[Buildroot] [PATCH v2 2/3] autobuild-run: initial implementation of do_reproducible_build()

[Atharva Lele <itsatharva@gmail.com>]

This new function will call do_build() twice to produce two builds
and then check their reproducibility

Signed-off-by: Atharva Lele <itsatharva@gmail.com>

---
Changes v1 -> v2:
  - make clean outputs to devnull (suggested by arnout)
  - remove unnecessary arguments to make clean (suggested by arnout)

Signed-off-by: Atharva Lele <itsatharva@gmail.com>
---
 scripts/autobuild-run | 40 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/scripts/autobuild-run b/scripts/autobuild-run
index 5d76583..a4ddb5b 100755
--- a/scripts/autobuild-run
+++ b/scripts/autobuild-run
@@ -494,6 +494,46 @@ def do_build(**kwargs):
     log_write(log, "INFO: build successful")
     return 0
 
+def do_reproducible_build(**kwargs):
+    """Run the builds for reproducibility testing
+
+    Build twice with the same configuration. Calls do_build() to
+    perform the actual build.
+    """
+
+    idir = "instance-%d" % kwargs['instance']
+    outputdir = os.path.join(idir, "output")
+    log = kwargs['log']
+    
+    # Start the first build
+    log_write(log, "INFO: Reproducible Build Test, starting build 1")
+    ret = do_build(**kwargs)
+    if ret != 0:
+        log_write(log, "INFO: build 1 failed, skipping build 2")
+        return ret
+    
+    # First build has been built, move files and start build 2
+    os.rename(os.path.join(outputdir, "images"), os.path.join(outputdir, "images-1"))
+
+    # Clean up build 1
+    if kwargs['debug']:
+        devnull = log
+    else:
+        devnull = open(os.devnull, "w")
+    cmd = ["make", "O=%s" % outputdir, "clean"]
+    subprocess.call(cmd, stdout=devnull, stderr=devnull)
+
+    # Start the second build
+    log_write(log, "INFO: Reproducible Build Test, starting build 2")
+    ret = do_build(**kwargs)
+    if ret != 0:
+        log_write(log, "INFO: build 2 failed")
+        return ret
+
+    # Assuming both have built successfully
+    ret = check_reproducibility(**kwargs)
+    return ret
+
 def send_results(result, **kwargs):
     """Prepare and store/send tarball with results
 
-- 
2.20.1