go-sandbox/pkg/forkexec/fork_util.go
2019-09-18 01:42:10 -07:00

64 lines
1.3 KiB
Go

package forkexec
import (
"syscall"
)
// prepareExec prepares execve parameters
func prepareExec(Args, Env []string) (*byte, []*byte, []*byte, error) {
// make exec args0
argv0, err := syscall.BytePtrFromString(Args[0])
if err != nil {
return nil, nil, nil, err
}
// make exec args
argv, err := syscall.SlicePtrFromStrings(Args)
if err != nil {
return nil, nil, nil, err
}
// make env
envv, err := syscall.SlicePtrFromStrings(Env)
if err != nil {
return nil, nil, nil, err
}
return argv0, argv, envv, nil
}
// prepareFds prapares fd array
func prepareFds(files []uintptr) ([]int, int) {
fd := make([]int, len(files))
nextfd := len(files)
for i, ufd := range files {
if nextfd < int(ufd) {
nextfd = int(ufd)
}
fd[i] = int(ufd)
}
nextfd++
return fd, nextfd
}
// syscallStringFromString prepares *byte if string is not empty, other wise nil
func syscallStringFromString(str string) (*byte, error) {
if str != "" {
return syscall.BytePtrFromString(str)
}
return nil, nil
}
// preparePivotRoot prepares pivot root parameters
func preparePivotRoot(r string) (*byte, *byte, error) {
if r == "" {
return nil, nil, nil
}
root, err := syscall.BytePtrFromString(r)
if err != nil {
return nil, nil, err
}
oldRoot, err := syscall.BytePtrFromString(OldRoot)
if err != nil {
return nil, nil, err
}
return root, oldRoot, nil
}