gistfile1.go

package bench

import (
	"bufio"
	"bytes"
	"errors"
	"fmt"
	"io"
	"os"
)

func Find(path, s string) (string, error) {
	if s == "" {
		return "", errors.New("")
	}
	var err error
	var file *os.File
	file, err = os.Open(path)
	if err != nil {
		return "", err
	}
	var (
		r          *bufio.Reader = bufio.NewReader(file)
		line       string
		position   int
		i          int
		res        bytes.Buffer
		ln         int
		first      bool = true
		lineLength int
		sLength    int = len(s)
	)
	for {
		line, err = r.ReadString('\n')
		if err == io.EOF {
			break
		}
		ln++
		lineLength = len(line)
	Loop:
		for position = 0; position < lineLength; position++ {
			for i = 0; i < sLength; i++ {
				if s[i] != line[position+i] {
					continue Loop
				}
			}
			if first {
				first = false
				res.WriteString(fmt.Sprintf("%v:%v", ln, position))
			} else {
				res.WriteString(fmt.Sprintf(",%v:%v", ln, position))
			}
		}
	}
	return res.String(), nil
}