EmbeddedPkg/VirtualRealTimeClockLib: Support SOURCE_DATE_EPOCH

[joeyli]

RISC-V ovmf used VirtualRealTimeClockLib but the default epoch is a compilation time. It causes that the RISC-V ovmf binary image is NOT reproducible.

This patch added the support of SOURCE_DATE_EPOCH by printenv command. If SOURCE_DATE_EPOCH be found then we use it as BUILD_EPOCH. Otherwise we run date command for setting BUILD_EPOCH.

For distributions want a reproducible RISC-V ovmf image, they should export SOURCE_DATE_EPOCH environment variable before building ovmf.

References: https://reproducible-builds.org/docs/source-date-epoch/ Cc: Pete Batard [email protected] Cc: Ard Biesheuvel [email protected]

[github-actions[bot]]

This PR has been automatically marked as stale because it has not had activity in 60 days. It will be closed if no further activity occurs within 7 days. Thank you for your contributions.

[joeyli]

Hi,

Baseo n the CI result, does that mean printenv SOURCE_DATE_EPOCH || date +%s command not be supported by azure-pipelines's shell?

How can I debug it? On azure?

Thanks a lot!

[leiflindholm]

For reference: https://edk2.groups.io/g/devel/message/119756

[joeyli]

Thanks for Leif's suggestion. I will send a new push request.

[leiflindholm]

@joeyli No need to close the PR - you can simply force-push the new version to the branch the PR was created from.

[joeyli]

@joeyli No need to close the PR - you can simply force-push the new version to the branch the PR was created from.

Thanks for your reminder! But I have closed the old PR and submit a new pull request:

https://github.com/tianocore/edk2/pull/5845

Joey Lee