binman: Move compression into binman

The compression functions are not actually used by patman, so we don't
need then in the tools module. Also we want to change them to use
bintools, which patman will not support.

Move these into a new comp_util module, within binman.

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

tools/binman/comp_util.py

@@ -0,0 +1,88 @@
+# SPDX-License-Identifier: GPL-2.0+
+# Copyright 2022 Google LLC
+#
+"""Utilities to compress and decompress data"""
+
+import struct
+import tempfile
+
+from patman import tools
+
+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
+    provided by xz.
+
+    This requires 'lz4' and 'lzma_alone' tools. It also requires an output
+    directory to be previously set up, by calling PrepareOutputDir().
+
+    Care is taken to use unique temporary files so that this function can be
+    called from multiple threads.
+
+    Args:
+        indata: Input data to compress
+        algo: Algorithm to use ('none', 'gzip', 'lz4' or 'lzma')
+
+    Returns:
+        Compressed data
+    """
+    if algo == 'none':
+        return indata
+    fname = tempfile.NamedTemporaryFile(prefix='%s.comp.tmp' % algo,
+                                        dir=tools.GetOutputDir()).name
+    tools.WriteFile(fname, indata)
+    if algo == 'lz4':
+        data = tools.Run('lz4', '--no-frame-crc', '-B4', '-5', '-c', fname,
+                         binary=True)
+    # cbfstool uses a very old version of lzma
+    elif algo == 'lzma':
+        outfname = tempfile.NamedTemporaryFile(prefix='%s.comp.otmp' % algo,
+                                               dir=tools.GetOutputDir()).name
+        tools.Run('lzma_alone', 'e', fname, outfname, '-lc1', '-lp0', '-pb0',
+                  '-d8')
+        data = tools.ReadFile(outfname)
+    elif algo == 'gzip':
+        data = tools.Run('gzip', '-c', fname, binary=True)
+    else:
+        raise ValueError("Unknown algorithm '%s'" % algo)
+    if with_header:
+        hdr = struct.pack('<I', len(data))
+        data = hdr + data
+    return data
+
+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
+    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
+    if with_header:
+        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:
+        fd.write(indata)
+    if algo == 'lz4':
+        data = tools.Run('lz4', '-dc', fname, binary=True)
+    elif algo == 'lzma':
+        outfname = tools.GetOutputFilename('%s.decomp.otmp' % algo)
+        tools.Run('lzma_alone', 'd', fname, outfname)
+        data = tools.ReadFile(outfname, binary=True)
+    elif algo == 'gzip':
+        data = tools.Run('gzip', '-cd', fname, binary=True)
+    else:
+        raise ValueError("Unknown algorithm '%s'" % algo)
+    return data