TError TMount::Find(TPath path, const TPath mounts) {
path = path.NormalPath();
auto device = path.GetDev();
if (!device)
return TError(EError::Unknown, "device not found: " + path.ToString() + ")");
FILE* f = setmntent(mounts.c_str(), "r");
if (!f)
return TError(EError::Unknown, errno, "setmntent(" + mounts.ToString() + ")");
struct mntent* m, mntbuf;
TScopedMem buf(4096);
TError error(EError::Unknown, "mountpoint not found: " + path.ToString() + ")");
while ((m = getmntent_r(f, &mntbuf, (char *)buf.GetData(), buf.GetSize()))) {
TPath source(m->mnt_fsname);
TPath target(m->mnt_dir);
if (target.InnerPath(path).IsEmpty() ||
source.GetBlockDev() != device)
continue;
Source = source;
Target = target;
Type = m->mnt_type;
Data.clear();
error = SplitString(m->mnt_opts, ',', Data);
break;
}
endmntent(f);
return error;
}
TError TMount::Move(TPath destination) {
int ret = mount(Target.ToString().c_str(), destination.ToString().c_str(), NULL, MS_MOVE, NULL);
if (ret)
return TError(EError::Unknown, errno, "mount(" + Target.ToString() + ", " + destination.ToString() + ", MS_MOVE)");
Target = destination;
return TError::Success();
}
TError TNamespaceFd::Open(TPath path) {
Close();
Fd = open(path.c_str(), O_RDONLY | O_NOCTTY | O_NONBLOCK | O_CLOEXEC);
if (Fd < 0)
return TError(EError::Unknown, errno, "Cannot open " + path.ToString());
return TError::Success();
}
TError TTask::ChildMountDev() {
struct {
const std::string path;
unsigned int mode;
unsigned int dev;
} node[] = {
{ "/dev/null", 0666 | S_IFCHR, MKDEV(1, 3) },
{ "/dev/zero", 0666 | S_IFCHR, MKDEV(1, 5) },
{ "/dev/full", 0666 | S_IFCHR, MKDEV(1, 7) },
{ "/dev/random", 0666 | S_IFCHR, MKDEV(1, 8) },
{ "/dev/urandom", 0666 | S_IFCHR, MKDEV(1, 9) },
};
TMount dev("tmpfs", Env->Root + "/dev", "tmpfs", { "mode=755", "size=32m" });
TError error = dev.MountDir(MS_NOSUID | MS_STRICTATIME);
if (error)
return error;
TMount devpts("devpts", Env->Root + "/dev/pts", "devpts",
{ "newinstance", "ptmxmode=0666", "mode=620" ,"gid=5" });
error = devpts.MountDir(MS_NOSUID | MS_NOEXEC);
if (error)
return error;
for (size_t i = 0; i < sizeof(node) / sizeof(node[0]); i++) {
error = ChildCreateNode(Env->Root + node[i].path,
node[i].mode, node[i].dev);
if (error)
return error;
}
TPath ptmx = Env->Root + "/dev/ptmx";
if (symlink("pts/ptmx", ptmx.ToString().c_str()) < 0)
return TError(EError::Unknown, errno, "symlink(/dev/pts/ptmx)");
TPath fd = Env->Root + "/dev/fd";
if (symlink("/proc/self/fd", fd.ToString().c_str()) < 0)
return TError(EError::Unknown, errno, "symlink(/dev/fd)");
TFile f(Env->Root + "/dev/console", 0755);
(void)f.Touch();
return TError::Success();
}
std::string ReadLink(const std::string &path) {
TPath lnk;
TPath f(path);
TError error = f.ReadLink(lnk);
if (error)
throw error.GetMsg();
return lnk.ToString();
}
TError TTask::ChildOpenStdFile(const TPath &path, int expected) {
int ret = open(path.ToString().c_str(), O_CREAT | O_WRONLY | O_APPEND, 0660);
if (ret < 0)
return TError(EError::InvalidValue, errno,
"open(" + path.ToString() + ") -> " +
std::to_string(expected));
if (ret != expected)
return TError(EError::Unknown, EINVAL,
"open(" + path.ToString() + ") -> " +
std::to_string(expected) + ": unexpected fd " +
std::to_string(ret));
ret = fchown(ret, Env->Cred.Uid, Env->Cred.Gid);
if (ret < 0)
return TError(EError::Unknown, errno,
"fchown(" + path.ToString() + ") -> " +
std::to_string(expected));
return TError::Success();
}
void BootstrapCommand(const std::string &cmd, const TPath &path, bool remove) {
if (remove)
(void)path.RemoveAll();
vector<string> lines;
ExpectSuccess(Popen("ldd " + cmd, lines));
for (auto &line : lines) {
vector<string> tokens;
TError error = SplitString(line, ' ', tokens);
if (error)
throw error.GetMsg();
TPath from;
string name;
if (tokens.size() == 2) {
from = StringTrim(tokens[0]);
TPath p(tokens[0]);
name = p.BaseName();
