binman: Tidy up pylint warnings in comp_util

Tweak some naming and comments to resolve these. Use WriteFile() to write
the file.

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

tools/binman/cbfs_util.py

@@ -241,9 +241,9 @@ class CbfsFile(object):
         """Handle decompressing data if necessary"""
         indata = self.data
         if self.compress == COMPRESS_LZ4:
-            data = comp_util.Decompress(indata, 'lz4', with_header=False)
+            data = comp_util.decompress(indata, 'lz4', with_header=False)
         elif self.compress == COMPRESS_LZMA:
-            data = comp_util.Decompress(indata, 'lzma', with_header=False)
+            data = comp_util.decompress(indata, 'lzma', with_header=False)
         else:
             data = indata
         self.memlen = len(data)
@@ -362,9 +362,9 @@ class CbfsFile(object):
         elif self.ftype == TYPE_RAW:
             orig_data = data
             if self.compress == COMPRESS_LZ4:
-                data = comp_util.Compress(orig_data, 'lz4', with_header=False)
+                data = comp_util.compress(orig_data, 'lz4', with_header=False)
             elif self.compress == COMPRESS_LZMA:
-                data = comp_util.Compress(orig_data, 'lzma', with_header=False)
+                data = comp_util.compress(orig_data, 'lzma', with_header=False)
             self.memlen = len(orig_data)
             self.data_len = len(data)
             attr = struct.pack(ATTR_COMPRESSION_FORMAT,

tools/binman/comp_util.py

@@ -8,7 +8,7 @@ import tempfile
 
 from patman import tools
 
-def Compress(indata, algo, with_header=True):
+def compress(indata, algo, with_header=True):
     """Compress some data using a given algorithm
 
     Note that for lzma this uses an old version of the algorithm, not that
@@ -21,11 +21,11 @@ def Compress(indata, algo, with_header=True):
     called from multiple threads.
 
     Args:
-        indata: Input data to compress
+        indata (bytes): Input data to compress
-        algo: Algorithm to use ('none', 'gzip', 'lz4' or 'lzma')
+        algo (str): Algorithm to use ('none', 'gzip', 'lz4' or 'lzma')
 
     Returns:
-        Compressed data
+        bytes: Compressed data
     """
     if algo == 'none':
         return indata
@@ -51,7 +51,7 @@ def Compress(indata, algo, with_header=True):
         data = hdr + data
     return data
 
-def Decompress(indata, algo, with_header=True):
+def decompress(indata, algo, with_header=True):
     """Decompress some data using a given algorithm
 
     Note that for lzma this uses an old version of the algorithm, not that
@@ -61,11 +61,11 @@ def Decompress(indata, algo, with_header=True):
     directory to be previously set up, by calling PrepareOutputDir().
 
     Args:
-        indata: Input data to decompress
+        indata (bytes): Input data to decompress
-        algo: Algorithm to use ('none', 'gzip', 'lz4' or 'lzma')
+        algo (str): Algorithm to use ('none', 'gzip', 'lz4' or 'lzma')
 
     Returns:
-        Compressed data
+        (bytes) Compressed data
     """
     if algo == 'none':
         return indata
@@ -73,8 +73,7 @@ def Decompress(indata, algo, with_header=True):
         data_len = struct.unpack('<I', indata[:4])[0]
         indata = indata[4:4 + data_len]
     fname = tools.GetOutputFilename('%s.decomp.tmp' % algo)
-    with open(fname, 'wb') as fd:
+    tools.WriteFile(fname, indata)
-        fd.write(indata)
     if algo == 'lz4':
         data = tools.Run('lz4', '-dc', fname, binary=True)
     elif algo == 'lzma':

tools/binman/entry.py

@@ -1035,7 +1035,7 @@ features to produce new behaviours.
         self.uncomp_data = indata
         if self.compress != 'none':
             self.uncomp_size = len(indata)
-        data = comp_util.Compress(indata, self.compress)
+        data = comp_util.compress(indata, self.compress)
         return data
 
     @classmethod

tools/binman/etype/section.py

@@ -776,7 +776,7 @@ class Entry_section(Entry):
         data = parent_data[offset:offset + child.size]
         if decomp:
             indata = data
-            data = comp_util.Decompress(indata, child.compress)
+            data = comp_util.decompress(indata, child.compress)
             if child.uncomp_size:
                 tout.Info("%s: Decompressing data size %#x with algo '%s' to data size %#x" %
                             (child.GetPath(), len(indata), child.compress,

tools/binman/ftest.py

@@ -1927,7 +1927,7 @@ class TestFunctional(unittest.TestCase):
             self._ResetDtbs()
 
     def _decompress(self, data):
-        return comp_util.Decompress(data, 'lz4')
+        return comp_util.decompress(data, 'lz4')
 
     def testCompress(self):
         """Test compression of blobs"""
@@ -2806,7 +2806,7 @@ class TestFunctional(unittest.TestCase):
     def testExtractCbfsRaw(self):
         """Test extracting CBFS compressed data without decompressing it"""
         data = self._RunExtractCmd('section/cbfs/u-boot-dtb', decomp=False)
-        dtb = comp_util.Decompress(data, 'lzma', with_header=False)
+        dtb = comp_util.decompress(data, 'lzma', with_header=False)
         self.assertEqual(EXTRACT_DTB_SIZE, len(dtb))
 
     def testExtractBadEntry(self):
@@ -4233,13 +4233,13 @@ class TestFunctional(unittest.TestCase):
 
         # Check compressed data
         section1 = self._decompress(rest)
-        expect1 = comp_util.Compress(COMPRESS_DATA + U_BOOT_DATA, 'lz4')
+        expect1 = comp_util.compress(COMPRESS_DATA + U_BOOT_DATA, 'lz4')
         self.assertEquals(expect1, rest[:len(expect1)])
         self.assertEquals(COMPRESS_DATA + U_BOOT_DATA, section1)
         rest1 = rest[len(expect1):]
 
         section2 = self._decompress(rest1)
-        expect2 = comp_util.Compress(COMPRESS_DATA + COMPRESS_DATA, 'lz4')
+        expect2 = comp_util.compress(COMPRESS_DATA + COMPRESS_DATA, 'lz4')
         self.assertEquals(expect2, rest1[:len(expect2)])
         self.assertEquals(COMPRESS_DATA + COMPRESS_DATA, section2)
         rest2 = rest1[len(expect2):]