forked from lix-project/lix
e349f2c0a3
POSIX file locks are essentially incompatible with multithreading. BSD locks have much saner semantics. We need this now that there can be multiple concurrent LocalStore::buildPaths() invocations.
39 lines
902 B
C++
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);
|
|
};
|
|
|
|
}
|