} else if (tokens.size() == 4) {
if (tokens[2] == "")
continue;
from = StringTrim(tokens[2]);
name = StringTrim(tokens[0]);
} else {
continue;
}
TPath dest = path / from.DirName();
if (!dest.Exists()) {
error = dest.MkdirAll(0755);
if (error)
throw error.GetMsg();
}
Expect(system(("cp " + from.ToString() + " " + dest.ToString() + "/" + name).c_str()) == 0);
}
Expect(system(("cp " + cmd + " " + path.ToString()).c_str()) == 0);
}
TError TTask::CreateTmpDir(const TPath &path, std::shared_ptr<TFolder> &dir) const {
bool cleanup = path.ToString().find(config().container().tmp_dir()) == 0;
dir = std::make_shared<TFolder>(path, cleanup);
if (!dir->Exists()) {
TError error = dir->Create(0755, true);
if (error)
return error;
error = path.Chown(Env->Cred.Uid, Env->Cred.Gid);
if (error)
return error;
}
return TError::Success();
}
TError TMount::Snapshot(std::vector<std::shared_ptr<TMount>> &result, const TPath mounts) {
FILE* f = setmntent(mounts.c_str(), "r");
if (!f)
return TError(EError::Unknown, errno, "setmntent(" + mounts.ToString() + ")");
struct mntent* m, mntbuf;
TScopedMem buf(4096);
while ((m = getmntent_r(f, &mntbuf, (char *)buf.GetData(), buf.GetSize()))) {
vector<string> flags;
TError error = SplitString(m->mnt_opts, ',', flags);
if (error) {
endmntent(f);
return error;
}
result.push_back(std::make_shared<TMount>(m->mnt_fsname, m->mnt_dir, m->mnt_type, flags));
}
endmntent(f);
return TError::Success();
}
TError TTask::ChildCreateNode(const TPath &path, unsigned int mode, unsigned int dev) {
if (mknod(path.ToString().c_str(), mode, dev) < 0)
return TError(EError::Unknown, errno, "mknod(" + path.ToString() + ")");
return TError::Success();
}
TError SetupLoopDevice(TPath image, int &dev)
{
static std::mutex BigLoopLock;
int control_fd, image_fd, loop_nr, loop_fd;
struct loop_info64 info;
std::string loop;
int retry = 10;
TError error;
image_fd = open(image.c_str(), O_RDWR | O_CLOEXEC);
if (image_fd < 0) {
error = TError(EError::Unknown, errno, "open(" + image.ToString() + ")");
goto err_image;
}
control_fd = open("/dev/loop-control", O_RDWR | O_CLOEXEC);
if (control_fd < 0) {
error = TError(EError::Unknown, errno, "open(/dev/loop-control)");
goto err_control;
}
BigLoopLock.lock();
again:
loop_nr = ioctl(control_fd, LOOP_CTL_GET_FREE);
if (loop_nr < 0) {
error = TError(EError::Unknown, errno, "ioctl(LOOP_CTL_GET_FREE)");
goto err_get_free;
}
loop = "/dev/loop" + std::to_string(loop_nr);
loop_fd = open(loop.c_str(), O_RDWR | O_CLOEXEC);
if (loop_fd < 0) {
error = TError(EError::Unknown, errno, "open(" + loop + ")");
goto err_loop_open;
}
if (ioctl(loop_fd, LOOP_SET_FD, image_fd) < 0) {
error = TError(EError::Unknown, errno, "ioctl(LOOP_SET_FD)");
if (errno == EBUSY) {
if (!ioctl(loop_fd, LOOP_GET_STATUS64, &info) || errno == ENXIO) {
if (--retry > 0) {
close(loop_fd);
goto again;
}
}
}
goto err_set_fd;
}
memset(&info, 0, sizeof(info));
strncpy((char *)info.lo_file_name, image.c_str(), LO_NAME_SIZE);
if (ioctl(loop_fd, LOOP_SET_STATUS64, &info) < 0) {
error = TError(EError::Unknown, errno, "ioctl(LOOP_SET_STATUS64)");
ioctl(loop_fd, LOOP_CLR_FD, 0);
goto err_set_status;
}
dev = loop_nr;
error = TError::Success();
err_set_status:
err_set_fd:
close(loop_fd);
err_loop_open:
err_get_free:
BigLoopLock.unlock();
close(control_fd);
err_control:
close(image_fd);
err_image:
return error;
}
TError TMount::Remount(TPath path, unsigned long flags) {
if (mount(NULL, path.c_str(), NULL, flags, NULL))
return TError(EError::Unknown, errno, "mount(NULL, " + path.ToString() + ", NULL, " + std::to_string(flags) + ", NULL)");
return TError::Success();
}
friend bool operator>(const TPath& a, const TPath& b) {
return a.ToString() > b.ToString();
}
friend bool operator!=(const TPath& a, const TPath& b) {
return a.ToString() != b.ToString();
}
TPath operator+(const TPath &p) const {
return TPath(Path + p.ToString());
}