amangour30 / cs387-toydb

toydb

###Follow the original documentation except:

• Include both raid.h and pf.h in the main program.
• Only use PF_GetThisPage to access pages. This function will return PFE_OK if the page is in memory or PFE_DISK if the page is being fetched from disk, otherwise an error code.
• Use fetchPFRAID_buf(PFRAID_buf_ele* ptr) to check the status of the Page Access. This method can return PFE_INVALIDFETCH if it is an invalid identifier, PFE_FETCHED if the page has been fetched and PFE_PENDING if the page is still being fetched.
• Call stepTime() to update the page fetch status.
• Call cost() to get the current cost.
• Call resetCost() to set the current cost to 0.
• Call PF_TakeSnapshot(char ** files) to take a snpashot of the file names provded in the argument. Only one snapshot can be taken.
• To access snapshot of a file open both the and snapshot_.
• Call PF_ReadSnapshot on the snapshot. The page will be automatically unfixed and you need not call PF_UnfixPage.