Refactor: Remove old method of removing rlimit for pulseaudio

Previously we had the capability to remove the rlimit on pulseaudio
by calling ourselves via pkexec to elevate privileges.
A while ago we switched to fully using capabilities.
We now remove the old legacy codepath.

main.go

@@ -9,7 +9,6 @@ import (
 	"os"
 	"path/filepath"
 	"strings"
-	"syscall"
 	"time"
 
 	"github.com/BurntSushi/xgbutil"
@@ -47,7 +46,6 @@ const appName = "NoiseTorch"
 
 func main() {
 
-	var pulsepid int
 	var setcap bool
 	var sinkName string
 	var unload bool
@@ -56,7 +54,6 @@ func main() {
 	var threshold int
 	var list bool
 
-	flag.IntVar(&pulsepid, "removerlimit", -1, "for internal use only")
 	flag.BoolVar(&setcap, "setcap", false, "for internal use only")
 	flag.StringVar(&sinkName, "s", "", "Use the specified source/sink device ID")
 	flag.BoolVar(&loadInput, "i", false, "Load supressor for input. If no source device ID is specified the default pulse audio source is used.")
@@ -74,18 +71,6 @@ func main() {
 		os.Exit(0)
 	}
 
-	//TODO:remove this after 0.10. Not required anymore after that.
-	//We don't remove it right now, since someone could have an old instance running that calls the updated binary
-	if pulsepid > 0 {
-		const MaxUint = ^uint64(0)
-		new := syscall.Rlimit{Cur: MaxUint, Max: MaxUint}
-		err := setRlimit(pulsepid, &new)
-		if err != nil {
-			os.Exit(1)
-		}
-		os.Exit(0)
-	}
-
 	date := time.Now().Format("2006_01_02_15_04_05")
 	tmpdir := os.TempDir()
 	f, err := os.OpenFile(filepath.Join(tmpdir, fmt.Sprintf("noisetorch-%s.log", date)), os.O_RDWR|os.O_CREATE|os.O_APPEND, 0644)

module.go

@@ -120,13 +120,9 @@ func loadSupressor(ctx *ntcontext, inp *device, out *device) error {
 		return err
 	}
 	log.Printf("Rlimit: %+v. Trying to remove.\n", lim)
-	if hasCapSysResource(getCurrentCaps()) {
-		log.Printf("Have capabilities\n")
-		removeRlimit(pid)
-	} else {
-		log.Printf("Capabilities missing, removing via pkexec\n")
-		removeRlimitAsRoot(pid)
-	}
+
+	removeRlimit(pid)
+
 	defer setRlimit(pid, &lim) // lowering RLIMIT doesn't require root
 
 	newLim, err := getRlimit(pid)

rlimit.go

@@ -3,8 +3,6 @@ package main
 import (
 	"io/ioutil"
 	"log"
-	"os"
-	"os/exec"
 	"strconv"
 	"strings"
 	"syscall"
@@ -52,20 +50,6 @@ func removeRlimit(pid int) {
 	}
 }
 
-func removeRlimitAsRoot(pid int) {
-	self, err := os.Executable()
-	if err != nil {
-		log.Fatalf("Couldn't find path to own binary\n")
-	}
-
-	cmd := exec.Command("pkexec", self, "-removerlimit", strconv.Itoa(pid))
-	log.Printf("Calling: %s\n", cmd.String())
-	err = cmd.Run()
-	if err != nil {
-		log.Printf("Couldn't remove rlimit as root: %v\n", err)
-	}
-}
-
 func pRlimit(pid int, limit uintptr, new *syscall.Rlimit, old *syscall.Rlimit) error {
 	_, _, errno := syscall.RawSyscall6(syscall.SYS_PRLIMIT64,
 		uintptr(pid),