.Read(buf)
|
|
return n, platform.UnwrapOSError(err)
|
|
}
|
|
|
|
type writerFile struct {
|
|
noopStdoutFile
|
|
|
|
w io.Writer
|
|
}
|
|
|
|
// Write implements the same method as documented on internalapi.File
|
|
func (f *writerFile) Write(buf []byte) (int, syscall.Errno) {
|
|
n, err := f.w.Write(buf)
|
|
return n, platform.UnwrapOSError(err)
|
|
}
|
|
|
|
// noopStdinFile is a fs.ModeDevice file for use implementing FdStdin. This is
|
|
// safer than reading from os.DevNull as it can never overrun operating system
|
|
// file descriptors.
|
|
type noopStdinFile struct {
|
|
noopStdioFile
|
|
}
|
|
|
|
// AccessMode implements the same method as documented on internalapi.File
|
|
func (noopStdinFile) AccessMode() int {
|
|
return syscall.O_RDONLY
|
|
}
|
|
|
|
// Read implements the same method as documented on internalapi.File
|
|
func (noopStdinFile) Read([]byte) (int, syscall.Errno) {
|
|
return 0, 0 // Always EOF
|
|
}
|
|
|
|
// PollRead implements the same method as documented on internalapi.File
|
|
func (noopStdinFile) PollRead(*time.Duration) (ready bool, errno syscall.Errno) {
|
|
return true, 0 // always ready to read nothing
|
|
}
|
|
|
|
// noopStdoutFile is a fs.ModeDevice file for use implementing FdStdout and
|
|
// FdStderr.
|
|
type noopStdoutFile struct {
|
|
noopStdioFile
|
|
}
|
|
|
|
// AccessMode implements the same method as documented on internalapi.File
|
|
func (noopStdoutFile) AccessMode() int {
|
|
return syscall.O_WRONLY
|
|
}
|
|
|
|
// Write implements the same method as documented on internalapi.File
|
|
func (noopStdoutFile) Write(buf []byte) (int, syscall.Errno) {
|
|
return len(buf), 0 // same as io.Discard
|
|
}
|
|
|
|
type noopStdioFile struct {
|
|
fsapi.UnimplementedFile
|
|
}
|
|
|
|
// Stat implements the same method as documented on internalapi.File
|
|
func (noopStdioFile) Stat() (fsapi.Stat_t, syscall.Errno) {
|
|
return fsapi.Stat_t{Mode: modeDevice, Nlink: 1}, 0
|
|
}
|
|
|
|
// IsDir implements the same method as documented on internalapi.File
|
|
func (noopStdioFile) IsDir() (bool, syscall.Errno) {
|
|
return false, 0
|
|
}
|
|
|
|
// Close implements the same method as documented on internalapi.File
|
|
func (noopStdioFile) Close() (errno syscall.Errno) { return }
|
|
|
|
func stdinFile(r io.Reader) (*FileEntry, error) {
|
|
if r == nil {
|
|
return &FileEntry{Name: "stdin", IsPreopen: true, File: &noopStdinFile{}}, nil
|
|
} else if f, ok := r.(*os.File); ok {
|
|
if f, err := sysfs.NewStdioFile(true, f); err != nil {
|
|
return nil, err
|
|
} else {
|
|
return &FileEntry{Name: "stdin", IsPreopen: true, File: f}, nil
|
|
}
|
|
} else {
|
|
return &FileEntry{Name: "stdin", IsPreopen: true, File: &StdinFile{Reader: r}}, nil
|
|
}
|
|
}
|
|
|
|
func stdioWriterFile(name string, w io.Writer) (*FileEntry, error) {
|
|
if w == nil {
|
|
return &FileEntry{Name: name, IsPreopen: true, File: &noopStdoutFile{}}, nil
|
|
} else if f, ok := w.(*os.File); ok {
|
|
if f, err := sysfs.NewStdioFile(false, f); err != nil {
|
|
return nil, err
|
|
} else {
|
|
return &FileEntry{Name: name, IsPreopen: true, File: f}, nil
|
|
}
|
|
} else {
|
|
return &FileEntry{Name: name, IsPreopen: true, File: &writerFile{w: w}}, nil
|
|
}
|
|
}
|