Squid internals

The Storage Manager (src/store*.c)
Swapping an object in - storeSwapInStart() / storeClientFileRead()
storeSwapInStart() and storeClientFileRead() are called by storeClientCopy() if the client is a STORE_DISK_CLIENT
storeSwapInStart() opens the file from the relevant storedir
storeClientFileRead() does the following
reads the metadata in to verify the object is the right one
reads the data in to memory
this data is NOT cached!
calls httpReplyParse() to parse the reply header
hands the data to the callback supplied to storeClientCopy()
Each STORE_DISK_CLIENT can have a seperate instance of the same file being swapped in