comparison mercurial/lock.py @ 26357:6979a1369185

lock: add a method to prepare the lock for inheritance

This is part of a series that will allow locks to be inherited by subprocesses
in limited circumstances.

26356:927fa07a2ba4

        """
        locker = self._readlock()
        return self._testlock(locker)

    def release(self):
        """release the lock and execute callback function if any

        If the lock has been acquired multiple times, the actual release is
        delayed to the last release call."""

26357:6979a1369185

        """
        locker = self._readlock()
        return self._testlock(locker)

    def prepinherit(self):
        """prepare for the lock to be inherited by a Mercurial subprocess

        Returns a string that will be recognized by the lock in the
        subprocess. Communicating this string to the subprocess needs to be done
        separately -- typically by an environment variable.
        """
        if not self.held:
            raise error.LockInheritanceContractViolation(
                'prepinherit can only be called while lock is held')
        if self._inherited:
            raise error.LockInheritanceContractViolation(
                'prepinherit cannot be called while lock is already inherited')
        if self.releasefn:
            self.releasefn()
        if self._parentheld:
            lockname = self.parentlock
        else:
            lockname = '%s:%s' % (lock._host, self.pid)
        self._inherited = True
        return lockname

    def release(self):
        """release the lock and execute callback function if any

        If the lock has been acquired multiple times, the actual release is
        delayed to the last release call."""