[PATCH 25/25] binman: Avoid calculated section data repeatedly

[Simon Glass]

Refactor the implementation slightly so that section data is not
rebuilt when it is already available.

We still have GetData() set up to rebuild the section, since we don't
currently track when things change that might affect a section. For
example, if a blob is updated within a section, we must rebuild it.
Tracking that would be possible but is more complex, so it left for
another time.

Signed-off-by: Simon Glass <sjg at chromium.org>
---

 tools/binman/etype/section.py | 24 +++++++++++++-----------
 1 file changed, 13 insertions(+), 11 deletions(-)

diff --git a/tools/binman/etype/section.py b/tools/binman/etype/section.py
index 570dbfcfd41..3dd5f58c4c2 100644
--- a/tools/binman/etype/section.py
+++ b/tools/binman/etype/section.py
@@ -147,7 +147,7 @@ class Entry_section(Entry):
     def ObtainContents(self):
         return self.GetEntryContents()
 
-    def GetPaddedDataForEntry(self, entry):
+    def GetPaddedDataForEntry(self, entry, entry_data):
         """Get the data for an entry including any padding
 
         Gets the entry data and uses the section pad-byte value to add padding
@@ -170,7 +170,7 @@ class Entry_section(Entry):
             data += tools.GetBytes(self._pad_byte, entry.pad_before)
 
         # Add in the actual entry data
-        data += entry.GetData()
+        data += entry_data
 
         # Handle padding after the entry
         if entry.pad_after:
@@ -197,7 +197,7 @@ class Entry_section(Entry):
         section_data = b''
 
         for entry in self._entries.values():
-            data = self.GetPaddedDataForEntry(entry)
+            data = self.GetPaddedDataForEntry(entry, entry.GetData())
             # Handle empty space before the entry
             pad = (entry.offset or 0) - self._skip_at_start - len(section_data)
             if pad > 0:
@@ -210,7 +210,7 @@ class Entry_section(Entry):
                     (len(self._entries), len(section_data)))
         return self.CompressData(section_data)
 
-    def GetPaddedData(self):
+    def GetPaddedData(self, data=None):
         """Get the data for a section including any padding
 
         Gets the section data and uses the parent section's pad-byte value to
@@ -225,7 +225,9 @@ class Entry_section(Entry):
             after it (bytes)
         """
         section = self.section or self
-        return section.GetPaddedDataForEntry(self)
+        if data is None:
+            data = self.GetData()
+        return section.GetPaddedDataForEntry(self, data)
 
     def GetData(self):
         """Get the contents of an entry
@@ -264,8 +266,10 @@ class Entry_section(Entry):
             self._SortEntries()
         self._ExpandEntries()
 
-        size = self.CheckSize()
-        self.size = size
+        data = self._BuildSectionData()
+        self.SetContents(data)
+
+        self.CheckSize()
 
         offset = super().Pack(offset)
         self.CheckEntries()
@@ -542,14 +546,12 @@ class Entry_section(Entry):
             for name, info in offset_dict.items():
                 self._SetEntryOffsetSize(name, *info)
 
-
     def CheckSize(self):
-        data = self._BuildSectionData()
-        contents_size = len(data)
+        contents_size = len(self.data)
 
         size = self.size
         if not size:
-            data = self.GetPaddedData()
+            data = self.GetPaddedData(self.data)
             size = len(data)
             size = tools.Align(size, self.align_size)
 
-- 
2.29.0.rc1.297.gfa9743e501-goog