Squid internals

The Storage Manager (src/store*.c)
Marking a StoreEntry for release when it is finished being used
storeRelease(StoreEntry *)
Attempt to release the object - if the object is being used, call storeReleaseRequest()
storeReleaseRequest(StoreEntry *)
Clear the cacheable flag, set the release request flag, and set the store key private

Referencing / derefencing a StoreEntry

storeLockObject(StoreEntry *)
storeUnlockObject(StoreEntry *)
If there are no pending clients and the release flag is set, call storeRelease()