1#! /usr/bin/env python
2
3# Copyright (C) 2012 The Android Open Source Project
4#
5# Licensed under the Apache License, Version 2.0 (the "License");
6# you may not use this file except in compliance with the License.
7# You may obtain a copy of the License at
8#
9#      http://www.apache.org/licenses/LICENSE-2.0
10#
11# Unless required by applicable law or agreed to in writing, software
12# distributed under the License is distributed on an "AS IS" BASIS,
13# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14# See the License for the specific language governing permissions and
15# limitations under the License.
16
17from __future__ import print_function
18import getopt, posixpath, signal, struct, sys
19
20def usage(argv0):
21  print("""
22Usage: %s [-v] sparse_image_file ...
23 -v             verbose output
24""" % ( argv0 ))
25  sys.exit(2)
26
27def main():
28
29  signal.signal(signal.SIGPIPE, signal.SIG_DFL)
30
31  me = posixpath.basename(sys.argv[0])
32
33  # Parse the command line
34  verbose = 0			# -v
35  try:
36    opts, args = getopt.getopt(sys.argv[1:],
37                               "v",
38                               ["verbose"])
39  except getopt.GetoptError, e:
40    print(e)
41    usage(me)
42  for o, a in opts:
43    if o in ("-v", "--verbose"):
44      verbose += 1
45    else:
46      print("Unrecognized option \"%s\"" % (o))
47      usage(me)
48
49  if len(args) == 0:
50    print("No sparse_image_file specified")
51    usage(me)
52
53  for path in args:
54    FH = open(path, 'rb')
55    header_bin = FH.read(28)
56    header = struct.unpack("<I4H4I", header_bin)
57
58    magic = header[0]
59    major_version = header[1]
60    minor_version = header[2]
61    file_hdr_sz = header[3]
62    chunk_hdr_sz = header[4]
63    blk_sz = header[5]
64    total_blks = header[6]
65    total_chunks = header[7]
66    image_checksum = header[8]
67
68    if magic != 0xED26FF3A:
69      print("%s: %s: Magic should be 0xED26FF3A but is 0x%08X"
70            % (me, path, magic))
71      continue
72    if major_version != 1 or minor_version != 0:
73      print("%s: %s: I only know about version 1.0, but this is version %u.%u"
74            % (me, path, major_version, minor_version))
75      continue
76    if file_hdr_sz != 28:
77      print("%s: %s: The file header size was expected to be 28, but is %u."
78            % (me, path, file_hdr_sz))
79      continue
80    if chunk_hdr_sz != 12:
81      print("%s: %s: The chunk header size was expected to be 12, but is %u."
82            % (me, path, chunk_hdr_sz))
83      continue
84
85    print("%s: Total of %u %u-byte output blocks in %u input chunks."
86          % (path, total_blks, blk_sz, total_chunks))
87
88    if image_checksum != 0:
89      print("checksum=0x%08X" % (image_checksum))
90
91    if not verbose:
92      continue
93    print("            input_bytes      output_blocks")
94    print("chunk    offset     number  offset  number")
95    offset = 0
96    for i in xrange(1,total_chunks+1):
97      header_bin = FH.read(12)
98      header = struct.unpack("<2H2I", header_bin)
99      chunk_type = header[0]
100      reserved1 = header[1]
101      chunk_sz = header[2]
102      total_sz = header[3]
103      data_sz = total_sz - 12
104
105      print("%4u %10u %10u %7u %7u" % (i, FH.tell(), data_sz, offset, chunk_sz),
106            end=" ")
107
108      if chunk_type == 0xCAC1:
109        if data_sz != (chunk_sz * blk_sz):
110          print("Raw chunk input size (%u) does not match output size (%u)"
111                % (data_sz, chunk_sz * blk_sz))
112          break;
113        else:
114          print("Raw data", end="")
115          FH.read(data_sz)
116      elif chunk_type == 0xCAC2:
117        if data_sz != 4:
118          print("Fill chunk should have 4 bytes of fill, but this has %u"
119                % (data_sz), end="")
120          break;
121        else:
122          fill_bin = FH.read(4)
123          fill = struct.unpack("<I", fill_bin)
124          print("Fill with 0x%08X" % (fill))
125      elif chunk_type == 0xCAC3:
126        if data_sz != 0:
127          print("Don't care chunk input size is non-zero (%u)" % (data_sz))
128          break;
129        else:
130          print("Don't care", end="")
131      elif chunk_type == 0xCAC4:
132        if data_sz != 4:
133          print("CRC32 chunk should have 4 bytes of CRC, but this has %u"
134                % (data_sz), end="")
135          break;
136        else:
137          crc_bin = FH.read(4)
138          crc = struct.unpack("<I", crc)
139          print("Unverified CRC32 0x%08X" % (crc))
140      else:
141          print("Unknown chunk type 0x%04X" % (chunk_type), end="")
142          break;
143
144      if verbose > 1:
145        header = struct.unpack("<12B", header_bin)
146        print(" (%02X%02X %02X%02X %02X%02X%02X%02X %02X%02X%02X%02X)"
147              % (header[0], header[1], header[2], header[3],
148                 header[4], header[5], header[6], header[7],
149                 header[8], header[9], header[10], header[11]))
150      else:
151        print()
152
153      offset += chunk_sz
154
155    print("     %10u            %7u         End" % (FH.tell(), offset))
156
157    if total_blks != offset:
158      print("The header said we should have %u output blocks, but we saw %u"
159            % (total_blks, offset))
160
161    junk_len = len(FH.read())
162    if junk_len:
163      print("There were %u bytes of extra data at the end of the file."
164            % (junk_len))
165
166  sys.exit(0)
167
168if __name__ == "__main__":
169  main()
170