patman: Add functions to compress and decompress data

Add utility functions to compress and decompress using lz4 and lzma
algorithms. In the latter case these use the legacy lzma support favoured
by coreboot's CBFS.

No tests are provided as these functions will be tested by the CBFS
tests in a separate patch.

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

diff --git a/tools/binman/README b/tools/binman/README
index 0ff30ef6fd9f3b7098940a315f42a428274c7322..7eda244bbe2e6d1bc5b1f7b534329c4237fd3b36 100644 (file)
--- a/tools/binman/README
+++ b/tools/binman/README
@@ -183,7 +183,8 @@ Running binman
 
 First install prerequisites, e.g.
 
-       sudo apt-get install python-pyelftools python3-pyelftools
+       sudo apt-get install python-pyelftools python3-pyelftools lzma-alone \
+               liblz4-tool
 
 Type:
 

diff --git a/tools/patman/tools.py b/tools/patman/tools.py
index 0b3049f91f4ba8a588b750be0a7188040f00d542..69d03d38608dc7206d8c36851d80c88914d19fa3 100644 (file)
--- a/tools/patman/tools.py
+++ b/tools/patman/tools.py
@@ -374,3 +374,69 @@ def ToBytes(string):
     if sys.version_info[0] >= 3:
         return string.encode('utf-8')
     return string
+
+def Compress(indata, algo):
+    """Compress some data using a given algorithm
+
+    Note that for lzma this uses an old version of the algorithm, not that
+    provided by xz.
+
+    This requires 'lz4' and 'lzma_alone' tools. It also requires an output
+    directory to be previously set up, by calling PrepareOutputDir().
+
+    Args:
+        indata: Input data to compress
+        algo: Algorithm to use ('none', 'gzip', 'lz4' or 'lzma')
+
+    Returns:
+        Compressed data
+    """
+    if algo == 'none':
+        return indata
+    fname = GetOutputFilename('%s.comp.tmp' % algo)
+    WriteFile(fname, indata)
+    if algo == 'lz4':
+        data = Run('lz4', '--no-frame-crc', '-c', fname, binary=True)
+    # cbfstool uses a very old version of lzma
+    elif algo == 'lzma':
+        outfname = GetOutputFilename('%s.comp.otmp' % algo)
+        Run('lzma_alone', 'e', fname, outfname, '-lc1', '-lp0', '-pb0', '-d8')
+        data = ReadFile(outfname)
+    elif algo == 'gzip':
+        data = Run('gzip', '-c', fname, binary=True)
+    else:
+        raise ValueError("Unknown algorithm '%s'" % algo)
+    return data
+
+def Decompress(indata, algo):
+    """Decompress some data using a given algorithm
+
+    Note that for lzma this uses an old version of the algorithm, not that
+    provided by xz.
+
+    This requires 'lz4' and 'lzma_alone' tools. It also requires an output
+    directory to be previously set up, by calling PrepareOutputDir().
+
+    Args:
+        indata: Input data to decompress
+        algo: Algorithm to use ('none', 'gzip', 'lz4' or 'lzma')
+
+    Returns:
+        Compressed data
+    """
+    if algo == 'none':
+        return indata
+    fname = GetOutputFilename('%s.decomp.tmp' % algo)
+    with open(fname, 'wb') as fd:
+        fd.write(indata)
+    if algo == 'lz4':
+        data = Run('lz4', '-dc', fname, binary=True)
+    elif algo == 'lzma':
+        outfname = GetOutputFilename('%s.decomp.otmp' % algo)
+        Run('lzma_alone', 'd', fname, outfname)
+        data = ReadFile(outfname)
+    elif algo == 'gzip':
+        data = Run('gzip', '-cd', fname, binary=True)
+    else:
+        raise ValueError("Unknown algorithm '%s'" % algo)
+    return data