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#include "util.hh"
#include "processes.hh"
#include "strings.hh"
#include "current-process.hh"
#include "sync.hh"
#include "finally.hh"
#include "serialise.hh"
#include "cgroup.hh"
#include "signals.hh"
#include "environment-variables.hh"
#include "file-system.hh"
#include <array>
#include <cctype>
#include <cerrno>
#include <climits>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <future>
#include <iostream>
#include <mutex>
#include <sstream>
#include <thread>
#include <fcntl.h>
#include <grp.h>
#include <pwd.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <sys/time.h>
#include <sys/un.h>
#include <unistd.h>
#ifdef __APPLE__
#include <sys/syscall.h>
#include <mach-o/dyld.h>
#endif
#ifdef __linux__
#include <sys/prctl.h>
#include <sys/resource.h>
#include <sys/mman.h>
#include <cmath>
#endif
#ifdef NDEBUG
#error "Lix may not be built with assertions disabled (i.e. with -DNDEBUG)."
#endif
namespace nix {
//////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////
void ignoreException(Verbosity lvl)
{
/* Make sure no exceptions leave this function.
printError() also throws when remote is closed. */
try {
try {
throw;
} catch (std::exception & e) {
printMsg(lvl, "error (ignored): %1%", e.what());
}
} catch (...) { }
}
//////////////////////////////////////////////////////////////////////
#if __linux__
static AutoCloseFD fdSavedMountNamespace;
static AutoCloseFD fdSavedRoot;
#endif
void saveMountNamespace()
{
#if __linux__
static std::once_flag done;
std::call_once(done, []() {
fdSavedMountNamespace = AutoCloseFD{open("/proc/self/ns/mnt", O_RDONLY)};
if (!fdSavedMountNamespace)
throw SysError("saving parent mount namespace");
fdSavedRoot = AutoCloseFD{open("/proc/self/root", O_RDONLY)};
});
#endif
}
void restoreMountNamespace()
{
#if __linux__
try {
auto savedCwd = absPath(".");
if (fdSavedMountNamespace && setns(fdSavedMountNamespace.get(), CLONE_NEWNS) == -1)
throw SysError("restoring parent mount namespace");
if (fdSavedRoot) {
if (fchdir(fdSavedRoot.get()))
throw SysError("chdir into saved root");
if (chroot("."))
throw SysError("chroot into saved root");
}
if (chdir(savedCwd.c_str()) == -1)
throw SysError("restoring cwd");
} catch (Error & e) {
debug(e.msg());
}
#endif
}
void unshareFilesystem()
{
#ifdef __linux__
if (unshare(CLONE_FS) != 0 && errno != EPERM)
throw SysError("unsharing filesystem state in download thread");
#endif
}
}
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