Gustavo Noronha Silva a316262603 cmp: print verbose diffs as we find them ...

Before this change, we would first find all changes so we could obtain
the largest offset we will report and use that to set up the padding.

Now we use the file sizes to estimate the largest possible offset.
Not only does this allow us to print earlier, reduces memory usage, as
we do not store diffs to report later, but it also fixes a case in
which our output was different to GNU cmp's - because it also seems
to estimate based on size.

Memory usage drops by a factor of 1000(!), without losing performance
while comparing 2 binaries of hundreds of MBs:

Before:

 Maximum resident set size (kbytes): 2489260

 Benchmark 1: ../target/release/diffutils \
 cmp -l -b /usr/lib64/chromium-browser/chromium-browser /usr/lib64/firefox/libxul.so
   Time (mean ± σ):     14.466 s ±  0.166 s    [User: 12.367 s, System: 2.012 s]
   Range (min … max):   14.350 s … 14.914 s    10 runs

After:

 Maximum resident set size (kbytes): 2636

 Benchmark 1: ../target/release/diffutils \
 cmp -l -b /usr/lib64/chromium-browser/chromium-browser /usr/lib64/firefox/libxul.so
   Time (mean ± σ):     13.724 s ±  0.038 s    [User: 12.263 s, System: 1.372 s]
   Range (min … max):   13.667 s … 13.793 s    10 runs

2024-10-08 08:28:06 -03:00

..

cmp.rs

cmp: print verbose diffs as we find them

2024-10-08 08:28:06 -03:00

context_diff.rs

Fix clippy warnings in tests

2024-09-06 09:27:53 +02:00

diff.rs

Add cmp utility

2024-10-01 13:30:57 -03:00

ed_diff.rs

Fix clippy warnings in tests

2024-09-06 09:27:53 +02:00

lib.rs

Add cmp utility

2024-10-01 13:30:57 -03:00

macros.rs

Fix typos

2024-04-21 16:07:01 +02:00

main.rs

Add cmp utility

2024-10-01 13:30:57 -03:00

normal_diff.rs

Fix clippy warnings in tests

2024-09-06 09:27:53 +02:00

params.rs

Take utility name as first parameter on diffutils

2024-09-26 21:22:24 -03:00

unified_diff.rs

Fix clippy warnings in tests

2024-09-06 09:27:53 +02:00

utils.rs

Add cmp utility

2024-10-01 13:30:57 -03:00