kcov

Kcov is a FreeBSD/Linux/Mac OS code coverage tester for compiled languages, Python and Bash. Kcov was originally a fork of Bcov, but has since evolved to support a large feature set in addition to that of Bcov.

Kcov, like Bcov, uses DWARF debugging information for compiled programs to make it possible to collect coverage information without special compiler switches.

For a video introduction, look at this presentation from SwedenCPP

Installing

Refer to the INSTALL file for build instructions, or use our official Docker image (kcov/kcov):

• kcov/kcov for releases since v31.

Docker images and usage is explained more in the docker page.

How to use it

Basic usage is straight-forward:

kcov /path/to/outdir executable [args for the executable]

/path/to/outdir will contain lcov-style HTML output generated continuously while the application runs. Kcov will also write cobertura- compatible XML output and generic JSON coverage information and can easily be integrated in various CI systems.

Filtering output

It's often useful to filter output, since e.g., /usr/include is seldom of interest. This can be done in two ways:

kcov --exclude-pattern=/usr/include --include-pattern=part/of/path,other/path \
      /path/to/outdir executable

which will do a string-comparison and include everything which contains part/of/path or other/path but exclude everything that has the /usr/include string in it.

kcov --include-path=/my/src/path /path/to/outdir executable
kcov --exclude-path=/usr/include /path/to/outdir executable

Does the same thing, but with proper path lookups.

Merging multiple kcov runs

Kcov can also merge the results of multiple earlier runs. To use this mode, call kcov with --merge, an output path and one or more paths to an earlier run, e.g.,

kcov --merge /tmp/merged-output /tmp/kcov-output1 /tmp/kcov-output2
kcov --merge /tmp/merged-output /tmp/kcov-output*    # With a wildcard

Integration with other systems

kcov is easy to integrate with travis-ci/GitHub actions together with coveralls.io or codecov.io. It can also be used from Jenkins, SonarQube and GitLab CI. Refer to

• vscode for details about vscode + coverage gutters
• coveralls for details about travis-ci + coveralls, or
• codecov for details about travis-ci + codecov
• jenkins for details about how to integrate in Jenkins
• sonarqube for how to use kcov and sonarqube together
• GitHub for use with GitHub
• gitlab for use with GitLab

More information

kcov is written by Simon Kagstrom simon.kagstrom@gmail.com and more information can be found at the web page