a06abd7493
When we try to pull an image with "ctr pull xxx", the progress bar display will flush all the screen and make it so hard to find useful information for user. This commit fixes bugs for the progress bar, by correcting "line counting" algorithm. Previous algorithm only counts number of "\n", but one line can be longer than screen width, in which case it should be counted as two lines. Also updated the screen cleaning ESC chars. Signed-off-by: Zhang Wei <zhangwei555@huawei.com>
74 lines
1.4 KiB
Go
74 lines
1.4 KiB
Go
package progress
|
|
|
|
import (
|
|
"bytes"
|
|
"fmt"
|
|
"io"
|
|
"strings"
|
|
|
|
"github.com/containerd/console"
|
|
)
|
|
|
|
// Writer buffers writes until flush, at which time the last screen is cleared
|
|
// and the current buffer contents are written. This is useful for
|
|
// implementing progress displays, such as those implemented in docker and
|
|
// git.
|
|
type Writer struct {
|
|
buf bytes.Buffer
|
|
w io.Writer
|
|
lines int
|
|
}
|
|
|
|
// NewWriter returns a writer
|
|
func NewWriter(w io.Writer) *Writer {
|
|
return &Writer{
|
|
w: w,
|
|
}
|
|
}
|
|
|
|
// Write the provided bytes
|
|
func (w *Writer) Write(p []byte) (n int, err error) {
|
|
return w.buf.Write(p)
|
|
}
|
|
|
|
// Flush should be called when refreshing the current display.
|
|
func (w *Writer) Flush() error {
|
|
if w.buf.Len() == 0 {
|
|
return nil
|
|
}
|
|
|
|
if err := w.clear(); err != nil {
|
|
return err
|
|
}
|
|
|
|
ws, err := console.Current().Size()
|
|
if err != nil {
|
|
return fmt.Errorf("failed to get terminal width: %v", err)
|
|
}
|
|
strlines := strings.Split(w.buf.String(), "\n")
|
|
w.lines = -1
|
|
for _, line := range strlines {
|
|
w.lines += len(line)/int(ws.Width) + 1
|
|
}
|
|
|
|
if _, err := w.w.Write(w.buf.Bytes()); err != nil {
|
|
return err
|
|
}
|
|
|
|
w.buf.Reset()
|
|
return nil
|
|
}
|
|
|
|
// TODO(stevvooe): The following are system specific. Break these out if we
|
|
// decide to build this package further.
|
|
|
|
func (w *Writer) clear() error {
|
|
for i := 0; i < w.lines; i++ {
|
|
if _, err := fmt.Fprintf(w.w, "\x1b[1A\x1b[2K\r"); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|