feat: migrate to system cache with changing core logic

internal/shutils/handlers/fakeroot.go

@@ -25,11 +25,11 @@ import (
 	"os"
 	"os/exec"
 	"runtime"
+	"slices"
 	"strings"
 	"syscall"
 	"time"
 
-	"gitea.plemya-x.ru/Plemya-x/fakeroot"
 	"mvdan.cc/sh/v3/expand"
 	"mvdan.cc/sh/v3/interp"
 )
@@ -54,7 +54,7 @@ func FakerootExecHandler(killTimeout time.Duration) interp.ExecHandlerFunc {
 			Stderr: hc.Stderr,
 		}
 
-		err = fakeroot.Apply(cmd)
+		err = Apply(cmd)
 		if err != nil {
 			return err
 		}
@@ -108,6 +108,52 @@ func FakerootExecHandler(killTimeout time.Duration) interp.ExecHandlerFunc {
 	}
 }
 
+func rootMap(m syscall.SysProcIDMap) bool {
+	return m.ContainerID == 0
+}
+
+func Apply(cmd *exec.Cmd) error {
+	uid := os.Getuid()
+	gid := os.Getgid()
+
+	// If the user is already root, there's no need for fakeroot
+	if uid == 0 {
+		return nil
+	}
+
+	// Ensure SysProcAttr isn't nil
+	if cmd.SysProcAttr == nil {
+		cmd.SysProcAttr = &syscall.SysProcAttr{}
+	}
+
+	// Create a new user namespace
+	cmd.SysProcAttr.Cloneflags |= syscall.CLONE_NEWUSER
+
+	// If the command already contains a mapping for the root user, return an error
+	if slices.ContainsFunc(cmd.SysProcAttr.UidMappings, rootMap) {
+		return nil
+	}
+
+	// If the command already contains a mapping for the root group, return an error
+	if slices.ContainsFunc(cmd.SysProcAttr.GidMappings, rootMap) {
+		return nil
+	}
+
+	cmd.SysProcAttr.UidMappings = append(cmd.SysProcAttr.UidMappings, syscall.SysProcIDMap{
+		ContainerID: 0,
+		HostID:      uid,
+		Size:        1,
+	})
+
+	cmd.SysProcAttr.GidMappings = append(cmd.SysProcAttr.GidMappings, syscall.SysProcIDMap{
+		ContainerID: 0,
+		HostID:      gid,
+		Size:        1,
+	})
+
+	return nil
+}
+
 // execEnv was extracted from github.com/mvdan/sh/interp/vars.go
 func execEnv(env expand.Environ) []string {
 	list := make([]string, 0, 64)