cache.py 文件源码

def save_extras(self):
        if not self.cachefile:
            return

        glf = bb.utils.lockfile(self.cachefile + ".lock", shared=True)

        i = os.getpid()
        lf = None
        while not lf:
            lf = bb.utils.lockfile(self.cachefile + ".lock." + str(i), retry=False)
            if not lf or os.path.exists(self.cachefile + "-" + str(i)):
                if lf:
                    bb.utils.unlockfile(lf)
                    lf = None
                i = i + 1
                continue

            with open(self.cachefile + "-" + str(i), "wb") as f:
                p = pickle.Pickler(f, -1)
                p.dump([self.cachedata_extras, self.__class__.CACHE_VERSION])

        bb.utils.unlockfile(lf)
        bb.utils.unlockfile(glf)