build: Generate "reproducible" version strings on "clean" builds

If the build environment looks "clean" then don't add the build
hostname or build time to the version string.  This makes the default
build string reproducible across builds.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

1 files changed, 6 insertions, 4 deletions

diff --git a/scripts/buildversion.py b/scripts/buildversion.py
index 56bfcfa..c3a83b0 100755
--- a/scripts/buildversion.py
+++ b/scripts/buildversion.py
@@ -92,14 +92,16 @@ def main():
     cleanbuild, toolstr = tool_versions(options.tools)
 
     ver = git_version()
+    cleanbuild = cleanbuild and ver and 'dirty' not in ver
     if not ver:
         ver = file_version()
         if not ver:
             ver = "?"
-    btime = time.strftime("%Y%m%d_%H%M%S")
-    hostname = socket.gethostname()
-    ver = "%s-%s-%s%s" % (ver, btime, hostname, options.extra)
-    write_version(outfile, ver, toolstr)
+    if not cleanbuild:
+        btime = time.strftime("%Y%m%d_%H%M%S")
+        hostname = socket.gethostname()
+        ver = "%s-%s-%s" % (ver, btime, hostname)
+    write_version(outfile, ver + options.extra, toolstr)
 
 if __name__ == '__main__':
     main()