/
main.go
82 lines (68 loc) · 1.35 KB
/
main.go
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package main
import (
"flag"
"fmt"
"io"
"log"
"os"
"performance-and-scalability-of-go-applications/04-profiling-and-tracing/runlengthencoding/rle"
"runtime/pprof"
)
func encodeFile(f string) (n int64, err error) {
in, err := os.Open(f)
if err != nil {
return n, err
}
defer in.Close()
encoded, err := os.Create("encoded.rle")
if err != nil {
return n, err
}
defer encoded.Close()
rleWriter := rle.NewWriter(encoded)
return io.Copy(rleWriter, in)
}
func decodeFile(f string) (n int64, err error) {
in, err := os.Open(f)
if err != nil {
return n, err
}
defer in.Close()
decoded, err := os.Create("decoded.out")
if err != nil {
return n, err
}
defer decoded.Close()
rleReader := rle.NewReader(in)
return io.Copy(decoded, rleReader)
}
func main() {
cpuProfile := flag.String("cpuprofile", "", "write cpu profile to file")
flag.Parse()
if *cpuProfile != "" {
f, err := os.Create(*cpuProfile)
if err != nil {
log.Fatal(err)
}
pprof.StartCPUProfile(f)
defer pprof.StopCPUProfile()
}
if len(flag.Args()) < 2 {
fmt.Println("missing arguments")
return
}
switch flag.Args()[0] {
case "e":
_, err := encodeFile(flag.Args()[1])
if err != nil {
panic(err)
}
case "d":
_, err := decodeFile(flag.Args()[1])
if err != nil {
panic(err)
}
default:
fmt.Printf("unknown option %s\n", flag.Args()[0])
}
}