skipto.go

package bufutil

import (
	"bufio"
	"bytes"
)

// SkipTo finds the first instance of delim and discards everything before it.
func SkipTo(br *bufio.Reader, delim []byte) (err error) {
	min := len(delim)
	if min == 0 {
		return nil
	}
	for {
		n := br.Buffered()
		if n < min {
			n = min
		}
		buf, err := br.Peek(n)
		if err != nil {
			return err
		}
		if i := bytes.Index(buf, delim); i >= 0 {
			_, err := br.Discard(i)
			return err
		}
		if _, err = br.Discard(n - min + 1); err != nil {
			return err
		}
	}
}