#!/usr/bin/env python
#
# Copyright (c) 2008 Martin Decky
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
#
# - Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# - Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
# - The name of the author may not be used to endorse or promote products
# derived from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#
"""
HORD encapsulator
"""
import sys
import os
import xstruct
HEADER = """little:
char tag[4] /* 'HORD' */
uint8_t version /* version */
uint8_t encoding /* encoding */
uint32_t header_size /* header size */
uint64_t payload_size /* payload size */
"""
HORD_LSB = 1
def align_up(size, alignment):
"Align upwards to a given alignment"
return (((size) + ((alignment) - 1)) & ~((alignment) - 1))
def usage(prname):
"Print usage syntax"
print prname + " <ALIGNMENT> <FS_IMAGE> <HORD_IMAGE>"
def main():
if (len(sys.argv) < 4):
usage(sys.argv[0])
return
if (not sys.argv[1].isdigit()):
print "<ALIGNMENT> must be a number"
return
align = int(sys.argv[1], 0)
if (align <= 0):
print "<ALIGNMENT> must be positive"
return
fs_image = os.path.abspath(sys.argv[2])
if (not os.path.isfile(fs_image)):
print "<FS_IMAGE> must be a file"
return
inf = file(fs_image, "rb")
outf = file(sys.argv[3], "wb")
header = xstruct.create(HEADER)
header_size = header.size()
payload_size = os.path.getsize(fs_image)
header_size_aligned = align_up(header_size, align)
payload_size_aligned = align_up(payload_size, align)
header.tag = "HORD"
header.version = 1
header.encoding = HORD_LSB
header.header_size = header_size_aligned
header.payload_size = payload_size_aligned
outf.write(header.pack())
outf.write(xstruct.create("little: padding[%d]" % (header_size_aligned - header_size)).pack())
outf.write(inf.read())
padding = payload_size_aligned - payload_size
if (padding > 0):
outf.write(xstruct.create("little: padding[%d]" % padding).pack())
inf.close()
outf.close()
if __name__ == '__main__':
main()