#include <sys/mount.h>
#include <sys/types.h>
#include <sys/stat.h>
+#include <sys/statfs.h>
#include <sys/param.h>
#include <fcntl.h>
#include <stdio.h>
#include <errno.h>
#include <ctype.h>
#include <dirent.h>
-#include <err.h>
+#include <getopt.h>
+
+#include "c.h"
+#include "nls.h"
+#include "closestream.h"
+#include "statfs_magic.h"
#ifndef MS_MOVE
#define MS_MOVE 8192
#endif
+#ifndef MNT_DETACH
+#define MNT_DETACH 0x00000002 /* Just detach from the tree */
+#endif
+
/* remove all files/directories below dirName -- don't cross mountpoints */
static int recursiveRemove(int fd)
{
int dfd;
if (!(dir = fdopendir(fd))) {
- warn("failed to open directory");
+ warn(_("failed to open directory"));
goto done;
}
/* fdopendir() precludes us from continuing to use the input fd */
dfd = dirfd(dir);
-
if (fstat(dfd, &rb)) {
- warn("failed to stat directory");
+ warn(_("stat failed"));
goto done;
}
while(1) {
struct dirent *d;
+ int isdir = 0;
errno = 0;
if (!(d = readdir(dir))) {
if (errno) {
- warn("failed to read directory");
+ warn(_("failed to read directory"));
goto done;
}
break; /* end of directory */
if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
continue;
-
- if (d->d_type == DT_DIR) {
+#ifdef _DIRENT_HAVE_D_TYPE
+ if (d->d_type == DT_DIR || d->d_type == DT_UNKNOWN)
+#endif
+ {
struct stat sb;
if (fstatat(dfd, d->d_name, &sb, AT_SYMLINK_NOFOLLOW)) {
- warn("failed to stat %s", d->d_name);
+ warn(_("stat of %s failed"), d->d_name);
continue;
}
- /* remove subdirectories if device is same as dir */
- if (sb.st_dev == rb.st_dev) {
+ /* skip if device is not the same */
+ if (sb.st_dev != rb.st_dev)
+ continue;
+
+ /* remove subdirectories */
+ if (S_ISDIR(sb.st_mode)) {
int cfd;
cfd = openat(dfd, d->d_name, O_RDONLY);
- if (cfd >= 0) {
- recursiveRemove(cfd);
- close(cfd);
- }
- } else
- continue;
+ if (cfd >= 0)
+ recursiveRemove(cfd); /* it closes cfd too */
+ isdir = 1;
+ }
}
- if (unlinkat(dfd, d->d_name,
- d->d_type == DT_DIR ? AT_REMOVEDIR : 0))
- warn("failed to unlink %s", d->d_name);
+ if (unlinkat(dfd, d->d_name, isdir ? AT_REMOVEDIR : 0))
+ warn(_("failed to unlink %s"), d->d_name);
}
rc = 0; /* success */
-
done:
if (dir)
closedir(dir);
+ else
+ close(fd);
return rc;
}
static int switchroot(const char *newroot)
{
/* Don't try to unmount the old "/", there's no way to do it. */
- const char *umounts[] = { "/dev", "/proc", "/sys", NULL };
+ const char *umounts[] = { "/dev", "/proc", "/sys", "/run", NULL };
int i;
- int cfd;
- pid_t pid;
+ int cfd = -1;
+ struct stat newroot_stat, oldroot_stat, sb;
+
+ if (stat("/", &oldroot_stat) != 0) {
+ warn(_("stat of %s failed"), "/");
+ return -1;
+ }
+
+ if (stat(newroot, &newroot_stat) != 0) {
+ warn(_("stat of %s failed"), newroot);
+ return -1;
+ }
for (i = 0; umounts[i] != NULL; i++) {
char newmount[PATH_MAX];
snprintf(newmount, sizeof(newmount), "%s%s", newroot, umounts[i]);
+ if ((stat(umounts[i], &sb) == 0) && sb.st_dev == oldroot_stat.st_dev) {
+ /* mount point to move seems to be a normal directory or stat failed */
+ continue;
+ }
+
+ if ((stat(newmount, &sb) != 0) || (sb.st_dev != newroot_stat.st_dev)) {
+ /* mount point seems to be mounted already or stat failed */
+ umount2(umounts[i], MNT_DETACH);
+ continue;
+ }
+
if (mount(umounts[i], newmount, NULL, MS_MOVE, NULL) < 0) {
- warn("failed to mount moving %s to %s",
+ warn(_("failed to mount moving %s to %s"),
umounts[i], newmount);
