kuba-- / diff Goto Github PK

I tested the diff implementation with a latest Fedora Workstation x86_64 DVD image in following way:
I had the original image (SHA256: 865c4457dd066d3074c35a8847c8dac1380667c96a4f6d74526324dba14f1b5c) and I incremented one byte by one:

$ cmp -l orig.iso modified2.iso | gawk '{printf "%08X %02X %02X\n", $1, strtonum(0$2), strtonum(0$3)}'
42CC669F 31 32

The resulting modified image file has SHA256: e3cec2d5bf66f262c6b57b639e013cd804b054456305ba570058d67e3e0fe4f4
I then created signatures and delta from original one:

$ ./signature ~/Downloads/orig.iso sigs.dat
$ ./delta sigs.dat ~/Downloads/modified2.iso delta.dat

The resulting signatures file was 125 bytes long and the delta was correspondingly ~192MB

$ ./patch ~/Downloads/orig.iso delta.dat recreated.iso

...it created a broken file. The resulting recreated.iso was only 1.7GB whereas the original one is 1.9GB