GoToSocial/vendor/github.com/tdewolff/parse/v2/buffer/writer.go

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package buffer
import (
"io"
)
// Writer implements an io.Writer over a byte slice.
type Writer struct {
buf []byte
err error
expand bool
}
// NewWriter returns a new Writer for a given byte slice.
func NewWriter(buf []byte) *Writer {
return &Writer{
buf: buf,
expand: true,
}
}
// NewStaticWriter returns a new Writer for a given byte slice. It does not reallocate and expand the byte-slice.
func NewStaticWriter(buf []byte) *Writer {
return &Writer{
buf: buf,
expand: false,
}
}
// Write writes bytes from the given byte slice and returns the number of bytes written and an error if occurred. When err != nil, n == 0.
func (w *Writer) Write(b []byte) (int, error) {
n := len(b)
end := len(w.buf)
if end+n > cap(w.buf) {
if !w.expand {
w.err = io.EOF
return 0, io.EOF
}
buf := make([]byte, end, 2*cap(w.buf)+n)
copy(buf, w.buf)
w.buf = buf
}
w.buf = w.buf[:end+n]
return copy(w.buf[end:], b), nil
}
// Len returns the length of the underlying byte slice.
func (w *Writer) Len() int {
return len(w.buf)
}
// Bytes returns the underlying byte slice.
func (w *Writer) Bytes() []byte {
return w.buf
}
// Reset empties and reuses the current buffer. Subsequent writes will overwrite the buffer, so any reference to the underlying slice is invalidated after this call.
func (w *Writer) Reset() {
w.buf = w.buf[:0]
}
// Close returns the last error.
func (w *Writer) Close() error {
return w.err
}