- warnx("forcing unmount of %s", umounts[i]);
+ warnx(_("forcing unmount of %s"), umounts[i]);
umount2(umounts[i], MNT_FORCE);
}
}
if (chdir(newroot)) {
- warn("failed to change directory to %s", newroot);
+ warn(_("failed to change directory to %s"), newroot);
return -1;
}
cfd = open("/", O_RDONLY);
+ if (cfd < 0) {
+ warn(_("cannot open %s"), "/");
+ goto fail;
+ }
if (mount(newroot, "/", NULL, MS_MOVE, NULL) < 0) {
- warn("failed to mount moving %s to /", newroot);
- return -1;
+ warn(_("failed to mount moving %s to /"), newroot);
+ goto fail;
}
if (chroot(".")) {
- warn("failed to change root");
- return -1;
+ warn(_("failed to change root"));
+ goto fail;
}
- if (cfd >= 0) {
- pid = fork();
- if (pid <= 0) {
+ if (chdir("/")) {
+ warn(_("cannot change directory to %s"), "/");
+ goto fail;
+ }
+
+ switch (fork()) {
+ case 0: /* child */
+ {
+ struct statfs stfs;
+
+ if (fstatfs(cfd, &stfs) == 0 &&
+ (F_TYPE_EQUAL(stfs.f_type, STATFS_RAMFS_MAGIC) ||
+ F_TYPE_EQUAL(stfs.f_type, STATFS_TMPFS_MAGIC)))
recursiveRemove(cfd);
- if (pid == 0)
- exit(EXIT_SUCCESS);
+ else {
+ warn(_("old root filesystem is not an initramfs"));
+ close(cfd);
}
+ exit(EXIT_SUCCESS);
+ }
+ case -1: /* error */
+ break;
+
+ default: /* parent */
close(cfd);
+ return 0;
}
- return 0;
-}
-static void usage(FILE *output)
-{
- fprintf(output, "usage: %s <newrootdir> <init> <args to init>\n",
- program_invocation_short_name);
- exit(output == stderr ? EXIT_FAILURE : EXIT_SUCCESS);
+fail:
+ if (cfd >= 0)
+ close(cfd);
+ return -1;
}
-static void version(void)
+static void __attribute__((__noreturn__)) usage(void)
{
- fprintf(stdout, "%s from %s\n", program_invocation_short_name,
- PACKAGE_STRING);
+ FILE *output = stdout;
+ fputs(USAGE_HEADER, output);
+ fprintf(output, _(" %s [options] <newrootdir> <init> <args to init>\n"),
+ program_invocation_short_name);
+
+ fputs(USAGE_SEPARATOR, output);
+ fputs(_("Switch to another filesystem as the root of the mount tree.\n"), output);
+
+ fputs(USAGE_OPTIONS, output);
+ fprintf(output, USAGE_HELP_OPTIONS(16));
+ fprintf(output, USAGE_MAN_TAIL("switch_root(8)"));
+
exit(EXIT_SUCCESS);
}
int main(int argc, char *argv[])
{
char *newroot, *init, **initargs;
-
- if (argv[1] && (!strcmp(argv[1], "--help") || !strcmp(argv[1], "-h")))
- usage(stdout);
- if (argv[1] && (!strcmp(argv[1], "--version") || !strcmp(argv[1], "-V")))
- version();
- if (argc < 3)
- usage(stderr);
+ int c;
+ static const struct option longopts[] = {
+ {"version", no_argument, NULL, 'V'},
+ {"help", no_argument, NULL, 'h'},
+ {NULL, 0, NULL, 0}
+ };
+
+ close_stdout_atexit();
+
+ while ((c = getopt_long(argc, argv, "+Vh", longopts, NULL)) != -1)
+ switch (c) {
+ case 'V':
+ print_version(EXIT_SUCCESS);
+ case 'h':
+ usage();
+ default:
+ errtryhelp(EXIT_FAILURE);
+ }
+ if (argc < 3) {
+ warnx(_("not enough arguments"));
+ errtryhelp(EXIT_FAILURE);
+ }
newroot = argv[1];
init = argv[2];
initargs = &argv[2];
- if (!*newroot || !*init)
- usage(stderr);
+ if (!*newroot || !*init) {
+ warnx(_("bad usage"));
+ errtryhelp(EXIT_FAILURE);
+ }
if (switchroot(newroot))
- errx(EXIT_FAILURE, "failed. Sorry.");
+ errx(EXIT_FAILURE, _("failed. Sorry."));
if (access(init, X_OK))
- warn("cannot access %s", init);
+ warn(_("cannot access %s"), init);
execv(init, initargs);
- err(EXIT_FAILURE, "failed to execute %s", init);
+ errexec(init);
}
-
projects / thirdparty / util-linux.git / blobdiff