Mesos is a tool to gather binary code coverage on all user-land Windows targets without the need for source or recompilation. It also provides an automatic mechanism to save a full minidump of a process if it crashes under mesos.

Mesos is technically just a really fast debugger, capable of handling tens of millions of breakpoints. Using this debugger, we apply breakpoints to every single basic block in a program. These breakpoints are removed as they are hit. Thus, mesos converges to 0-cost coverage as gathering coverage only has a cost the first time the basic block is hit.

Features

Code coverage

Automatic full minidump saving

IDA Coloring

Performance

• We can register (request breakpoints to be at module load) about ~6 million/second
• We can apply them (actually install the breakpoints into the target at about ~3 million/second
• We can clear breakpoints at about 15 million/second
• We can hit and handle about 10k breakpoints/second

Given breakpoints are cleared as they’re hit for coverage, that means you can observe 10k new blocks per second. Once you’ve hit a breakpoint they no longer have a performance cost!

C:\dev\mesos\examples\benchmark>cargo run --release

    Finished release [optimized + debuginfo] target(s) in 0.03s

     Running `target\release\benchmark.exe`

mesos  is 64-bit: true

target is 64-bit: true

Registered    1000000 breakpoints in   0.162230 seconds |  6164072.8 / second

Applied       1000000 breakpoints in   0.321347 seconds |  3111897.0 / second

Cleared       1000000 breakpoints in   0.067024 seconds | 14920028.6 / second

Hit            100000 breakpoints in  10.066440 seconds |     9934.0 / second

Install && Use