Compresor/Descompresor L4

l4.go

package main

import (
	"bufio"
	"io"
	"os"

	"github.com/pierrec/lz4"
)

// Compress a file, then decompress it again!
func main() {
	compress("./archivo.sql", "./sql-comprimido")
	decompress("./sql-comprimido", "./sql-descomprimido.sql")
}

func compress(inputFile, outputFile string) {
	// open input file
	fin, err := os.Open(inputFile)
	if err != nil {
		panic(err)
	}
	defer func() {
		if err := fin.Close(); err != nil {
			panic(err)
		}
	}()
	// make a read buffer
	r := bufio.NewReader(fin)

	// open output file
	fout, err := os.Create(outputFile)
	if err != nil {
		panic(err)
	}
	defer func() {
		if err := fout.Close(); err != nil {
			panic(err)
		}
	}()
	// make an lz4 write buffer
	w := lz4.NewWriter(fout)

	// make a buffer to keep chunks that are read
	buf := make([]byte, 1024)
	for {
		// read a chunk
		n, err := r.Read(buf)
		if err != nil && err != io.EOF {
			panic(err)
		}
		if n == 0 {
			break
		}

		// write a chunk
		if _, err := w.Write(buf[:n]); err != nil {
			panic(err)
		}
	}

	if err = w.Flush(); err != nil {
		panic(err)
	}
}

func decompress(inputFile, outputFile string) {
	// open input file
	fin, err := os.Open(inputFile)
	if err != nil {
		panic(err)
	}
	defer func() {
		if err := fin.Close(); err != nil {
			panic(err)
		}
	}()

	// make an lz4 read buffer
	r := lz4.NewReader(fin)

	// open output file
	fout, err := os.Create(outputFile)
	if err != nil {
		panic(err)
	}
	defer func() {
		if err := fout.Close(); err != nil {
			panic(err)
		}
	}()

	// make a write buffer
	w := bufio.NewWriter(fout)

	// make a buffer to keep chunks that are read
	buf := make([]byte, 1024)
	for {
		// read a chunk
		n, err := r.Read(buf)
		if err != nil && err != io.EOF {
			panic(err)
		}
		if n == 0 {
			break
		}

		// write a chunk
		if _, err := w.Write(buf[:n]); err != nil {
			panic(err)
		}
	}

	if err = w.Flush(); err != nil {
		panic(err)
	}
}