off_t is a signed type and depending on the platform, it can be "long" or "long long", so cast to long long for printf(). ok stsp

change the three hardcoded seeds to fresh ones generated on demand via arc4random. Suggested/fixed by and ok stsp@

ok thomas_adam millert

ok millert stsp

The stretchblk() function needs to compare data located after the block which has just been matched. However, upon entry it was resetting the file pointer of the delta base to the beginning(!) of the block. The other file is correctly positioned after the block. In many cases the data won't match and stretchblk() will not stretch the matched block. But when the data did happen to match this resulted in a bogus delta, and wrong file contents when the delta was applied. Fix this by setting the delta base file pointer to end of the block. Problem reported by naddy after our server refused a pack file which was sent by 'got send'. I could reproduce the issue by running the 'gotadmin pack' command on a copy of naddy's repository. ok naddy

This simplifies pack file creation. A delta base could be read from a loose object, a packfile, or it might be available in a temporary file. All these cases can now be handled the same way. We may need to open, close, and re-open a given delta base multiple times while packing.