nix-gh/src/libstore/pathlocks.hh

39 lines
902 B
C++

#pragma once
#include "util.hh"
namespace nix {
/* Open (possibly create) a lock file and return the file descriptor.
-1 is returned if create is false and the lock could not be opened
because it doesn't exist. Any other error throws an exception. */
AutoCloseFD openLockFile(const Path & path, bool create);
/* Delete an open lock file. */
void deleteLockFile(const Path & path, int fd);
enum LockType { ltRead, ltWrite, ltNone };
bool lockFile(int fd, LockType lockType, bool wait);
class PathLocks
{
private:
typedef std::pair<int, Path> FDPair;
list<FDPair> fds;
bool deletePaths;
public:
PathLocks();
PathLocks(const PathSet & paths,
const string & waitMsg = "");
bool lockPaths(const PathSet & _paths,
const string & waitMsg = "",
bool wait = true);
~PathLocks();
void unlock();
void setDeletion(bool deletePaths);
};
}