[PATCH v2 1/5] wic: Ensure internal workdir is not reused

["Paul Barker" <pbarker@konsulko.com>]

If a path is specified for the internal wic working directory using
the -w/--workdir argument then it must not already exist. Re-using a
previous workdir could easily result in rootfs and intermediate files
from a previous build being added to the current image.

Signed-off-by: Paul Barker <pbarker@konsulko.com>
---
 scripts/lib/wic/plugins/imager/direct.py | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/scripts/lib/wic/plugins/imager/direct.py b/scripts/lib/wic/plugins/imager/direct.py
index b329568c7a..f107e60089 100644
--- a/scripts/lib/wic/plugins/imager/direct.py
+++ b/scripts/lib/wic/plugins/imager/direct.py
@@ -62,7 +62,7 @@ class DirectPlugin(ImagerPlugin):
 
         self.name = "%s-%s" % (os.path.splitext(os.path.basename(wks_file))[0],
                                strftime("%Y%m%d%H%M"))
-        self.workdir = options.workdir or tempfile.mkdtemp(dir=self.outdir, prefix='tmp.wic.')
+        self.workdir = self.setup_workdir(options.workdir)
         self._image = None
         self.ptable_format = self.ks.bootloader.ptable
         self.parts = self.ks.partitions
@@ -78,6 +78,16 @@ class DirectPlugin(ImagerPlugin):
         self._image = PartitionedImage(image_path, self.ptable_format,
                                        self.parts, self.native_sysroot)
 
+    def setup_workdir(self, workdir):
+        if workdir:
+            if os.path.exists(workdir):
+                raise WicError("Internal workdir '%s' specified in wic arguments already exists!" % (workdir))
+
+            os.makedirs(workdir)
+            return workdir
+        else:
+            return tempfile.mkdtemp(dir=self.outdir, prefix='tmp.wic.')
+
     def do_create(self):
         """
         Plugin entry point.
-- 
2.26.2