[PATCH 10/25] binman: Move section-building code into a function

[Alper Nebi Yasak]

On 19/10/2020 05:41, Simon Glass wrote:
> Create a new _BuildSectionData() to hold the code that is now in
> GetData(), so that it is clearly separated from entry.GetData() base
> function.
> 
> Separate out the 'pad-before' processing to make this easier to
> understand.
> 
> Unfortunately this breaks the testDual test. Rather than squash several
> patches into an un-reviewable glob, disable the test for now.
> 
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
> 
>  tools/binman/etype/section.py | 35 +++++++++++++++++++++++++++++------
>  tools/binman/ftest.py         |  3 ++-
>  2 files changed, 31 insertions(+), 7 deletions(-)
> 
> diff --git a/tools/binman/etype/section.py b/tools/binman/etype/section.py
> index 9222042f5d8..d05adf00274 100644
> --- a/tools/binman/etype/section.py
> +++ b/tools/binman/etype/section.py
> @@ -144,24 +144,47 @@ class Entry_section(Entry):
>      def ObtainContents(self):
>          return self.GetEntryContents()
>  
> -    def GetData(self):
> +    def _BuildSectionData(self):
> +        """Build the contents of a section
> +
> +        This places all entries at the right place, dealing with padding before
> +        and after entries. It does not do padding for the section itself (the
> +        pad-before and pad-after properties in the section items) since that is
> +        handled by the parent section.
> +
> +        Returns:
> +            Contents of the section (bytes)
> +        """
>          section_data = b''
>  
>          for entry in self._entries.values():
>              data = entry.GetData()
> -            base = self.pad_before + (entry.offset or 0) - self._skip_at_start
> -            pad = base - len(section_data) + (entry.pad_before or 0)
> +            # Handle empty space before the entry
> +            pad = (entry.offset or 0) - self._skip_at_start - len(section_data)
>              if pad > 0:
>                  section_data += tools.GetBytes(self._pad_byte, pad)
> +
> +            # Handle padding before the entry
> +            if entry.pad_before:
> +                section_data += tools.GetBytes(self._pad_byte, entry.pad_before)

Consider this fragment:

    section {
        skip-at-start = <16>;

        blob {
            pad-before = <16>;
            filename = "foo";
        }
    }

Is this invalid as 'blob' isn't offset > skip-at-start? This wouldn't
be padded in the earlier code, but would be padded after this (assuming
it doesn't error out) -- was that a bug or undefined behaviour or
something?

> +
> +            # Add in the actual entry data
>              section_data += data
> +
> +            # Handle padding after the entry
> +            if entry.pad_after:
> +                section_data += tools.GetBytes(self._pad_byte, entry.pad_after)
> +
>          if self.size:
> -            pad = self.size - len(section_data)
> -            if pad > 0:
> -                section_data += tools.GetBytes(self._pad_byte, pad)
> +            section_data += tools.GetBytes(self._pad_byte,
> +                                           self.size - len(section_data))
>          self.Detail('GetData: %d entries, total size %#x' %
>                      (len(self._entries), len(section_data)))
>          return self.CompressData(section_data)
>  
> +    def GetData(self):
> +        return self._BuildSectionData()
> +
>      def GetOffsets(self):
>          """Handle entries that want to set the offset/size of other entries
>  
> diff --git a/tools/binman/ftest.py b/tools/binman/ftest.py
> index e265941a392..3c6eb7f6736 100644
> --- a/tools/binman/ftest.py
> +++ b/tools/binman/ftest.py
> @@ -706,7 +706,8 @@ class TestFunctional(unittest.TestCase):
>          """Test a simple binman run with debugging enabled"""
>          self._DoTestFile('005_simple.dts', debug=True)
>  
> -    def testDual(self):
> +    # Disable for now until padding of images is supported
> +    def xtestDual(self):

I think you could use @unittest.skip() here, but perhaps it's not worth
doing a v2 for that (especially since you're re-enabling it later in the
series).

>          """Test that we can handle creating two images
>  
>          This also tests image padding.
>