// Copyright 2018 The gVisor Authors. // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License. #ifndef _GNU_SOURCE #define _GNU_SOURCE #endif #include <errno.h> #include <fcntl.h> #include <sched.h> #include <stdio.h> #include <string.h> #include <sys/stat.h> #include <sys/types.h> #include <unistd.h> int main(int argc, char** argv) { if (argc <= 2) { fprintf(stderr, "error: must provide a namespace file.\n"); fprintf(stderr, "usage: %s <file> [arguments...]\n", argv[0]); return 1; } int fd = open(argv[1], O_RDONLY); if (fd < 0) { fprintf(stderr, "error opening %s: %s\n", argv[1], strerror(errno)); return 1; } if (setns(fd, 0) < 0) { fprintf(stderr, "error joining %s: %s\n", argv[1], strerror(errno)); return 1; } execvp(argv[2], &argv[2]); return 1; }