binman: Allow mkimage to use a non-zero fake-blob size

Unfortunately mkimage gets upset with zero-sized files. Update the
ObtainContents() method to support specifying the size, if a fake blob is
created.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Alper Nebi Yasak <alpernebiyasak@gmail.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/tools/binman/ftest.py b/tools/binman/ftest.py
index 18a6b140d54..3d672e6e3e8 100644
--- a/tools/binman/ftest.py
+++ b/tools/binman/ftest.py
@@ -5314,6 +5314,16 @@ fdt         fdtmap                Extract the devicetree blob from the fdtmap
             "Node '/binman/u-boot': Please use 'extend-size' instead of 'expand-size'",
             str(e.exception))
 
+    def testMkimageMissingBlob(self):
+        """Test using mkimage to build an image"""
+        with test_util.capture_sys_output() as (stdout, stderr):
+            self._DoTestFile('229_mkimage_missing.dts', allow_missing=True,
+                             allow_fake_blobs=True)
+        err = stderr.getvalue()
+        self.assertRegex(
+            err,
+            "Image '.*' has faked external blobs and is non-functional: .*")
+
 
 if __name__ == "__main__":
     unittest.main()