#pragma once #include "types.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. */ int 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); }; // FIXME: not thread-safe! bool pathIsLockedByMe(const Path & path); }