def testDecodeElf(self):
"""Test for the MakeElf function"""
if not elf.ELF_TOOLS:
self.skipTest('Python elftools not available')
outdir = tempfile.mkdtemp(prefix='elf.')
expected_text = b'1234'
expected_data = b'wxyz'
elf_fname = os.path.join(outdir, 'elf')
elf.MakeElf(elf_fname, expected_text, expected_data)
data = tools.ReadFile(elf_fname)
load = 0xfef20000
entry = load + 2
expected = expected_text + expected_data
self.assertEqual(elf.ElfInfo(expected, load, entry, len(expected)),
elf.DecodeElf(data, 0))
self.assertEqual(
elf.ElfInfo(b'\0\0' + expected[2:], load, entry, len(expected)),
elf.DecodeElf(data, load + 2))
shutil.rmtree(outdir)
def get_data_and_offset(self, offset=None, pad_byte=None):
"""Obtain the contents of the file, in CBFS format and the offset of
the data within the file
Returns:
tuple:
bytes representing the contents of this file, packed and aligned
for directly inserting into the final CBFS output
offset to the file data from the start of the returned data.
"""
name = _pack_string(self.name)
hdr_len = len(name) + FILE_HEADER_LEN
attr_pos = 0
content = b''
attr = b''
pad = b''
data = self.data
if self.ftype == TYPE_STAGE:
elf_data = elf.DecodeElf(data, self.base_address)
content = struct.pack(STAGE_FORMAT, self.compress,
elf_data.entry, elf_data.load,
len(elf_data.data), elf_data.memsize)
data = elf_data.data
elif self.ftype == TYPE_RAW:
orig_data = data
if self.compress == COMPRESS_LZ4:
data = tools.Compress(orig_data, 'lz4', with_header=False)
elif self.compress == COMPRESS_LZMA:
data = tools.Compress(orig_data, 'lzma', with_header=False)
self.memlen = len(orig_data)
self.data_len = len(data)
attr = struct.pack(ATTR_COMPRESSION_FORMAT,
FILE_ATTR_TAG_COMPRESSION, ATTR_COMPRESSION_LEN,
self.compress, self.memlen)
elif self.ftype == TYPE_EMPTY:
data = tools.GetBytes(self.erase_byte, self.size)
else:
raise ValueError('Unknown type %#x when writing\n' % self.ftype)
if attr:
attr_pos = hdr_len
hdr_len += len(attr)
if self.cbfs_offset is not None:
pad_len = self.cbfs_offset - offset - hdr_len
if pad_len < 0: # pragma: no cover
# Test coverage of this is not available since this should never
# happen. It indicates that get_header_len() provided an
# incorrect value (too small) so that we decided that we could
# put this file at the requested place, but in fact a previous
# file extends far enough into the CBFS that this is not
# possible.
raise ValueError(
"Internal error: CBFS file '%s': Requested offset %#x but current output position is %#x"
% (self.name, self.cbfs_offset, offset))
pad = tools.GetBytes(pad_byte, pad_len)
hdr_len += pad_len
# This is the offset of the start of the file's data,
size = len(content) + len(data)
hdr = struct.pack(FILE_HEADER_FORMAT, FILE_MAGIC, size, self.ftype,
attr_pos, hdr_len)
# Do a sanity check of the get_header_len() function, to ensure that it
# stays in lockstep with this function
expected_len = self.get_header_len()
actual_len = len(hdr + name + attr)
if expected_len != actual_len: # pragma: no cover
# Test coverage of this is not available since this should never
# happen. It probably indicates that get_header_len() is broken.
raise ValueError(
"Internal error: CBFS file '%s': Expected headers of %#x bytes, got %#d"
% (self.name, expected_len, actual_len))
return hdr + name + attr + pad + content + data, hdr_len
